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5e84a031c0b3f4163e9d1f66a99faf4e272736bcd366411d8ab2d957c2e2e1a1 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""Utilities for generating new Python code at runtime."""
import inspect
import itertools
import keyword
import os
import re
import textwrap
from .introspection import find_current_module
__all__ = ['make_function_with_signature']
_ARGNAME_RE = re.compile(r'^[A-Za-z][A-Za-z_]*')
"""
Regular expression used my make_func which limits the allowed argument
names for the created function. Only valid Python variable names in
the ASCII range and not beginning with '_' are allowed, currently.
"""
def make_function_with_signature(func, args=(), kwargs={}, varargs=None,
varkwargs=None, name=None):
"""
Make a new function from an existing function but with the desired
signature.
The desired signature must of course be compatible with the arguments
actually accepted by the input function.
The ``args`` are strings that should be the names of the positional
arguments. ``kwargs`` can map names of keyword arguments to their
default values. It may be either a ``dict`` or a list of ``(keyword,
default)`` tuples.
If ``varargs`` is a string it is added to the positional arguments as
``*<varargs>``. Likewise ``varkwargs`` can be the name for a variable
keyword argument placeholder like ``**<varkwargs>``.
If not specified the name of the new function is taken from the original
function. Otherwise, the ``name`` argument can be used to specify a new
name.
Note, the names may only be valid Python variable names.
"""
pos_args = []
key_args = []
if isinstance(kwargs, dict):
iter_kwargs = kwargs.items()
else:
iter_kwargs = iter(kwargs)
# Check that all the argument names are valid
for item in itertools.chain(args, iter_kwargs):
if isinstance(item, tuple):
argname = item[0]
key_args.append(item)
else:
argname = item
pos_args.append(item)
if keyword.iskeyword(argname) or not _ARGNAME_RE.match(argname):
raise SyntaxError('invalid argument name: {0}'.format(argname))
for item in (varargs, varkwargs):
if item is not None:
if keyword.iskeyword(item) or not _ARGNAME_RE.match(item):
raise SyntaxError('invalid argument name: {0}'.format(item))
def_signature = [', '.join(pos_args)]
if varargs:
def_signature.append(', *{0}'.format(varargs))
call_signature = def_signature[:]
if name is None:
name = func.__name__
global_vars = {'__{0}__func'.format(name): func}
local_vars = {}
# Make local variables to handle setting the default args
for idx, item in enumerate(key_args):
key, value = item
default_var = '_kwargs{0}'.format(idx)
local_vars[default_var] = value
def_signature.append(', {0}={1}'.format(key, default_var))
call_signature.append(', {0}={0}'.format(key))
if varkwargs:
def_signature.append(', **{0}'.format(varkwargs))
call_signature.append(', **{0}'.format(varkwargs))
def_signature = ''.join(def_signature).lstrip(', ')
call_signature = ''.join(call_signature).lstrip(', ')
mod = find_current_module(2)
frm = inspect.currentframe().f_back
if mod:
filename = mod.__file__
modname = mod.__name__
if filename.endswith('.pyc'):
filename = os.path.splitext(filename)[0] + '.py'
else:
filename = '<string>'
modname = '__main__'
# Subtract 2 from the line number since the length of the template itself
# is two lines. Therefore we have to subtract those off in order for the
# pointer in tracebacks from __{name}__func to point to the right spot.
lineno = frm.f_lineno - 2
# The lstrip is in case there were *no* positional arguments (a rare case)
# in any context this will actually be used...
template = textwrap.dedent("""{0}\
def {name}({sig1}):
return __{name}__func({sig2})
""".format('\n' * lineno, name=name, sig1=def_signature,
sig2=call_signature))
code = compile(template, filename, 'single')
eval(code, global_vars, local_vars)
new_func = local_vars[name]
new_func.__module__ = modname
new_func.__doc__ = func.__doc__
return new_func
|
33f59fda24a074bb22b500845802ee0ac897c5065681fe05145ea7f729bb16e6 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Utilities for console input and output.
"""
import codecs
import locale
import re
import math
import multiprocessing
import os
import struct
import sys
import threading
import time
try:
import fcntl
import termios
import signal
_CAN_RESIZE_TERMINAL = True
except ImportError:
_CAN_RESIZE_TERMINAL = False
from .. import conf
from .misc import isiterable
from .decorators import classproperty
__all__ = [
'isatty', 'color_print', 'human_time', 'human_file_size',
'ProgressBar', 'Spinner', 'print_code_line', 'ProgressBarOrSpinner',
'terminal_size']
_DEFAULT_ENCODING = 'utf-8'
class _IPython:
"""Singleton class given access to IPython streams, etc."""
@classproperty
def get_ipython(cls):
try:
from IPython import get_ipython
except ImportError:
pass
return get_ipython
@classproperty
def OutStream(cls):
if not hasattr(cls, '_OutStream'):
cls._OutStream = None
try:
cls.get_ipython()
except NameError:
return None
try:
from ipykernel.iostream import OutStream
except ImportError:
try:
from IPython.zmq.iostream import OutStream
except ImportError:
from IPython import version_info
if version_info[0] >= 4:
return None
try:
from IPython.kernel.zmq.iostream import OutStream
except ImportError:
return None
cls._OutStream = OutStream
return cls._OutStream
@classproperty
def ipyio(cls):
if not hasattr(cls, '_ipyio'):
try:
from IPython.utils import io
except ImportError:
cls._ipyio = None
else:
cls._ipyio = io
return cls._ipyio
@classproperty
def IOStream(cls):
if cls.ipyio is None:
return None
else:
return cls.ipyio.IOStream
@classmethod
def get_stream(cls, stream):
return getattr(cls.ipyio, stream)
def _get_stdout(stderr=False):
"""
This utility function contains the logic to determine what streams to use
by default for standard out/err.
Typically this will just return `sys.stdout`, but it contains additional
logic for use in IPython on Windows to determine the correct stream to use
(usually ``IPython.util.io.stdout`` but only if sys.stdout is a TTY).
"""
if stderr:
stream = 'stderr'
else:
stream = 'stdout'
sys_stream = getattr(sys, stream)
if not isatty(sys_stream) or _IPython.OutStream is None:
return sys_stream
# Our system stream is an atty and we're in ipython.
ipyio_stream = _IPython.get_stream(stream)
if ipyio_stream is not None and isatty(ipyio_stream):
# Use the IPython console output stream
return ipyio_stream
else:
# sys.stdout was set to some other non-TTY stream (a file perhaps)
# so just use it directly
return sys_stream
def isatty(file):
"""
Returns `True` if ``file`` is a tty.
Most built-in Python file-like objects have an `isatty` member,
but some user-defined types may not, so this assumes those are not
ttys.
"""
if (multiprocessing.current_process().name != 'MainProcess' or
threading.current_thread().getName() != 'MainThread'):
return False
if hasattr(file, 'isatty'):
return file.isatty()
# Use two isinstance calls to only evaluate IOStream when necessary.
if (_IPython.OutStream is None or
(not isinstance(file, _IPython.OutStream) and
not isinstance(file, _IPython.IOStream))):
return False
# File is an IPython OutStream or IOStream. Check whether:
# - File name is 'stdout'; or
# - File wraps a Console
if getattr(file, 'name', None) == 'stdout':
return True
if hasattr(file, 'stream'):
# On Windows, in IPython 2 the standard I/O streams will wrap
# pyreadline.Console objects if pyreadline is available; this should
# be considered a TTY.
try:
from pyreadline.console import Console as PyreadlineConsole
except ImportError:
return False
return isinstance(file.stream, PyreadlineConsole)
return False
def terminal_size(file=None):
"""
Returns a tuple (height, width) containing the height and width of
the terminal.
This function will look for the width in height in multiple areas
before falling back on the width and height in astropy's
configuration.
"""
if file is None:
file = _get_stdout()
try:
s = struct.pack(str("HHHH"), 0, 0, 0, 0)
x = fcntl.ioctl(file, termios.TIOCGWINSZ, s)
(lines, width, xpixels, ypixels) = struct.unpack(str("HHHH"), x)
if lines > 12:
lines -= 6
if width > 10:
width -= 1
if lines <= 0 or width <= 0:
raise Exception('unable to get terminal size')
return (lines, width)
except Exception:
try:
# see if POSIX standard variables will work
return (int(os.environ.get('LINES')),
int(os.environ.get('COLUMNS')))
except TypeError:
# fall back on configuration variables, or if not
# set, (25, 80)
lines = conf.max_lines
width = conf.max_width
if lines is None:
lines = 25
if width is None:
width = 80
return lines, width
def _color_text(text, color):
"""
Returns a string wrapped in ANSI color codes for coloring the
text in a terminal::
colored_text = color_text('Here is a message', 'blue')
This won't actually effect the text until it is printed to the
terminal.
Parameters
----------
text : str
The string to return, bounded by the color codes.
color : str
An ANSI terminal color name. Must be one of:
black, red, green, brown, blue, magenta, cyan, lightgrey,
default, darkgrey, lightred, lightgreen, yellow, lightblue,
lightmagenta, lightcyan, white, or '' (the empty string).
"""
color_mapping = {
'black': '0;30',
'red': '0;31',
'green': '0;32',
'brown': '0;33',
'blue': '0;34',
'magenta': '0;35',
'cyan': '0;36',
'lightgrey': '0;37',
'default': '0;39',
'darkgrey': '1;30',
'lightred': '1;31',
'lightgreen': '1;32',
'yellow': '1;33',
'lightblue': '1;34',
'lightmagenta': '1;35',
'lightcyan': '1;36',
'white': '1;37'}
if sys.platform == 'win32' and _IPython.OutStream is None:
# On Windows do not colorize text unless in IPython
return text
color_code = color_mapping.get(color, '0;39')
return '\033[{0}m{1}\033[0m'.format(color_code, text)
def _decode_preferred_encoding(s):
"""Decode the supplied byte string using the preferred encoding
for the locale (`locale.getpreferredencoding`) or, if the default encoding
is invalid, fall back first on utf-8, then on latin-1 if the message cannot
be decoded with utf-8.
"""
enc = locale.getpreferredencoding()
try:
try:
return s.decode(enc)
except LookupError:
enc = _DEFAULT_ENCODING
return s.decode(enc)
except UnicodeDecodeError:
return s.decode('latin-1')
def _write_with_fallback(s, write, fileobj):
"""Write the supplied string with the given write function like
``write(s)``, but use a writer for the locale's preferred encoding in case
of a UnicodeEncodeError. Failing that attempt to write with 'utf-8' or
'latin-1'.
"""
if (_IPython.IOStream is not None and
isinstance(fileobj, _IPython.IOStream)):
# If the output stream is an IPython.utils.io.IOStream object that's
# not going to be very helpful to us since it doesn't raise any
# exceptions when an error occurs writing to its underlying stream.
# There's no advantage to us using IOStream.write directly though;
# instead just write directly to its underlying stream:
write = fileobj.stream.write
try:
write(s)
return write
except UnicodeEncodeError:
# Let's try the next approach...
pass
enc = locale.getpreferredencoding()
try:
Writer = codecs.getwriter(enc)
except LookupError:
Writer = codecs.getwriter(_DEFAULT_ENCODING)
f = Writer(fileobj)
write = f.write
try:
write(s)
return write
except UnicodeEncodeError:
Writer = codecs.getwriter('latin-1')
f = Writer(fileobj)
write = f.write
# If this doesn't work let the exception bubble up; I'm out of ideas
write(s)
return write
def color_print(*args, end='\n', **kwargs):
"""
Prints colors and styles to the terminal uses ANSI escape
sequences.
::
color_print('This is the color ', 'default', 'GREEN', 'green')
Parameters
----------
positional args : str
The positional arguments come in pairs (*msg*, *color*), where
*msg* is the string to display and *color* is the color to
display it in.
*color* is an ANSI terminal color name. Must be one of:
black, red, green, brown, blue, magenta, cyan, lightgrey,
default, darkgrey, lightred, lightgreen, yellow, lightblue,
lightmagenta, lightcyan, white, or '' (the empty string).
file : writeable file-like object, optional
Where to write to. Defaults to `sys.stdout`. If file is not
a tty (as determined by calling its `isatty` member, if one
exists), no coloring will be included.
end : str, optional
The ending of the message. Defaults to ``\\n``. The end will
be printed after resetting any color or font state.
"""
file = kwargs.get('file', _get_stdout())
write = file.write
if isatty(file) and conf.use_color:
for i in range(0, len(args), 2):
msg = args[i]
if i + 1 == len(args):
color = ''
else:
color = args[i + 1]
if color:
msg = _color_text(msg, color)
# Some file objects support writing unicode sensibly on some Python
# versions; if this fails try creating a writer using the locale's
# preferred encoding. If that fails too give up.
write = _write_with_fallback(msg, write, file)
write(end)
else:
for i in range(0, len(args), 2):
msg = args[i]
write(msg)
write(end)
def strip_ansi_codes(s):
"""
Remove ANSI color codes from the string.
"""
return re.sub('\033\\[([0-9]+)(;[0-9]+)*m', '', s)
def human_time(seconds):
"""
Returns a human-friendly time string that is always exactly 6
characters long.
Depending on the number of seconds given, can be one of::
1w 3d
2d 4h
1h 5m
1m 4s
15s
Will be in color if console coloring is turned on.
Parameters
----------
seconds : int
The number of seconds to represent
Returns
-------
time : str
A human-friendly representation of the given number of seconds
that is always exactly 6 characters.
"""
units = [
('y', 60 * 60 * 24 * 7 * 52),
('w', 60 * 60 * 24 * 7),
('d', 60 * 60 * 24),
('h', 60 * 60),
('m', 60),
('s', 1),
]
seconds = int(seconds)
if seconds < 60:
return ' {0:2d}s'.format(seconds)
for i in range(len(units) - 1):
unit1, limit1 = units[i]
unit2, limit2 = units[i + 1]
if seconds >= limit1:
return '{0:2d}{1}{2:2d}{3}'.format(
seconds // limit1, unit1,
(seconds % limit1) // limit2, unit2)
return ' ~inf'
def human_file_size(size):
"""
Returns a human-friendly string representing a file size
that is 2-4 characters long.
For example, depending on the number of bytes given, can be one
of::
256b
64k
1.1G
Parameters
----------
size : int
The size of the file (in bytes)
Returns
-------
size : str
A human-friendly representation of the size of the file
"""
if hasattr(size, 'unit'):
# Import units only if necessary because the import takes a
# significant time [#4649]
from .. import units as u
size = u.Quantity(size, u.byte).value
suffixes = ' kMGTPEZY'
if size == 0:
num_scale = 0
else:
num_scale = int(math.floor(math.log(size) / math.log(1000)))
if num_scale > 7:
suffix = '?'
else:
suffix = suffixes[num_scale]
num_scale = int(math.pow(1000, num_scale))
value = size / num_scale
str_value = str(value)
if suffix == ' ':
str_value = str_value[:str_value.index('.')]
elif str_value[2] == '.':
str_value = str_value[:2]
else:
str_value = str_value[:3]
return "{0:>3s}{1}".format(str_value, suffix)
class _mapfunc(object):
"""
A function wrapper to support ProgressBar.map().
"""
def __init__(self, func):
self._func = func
def __call__(self, i_arg):
i, arg = i_arg
return i, self._func(arg)
class ProgressBar:
"""
A class to display a progress bar in the terminal.
It is designed to be used either with the ``with`` statement::
with ProgressBar(len(items)) as bar:
for item in enumerate(items):
bar.update()
or as a generator::
for item in ProgressBar(items):
item.process()
"""
def __init__(self, total_or_items, ipython_widget=False, file=None):
"""
Parameters
----------
total_or_items : int or sequence
If an int, the number of increments in the process being
tracked. If a sequence, the items to iterate over.
ipython_widget : bool, optional
If `True`, the progress bar will display as an IPython
notebook widget.
file : writable file-like object, optional
The file to write the progress bar to. Defaults to
`sys.stdout`. If ``file`` is not a tty (as determined by
calling its `isatty` member, if any, or special case hacks
to detect the IPython console), the progress bar will be
completely silent.
"""
if file is None:
file = _get_stdout()
if not ipython_widget and not isatty(file):
self.update = self._silent_update
self._silent = True
else:
self._silent = False
if isiterable(total_or_items):
self._items = iter(total_or_items)
self._total = len(total_or_items)
else:
try:
self._total = int(total_or_items)
except TypeError:
raise TypeError("First argument must be int or sequence")
else:
self._items = iter(range(self._total))
self._file = file
self._start_time = time.time()
self._human_total = human_file_size(self._total)
self._ipython_widget = ipython_widget
self._signal_set = False
if not ipython_widget:
self._should_handle_resize = (
_CAN_RESIZE_TERMINAL and self._file.isatty())
self._handle_resize()
if self._should_handle_resize:
signal.signal(signal.SIGWINCH, self._handle_resize)
self._signal_set = True
self.update(0)
def _handle_resize(self, signum=None, frame=None):
terminal_width = terminal_size(self._file)[1]
self._bar_length = terminal_width - 37
def __enter__(self):
return self
def __exit__(self, exc_type, exc_value, traceback):
if not self._silent:
if exc_type is None:
self.update(self._total)
self._file.write('\n')
self._file.flush()
if self._signal_set:
signal.signal(signal.SIGWINCH, signal.SIG_DFL)
def __iter__(self):
return self
def __next__(self):
try:
rv = next(self._items)
except StopIteration:
self.__exit__(None, None, None)
raise
else:
self.update()
return rv
def update(self, value=None):
"""
Update progress bar via the console or notebook accordingly.
"""
# Update self.value
if value is None:
value = self._current_value + 1
self._current_value = value
# Choose the appropriate environment
if self._ipython_widget:
self._update_ipython_widget(value)
else:
self._update_console(value)
def _update_console(self, value=None):
"""
Update the progress bar to the given value (out of the total
given to the constructor).
"""
if self._total == 0:
frac = 1.0
else:
frac = float(value) / float(self._total)
file = self._file
write = file.write
if frac > 1:
bar_fill = int(self._bar_length)
else:
bar_fill = int(float(self._bar_length) * frac)
write('\r|')
color_print('=' * bar_fill, 'blue', file=file, end='')
if bar_fill < self._bar_length:
color_print('>', 'green', file=file, end='')
write('-' * (self._bar_length - bar_fill - 1))
write('|')
if value >= self._total:
t = time.time() - self._start_time
prefix = ' '
elif value <= 0:
t = None
prefix = ''
else:
t = ((time.time() - self._start_time) * (1.0 - frac)) / frac
prefix = ' ETA '
write(' {0:>4s}/{1:>4s}'.format(
human_file_size(value),
self._human_total))
write(' ({:>6.2%})'.format(frac))
write(prefix)
if t is not None:
write(human_time(t))
self._file.flush()
def _update_ipython_widget(self, value=None):
"""
Update the progress bar to the given value (out of a total
given to the constructor).
This method is for use in the IPython notebook 2+.
"""
# Create and display an empty progress bar widget,
# if none exists.
if not hasattr(self, '_widget'):
# Import only if an IPython widget, i.e., widget in iPython NB
from IPython import version_info
if version_info[0] < 4:
from IPython.html import widgets
self._widget = widgets.FloatProgressWidget()
else:
_IPython.get_ipython()
from ipywidgets import widgets
self._widget = widgets.FloatProgress()
from IPython.display import display
display(self._widget)
self._widget.value = 0
# Calculate percent completion, and update progress bar
frac = (value/self._total)
self._widget.value = frac * 100
self._widget.description = ' ({:>6.2%})'.format(frac)
def _silent_update(self, value=None):
pass
@classmethod
def map(cls, function, items, multiprocess=False, file=None, step=100,
ipython_widget=False):
"""
Does a `map` operation while displaying a progress bar with
percentage complete. The map operation may run on arbitrary order
on the items, but the results are returned in sequential order.
::
def work(i):
print(i)
ProgressBar.map(work, range(50))
Parameters
----------
function : function
Function to call for each step
items : sequence
Sequence where each element is a tuple of arguments to pass to
*function*.
multiprocess : bool, optional
If `True`, use the `multiprocessing` module to distribute each
task to a different processor core.
ipython_widget : bool, optional
If `True`, the progress bar will display as an IPython
notebook widget.
file : writeable file-like object, optional
The file to write the progress bar to. Defaults to
`sys.stdout`. If ``file`` is not a tty (as determined by
calling its `isatty` member, if any), the scrollbar will
be completely silent.
step : int, optional
Update the progress bar at least every *step* steps (default: 100).
If ``multiprocess`` is `True`, this will affect the size
of the chunks of ``items`` that are submitted as separate tasks
to the process pool. A large step size may make the job
complete faster if ``items`` is very long.
"""
if multiprocess:
function = _mapfunc(function)
items = list(enumerate(items))
results = cls.map_unordered(function, items, multiprocess=multiprocess,
file=file, step=step,
ipython_widget=ipython_widget)
if multiprocess:
_, results = zip(*sorted(results))
results = list(results)
return results
@classmethod
def map_unordered(cls, function, items, multiprocess=False, file=None,
step=100, ipython_widget=False):
"""
Does a `map` operation while displaying a progress bar with
percentage complete. The map operation may run on arbitrary order
on the items, and the results may be returned in arbitrary order.
::
def work(i):
print(i)
ProgressBar.map(work, range(50))
Parameters
----------
function : function
Function to call for each step
items : sequence
Sequence where each element is a tuple of arguments to pass to
*function*.
multiprocess : bool, optional
If `True`, use the `multiprocessing` module to distribute each
task to a different processor core.
ipython_widget : bool, optional
If `True`, the progress bar will display as an IPython
notebook widget.
file : writeable file-like object, optional
The file to write the progress bar to. Defaults to
`sys.stdout`. If ``file`` is not a tty (as determined by
calling its `isatty` member, if any), the scrollbar will
be completely silent.
step : int, optional
Update the progress bar at least every *step* steps (default: 100).
If ``multiprocess`` is `True`, this will affect the size
of the chunks of ``items`` that are submitted as separate tasks
to the process pool. A large step size may make the job
complete faster if ``items`` is very long.
"""
results = []
if file is None:
file = _get_stdout()
with cls(len(items), ipython_widget=ipython_widget, file=file) as bar:
if bar._ipython_widget:
chunksize = step
else:
default_step = max(int(float(len(items)) / bar._bar_length), 1)
chunksize = min(default_step, step)
if not multiprocess:
for i, item in enumerate(items):
results.append(function(item))
if (i % chunksize) == 0:
bar.update(i)
else:
p = multiprocessing.Pool()
for i, result in enumerate(
p.imap_unordered(function, items, chunksize=chunksize)):
bar.update(i)
results.append(result)
p.close()
p.join()
return results
class Spinner:
"""
A class to display a spinner in the terminal.
It is designed to be used with the ``with`` statement::
with Spinner("Reticulating splines", "green") as s:
for item in enumerate(items):
s.next()
"""
_default_unicode_chars = "◓◑◒◐"
_default_ascii_chars = "-/|\\"
def __init__(self, msg, color='default', file=None, step=1,
chars=None):
"""
Parameters
----------
msg : str
The message to print
color : str, optional
An ANSI terminal color name. Must be one of: black, red,
green, brown, blue, magenta, cyan, lightgrey, default,
darkgrey, lightred, lightgreen, yellow, lightblue,
lightmagenta, lightcyan, white.
file : writeable file-like object, optional
The file to write the spinner to. Defaults to
`sys.stdout`. If ``file`` is not a tty (as determined by
calling its `isatty` member, if any, or special case hacks
to detect the IPython console), the spinner will be
completely silent.
step : int, optional
Only update the spinner every *step* steps
chars : str, optional
The character sequence to use for the spinner
"""
if file is None:
file = _get_stdout()
self._msg = msg
self._color = color
self._file = file
self._step = step
if chars is None:
if conf.unicode_output:
chars = self._default_unicode_chars
else:
chars = self._default_ascii_chars
self._chars = chars
self._silent = not isatty(file)
def _iterator(self):
chars = self._chars
index = 0
file = self._file
write = file.write
flush = file.flush
try_fallback = True
while True:
write('\r')
color_print(self._msg, self._color, file=file, end='')
write(' ')
try:
if try_fallback:
write = _write_with_fallback(chars[index], write, file)
else:
write(chars[index])
except UnicodeError:
# If even _write_with_fallback failed for any reason just give
# up on trying to use the unicode characters
chars = self._default_ascii_chars
write(chars[index])
try_fallback = False # No good will come of using this again
flush()
yield
for i in range(self._step):
yield
index = (index + 1) % len(chars)
def __enter__(self):
if self._silent:
return self._silent_iterator()
else:
return self._iterator()
def __exit__(self, exc_type, exc_value, traceback):
file = self._file
write = file.write
flush = file.flush
if not self._silent:
write('\r')
color_print(self._msg, self._color, file=file, end='')
if exc_type is None:
color_print(' [Done]', 'green', file=file)
else:
color_print(' [Failed]', 'red', file=file)
flush()
def _silent_iterator(self):
color_print(self._msg, self._color, file=self._file, end='')
self._file.flush()
while True:
yield
class ProgressBarOrSpinner:
"""
A class that displays either a `ProgressBar` or `Spinner`
depending on whether the total size of the operation is
known or not.
It is designed to be used with the ``with`` statement::
if file.has_length():
length = file.get_length()
else:
length = None
bytes_read = 0
with ProgressBarOrSpinner(length) as bar:
while file.read(blocksize):
bytes_read += blocksize
bar.update(bytes_read)
"""
def __init__(self, total, msg, color='default', file=None):
"""
Parameters
----------
total : int or None
If an int, the number of increments in the process being
tracked and a `ProgressBar` is displayed. If `None`, a
`Spinner` is displayed.
msg : str
The message to display above the `ProgressBar` or
alongside the `Spinner`.
color : str, optional
The color of ``msg``, if any. Must be an ANSI terminal
color name. Must be one of: black, red, green, brown,
blue, magenta, cyan, lightgrey, default, darkgrey,
lightred, lightgreen, yellow, lightblue, lightmagenta,
lightcyan, white.
file : writable file-like object, optional
The file to write the to. Defaults to `sys.stdout`. If
``file`` is not a tty (as determined by calling its `isatty`
member, if any), only ``msg`` will be displayed: the
`ProgressBar` or `Spinner` will be silent.
"""
if file is None:
file = _get_stdout()
if total is None or not isatty(file):
self._is_spinner = True
self._obj = Spinner(msg, color=color, file=file)
else:
self._is_spinner = False
color_print(msg, color, file=file)
self._obj = ProgressBar(total, file=file)
def __enter__(self):
self._iter = self._obj.__enter__()
return self
def __exit__(self, exc_type, exc_value, traceback):
return self._obj.__exit__(exc_type, exc_value, traceback)
def update(self, value):
"""
Update the progress bar to the given value (out of the total
given to the constructor.
"""
if self._is_spinner:
next(self._iter)
else:
self._obj.update(value)
def print_code_line(line, col=None, file=None, tabwidth=8, width=70):
"""
Prints a line of source code, highlighting a particular character
position in the line. Useful for displaying the context of error
messages.
If the line is more than ``width`` characters, the line is truncated
accordingly and '…' characters are inserted at the front and/or
end.
It looks like this::
there_is_a_syntax_error_here :
^
Parameters
----------
line : unicode
The line of code to display
col : int, optional
The character in the line to highlight. ``col`` must be less
than ``len(line)``.
file : writeable file-like object, optional
Where to write to. Defaults to `sys.stdout`.
tabwidth : int, optional
The number of spaces per tab (``'\\t'``) character. Default
is 8. All tabs will be converted to spaces to ensure that the
caret lines up with the correct column.
width : int, optional
The width of the display, beyond which the line will be
truncated. Defaults to 70 (this matches the default in the
standard library's `textwrap` module).
"""
if file is None:
file = _get_stdout()
if conf.unicode_output:
ellipsis = '…'
else:
ellipsis = '...'
write = file.write
if col is not None:
if col >= len(line):
raise ValueError('col must be less the the line lenght.')
ntabs = line[:col].count('\t')
col += ntabs * (tabwidth - 1)
line = line.rstrip('\n')
line = line.replace('\t', ' ' * tabwidth)
if col is not None and col > width:
new_col = min(width // 2, len(line) - col)
offset = col - new_col
line = line[offset + len(ellipsis):]
width -= len(ellipsis)
new_col = col
col -= offset
color_print(ellipsis, 'darkgrey', file=file, end='')
if len(line) > width:
write(line[:width - len(ellipsis)])
color_print(ellipsis, 'darkgrey', file=file)
else:
write(line)
write('\n')
if col is not None:
write(' ' * col)
color_print('^', 'red', file=file)
# The following four Getch* classes implement unbuffered character reading from
# stdin on Windows, linux, MacOSX. This is taken directly from ActiveState
# Code Recipes:
# http://code.activestate.com/recipes/134892-getch-like-unbuffered-character-reading-from-stdin/
#
class Getch:
"""Get a single character from standard input without screen echo.
Returns
-------
char : str (one character)
"""
def __init__(self):
try:
self.impl = _GetchWindows()
except ImportError:
try:
self.impl = _GetchMacCarbon()
except (ImportError, AttributeError):
self.impl = _GetchUnix()
def __call__(self):
return self.impl()
class _GetchUnix:
def __init__(self):
import tty # pylint: disable=W0611
import sys # pylint: disable=W0611
# import termios now or else you'll get the Unix
# version on the Mac
import termios # pylint: disable=W0611
def __call__(self):
import sys
import tty
import termios
fd = sys.stdin.fileno()
old_settings = termios.tcgetattr(fd)
try:
tty.setraw(sys.stdin.fileno())
ch = sys.stdin.read(1)
finally:
termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
return ch
class _GetchWindows:
def __init__(self):
import msvcrt # pylint: disable=W0611
def __call__(self):
import msvcrt
return msvcrt.getch()
class _GetchMacCarbon:
"""
A function which returns the current ASCII key that is down;
if no ASCII key is down, the null string is returned. The
page http://www.mactech.com/macintosh-c/chap02-1.html was
very helpful in figuring out how to do this.
"""
def __init__(self):
import Carbon
Carbon.Evt # see if it has this (in Unix, it doesn't)
def __call__(self):
import Carbon
if Carbon.Evt.EventAvail(0x0008)[0] == 0: # 0x0008 is the keyDownMask
return ''
else:
#
# The event contains the following info:
# (what,msg,when,where,mod)=Carbon.Evt.GetNextEvent(0x0008)[1]
#
# The message (msg) contains the ASCII char which is
# extracted with the 0x000000FF charCodeMask; this
# number is converted to an ASCII character with chr() and
# returned
#
(what, msg, when, where, mod) = Carbon.Evt.GetNextEvent(0x0008)[1]
return chr(msg & 0x000000FF)
|
85f6245280a8df4012bdb07f27586dd751db6d80339023ec24fcc599c22e4947 | """
A simple class to manage a piece of global science state. See
:ref:`config-developer` for more details.
"""
__all__ = ['ScienceState']
class ScienceState:
"""
Science state subclasses are used to manage global items that can
affect science results. Subclasses will generally override
`validate` to convert from any of the acceptable inputs (such as
strings) to the appropriate internal objects, and set an initial
value to the ``_value`` member so it has a default.
Examples
--------
::
class MyState(ScienceState):
@classmethod
def validate(cls, value):
if value not in ('A', 'B', 'C'):
raise ValueError("Must be one of A, B, C")
return value
"""
def __init__(self):
raise RuntimeError(
"This class is a singleton. Do not instantiate.")
@classmethod
def get(cls):
"""
Get the current science state value.
"""
return cls.validate(cls._value)
@classmethod
def set(cls, value):
"""
Set the current science state value.
"""
class _Context:
def __init__(self, parent, value):
self._value = value
self._parent = parent
def __enter__(self):
pass
def __exit__(self, type, value, tb):
self._parent._value = self._value
def __repr__(self):
return ('<ScienceState {0}: {1!r}>'
.format(self._parent.__name__, self._parent._value))
ctx = _Context(cls, cls._value)
value = cls.validate(value)
cls._value = value
return ctx
@classmethod
def validate(cls, value):
"""
Validate the value and convert it to its native type, if
necessary.
"""
return value
|
8d1b79a6ca67012280ca4a0012f6baadded13ad5f0ae1113a37a2c250be5836d | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
A module containing specialized collection classes.
"""
class HomogeneousList(list):
"""
A subclass of list that contains only elements of a given type or
types. If an item that is not of the specified type is added to
the list, a `TypeError` is raised.
"""
def __init__(self, types, values=[]):
"""
Parameters
----------
types : sequence of types
The types to accept.
values : sequence, optional
An initial set of values.
"""
self._types = types
super().__init__()
self.extend(values)
def _assert(self, x):
if not isinstance(x, self._types):
raise TypeError(
"homogeneous list must contain only objects of "
"type '{}'".format(self._types))
def __iadd__(self, other):
self.extend(other)
return self
def __setitem__(self, idx, value):
if isinstance(idx, slice):
value = list(value)
for item in value:
self._assert(item)
else:
self._assert(value)
return super().__setitem__(idx, value)
def append(self, x):
self._assert(x)
return super().append(x)
def insert(self, i, x):
self._assert(x)
return super().insert(i, x)
def extend(self, x):
for item in x:
self._assert(item)
super().append(item)
|
299561406172ebdaa27e5487ca3ada4b24337a0b3fa538f5e69afa96afc76fc2 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""Functions related to Python runtime introspection."""
import inspect
import re
import types
import importlib
__all__ = ['resolve_name', 'minversion', 'find_current_module',
'isinstancemethod']
__doctest_skip__ = ['find_current_module']
def resolve_name(name, *additional_parts):
"""Resolve a name like ``module.object`` to an object and return it.
This ends up working like ``from module import object`` but is easier
to deal with than the `__import__` builtin and supports digging into
submodules.
Parameters
----------
name : `str`
A dotted path to a Python object--that is, the name of a function,
class, or other object in a module with the full path to that module,
including parent modules, separated by dots. Also known as the fully
qualified name of the object.
additional_parts : iterable, optional
If more than one positional arguments are given, those arguments are
automatically dotted together with ``name``.
Examples
--------
>>> resolve_name('astropy.utils.introspection.resolve_name')
<function resolve_name at 0x...>
>>> resolve_name('astropy', 'utils', 'introspection', 'resolve_name')
<function resolve_name at 0x...>
Raises
------
`ImportError`
If the module or named object is not found.
"""
additional_parts = '.'.join(additional_parts)
if additional_parts:
name = name + '.' + additional_parts
parts = name.split('.')
if len(parts) == 1:
# No dots in the name--just a straight up module import
cursor = 1
fromlist = []
else:
cursor = len(parts) - 1
fromlist = [parts[-1]]
module_name = parts[:cursor]
while cursor > 0:
try:
ret = __import__(str('.'.join(module_name)), fromlist=fromlist)
break
except ImportError:
if cursor == 0:
raise
cursor -= 1
module_name = parts[:cursor]
fromlist = [parts[cursor]]
ret = ''
for part in parts[cursor:]:
try:
ret = getattr(ret, part)
except AttributeError:
raise ImportError(name)
return ret
def minversion(module, version, inclusive=True, version_path='__version__'):
"""
Returns `True` if the specified Python module satisfies a minimum version
requirement, and `False` if not.
By default this uses `pkg_resources.parse_version` to do the version
comparison if available. Otherwise it falls back on
`distutils.version.LooseVersion`.
Parameters
----------
module : module or `str`
An imported module of which to check the version, or the name of
that module (in which case an import of that module is attempted--
if this fails `False` is returned).
version : `str`
The version as a string that this module must have at a minimum (e.g.
``'0.12'``).
inclusive : `bool`
The specified version meets the requirement inclusively (i.e. ``>=``)
as opposed to strictly greater than (default: `True`).
version_path : `str`
A dotted attribute path to follow in the module for the version.
Defaults to just ``'__version__'``, which should work for most Python
modules.
Examples
--------
>>> import astropy
>>> minversion(astropy, '0.4.4')
True
"""
if isinstance(module, types.ModuleType):
module_name = module.__name__
elif isinstance(module, str):
module_name = module
try:
module = resolve_name(module_name)
except ImportError:
return False
else:
raise ValueError('module argument must be an actual imported '
'module, or the import name of the module; '
'got {0!r}'.format(module))
if '.' not in version_path:
have_version = getattr(module, version_path)
else:
have_version = resolve_name(module.__name__, version_path)
try:
from pkg_resources import parse_version
except ImportError:
from distutils.version import LooseVersion as parse_version
# LooseVersion raises a TypeError when strings like dev, rc1 are part
# of the version number. Match the dotted numbers only. Regex taken
# from PEP440, https://www.python.org/dev/peps/pep-0440/, Appendix B
expr = '^([1-9]\\d*!)?(0|[1-9]\\d*)(\\.(0|[1-9]\\d*))*'
m = re.match(expr, version)
if m:
version = m.group(0)
if inclusive:
return parse_version(have_version) >= parse_version(version)
else:
return parse_version(have_version) > parse_version(version)
def find_current_module(depth=1, finddiff=False):
"""
Determines the module/package from which this function is called.
This function has two modes, determined by the ``finddiff`` option. it
will either simply go the requested number of frames up the call
stack (if ``finddiff`` is False), or it will go up the call stack until
it reaches a module that is *not* in a specified set.
Parameters
----------
depth : int
Specifies how far back to go in the call stack (0-indexed, so that
passing in 0 gives back `astropy.utils.misc`).
finddiff : bool or list
If False, the returned ``mod`` will just be ``depth`` frames up from
the current frame. Otherwise, the function will start at a frame
``depth`` up from current, and continue up the call stack to the
first module that is *different* from those in the provided list.
In this case, ``finddiff`` can be a list of modules or modules
names. Alternatively, it can be True, which will use the module
``depth`` call stack frames up as the module the returned module
most be different from.
Returns
-------
mod : module or None
The module object or None if the package cannot be found. The name of
the module is available as the ``__name__`` attribute of the returned
object (if it isn't None).
Raises
------
ValueError
If ``finddiff`` is a list with an invalid entry.
Examples
--------
The examples below assume that there are two modules in a package named
``pkg``. ``mod1.py``::
def find1():
from astropy.utils import find_current_module
print find_current_module(1).__name__
def find2():
from astropy.utils import find_current_module
cmod = find_current_module(2)
if cmod is None:
print 'None'
else:
print cmod.__name__
def find_diff():
from astropy.utils import find_current_module
print find_current_module(0,True).__name__
``mod2.py``::
def find():
from .mod1 import find2
find2()
With these modules in place, the following occurs::
>>> from pkg import mod1, mod2
>>> from astropy.utils import find_current_module
>>> mod1.find1()
pkg.mod1
>>> mod1.find2()
None
>>> mod2.find()
pkg.mod2
>>> find_current_module(0)
<module 'astropy.utils.misc' from 'astropy/utils/misc.py'>
>>> mod1.find_diff()
pkg.mod1
"""
frm = inspect.currentframe()
for i in range(depth):
frm = frm.f_back
if frm is None:
return None
if finddiff:
currmod = inspect.getmodule(frm)
if finddiff is True:
diffmods = [currmod]
else:
diffmods = []
for fd in finddiff:
if inspect.ismodule(fd):
diffmods.append(fd)
elif isinstance(fd, str):
diffmods.append(importlib.import_module(fd))
elif fd is True:
diffmods.append(currmod)
else:
raise ValueError('invalid entry in finddiff')
while frm:
frmb = frm.f_back
modb = inspect.getmodule(frmb)
if modb not in diffmods:
return modb
frm = frmb
else:
return inspect.getmodule(frm)
def find_mod_objs(modname, onlylocals=False):
""" Returns all the public attributes of a module referenced by name.
.. note::
The returned list *not* include subpackages or modules of
``modname``, nor does it include private attributes (those that
begin with '_' or are not in `__all__`).
Parameters
----------
modname : str
The name of the module to search.
onlylocals : bool or list of str
If `True`, only attributes that are either members of ``modname`` OR
one of its modules or subpackages will be included. If it is a list
of strings, those specify the possible packages that will be
considered "local".
Returns
-------
localnames : list of str
A list of the names of the attributes as they are named in the
module ``modname`` .
fqnames : list of str
A list of the full qualified names of the attributes (e.g.,
``astropy.utils.introspection.find_mod_objs``). For attributes that are
simple variables, this is based on the local name, but for functions or
classes it can be different if they are actually defined elsewhere and
just referenced in ``modname``.
objs : list of objects
A list of the actual attributes themselves (in the same order as
the other arguments)
"""
mod = resolve_name(modname)
if hasattr(mod, '__all__'):
pkgitems = [(k, mod.__dict__[k]) for k in mod.__all__]
else:
pkgitems = [(k, mod.__dict__[k]) for k in dir(mod) if k[0] != '_']
# filter out modules and pull the names and objs out
ismodule = inspect.ismodule
localnames = [k for k, v in pkgitems if not ismodule(v)]
objs = [v for k, v in pkgitems if not ismodule(v)]
# fully qualified names can be determined from the object's module
fqnames = []
for obj, lnm in zip(objs, localnames):
if hasattr(obj, '__module__') and hasattr(obj, '__name__'):
fqnames.append(obj.__module__ + '.' + obj.__name__)
else:
fqnames.append(modname + '.' + lnm)
if onlylocals:
if onlylocals is True:
onlylocals = [modname]
valids = [any(fqn.startswith(nm) for nm in onlylocals) for fqn in fqnames]
localnames = [e for i, e in enumerate(localnames) if valids[i]]
fqnames = [e for i, e in enumerate(fqnames) if valids[i]]
objs = [e for i, e in enumerate(objs) if valids[i]]
return localnames, fqnames, objs
# Note: I would have preferred call this is_instancemethod, but this naming is
# for consistency with other functions in the `inspect` module
def isinstancemethod(cls, obj):
"""
Returns `True` if the given object is an instance method of the class
it is defined on (as opposed to a `staticmethod` or a `classmethod`).
This requires both the class the object is a member of as well as the
object itself in order to make this determination.
Parameters
----------
cls : `type`
The class on which this method was defined.
obj : `object`
A member of the provided class (the membership is not checked directly,
but this function will always return `False` if the given object is not
a member of the given class).
Examples
--------
>>> class MetaClass(type):
... def a_classmethod(cls): pass
...
>>> class MyClass(metaclass=MetaClass):
... def an_instancemethod(self): pass
...
... @classmethod
... def another_classmethod(cls): pass
...
... @staticmethod
... def a_staticmethod(): pass
...
>>> isinstancemethod(MyClass, MyClass.a_classmethod)
False
>>> isinstancemethod(MyClass, MyClass.another_classmethod)
False
>>> isinstancemethod(MyClass, MyClass.a_staticmethod)
False
>>> isinstancemethod(MyClass, MyClass.an_instancemethod)
True
"""
return _isinstancemethod(cls, obj)
def _isinstancemethod(cls, obj):
if not isinstance(obj, types.FunctionType):
return False
# Unfortunately it seems the easiest way to get to the original
# staticmethod object is to look in the class's __dict__, though we
# also need to look up the MRO in case the method is not in the given
# class's dict
name = obj.__name__
for basecls in cls.mro(): # This includes cls
if name in basecls.__dict__:
return not isinstance(basecls.__dict__[name], staticmethod)
# This shouldn't happen, though this is the most sensible response if
# it does.
raise AttributeError(name)
|
f0a2513e77469f1f85421a4b4074485cab695e9ecb1e043354823674c7b7cab8 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""General purpose timer related functions."""
# STDLIB
import time
import warnings
from collections import Iterable, OrderedDict
from functools import partial, wraps
# THIRD-PARTY
import numpy as np
# LOCAL
from .. import units as u
from .. import log
from .. import modeling
from .exceptions import AstropyUserWarning
__all__ = ['timefunc', 'RunTimePredictor']
__doctest_skip__ = ['timefunc']
def timefunc(num_tries=1, verbose=True):
"""Decorator to time a function or method.
Parameters
----------
num_tries : int, optional
Number of calls to make. Timer will take the
average run time.
verbose : bool, optional
Extra log information.
Returns
-------
tt : float
Average run time in seconds.
result
Output(s) from the function.
Examples
--------
To add timer to time `numpy.log` for 100 times with
verbose output::
import numpy as np
from astropy.utils.timer import timefunc
@timefunc(100)
def timed_log(x):
return np.log(x)
To run the decorated function above:
>>> t, y = timed_log(100)
INFO: timed_log took 9.29832458496e-06 s on AVERAGE for 100 call(s). [...]
>>> t
9.298324584960938e-06
>>> y
4.6051701859880918
"""
def real_decorator(function):
@wraps(function)
def wrapper(*args, **kwargs):
ts = time.time()
for i in range(num_tries):
result = function(*args, **kwargs)
te = time.time()
tt = (te - ts) / num_tries
if verbose: # pragma: no cover
log.info('{0} took {1} s on AVERAGE for {2} call(s).'.format(
function.__name__, tt, num_tries))
return tt, result
return wrapper
return real_decorator
class RunTimePredictor:
"""Class to predict run time.
.. note:: Only predict for single varying numeric input parameter.
Parameters
----------
func : function
Function to time.
args : tuple
Fixed positional argument(s) for the function.
kwargs : dict
Fixed keyword argument(s) for the function.
Examples
--------
>>> from astropy.utils.timer import RunTimePredictor
Set up a predictor for :math:`10^{x}`:
>>> p = RunTimePredictor(pow, 10)
Give it baseline data to use for prediction and
get the function output values:
>>> p.time_func(range(10, 1000, 200))
>>> for input, result in sorted(p.results.items()):
... print("pow(10, {0})\\n{1}".format(input, result))
pow(10, 10)
10000000000
pow(10, 210)
10000000000...
pow(10, 410)
10000000000...
pow(10, 610)
10000000000...
pow(10, 810)
10000000000...
Fit a straight line assuming :math:`\\text{arg}^{1}` relationship
(coefficients are returned):
>>> p.do_fit() # doctest: +SKIP
array([1.16777420e-05, 1.00135803e-08])
Predict run time for :math:`10^{5000}`:
>>> p.predict_time(5000) # doctest: +SKIP
6.174564361572262e-05
Plot the prediction:
>>> p.plot(xlabeltext='Power of 10') # doctest: +SKIP
.. image:: /_static/timer_prediction_pow10.png
:width: 450px
:alt: Example plot from `astropy.utils.timer.RunTimePredictor`
When the changing argument is not the last, e.g.,
:math:`x^{2}`, something like this might work:
>>> p = RunTimePredictor(lambda x: pow(x, 2))
>>> p.time_func([2, 3, 5])
>>> sorted(p.results.items())
[(2, 4), (3, 9), (5, 25)]
"""
def __init__(self, func, *args, **kwargs):
self._funcname = func.__name__
self._pfunc = partial(func, *args, **kwargs)
self._cache_good = OrderedDict()
self._cache_bad = []
self._cache_est = OrderedDict()
self._cache_out = OrderedDict()
self._fit_func = None
self._power = None
@property
def results(self):
"""Function outputs from `time_func`.
A dictionary mapping input arguments (fixed arguments
are not included) to their respective output values.
"""
return self._cache_out
@timefunc(num_tries=1, verbose=False)
def _timed_pfunc(self, arg):
"""Run partial func once for single arg and time it."""
return self._pfunc(arg)
def _cache_time(self, arg):
"""Cache timing results without repetition."""
if arg not in self._cache_good and arg not in self._cache_bad:
try:
result = self._timed_pfunc(arg)
except Exception as e:
warnings.warn(str(e), AstropyUserWarning)
self._cache_bad.append(arg)
else:
self._cache_good[arg] = result[0] # Run time
self._cache_out[arg] = result[1] # Function output
def time_func(self, arglist):
"""Time the partial function for a list of single args
and store run time in a cache. This forms a baseline for
the prediction.
This also stores function outputs in `results`.
Parameters
----------
arglist : list of numbers
List of input arguments to time.
"""
if not isinstance(arglist, Iterable):
arglist = [arglist]
# Preserve arglist order
for arg in arglist:
self._cache_time(arg)
# FUTURE: Implement N^x * O(log(N)) fancy fitting.
def do_fit(self, model=None, fitter=None, power=1, min_datapoints=3):
"""Fit a function to the lists of arguments and
their respective run time in the cache.
By default, this does a linear least-square fitting
to a straight line on run time w.r.t. argument values
raised to the given power, and returns the optimal
intercept and slope.
Parameters
----------
model : `astropy.modeling.Model`
Model for the expected trend of run time (Y-axis)
w.r.t. :math:`\\text{arg}^{\\text{power}}` (X-axis).
If `None`, will use `~astropy.modeling.polynomial.Polynomial1D`
with ``degree=1``.
fitter : `astropy.modeling.fitting.Fitter`
Fitter for the given model to extract optimal coefficient values.
If `None`, will use `~astropy.modeling.fitting.LinearLSQFitter`.
power : int, optional
Power of values to fit.
min_datapoints : int, optional
Minimum number of data points required for fitting.
They can be built up with `time_func`.
Returns
-------
a : array-like
Fitted `~astropy.modeling.FittableModel` parameters.
Raises
------
ValueError
Insufficient data points for fitting.
ModelsError
Invalid model or fitter.
"""
# Reset related attributes
self._power = power
self._cache_est = OrderedDict()
x_arr = np.array(list(self._cache_good.keys()))
if x_arr.size < min_datapoints:
raise ValueError('requires {0} points but has {1}'.format(
min_datapoints, x_arr.size))
if model is None:
model = modeling.models.Polynomial1D(1)
elif not isinstance(model, modeling.core.Model):
raise modeling.fitting.ModelsError(
'{0} is not a model.'.format(model))
if fitter is None:
fitter = modeling.fitting.LinearLSQFitter()
elif not isinstance(fitter, modeling.fitting.Fitter):
raise modeling.fitting.ModelsError(
'{0} is not a fitter.'.format(fitter))
self._fit_func = fitter(
model, x_arr**power, list(self._cache_good.values()))
return self._fit_func.parameters
def predict_time(self, arg):
"""Predict run time for given argument.
If prediction is already cached, cached value is returned.
Parameters
----------
arg : number
Input argument to predict run time for.
Returns
-------
t_est : float
Estimated run time for given argument.
Raises
------
RuntimeError
No fitted data for prediction.
"""
if arg in self._cache_est:
t_est = self._cache_est[arg]
else:
if self._fit_func is None:
raise RuntimeError('no fitted data for prediction')
t_est = self._fit_func(arg**self._power)
self._cache_est[arg] = t_est
return t_est
def plot(self, xscale='linear', yscale='linear', xlabeltext='args',
save_as=''): # pragma: no cover
"""Plot prediction.
.. note:: Uses `matplotlib <http://matplotlib.org/>`_.
Parameters
----------
xscale, yscale : {'linear', 'log', 'symlog'}
Scaling for `matplotlib.axes.Axes`.
xlabeltext : str, optional
Text for X-label.
save_as : str, optional
Save plot as given filename.
Raises
------
RuntimeError
Insufficient data for plotting.
"""
import matplotlib.pyplot as plt
# Actual data
x_arr = sorted(self._cache_good)
y_arr = np.array([self._cache_good[x] for x in x_arr])
if len(x_arr) <= 1:
raise RuntimeError('insufficient data for plotting')
# Auto-ranging
qmean = y_arr.mean() * u.second
for cur_u in (u.minute, u.second, u.millisecond, u.microsecond,
u.nanosecond):
val = qmean.to_value(cur_u)
if 1000 > val >= 1:
break
y_arr = (y_arr * u.second).to_value(cur_u)
fig, ax = plt.subplots()
ax.plot(x_arr, y_arr, 'kx-', label='Actual')
# Fitted data
if self._fit_func is not None:
x_est = list(self._cache_est.keys())
y_est = (np.array(list(self._cache_est.values())) *
u.second).to_value(cur_u)
ax.scatter(x_est, y_est, marker='o', c='r', label='Predicted')
x_fit = np.array(sorted(x_arr + x_est))
y_fit = (self._fit_func(x_fit**self._power) *
u.second).to_value(cur_u)
ax.plot(x_fit, y_fit, 'b--', label='Fit')
ax.set_xscale(xscale)
ax.set_yscale(yscale)
ax.set_xlabel(xlabeltext)
ax.set_ylabel('Run time ({})'.format(cur_u.to_string()))
ax.set_title(self._funcname)
ax.legend(loc='best', numpoints=1)
plt.draw()
if save_as:
plt.savefig(save_as)
|
3e42210fef752e6c90b95d2593d68bc60cee14ceafff115073fc3afa4ce738d4 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module contains helper functions and classes for handling metadata.
"""
from ..utils import wraps
import warnings
import collections
from collections import OrderedDict
from copy import deepcopy
import numpy as np
from ..utils.exceptions import AstropyWarning
from ..utils.misc import dtype_bytes_or_chars
__all__ = ['MergeConflictError', 'MergeConflictWarning', 'MERGE_STRATEGIES',
'common_dtype', 'MergePlus', 'MergeNpConcatenate', 'MergeStrategy',
'MergeStrategyMeta', 'enable_merge_strategies', 'merge', 'MetaData']
class MergeConflictError(TypeError):
pass
class MergeConflictWarning(AstropyWarning):
pass
MERGE_STRATEGIES = []
def common_dtype(arrs):
"""
Use numpy to find the common dtype for a list of ndarrays.
Only allow arrays within the following fundamental numpy data types:
``np.bool_``, ``np.object_``, ``np.number``, ``np.character``, ``np.void``
Parameters
----------
arrs : list of ndarray objects
Arrays for which to find the common dtype
Returns
-------
dtype_str : str
String representation of dytpe (dtype ``str`` attribute)
"""
def dtype(arr):
return getattr(arr, 'dtype', np.dtype('O'))
np_types = (np.bool_, np.object_, np.number, np.character, np.void)
uniq_types = set(tuple(issubclass(dtype(arr).type, np_type) for np_type in np_types)
for arr in arrs)
if len(uniq_types) > 1:
# Embed into the exception the actual list of incompatible types.
incompat_types = [dtype(arr).name for arr in arrs]
tme = MergeConflictError('Arrays have incompatible types {0}'
.format(incompat_types))
tme._incompat_types = incompat_types
raise tme
arrs = [np.empty(1, dtype=dtype(arr)) for arr in arrs]
# For string-type arrays need to explicitly fill in non-zero
# values or the final arr_common = .. step is unpredictable.
for i, arr in enumerate(arrs):
if arr.dtype.kind in ('S', 'U'):
arrs[i] = [(u'0' if arr.dtype.kind == 'U' else b'0') *
dtype_bytes_or_chars(arr.dtype)]
arr_common = np.array([arr[0] for arr in arrs])
return arr_common.dtype.str
class MergeStrategyMeta(type):
"""
Metaclass that registers MergeStrategy subclasses into the
MERGE_STRATEGIES registry.
"""
def __new__(mcls, name, bases, members):
cls = super().__new__(mcls, name, bases, members)
# Wrap ``merge`` classmethod to catch any exception and re-raise as
# MergeConflictError.
if 'merge' in members and isinstance(members['merge'], classmethod):
orig_merge = members['merge'].__func__
@wraps(orig_merge)
def merge(cls, left, right):
try:
return orig_merge(cls, left, right)
except Exception as err:
raise MergeConflictError(err)
cls.merge = classmethod(merge)
# Register merging class (except for base MergeStrategy class)
if 'types' in members:
types = members['types']
if isinstance(types, tuple):
types = [types]
for left, right in reversed(types):
MERGE_STRATEGIES.insert(0, (left, right, cls))
return cls
class MergeStrategy(metaclass=MergeStrategyMeta):
"""
Base class for defining a strategy for merging metadata from two
sources, left and right, into a single output.
The primary functionality for the class is the ``merge(cls, left, right)``
class method. This takes ``left`` and ``right`` side arguments and
returns a single merged output.
The first class attribute is ``types``. This is defined as a list of
(left_types, right_types) tuples that indicate for which input types the
merge strategy applies. In determining whether to apply this merge
strategy to a pair of (left, right) objects, a test is done:
``isinstance(left, left_types) and isinstance(right, right_types)``. For
example::
types = [(np.ndarray, np.ndarray), # Two ndarrays
(np.ndarray, (list, tuple)), # ndarray and (list or tuple)
((list, tuple), np.ndarray)] # (list or tuple) and ndarray
As a convenience, ``types`` can be defined as a single two-tuple instead of
a list of two-tuples, e.g. ``types = (np.ndarray, np.ndarray)``.
The other class attribute is ``enabled``, which defaults to ``False`` in
the base class. By defining a subclass of ``MergeStrategy`` the new merge
strategy is automatically registered to be available for use in
merging. However, by default the new merge strategy is *not enabled*. This
prevents inadvertently changing the behavior of unrelated code that is
performing metadata merge operations.
In most cases (particularly in library code that others might use) it is
recommended to leave custom strategies disabled and use the
`~astropy.utils.metadata.enable_merge_strategies` context manager to locally
enable the desired strategies. However, if one is confident that the
new strategy will not produce unexpected behavior, then one can globally
enable it by setting the ``enabled`` class attribute to ``True``.
Examples
--------
Here we define a custom merge strategy that takes an int or float on
the left and right sides and returns a list with the two values.
>>> from astropy.utils.metadata import MergeStrategy
>>> class MergeNumbersAsList(MergeStrategy):
... types = ((int, float), (int, float)) # (left_types, right_types)
...
... @classmethod
... def merge(cls, left, right):
... return [left, right]
"""
# Set ``enabled = True`` to globally enable applying this merge strategy.
# This is not generally recommended.
enabled = False
# types = [(left_types, right_types), ...]
class MergePlus(MergeStrategy):
"""
Merge ``left`` and ``right`` objects using the plus operator. This
merge strategy is globally enabled by default.
"""
types = [(list, list), (tuple, tuple)]
enabled = True
@classmethod
def merge(cls, left, right):
return left + right
class MergeNpConcatenate(MergeStrategy):
"""
Merge ``left`` and ``right`` objects using np.concatenate. This
merge strategy is globally enabled by default.
This will upcast a list or tuple to np.ndarray and the output is
always ndarray.
"""
types = [(np.ndarray, np.ndarray),
(np.ndarray, (list, tuple)),
((list, tuple), np.ndarray)]
enabled = True
@classmethod
def merge(cls, left, right):
left, right = np.asanyarray(left), np.asanyarray(right)
common_dtype([left, right]) # Ensure left and right have compatible dtype
return np.concatenate([left, right])
def _both_isinstance(left, right, cls):
return isinstance(left, cls) and isinstance(right, cls)
def _not_equal(left, right):
try:
return bool(left != right)
except Exception:
return True
class _EnableMergeStrategies:
def __init__(self, *merge_strategies):
self.merge_strategies = merge_strategies
self.orig_enabled = {}
for left_type, right_type, merge_strategy in MERGE_STRATEGIES:
if issubclass(merge_strategy, merge_strategies):
self.orig_enabled[merge_strategy] = merge_strategy.enabled
merge_strategy.enabled = True
def __enter__(self):
pass
def __exit__(self, type, value, tb):
for merge_strategy, enabled in self.orig_enabled.items():
merge_strategy.enabled = enabled
def enable_merge_strategies(*merge_strategies):
"""
Context manager to temporarily enable one or more custom metadata merge
strategies.
Examples
--------
Here we define a custom merge strategy that takes an int or float on
the left and right sides and returns a list with the two values.
>>> from astropy.utils.metadata import MergeStrategy
>>> class MergeNumbersAsList(MergeStrategy):
... types = ((int, float), # left side types
... (int, float)) # right side types
... @classmethod
... def merge(cls, left, right):
... return [left, right]
By defining this class the merge strategy is automatically registered to be
available for use in merging. However, by default new merge strategies are
*not enabled*. This prevents inadvertently changing the behavior of
unrelated code that is performing metadata merge operations.
In order to use the new merge strategy, use this context manager as in the
following example::
>>> from astropy.table import Table, vstack
>>> from astropy.utils.metadata import enable_merge_strategies
>>> t1 = Table([[1]], names=['a'])
>>> t2 = Table([[2]], names=['a'])
>>> t1.meta = {'m': 1}
>>> t2.meta = {'m': 2}
>>> with enable_merge_strategies(MergeNumbersAsList):
... t12 = vstack([t1, t2])
>>> t12.meta['m']
[1, 2]
One can supply further merge strategies as additional arguments to the
context manager.
As a convenience, the enabling operation is actually done by checking
whether the registered strategies are subclasses of the context manager
arguments. This means one can define a related set of merge strategies and
then enable them all at once by enabling the base class. As a trivial
example, *all* registered merge strategies can be enabled with::
>>> with enable_merge_strategies(MergeStrategy):
... t12 = vstack([t1, t2])
Parameters
----------
merge_strategies : one or more `~astropy.utils.metadata.MergeStrategy` args
Merge strategies that will be enabled.
"""
return _EnableMergeStrategies(*merge_strategies)
def _warn_str_func(key, left, right):
out = ('Cannot merge meta key {0!r} types {1!r}'
' and {2!r}, choosing {0}={3!r}'
.format(key, type(left), type(right), right))
return out
def _error_str_func(key, left, right):
out = ('Cannot merge meta key {0!r} '
'types {1!r} and {2!r}'
.format(key, type(left), type(right)))
return out
def merge(left, right, merge_func=None, metadata_conflicts='warn',
warn_str_func=_warn_str_func,
error_str_func=_error_str_func):
"""
Merge the ``left`` and ``right`` metadata objects.
This is a simplistic and limited implementation at this point.
"""
if not _both_isinstance(left, right, dict):
raise MergeConflictError('Can only merge two dict-based objects')
out = deepcopy(left)
for key, val in right.items():
# If no conflict then insert val into out dict and continue
if key not in out:
out[key] = deepcopy(val)
continue
# There is a conflict that must be resolved
if _both_isinstance(left[key], right[key], dict):
out[key] = merge(left[key], right[key], merge_func,
metadata_conflicts=metadata_conflicts)
else:
try:
if merge_func is None:
for left_type, right_type, merge_cls in MERGE_STRATEGIES:
if not merge_cls.enabled:
continue
if (isinstance(left[key], left_type) and
isinstance(right[key], right_type)):
out[key] = merge_cls.merge(left[key], right[key])
break
else:
raise MergeConflictError
else:
out[key] = merge_func(left[key], right[key])
except MergeConflictError:
# Pick the metadata item that is not None, or they are both not
# None, then if they are equal, there is no conflict, and if
# they are different, there is a conflict and we pick the one
# on the right (or raise an error).
if left[key] is None:
# This may not seem necessary since out[key] gets set to
# right[key], but not all objects support != which is
# needed for one of the if clauses.
out[key] = right[key]
elif right[key] is None:
out[key] = left[key]
elif _not_equal(left[key], right[key]):
if metadata_conflicts == 'warn':
warnings.warn(warn_str_func(key, left[key], right[key]),
MergeConflictWarning)
elif metadata_conflicts == 'error':
raise MergeConflictError(error_str_func(key, left[key], right[key]))
elif metadata_conflicts != 'silent':
raise ValueError('metadata_conflicts argument must be one '
'of "silent", "warn", or "error"')
out[key] = right[key]
else:
out[key] = right[key]
return out
class MetaData:
"""
A descriptor for classes that have a ``meta`` property.
This can be set to any valid `~collections.Mapping`.
Parameters
----------
doc : `str`, optional
Documentation for the attribute of the class.
Default is ``""``.
.. versionadded:: 1.2
copy : `bool`, optional
If ``True`` the the value is deepcopied before setting, otherwise it
is saved as reference.
Default is ``True``.
.. versionadded:: 1.2
"""
def __init__(self, doc="", copy=True):
self.__doc__ = doc
self.copy = copy
def __get__(self, instance, owner):
if instance is None:
return self
if not hasattr(instance, '_meta'):
instance._meta = OrderedDict()
return instance._meta
def __set__(self, instance, value):
if value is None:
instance._meta = OrderedDict()
else:
if isinstance(value, collections.Mapping):
if self.copy:
instance._meta = deepcopy(value)
else:
instance._meta = value
else:
raise TypeError("meta attribute must be dict-like")
|
29f20420bd6ec82d1c540d728960eafde8f6f93b804c1dba358a234916ba7ec2 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This subpackage contains developer-oriented utilities used by Astropy.
Public functions and classes in this subpackage are safe to be used by other
packages, but this subpackage is for utilities that are primarily of use for
developers or to implement python hacks. This subpackage also includes the
`astropy.utils.compat` package, which houses utilities that provide
compatibility and bugfixes across all versions of Python that Astropy supports.
"""
from .codegen import *
from .decorators import *
from .introspection import *
from .misc import *
|
04903eb06db93262f78a0a43174eba919ef8d532cc5bbbc4597c47546d1524d0 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module contains errors/exceptions and warnings of general use for
astropy. Exceptions that are specific to a given subpackage should *not*
be here, but rather in the particular subpackage.
"""
class AstropyWarning(Warning):
"""
The base warning class from which all Astropy warnings should inherit.
Any warning inheriting from this class is handled by the Astropy logger.
"""
class AstropyUserWarning(UserWarning, AstropyWarning):
"""
The primary warning class for Astropy.
Use this if you do not need a specific sub-class.
"""
class AstropyDeprecationWarning(AstropyWarning):
"""
A warning class to indicate a deprecated feature.
"""
class AstropyPendingDeprecationWarning(PendingDeprecationWarning, AstropyWarning):
"""
A warning class to indicate a soon-to-be deprecated feature.
"""
class AstropyBackwardsIncompatibleChangeWarning(AstropyWarning):
"""
A warning class indicating a change in astropy that is incompatible
with previous versions.
The suggested procedure is to issue this warning for the version in
which the change occurs, and remove it for all following versions.
"""
class _NoValue:
"""Special keyword value.
This class may be used as the default value assigned to a
deprecated keyword in order to check if it has been given a user
defined value.
"""
def __repr__(self):
return 'astropy.utils.exceptions.NoValue'
NoValue = _NoValue()
|
5a7fce6fd927d827ce02f7cd8453b40bd564940c7c92025811a573eb798ada44 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
from distutils.core import Extension
from os.path import dirname, join, relpath
ASTROPY_UTILS_ROOT = dirname(__file__)
def get_extensions():
return [
Extension('astropy.utils._compiler',
[relpath(join(ASTROPY_UTILS_ROOT, 'src', 'compiler.c'))])
]
def get_package_data():
# Installs the testing data files
return {
'astropy.utils.tests': [
'data/test_package/*.py',
'data/test_package/data/*.txt',
'data/*.dat',
'data/*.txt',
'data/*.gz',
'data/*.bz2',
'data/*.xz',
'data/.hidden_file.txt',
'data/*.cfg'],
'astropy.utils.iers': [
'data/ReadMe.eopc04_IAU2000',
'data/ReadMe.finals2000A',
'data/eopc04_IAU2000.62-now',
'tests/finals2000A-2016-04-30-test',
'tests/finals2000A-2016-02-30-test',
'tests/iers_a_excerpt']
}
|
659133687499762bbd6380dd38c0603518b927c1959a00cb9bab05e7e2d4d538 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""This module contains functions and methods that relate to the DataInfo class
which provides a container for informational attributes as well as summary info
methods.
A DataInfo object is attached to the Quantity, SkyCoord, and Time classes in
astropy. Here it allows those classes to be used in Tables and uniformly carry
table column attributes such as name, format, dtype, meta, and description.
"""
# Note: these functions and classes are tested extensively in astropy table
# tests via their use in providing mixin column info, and in
# astropy/tests/test_info for providing table and column info summary data.
import os
import re
import sys
import weakref
import warnings
from io import StringIO
from copy import deepcopy
from functools import partial
from collections import OrderedDict
from contextlib import contextmanager
import numpy as np
from . import metadata
__all__ = ['data_info_factory', 'dtype_info_name', 'BaseColumnInfo',
'DataInfo', 'MixinInfo', 'ParentDtypeInfo']
# Tuple of filterwarnings kwargs to ignore when calling info
IGNORE_WARNINGS = (dict(category=RuntimeWarning, message='All-NaN|'
'Mean of empty slice|Degrees of freedom <= 0'),)
STRING_TYPE_NAMES = {(False, 'S'): 'str', # not PY3
(False, 'U'): 'unicode',
(True, 'S'): 'bytes', # PY3
(True, 'U'): 'str'}
@contextmanager
def serialize_context_as(context):
"""Set context for serialization.
This will allow downstream code to understand the context in which a column
is being serialized. Objects like Time or SkyCoord will have different
default serialization representations depending on context.
Parameters
----------
context : str
Context name, e.g. 'fits', 'hdf5', 'ecsv', 'yaml'
"""
old_context = BaseColumnInfo._serialize_context
BaseColumnInfo._serialize_context = context
yield
BaseColumnInfo._serialize_context = old_context
def dtype_info_name(dtype):
"""Return a human-oriented string name of the ``dtype`` arg.
This can be use by astropy methods that present type information about
a data object.
The output is mostly equivalent to ``dtype.name`` which takes the form
<type_name>[B] where <type_name> is like ``int`` or ``bool`` and [B] is an
optional number of bits which gets included only for numeric types.
For bytes, string and unicode types, the output is shown below, where <N>
is the number of characters. This representation corresponds to the Python
type that matches the dtype::
Numpy S<N> U<N>
Python bytes<N> str<N>
Parameters
----------
dtype : str, np.dtype, type
Input dtype as an object that can be converted via np.dtype()
Returns
-------
dtype_info_name : str
String name of ``dtype``
"""
dtype = np.dtype(dtype)
if dtype.kind in ('S', 'U'):
length = re.search(r'(\d+)', dtype.str).group(1)
type_name = STRING_TYPE_NAMES[(True, dtype.kind)]
out = type_name + length
else:
out = dtype.name
return out
def data_info_factory(names, funcs):
"""
Factory to create a function that can be used as an ``option``
for outputting data object summary information.
Examples
--------
>>> from astropy.utils.data_info import data_info_factory
>>> from astropy.table import Column
>>> c = Column([4., 3., 2., 1.])
>>> mystats = data_info_factory(names=['min', 'median', 'max'],
... funcs=[np.min, np.median, np.max])
>>> c.info(option=mystats)
min = 1.0
median = 2.5
max = 4.0
n_bad = 0
length = 4
Parameters
----------
names : list
List of information attribute names
funcs : list
List of functions that compute the corresponding information attribute
Returns
-------
func : function
Function that can be used as a data info option
"""
def func(dat):
outs = []
for name, func in zip(names, funcs):
try:
if isinstance(func, str):
out = getattr(dat, func)()
else:
out = func(dat)
except Exception:
outs.append('--')
else:
outs.append(str(out))
return OrderedDict(zip(names, outs))
return func
def _get_obj_attrs_map(obj, attrs):
"""
Get the values for object ``attrs`` and return as a dict. This
ignores any attributes that are None and in Py2 converts any unicode
attribute names or values to str. In the context of serializing the
supported core astropy classes this conversion will succeed and results
in more succinct and less python-specific YAML.
"""
out = {}
for attr in attrs:
val = getattr(obj, attr, None)
if val is not None:
out[attr] = val
return out
def _get_data_attribute(dat, attr=None):
"""
Get a data object attribute for the ``attributes`` info summary method
"""
if attr == 'class':
val = type(dat).__name__
elif attr == 'dtype':
val = dtype_info_name(dat.info.dtype)
elif attr == 'shape':
datshape = dat.shape[1:]
val = datshape if datshape else ''
else:
val = getattr(dat.info, attr)
if val is None:
val = ''
return str(val)
class DataInfo:
"""
Descriptor that data classes use to add an ``info`` attribute for storing
data attributes in a uniform and portable way. Note that it *must* be
called ``info`` so that the DataInfo() object can be stored in the
``instance`` using the ``info`` key. Because owner_cls.x is a descriptor,
Python doesn't use __dict__['x'] normally, and the descriptor can safely
store stuff there. Thanks to http://nbviewer.ipython.org/urls/
gist.github.com/ChrisBeaumont/5758381/raw/descriptor_writeup.ipynb for
this trick that works for non-hashable classes.
Parameters
----------
bound : bool
If True this is a descriptor attribute in a class definition, else it
is a DataInfo() object that is bound to a data object instance. Default is False.
"""
_stats = ['mean', 'std', 'min', 'max']
attrs_from_parent = set()
attr_names = set(['name', 'unit', 'dtype', 'format', 'description', 'meta'])
_attrs_no_copy = set()
_info_summary_attrs = ('dtype', 'shape', 'unit', 'format', 'description', 'class')
_represent_as_dict_attrs = ()
_parent = None
def __init__(self, bound=False):
# If bound to a data object instance then create the dict of attributes
# which stores the info attribute values.
if bound:
self._attrs = dict((attr, None) for attr in self.attr_names)
def __get__(self, instance, owner_cls):
if instance is None:
# This is an unbound descriptor on the class
info = self
info._parent_cls = owner_cls
else:
info = instance.__dict__.get('info')
if info is None:
info = instance.__dict__['info'] = self.__class__(bound=True)
info._parent = instance
return info
def __set__(self, instance, value):
if instance is None:
# This is an unbound descriptor on the class
raise ValueError('cannot set unbound descriptor')
if isinstance(value, DataInfo):
info = instance.__dict__['info'] = self.__class__(bound=True)
for attr in info.attr_names - info.attrs_from_parent - info._attrs_no_copy:
info._attrs[attr] = deepcopy(getattr(value, attr))
else:
raise TypeError('info must be set with a DataInfo instance')
def __getstate__(self):
return self._attrs
def __setstate__(self, state):
self._attrs = state
def __getattr__(self, attr):
if attr.startswith('_'):
return super().__getattribute__(attr)
if attr in self.attrs_from_parent:
return getattr(self._parent, attr)
try:
value = self._attrs[attr]
except KeyError:
super().__getattribute__(attr) # Generate AttributeError
# Weak ref for parent table
if attr == 'parent_table' and callable(value):
value = value()
# Mixins have a default dtype of Object if nothing else was set
if attr == 'dtype' and value is None:
value = np.dtype('O')
return value
def __setattr__(self, attr, value):
propobj = getattr(self.__class__, attr, None)
# If attribute is taken from parent properties and there is not a
# class property (getter/setter) for this attribute then set
# attribute directly in parent.
if attr in self.attrs_from_parent and not isinstance(propobj, property):
setattr(self._parent, attr, value)
return
# Check if there is a property setter and use it if possible.
if isinstance(propobj, property):
if propobj.fset is None:
raise AttributeError("can't set attribute")
propobj.fset(self, value)
return
# Private attr names get directly set
if attr.startswith('_'):
super().__setattr__(attr, value)
return
# Finally this must be an actual data attribute that this class is handling.
if attr not in self.attr_names:
raise AttributeError("attribute must be one of {0}".format(self.attr_names))
if attr == 'parent_table':
value = None if value is None else weakref.ref(value)
self._attrs[attr] = value
def _represent_as_dict(self):
"""Get the values for the parent ``attrs`` and return as a dict."""
return _get_obj_attrs_map(self._parent, self._represent_as_dict_attrs)
def _construct_from_dict(self, map):
return self._parent_cls(**map)
info_summary_attributes = staticmethod(
data_info_factory(names=_info_summary_attrs,
funcs=[partial(_get_data_attribute, attr=attr)
for attr in _info_summary_attrs]))
# No nan* methods in numpy < 1.8
info_summary_stats = staticmethod(
data_info_factory(names=_stats,
funcs=[getattr(np, 'nan' + stat)
for stat in _stats]))
def __call__(self, option='attributes', out=''):
"""
Write summary information about data object to the ``out`` filehandle.
By default this prints to standard output via sys.stdout.
The ``option`` argument specifies what type of information
to include. This can be a string, a function, or a list of
strings or functions. Built-in options are:
- ``attributes``: data object attributes like ``dtype`` and ``format``
- ``stats``: basic statistics: min, mean, and max
If a function is specified then that function will be called with the
data object as its single argument. The function must return an
OrderedDict containing the information attributes.
If a list is provided then the information attributes will be
appended for each of the options, in order.
Examples
--------
>>> from astropy.table import Column
>>> c = Column([1, 2], unit='m', dtype='int32')
>>> c.info()
dtype = int32
unit = m
class = Column
n_bad = 0
length = 2
>>> c.info(['attributes', 'stats'])
dtype = int32
unit = m
class = Column
mean = 1.5
std = 0.5
min = 1
max = 2
n_bad = 0
length = 2
Parameters
----------
option : str, function, list of (str or function)
Info option, defaults to 'attributes'.
out : file-like object, None
Output destination, defaults to sys.stdout. If None then the
OrderedDict with information attributes is returned
Returns
-------
info : OrderedDict if out==None else None
"""
if out == '':
out = sys.stdout
dat = self._parent
info = OrderedDict()
name = dat.info.name
if name is not None:
info['name'] = name
options = option if isinstance(option, (list, tuple)) else [option]
for option in options:
if isinstance(option, str):
if hasattr(self, 'info_summary_' + option):
option = getattr(self, 'info_summary_' + option)
else:
raise ValueError('option={0} is not an allowed information type'
.format(option))
with warnings.catch_warnings():
for ignore_kwargs in IGNORE_WARNINGS:
warnings.filterwarnings('ignore', **ignore_kwargs)
info.update(option(dat))
if hasattr(dat, 'mask'):
n_bad = np.count_nonzero(dat.mask)
else:
try:
n_bad = np.count_nonzero(np.isinf(dat) | np.isnan(dat))
except Exception:
n_bad = 0
info['n_bad'] = n_bad
try:
info['length'] = len(dat)
except TypeError:
pass
if out is None:
return info
for key, val in info.items():
if val != '':
out.write('{0} = {1}'.format(key, val) + os.linesep)
def __repr__(self):
if self._parent is None:
return super().__repr__()
out = StringIO()
self.__call__(out=out)
return out.getvalue()
class BaseColumnInfo(DataInfo):
"""
Base info class for anything that can be a column in an astropy
Table. There are at least two classes that inherit from this:
ColumnInfo: for native astropy Column / MaskedColumn objects
MixinInfo: for mixin column objects
Note that this class is defined here so that mixins can use it
without importing the table package.
"""
attr_names = DataInfo.attr_names.union(['parent_table', 'indices'])
_attrs_no_copy = set(['parent_table'])
# Context for serialization. This can be set temporarily via
# ``serialize_context_as(context)`` context manager to allow downstream
# code to understand the context in which a column is being serialized.
# Typical values are 'fits', 'hdf5', 'ecsv', 'yaml'. Objects like Time or
# SkyCoord will have different default serialization representations
# depending on context.
_serialize_context = None
def __init__(self, bound=False):
super().__init__(bound=bound)
# If bound to a data object instance then add a _format_funcs dict
# for caching functions for print formatting.
if bound:
self._format_funcs = {}
def iter_str_vals(self):
"""
This is a mixin-safe version of Column.iter_str_vals.
"""
col = self._parent
if self.parent_table is None:
from ..table.column import FORMATTER as formatter
else:
formatter = self.parent_table.formatter
_pformat_col_iter = formatter._pformat_col_iter
for str_val in _pformat_col_iter(col, -1, False, False, {}):
yield str_val
def adjust_indices(self, index, value, col_len):
'''
Adjust info indices after column modification.
Parameters
----------
index : slice, int, list, or ndarray
Element(s) of column to modify. This parameter can
be a single row number, a list of row numbers, an
ndarray of row numbers, a boolean ndarray (a mask),
or a column slice.
value : int, list, or ndarray
New value(s) to insert
col_len : int
Length of the column
'''
if not self.indices:
return
if isinstance(index, slice):
# run through each key in slice
t = index.indices(col_len)
keys = list(range(*t))
elif isinstance(index, np.ndarray) and index.dtype.kind == 'b':
# boolean mask
keys = np.where(index)[0]
else: # single int
keys = [index]
value = np.atleast_1d(value) # turn array(x) into array([x])
if value.size == 1:
# repeat single value
value = list(value) * len(keys)
for key, val in zip(keys, value):
for col_index in self.indices:
col_index.replace(key, self.name, val)
def slice_indices(self, col_slice, item, col_len):
'''
Given a sliced object, modify its indices
to correctly represent the slice.
Parameters
----------
col_slice : Column or mixin
Sliced object
item : slice, list, or ndarray
Slice used to create col_slice
col_len : int
Length of original object
'''
from ..table.sorted_array import SortedArray
if not getattr(self, '_copy_indices', True):
# Necessary because MaskedArray will perform a shallow copy
col_slice.info.indices = []
return col_slice
elif isinstance(item, slice):
col_slice.info.indices = [x[item] for x in self.indices]
elif self.indices:
if isinstance(item, np.ndarray) and item.dtype.kind == 'b':
# boolean mask
item = np.where(item)[0]
threshold = 0.6
# Empirical testing suggests that recreating a BST/RBT index is
# more effective than relabelling when less than ~60% of
# the total number of rows are involved, and is in general
# more effective for SortedArray.
small = len(item) <= 0.6 * col_len
col_slice.info.indices = []
for index in self.indices:
if small or isinstance(index, SortedArray):
new_index = index.get_slice(col_slice, item)
else:
new_index = deepcopy(index)
new_index.replace_rows(item)
col_slice.info.indices.append(new_index)
return col_slice
@staticmethod
def merge_cols_attributes(cols, metadata_conflicts, name, attrs):
"""
Utility method to merge and validate the attributes ``attrs`` for the
input table columns ``cols``.
Note that ``dtype`` and ``shape`` attributes are handled specially.
These should not be passed in ``attrs`` but will always be in the
returned dict of merged attributes.
Parameters
----------
cols : list
List of input Table column objects
metadata_conflicts : str ('warn'|'error'|'silent')
How to handle metadata conflicts
name : str
Output column name
attrs : list
List of attribute names to be merged
Returns
-------
attrs : dict of merged attributes
"""
from ..table.np_utils import TableMergeError
def warn_str_func(key, left, right):
out = ("In merged column '{}' the '{}' attribute does not match "
"({} != {}). Using {} for merged output"
.format(name, key, left, right, right))
return out
def getattrs(col):
return {attr: getattr(col.info, attr) for attr in attrs
if getattr(col.info, attr, None) is not None}
out = getattrs(cols[0])
for col in cols[1:]:
out = metadata.merge(out, getattrs(col), metadata_conflicts=metadata_conflicts,
warn_str_func=warn_str_func)
# Output dtype is the superset of all dtypes in in_cols
out['dtype'] = metadata.common_dtype(cols)
# Make sure all input shapes are the same
uniq_shapes = set(col.shape[1:] for col in cols)
if len(uniq_shapes) != 1:
raise TableMergeError('columns have different shapes')
out['shape'] = uniq_shapes.pop()
return out
class MixinInfo(BaseColumnInfo):
def __setattr__(self, attr, value):
# For mixin columns that live within a table, rename the column in the
# table when setting the name attribute. This mirrors the same
# functionality in the BaseColumn class.
if attr == 'name' and self.parent_table is not None:
from ..table.np_utils import fix_column_name
new_name = fix_column_name(value) # Ensure col name is numpy compatible
self.parent_table.columns._rename_column(self.name, new_name)
super().__setattr__(attr, value)
class ParentDtypeInfo(MixinInfo):
"""Mixin that gets info.dtype from parent"""
attrs_from_parent = set(['dtype']) # dtype and unit taken from parent
|
19aa58446b2c6841dd4f4f8893aba2ef36a8d954f0e028fc6ddb470697bf6bf2 | """Utilities and extensions for use with `argparse`."""
import os
import argparse
def directory(arg):
"""
An argument type (for use with the ``type=`` argument to
`argparse.ArgumentParser.add_argument` which determines if the argument is
an existing directory (and returns the absolute path).
"""
if not isinstance(arg, str) and os.path.isdir(arg):
raise argparse.ArgumentTypeError(
"{0} is not a directory or does not exist (the directory must "
"be created first)".format(arg))
return os.path.abspath(arg)
def readable_directory(arg):
"""
An argument type (for use with the ``type=`` argument to
`argparse.ArgumentParser.add_argument` which determines if the argument is
a directory that exists and is readable (and returns the absolute path).
"""
arg = directory(arg)
if not os.access(arg, os.R_OK):
raise argparse.ArgumentTypeError(
"{0} exists but is not readable with its current "
"permissions".format(arg))
return arg
def writeable_directory(arg):
"""
An argument type (for use with the ``type=`` argument to
`argparse.ArgumentParser.add_argument` which determines if the argument is
a directory that exists and is writeable (and returns the absolute path).
"""
arg = directory(arg)
if not os.access(arg, os.W_OK):
raise argparse.ArgumentTypeError(
"{0} exists but is not writeable with its current "
"permissions".format(arg))
return arg
|
9fcdc3b66a27bf11054bb5a90bcda555580b3f2eb78c4243c53df66d371daecc | # Licensed under a 3-clause BSD style license - see LICENSE.rst
""" This module contains helper functions for accessing, downloading, and
caching data files.
"""
import atexit
import contextlib
import fnmatch
import hashlib
import os
import io
import pathlib
import shutil
import socket
import sys
import time
import urllib.request
import urllib.error
import urllib.parse
import shelve
from tempfile import NamedTemporaryFile, gettempdir
from warnings import warn
from .. import config as _config
from ..utils.exceptions import AstropyWarning
from ..utils.introspection import find_current_module, resolve_name
__all__ = [
'Conf', 'conf', 'get_readable_fileobj', 'get_file_contents',
'get_pkg_data_fileobj', 'get_pkg_data_filename',
'get_pkg_data_contents', 'get_pkg_data_fileobjs',
'get_pkg_data_filenames', 'compute_hash', 'clear_download_cache',
'CacheMissingWarning', 'get_free_space_in_dir',
'check_free_space_in_dir', 'download_file',
'download_files_in_parallel', 'is_url_in_cache', 'get_cached_urls']
_dataurls_to_alias = {}
class Conf(_config.ConfigNamespace):
"""
Configuration parameters for `astropy.utils.data`.
"""
dataurl = _config.ConfigItem(
'http://data.astropy.org/',
'Primary URL for astropy remote data site.')
dataurl_mirror = _config.ConfigItem(
'http://www.astropy.org/astropy-data/',
'Mirror URL for astropy remote data site.')
remote_timeout = _config.ConfigItem(
10.,
'Time to wait for remote data queries (in seconds).',
aliases=['astropy.coordinates.name_resolve.name_resolve_timeout'])
compute_hash_block_size = _config.ConfigItem(
2 ** 16, # 64K
'Block size for computing MD5 file hashes.')
download_block_size = _config.ConfigItem(
2 ** 16, # 64K
'Number of bytes of remote data to download per step.')
download_cache_lock_attempts = _config.ConfigItem(
5,
'Number of times to try to get the lock ' +
'while accessing the data cache before giving up.')
delete_temporary_downloads_at_exit = _config.ConfigItem(
True,
'If True, temporary download files created when the cache is '
'inaccessible will be deleted at the end of the python session.')
conf = Conf()
class CacheMissingWarning(AstropyWarning):
"""
This warning indicates the standard cache directory is not accessible, with
the first argument providing the warning message. If args[1] is present, it
is a filename indicating the path to a temporary file that was created to
store a remote data download in the absence of the cache.
"""
def _is_url(string):
"""
Test whether a string is a valid URL
Parameters
----------
string : str
The string to test
"""
url = urllib.parse.urlparse(string)
# we can't just check that url.scheme is not an empty string, because
# file paths in windows would return a non-empty scheme (e.g. e:\\
# returns 'e').
return url.scheme.lower() in ['http', 'https', 'ftp', 'sftp', 'ssh', 'file']
def _is_inside(path, parent_path):
# We have to try realpath too to avoid issues with symlinks, but we leave
# abspath because some systems like debian have the absolute path (with no
# symlinks followed) match, but the real directories in different
# locations, so need to try both cases.
return os.path.abspath(path).startswith(os.path.abspath(parent_path)) \
or os.path.realpath(path).startswith(os.path.realpath(parent_path))
@contextlib.contextmanager
def get_readable_fileobj(name_or_obj, encoding=None, cache=False,
show_progress=True, remote_timeout=None):
"""
Given a filename, pathlib.Path object or a readable file-like object, return a context
manager that yields a readable file-like object.
This supports passing filenames, URLs, and readable file-like objects,
any of which can be compressed in gzip, bzip2 or lzma (xz) if the
appropriate compression libraries are provided by the Python installation.
Notes
-----
This function is a context manager, and should be used for example
as::
with get_readable_fileobj('file.dat') as f:
contents = f.read()
Parameters
----------
name_or_obj : str or file-like object
The filename of the file to access (if given as a string), or
the file-like object to access.
If a file-like object, it must be opened in binary mode.
encoding : str, optional
When `None` (default), returns a file-like object with a
``read`` method that returns `str` (``unicode``) objects, using
`locale.getpreferredencoding` as an encoding. This matches
the default behavior of the built-in `open` when no ``mode``
argument is provided.
When ``'binary'``, returns a file-like object where its ``read``
method returns `bytes` objects.
When another string, it is the name of an encoding, and the
file-like object's ``read`` method will return `str` (``unicode``)
objects, decoded from binary using the given encoding.
cache : bool, optional
Whether to cache the contents of remote URLs.
show_progress : bool, optional
Whether to display a progress bar if the file is downloaded
from a remote server. Default is `True`.
remote_timeout : float
Timeout for remote requests in seconds (default is the configurable
`astropy.utils.data.Conf.remote_timeout`, which is 3s by default)
Returns
-------
file : readable file-like object
"""
# close_fds is a list of file handles created by this function
# that need to be closed. We don't want to always just close the
# returned file handle, because it may simply be the file handle
# passed in. In that case it is not the responsibility of this
# function to close it: doing so could result in a "double close"
# and an "invalid file descriptor" exception.
PATH_TYPES = (str, pathlib.Path)
close_fds = []
delete_fds = []
if remote_timeout is None:
# use configfile default
remote_timeout = conf.remote_timeout
# Get a file object to the content
if isinstance(name_or_obj, PATH_TYPES):
# name_or_obj could be a Path object if pathlib is available
name_or_obj = str(name_or_obj)
is_url = _is_url(name_or_obj)
if is_url:
name_or_obj = download_file(
name_or_obj, cache=cache, show_progress=show_progress,
timeout=remote_timeout)
fileobj = io.FileIO(name_or_obj, 'r')
if is_url and not cache:
delete_fds.append(fileobj)
close_fds.append(fileobj)
else:
fileobj = name_or_obj
# Check if the file object supports random access, and if not,
# then wrap it in a BytesIO buffer. It would be nicer to use a
# BufferedReader to avoid reading loading the whole file first,
# but that is not compatible with streams or urllib2.urlopen
# objects on Python 2.x.
if not hasattr(fileobj, 'seek'):
fileobj = io.BytesIO(fileobj.read())
# Now read enough bytes to look at signature
signature = fileobj.read(4)
fileobj.seek(0)
if signature[:3] == b'\x1f\x8b\x08': # gzip
import struct
try:
import gzip
fileobj_new = gzip.GzipFile(fileobj=fileobj, mode='rb')
fileobj_new.read(1) # need to check that the file is really gzip
except (OSError, EOFError, struct.error): # invalid gzip file
fileobj.seek(0)
fileobj_new.close()
else:
fileobj_new.seek(0)
fileobj = fileobj_new
elif signature[:3] == b'BZh': # bzip2
try:
import bz2
except ImportError:
for fd in close_fds:
fd.close()
raise ValueError(
".bz2 format files are not supported since the Python "
"interpreter does not include the bz2 module")
try:
# bz2.BZ2File does not support file objects, only filenames, so we
# need to write the data to a temporary file
with NamedTemporaryFile("wb", delete=False) as tmp:
tmp.write(fileobj.read())
tmp.close()
fileobj_new = bz2.BZ2File(tmp.name, mode='rb')
fileobj_new.read(1) # need to check that the file is really bzip2
except OSError: # invalid bzip2 file
fileobj.seek(0)
fileobj_new.close()
# raise
else:
fileobj_new.seek(0)
close_fds.append(fileobj_new)
fileobj = fileobj_new
elif signature[:3] == b'\xfd7z': # xz
try:
import lzma
fileobj_new = lzma.LZMAFile(fileobj, mode='rb')
fileobj_new.read(1) # need to check that the file is really xz
except ImportError:
for fd in close_fds:
fd.close()
raise ValueError(
".xz format files are not supported since the Python "
"interpreter does not include the lzma module.")
except (OSError, EOFError) as e: # invalid xz file
fileobj.seek(0)
fileobj_new.close()
# should we propagate this to the caller to signal bad content?
# raise ValueError(e)
else:
fileobj_new.seek(0)
fileobj = fileobj_new
# By this point, we have a file, io.FileIO, gzip.GzipFile, bz2.BZ2File
# or lzma.LZMAFile instance opened in binary mode (that is, read
# returns bytes). Now we need to, if requested, wrap it in a
# io.TextIOWrapper so read will return unicode based on the
# encoding parameter.
needs_textio_wrapper = encoding != 'binary'
if needs_textio_wrapper:
# A bz2.BZ2File can not be wrapped by a TextIOWrapper,
# so we decompress it to a temporary file and then
# return a handle to that.
try:
import bz2
except ImportError:
pass
else:
if isinstance(fileobj, bz2.BZ2File):
tmp = NamedTemporaryFile("wb", delete=False)
data = fileobj.read()
tmp.write(data)
tmp.close()
delete_fds.append(tmp)
fileobj = io.FileIO(tmp.name, 'r')
close_fds.append(fileobj)
fileobj = io.BufferedReader(fileobj)
fileobj = io.TextIOWrapper(fileobj, encoding=encoding)
# Ensure that file is at the start - io.FileIO will for
# example not always be at the start:
# >>> import io
# >>> f = open('test.fits', 'rb')
# >>> f.read(4)
# 'SIMP'
# >>> f.seek(0)
# >>> fileobj = io.FileIO(f.fileno())
# >>> fileobj.tell()
# 4096L
fileobj.seek(0)
try:
yield fileobj
finally:
for fd in close_fds:
fd.close()
for fd in delete_fds:
os.remove(fd.name)
def get_file_contents(*args, **kwargs):
"""
Retrieves the contents of a filename or file-like object.
See the `get_readable_fileobj` docstring for details on parameters.
Returns
-------
content
The content of the file (as requested by ``encoding``).
"""
with get_readable_fileobj(*args, **kwargs) as f:
return f.read()
@contextlib.contextmanager
def get_pkg_data_fileobj(data_name, package=None, encoding=None, cache=True):
"""
Retrieves a data file from the standard locations for the package and
provides the file as a file-like object that reads bytes.
Parameters
----------
data_name : str
Name/location of the desired data file. One of the following:
* The name of a data file included in the source
distribution. The path is relative to the module
calling this function. For example, if calling from
``astropy.pkname``, use ``'data/file.dat'`` to get the
file in ``astropy/pkgname/data/file.dat``. Double-dots
can be used to go up a level. In the same example, use
``'../data/file.dat'`` to get ``astropy/data/file.dat``.
* If a matching local file does not exist, the Astropy
data server will be queried for the file.
* A hash like that produced by `compute_hash` can be
requested, prefixed by 'hash/'
e.g. 'hash/34c33b3eb0d56eb9462003af249eff28'. The hash
will first be searched for locally, and if not found,
the Astropy data server will be queried.
package : str, optional
If specified, look for a file relative to the given package, rather
than the default of looking relative to the calling module's package.
encoding : str, optional
When `None` (default), returns a file-like object with a
``read`` method returns `str` (``unicode``) objects, using
`locale.getpreferredencoding` as an encoding. This matches
the default behavior of the built-in `open` when no ``mode``
argument is provided.
When ``'binary'``, returns a file-like object where its ``read``
method returns `bytes` objects.
When another string, it is the name of an encoding, and the
file-like object's ``read`` method will return `str` (``unicode``)
objects, decoded from binary using the given encoding.
cache : bool
If True, the file will be downloaded and saved locally or the
already-cached local copy will be accessed. If False, the
file-like object will directly access the resource (e.g. if a
remote URL is accessed, an object like that from
`urllib.request.urlopen` is returned).
Returns
-------
fileobj : file-like
An object with the contents of the data file available via
``read`` function. Can be used as part of a ``with`` statement,
automatically closing itself after the ``with`` block.
Raises
------
urllib2.URLError, urllib.error.URLError
If a remote file cannot be found.
OSError
If problems occur writing or reading a local file.
Examples
--------
This will retrieve a data file and its contents for the `astropy.wcs`
tests::
>>> from astropy.utils.data import get_pkg_data_fileobj
>>> with get_pkg_data_fileobj('data/3d_cd.hdr',
... package='astropy.wcs.tests') as fobj:
... fcontents = fobj.read()
...
This next example would download a data file from the astropy data server
because the ``allsky/allsky_rosat.fits`` file is not present in the
source distribution. It will also save the file locally so the
next time it is accessed it won't need to be downloaded.::
>>> from astropy.utils.data import get_pkg_data_fileobj
>>> with get_pkg_data_fileobj('allsky/allsky_rosat.fits',
... encoding='binary') as fobj: # doctest: +REMOTE_DATA
... fcontents = fobj.read()
...
Downloading http://data.astropy.org/allsky/allsky_rosat.fits [Done]
This does the same thing but does *not* cache it locally::
>>> with get_pkg_data_fileobj('allsky/allsky_rosat.fits',
... encoding='binary', cache=False) as fobj: # doctest: +REMOTE_DATA
... fcontents = fobj.read()
...
Downloading http://data.astropy.org/allsky/allsky_rosat.fits [Done]
See Also
--------
get_pkg_data_contents : returns the contents of a file or url as a bytes object
get_pkg_data_filename : returns a local name for a file containing the data
"""
datafn = _find_pkg_data_path(data_name, package=package)
if os.path.isdir(datafn):
raise OSError("Tried to access a data file that's actually "
"a package data directory")
elif os.path.isfile(datafn): # local file
with get_readable_fileobj(datafn, encoding=encoding) as fileobj:
yield fileobj
else: # remote file
all_urls = (conf.dataurl, conf.dataurl_mirror)
for url in all_urls:
try:
with get_readable_fileobj(url + data_name, encoding=encoding,
cache=cache) as fileobj:
# We read a byte to trigger any URLErrors
fileobj.read(1)
fileobj.seek(0)
yield fileobj
break
except urllib.error.URLError:
pass
else:
urls = '\n'.join(' - {0}'.format(url) for url in all_urls)
raise urllib.error.URLError("Failed to download {0} from the following "
"repositories:\n\n{1}".format(data_name, urls))
def get_pkg_data_filename(data_name, package=None, show_progress=True,
remote_timeout=None):
"""
Retrieves a data file from the standard locations for the package and
provides a local filename for the data.
This function is similar to `get_pkg_data_fileobj` but returns the
file *name* instead of a readable file-like object. This means
that this function must always cache remote files locally, unlike
`get_pkg_data_fileobj`.
Parameters
----------
data_name : str
Name/location of the desired data file. One of the following:
* The name of a data file included in the source
distribution. The path is relative to the module
calling this function. For example, if calling from
``astropy.pkname``, use ``'data/file.dat'`` to get the
file in ``astropy/pkgname/data/file.dat``. Double-dots
can be used to go up a level. In the same example, use
``'../data/file.dat'`` to get ``astropy/data/file.dat``.
* If a matching local file does not exist, the Astropy
data server will be queried for the file.
* A hash like that produced by `compute_hash` can be
requested, prefixed by 'hash/'
e.g. 'hash/34c33b3eb0d56eb9462003af249eff28'. The hash
will first be searched for locally, and if not found,
the Astropy data server will be queried.
package : str, optional
If specified, look for a file relative to the given package, rather
than the default of looking relative to the calling module's package.
show_progress : bool, optional
Whether to display a progress bar if the file is downloaded
from a remote server. Default is `True`.
remote_timeout : float
Timeout for the requests in seconds (default is the
configurable `astropy.utils.data.Conf.remote_timeout`, which
is 3s by default)
Raises
------
urllib2.URLError, urllib.error.URLError
If a remote file cannot be found.
OSError
If problems occur writing or reading a local file.
Returns
-------
filename : str
A file path on the local file system corresponding to the data
requested in ``data_name``.
Examples
--------
This will retrieve the contents of the data file for the `astropy.wcs`
tests::
>>> from astropy.utils.data import get_pkg_data_filename
>>> fn = get_pkg_data_filename('data/3d_cd.hdr',
... package='astropy.wcs.tests')
>>> with open(fn) as f:
... fcontents = f.read()
...
This retrieves a data file by hash either locally or from the astropy data
server::
>>> from astropy.utils.data import get_pkg_data_filename
>>> fn = get_pkg_data_filename('hash/34c33b3eb0d56eb9462003af249eff28') # doctest: +SKIP
>>> with open(fn) as f:
... fcontents = f.read()
...
See Also
--------
get_pkg_data_contents : returns the contents of a file or url as a bytes object
get_pkg_data_fileobj : returns a file-like object with the data
"""
if remote_timeout is None:
# use configfile default
remote_timeout = conf.remote_timeout
if data_name.startswith('hash/'):
# first try looking for a local version if a hash is specified
hashfn = _find_hash_fn(data_name[5:])
if hashfn is None:
all_urls = (conf.dataurl, conf.dataurl_mirror)
for url in all_urls:
try:
return download_file(url + data_name, cache=True,
show_progress=show_progress,
timeout=remote_timeout)
except urllib.error.URLError:
pass
urls = '\n'.join(' - {0}'.format(url) for url in all_urls)
raise urllib.error.URLError("Failed to download {0} from the following "
"repositories:\n\n{1}\n\n".format(data_name, urls))
else:
return hashfn
else:
fs_path = os.path.normpath(data_name)
datafn = _find_pkg_data_path(fs_path, package=package)
if os.path.isdir(datafn):
raise OSError("Tried to access a data file that's actually "
"a package data directory")
elif os.path.isfile(datafn): # local file
return datafn
else: # remote file
all_urls = (conf.dataurl, conf.dataurl_mirror)
for url in all_urls:
try:
return download_file(url + data_name, cache=True,
show_progress=show_progress,
timeout=remote_timeout)
except urllib.error.URLError:
pass
urls = '\n'.join(' - {0}'.format(url) for url in all_urls)
raise urllib.error.URLError("Failed to download {0} from the following "
"repositories:\n\n{1}".format(data_name, urls))
def get_pkg_data_contents(data_name, package=None, encoding=None, cache=True):
"""
Retrieves a data file from the standard locations and returns its
contents as a bytes object.
Parameters
----------
data_name : str
Name/location of the desired data file. One of the following:
* The name of a data file included in the source
distribution. The path is relative to the module
calling this function. For example, if calling from
``astropy.pkname``, use ``'data/file.dat'`` to get the
file in ``astropy/pkgname/data/file.dat``. Double-dots
can be used to go up a level. In the same example, use
``'../data/file.dat'`` to get ``astropy/data/file.dat``.
* If a matching local file does not exist, the Astropy
data server will be queried for the file.
* A hash like that produced by `compute_hash` can be
requested, prefixed by 'hash/'
e.g. 'hash/34c33b3eb0d56eb9462003af249eff28'. The hash
will first be searched for locally, and if not found,
the Astropy data server will be queried.
* A URL to some other file.
package : str, optional
If specified, look for a file relative to the given package, rather
than the default of looking relative to the calling module's package.
encoding : str, optional
When `None` (default), returns a file-like object with a
``read`` method that returns `str` (``unicode``) objects, using
`locale.getpreferredencoding` as an encoding. This matches
the default behavior of the built-in `open` when no ``mode``
argument is provided.
When ``'binary'``, returns a file-like object where its ``read``
method returns `bytes` objects.
When another string, it is the name of an encoding, and the
file-like object's ``read`` method will return `str` (``unicode``)
objects, decoded from binary using the given encoding.
cache : bool
If True, the file will be downloaded and saved locally or the
already-cached local copy will be accessed. If False, the
file-like object will directly access the resource (e.g. if a
remote URL is accessed, an object like that from
`urllib.request.urlopen` is returned).
Returns
-------
contents : bytes
The complete contents of the file as a bytes object.
Raises
------
urllib2.URLError, urllib.error.URLError
If a remote file cannot be found.
OSError
If problems occur writing or reading a local file.
See Also
--------
get_pkg_data_fileobj : returns a file-like object with the data
get_pkg_data_filename : returns a local name for a file containing the data
"""
with get_pkg_data_fileobj(data_name, package=package, encoding=encoding,
cache=cache) as fd:
contents = fd.read()
return contents
def get_pkg_data_filenames(datadir, package=None, pattern='*'):
"""
Returns the path of all of the data files in a given directory
that match a given glob pattern.
Parameters
----------
datadir : str
Name/location of the desired data files. One of the following:
* The name of a directory included in the source
distribution. The path is relative to the module
calling this function. For example, if calling from
``astropy.pkname``, use ``'data'`` to get the
files in ``astropy/pkgname/data``.
* Remote URLs are not currently supported.
package : str, optional
If specified, look for a file relative to the given package, rather
than the default of looking relative to the calling module's package.
pattern : str, optional
A UNIX-style filename glob pattern to match files. See the
`glob` module in the standard library for more information.
By default, matches all files.
Returns
-------
filenames : iterator of str
Paths on the local filesystem in *datadir* matching *pattern*.
Examples
--------
This will retrieve the contents of the data file for the `astropy.wcs`
tests::
>>> from astropy.utils.data import get_pkg_data_filenames
>>> for fn in get_pkg_data_filenames('maps', 'astropy.wcs.tests',
... '*.hdr'):
... with open(fn) as f:
... fcontents = f.read()
...
"""
path = _find_pkg_data_path(datadir, package=package)
if os.path.isfile(path):
raise OSError(
"Tried to access a data directory that's actually "
"a package data file")
elif os.path.isdir(path):
for filename in os.listdir(path):
if fnmatch.fnmatch(filename, pattern):
yield os.path.join(path, filename)
else:
raise OSError("Path not found")
def get_pkg_data_fileobjs(datadir, package=None, pattern='*', encoding=None):
"""
Returns readable file objects for all of the data files in a given
directory that match a given glob pattern.
Parameters
----------
datadir : str
Name/location of the desired data files. One of the following:
* The name of a directory included in the source
distribution. The path is relative to the module
calling this function. For example, if calling from
``astropy.pkname``, use ``'data'`` to get the
files in ``astropy/pkgname/data``
* Remote URLs are not currently supported
package : str, optional
If specified, look for a file relative to the given package, rather
than the default of looking relative to the calling module's package.
pattern : str, optional
A UNIX-style filename glob pattern to match files. See the
`glob` module in the standard library for more information.
By default, matches all files.
encoding : str, optional
When `None` (default), returns a file-like object with a
``read`` method that returns `str` (``unicode``) objects, using
`locale.getpreferredencoding` as an encoding. This matches
the default behavior of the built-in `open` when no ``mode``
argument is provided.
When ``'binary'``, returns a file-like object where its ``read``
method returns `bytes` objects.
When another string, it is the name of an encoding, and the
file-like object's ``read`` method will return `str` (``unicode``)
objects, decoded from binary using the given encoding.
Returns
-------
fileobjs : iterator of file objects
File objects for each of the files on the local filesystem in
*datadir* matching *pattern*.
Examples
--------
This will retrieve the contents of the data file for the `astropy.wcs`
tests::
>>> from astropy.utils.data import get_pkg_data_filenames
>>> for fd in get_pkg_data_fileobjs('maps', 'astropy.wcs.tests',
... '*.hdr'):
... fcontents = fd.read()
...
"""
for fn in get_pkg_data_filenames(datadir, package=package,
pattern=pattern):
with get_readable_fileobj(fn, encoding=encoding) as fd:
yield fd
def compute_hash(localfn):
""" Computes the MD5 hash for a file.
The hash for a data file is used for looking up data files in a unique
fashion. This is of particular use for tests; a test may require a
particular version of a particular file, in which case it can be accessed
via hash to get the appropriate version.
Typically, if you wish to write a test that requires a particular data
file, you will want to submit that file to the astropy data servers, and
use
e.g. ``get_pkg_data_filename('hash/34c33b3eb0d56eb9462003af249eff28')``,
but with the hash for your file in place of the hash in the example.
Parameters
----------
localfn : str
The path to the file for which the hash should be generated.
Returns
-------
md5hash : str
The hex digest of the MD5 hash for the contents of the ``localfn``
file.
"""
with open(localfn, 'rb') as f:
h = hashlib.md5()
block = f.read(conf.compute_hash_block_size)
while block:
h.update(block)
block = f.read(conf.compute_hash_block_size)
return h.hexdigest()
def _find_pkg_data_path(data_name, package=None):
"""
Look for data in the source-included data directories and return the
path.
"""
if package is None:
module = find_current_module(1, finddiff=['astropy.utils.data', 'contextlib'])
if module is None:
# not called from inside an astropy package. So just pass name
# through
return data_name
if not hasattr(module, '__package__') or not module.__package__:
# The __package__ attribute may be missing or set to None; see
# PEP-366, also astropy issue #1256
if '.' in module.__name__:
package = module.__name__.rpartition('.')[0]
else:
package = module.__name__
else:
package = module.__package__
else:
module = resolve_name(package)
rootpkgname = package.partition('.')[0]
rootpkg = resolve_name(rootpkgname)
module_path = os.path.dirname(module.__file__)
path = os.path.join(module_path, data_name)
root_dir = os.path.dirname(rootpkg.__file__)
if not _is_inside(path, root_dir):
raise RuntimeError("attempted to get a local data file outside "
"of the {} tree.".format(rootpkgname))
return path
def _find_hash_fn(hash):
"""
Looks for a local file by hash - returns file name if found and a valid
file, otherwise returns None.
"""
try:
dldir, urlmapfn = _get_download_cache_locs()
except OSError as e:
msg = 'Could not access cache directory to search for data file: '
warn(CacheMissingWarning(msg + str(e)))
return None
hashfn = os.path.join(dldir, hash)
if os.path.isfile(hashfn):
return hashfn
else:
return None
def get_free_space_in_dir(path):
"""
Given a path to a directory, returns the amount of free space (in
bytes) on that filesystem.
Parameters
----------
path : str
The path to a directory
Returns
-------
bytes : int
The amount of free space on the partition that the directory
is on.
"""
if sys.platform.startswith('win'):
import ctypes
free_bytes = ctypes.c_ulonglong(0)
retval = ctypes.windll.kernel32.GetDiskFreeSpaceExW(
ctypes.c_wchar_p(path), None, None, ctypes.pointer(free_bytes))
if retval == 0:
raise OSError('Checking free space on {!r} failed '
'unexpectedly.'.format(path))
return free_bytes.value
else:
stat = os.statvfs(path)
return stat.f_bavail * stat.f_frsize
def check_free_space_in_dir(path, size):
"""
Determines if a given directory has enough space to hold a file of
a given size. Raises an OSError if the file would be too large.
Parameters
----------
path : str
The path to a directory
size : int
A proposed filesize (in bytes)
Raises
-------
OSError : There is not enough room on the filesystem
"""
from ..utils.console import human_file_size
space = get_free_space_in_dir(path)
if space < size:
raise OSError(
"Not enough free space in '{0}' "
"to download a {1} file".format(
path, human_file_size(size)))
def download_file(remote_url, cache=False, show_progress=True, timeout=None):
"""
Accepts a URL, downloads and optionally caches the result
returning the filename, with a name determined by the file's MD5
hash. If ``cache=True`` and the file is present in the cache, just
returns the filename.
Parameters
----------
remote_url : str
The URL of the file to download
cache : bool, optional
Whether to use the cache
show_progress : bool, optional
Whether to display a progress bar during the download (default
is `True`)
timeout : float, optional
The timeout, in seconds. Otherwise, use
`astropy.utils.data.Conf.remote_timeout`.
Returns
-------
local_path : str
Returns the local path that the file was download to.
Raises
------
urllib2.URLError, urllib.error.URLError
Whenever there's a problem getting the remote file.
"""
from ..utils.console import ProgressBarOrSpinner
if timeout is None:
timeout = conf.remote_timeout
missing_cache = False
if cache:
try:
dldir, urlmapfn = _get_download_cache_locs()
except OSError as e:
msg = 'Remote data cache could not be accessed due to '
estr = '' if len(e.args) < 1 else (': ' + str(e))
warn(CacheMissingWarning(msg + e.__class__.__name__ + estr))
cache = False
missing_cache = True # indicates that the cache is missing to raise a warning later
url_key = remote_url
# Check if URL is Astropy data server, which has alias, and cache it.
if (url_key.startswith(conf.dataurl) and
conf.dataurl not in _dataurls_to_alias):
with urllib.request.urlopen(conf.dataurl, timeout=timeout) as remote:
_dataurls_to_alias[conf.dataurl] = [conf.dataurl, remote.geturl()]
try:
if cache:
# We don't need to acquire the lock here, since we are only reading
with shelve.open(urlmapfn) as url2hash:
if url_key in url2hash:
return url2hash[url_key]
# If there is a cached copy from mirror, use it.
else:
for cur_url in _dataurls_to_alias.get(conf.dataurl, []):
if url_key.startswith(cur_url):
url_mirror = url_key.replace(cur_url,
conf.dataurl_mirror)
if url_mirror in url2hash:
return url2hash[url_mirror]
with urllib.request.urlopen(remote_url, timeout=timeout) as remote:
# keep a hash to rename the local file to the hashed name
hash = hashlib.md5()
info = remote.info()
if 'Content-Length' in info:
try:
size = int(info['Content-Length'])
except ValueError:
size = None
else:
size = None
if size is not None:
check_free_space_in_dir(gettempdir(), size)
if cache:
check_free_space_in_dir(dldir, size)
if show_progress:
progress_stream = sys.stdout
else:
progress_stream = io.StringIO()
dlmsg = "Downloading {0}".format(remote_url)
with ProgressBarOrSpinner(size, dlmsg, file=progress_stream) as p:
with NamedTemporaryFile(delete=False) as f:
try:
bytes_read = 0
block = remote.read(conf.download_block_size)
while block:
f.write(block)
hash.update(block)
bytes_read += len(block)
p.update(bytes_read)
block = remote.read(conf.download_block_size)
except BaseException:
if os.path.exists(f.name):
os.remove(f.name)
raise
if cache:
_acquire_download_cache_lock()
try:
with shelve.open(urlmapfn) as url2hash:
# We check now to see if another process has
# inadvertently written the file underneath us
# already
if url_key in url2hash:
return url2hash[url_key]
local_path = os.path.join(dldir, hash.hexdigest())
shutil.move(f.name, local_path)
url2hash[url_key] = local_path
finally:
_release_download_cache_lock()
else:
local_path = f.name
if missing_cache:
msg = ('File downloaded to temporary location due to problem '
'with cache directory and will not be cached.')
warn(CacheMissingWarning(msg, local_path))
if conf.delete_temporary_downloads_at_exit:
global _tempfilestodel
_tempfilestodel.append(local_path)
except urllib.error.URLError as e:
if hasattr(e, 'reason') and hasattr(e.reason, 'errno') and e.reason.errno == 8:
e.reason.strerror = e.reason.strerror + '. requested URL: ' + remote_url
e.reason.args = (e.reason.errno, e.reason.strerror)
raise e
except socket.timeout as e:
# this isn't supposed to happen, but occasionally a socket.timeout gets
# through. It's supposed to be caught in `urrlib2` and raised in this
# way, but for some reason in mysterious circumstances it doesn't. So
# we'll just re-raise it here instead
raise urllib.error.URLError(e)
return local_path
def is_url_in_cache(url_key):
"""
Check if a download from ``url_key`` is in the cache.
Parameters
----------
url_key : string
The URL retrieved
Returns
-------
in_cache : bool
`True` if a download from ``url_key`` is in the cache
"""
# The code below is modified from astropy.utils.data.download_file()
try:
dldir, urlmapfn = _get_download_cache_locs()
except OSError as e:
msg = 'Remote data cache could not be accessed due to '
estr = '' if len(e.args) < 1 else (': ' + str(e))
warn(CacheMissingWarning(msg + e.__class__.__name__ + estr))
return False
with shelve.open(urlmapfn) as url2hash:
if url_key in url2hash:
return True
return False
def _do_download_files_in_parallel(args):
return download_file(*args)
def download_files_in_parallel(urls, cache=True, show_progress=True,
timeout=None):
"""
Downloads multiple files in parallel from the given URLs. Blocks until
all files have downloaded. The result is a list of local file paths
corresponding to the given urls.
Parameters
----------
urls : list of str
The URLs to retrieve.
cache : bool, optional
Whether to use the cache (default is `True`).
.. versionchanged:: 3.0
The default was changed to ``True`` and setting it to ``False`` will
print a Warning and set it to ``True`` again, because the function
will not work properly without cache.
show_progress : bool, optional
Whether to display a progress bar during the download (default
is `True`)
timeout : float, optional
Timeout for each individual requests in seconds (default is the
configurable `astropy.utils.data.Conf.remote_timeout`).
Returns
-------
paths : list of str
The local file paths corresponding to the downloaded URLs.
"""
from .console import ProgressBar
if timeout is None:
timeout = conf.remote_timeout
if not cache:
# See issue #6662, on windows won't work because the files are removed
# again before they can be used. On *NIX systems it will behave as if
# cache was set to True because multiprocessing cannot insert the items
# in the list of to-be-removed files.
warn("Disabling the cache does not work because of multiprocessing, it "
"will be set to ``True``. You may need to manually remove the "
"cached files afterwards.", AstropyWarning)
cache = True
if show_progress:
progress = sys.stdout
else:
progress = io.BytesIO()
# Combine duplicate URLs
combined_urls = list(set(urls))
combined_paths = ProgressBar.map(
_do_download_files_in_parallel,
[(x, cache, False, timeout) for x in combined_urls],
file=progress,
multiprocess=True)
paths = []
for url in urls:
paths.append(combined_paths[combined_urls.index(url)])
return paths
# This is used by download_file and _deltemps to determine the files to delete
# when the interpreter exits
_tempfilestodel = []
@atexit.register
def _deltemps():
global _tempfilestodel
if _tempfilestodel is not None:
while len(_tempfilestodel) > 0:
fn = _tempfilestodel.pop()
if os.path.isfile(fn):
os.remove(fn)
def clear_download_cache(hashorurl=None):
""" Clears the data file cache by deleting the local file(s).
Parameters
----------
hashorurl : str or None
If None, the whole cache is cleared. Otherwise, either specifies a
hash for the cached file that is supposed to be deleted, or a URL that
should be removed from the cache if present.
"""
try:
dldir, urlmapfn = _get_download_cache_locs()
except OSError as e:
msg = 'Not clearing data cache - cache inacessable due to '
estr = '' if len(e.args) < 1 else (': ' + str(e))
warn(CacheMissingWarning(msg + e.__class__.__name__ + estr))
return
_acquire_download_cache_lock()
try:
if hashorurl is None:
# dldir includes both the download files and the urlmapfn. This structure
# is required since we cannot know a priori the actual file name corresponding
# to the shelve map named urlmapfn.
if os.path.exists(dldir):
shutil.rmtree(dldir)
else:
with shelve.open(urlmapfn) as url2hash:
filepath = os.path.join(dldir, hashorurl)
if not _is_inside(filepath, dldir):
raise RuntimeError("attempted to use clear_download_cache on"
" a path outside the data cache directory")
hash_key = hashorurl
if os.path.exists(filepath):
for k, v in url2hash.items():
if v == filepath:
del url2hash[k]
os.unlink(filepath)
elif hash_key in url2hash:
filepath = url2hash[hash_key]
del url2hash[hash_key]
if os.path.exists(filepath):
# Make sure the filepath still actually exists (perhaps user removed it)
os.unlink(filepath)
# Otherwise could not find file or url, but no worries.
# Clearing download cache just makes sure that the file or url
# is no longer in the cache regardless of starting condition.
finally:
# the lock will be gone if rmtree was used above, but release otherwise
if os.path.exists(os.path.join(dldir, 'lock')):
_release_download_cache_lock()
def _get_download_cache_locs():
""" Finds the path to the data cache directory and makes them if
they don't exist.
Returns
-------
datadir : str
The path to the data cache directory.
shelveloc : str
The path to the shelve object that stores the cache info.
"""
from ..config.paths import get_cache_dir
# datadir includes both the download files and the shelveloc. This structure
# is required since we cannot know a priori the actual file name corresponding
# to the shelve map named shelveloc. (The backend can vary and is allowed to
# do whatever it wants with the filename. Filename munging can and does happen
# in practice).
py_version = 'py' + str(sys.version_info.major)
datadir = os.path.join(get_cache_dir(), 'download', py_version)
shelveloc = os.path.join(datadir, 'urlmap')
if not os.path.exists(datadir):
try:
os.makedirs(datadir)
except OSError as e:
if not os.path.exists(datadir):
raise
elif not os.path.isdir(datadir):
msg = 'Data cache directory {0} is not a directory'
raise OSError(msg.format(datadir))
if os.path.isdir(shelveloc):
msg = 'Data cache shelve object location {0} is a directory'
raise OSError(msg.format(shelveloc))
return datadir, shelveloc
# the cache directory must be locked before any writes are performed. Same for
# the hash shelve, so this should be used for both.
def _acquire_download_cache_lock():
"""
Uses the lock directory method. This is good because `mkdir` is
atomic at the system call level, so it's thread-safe.
"""
lockdir = os.path.join(_get_download_cache_locs()[0], 'lock')
for i in range(conf.download_cache_lock_attempts):
try:
os.mkdir(lockdir)
# write the pid of this process for informational purposes
with open(os.path.join(lockdir, 'pid'), 'w') as f:
f.write(str(os.getpid()))
except OSError:
time.sleep(1)
else:
return
msg = ("Unable to acquire lock for cache directory ({0} exists). "
"You may need to delete the lock if the python interpreter wasn't "
"shut down properly.")
raise RuntimeError(msg.format(lockdir))
def _release_download_cache_lock():
lockdir = os.path.join(_get_download_cache_locs()[0], 'lock')
if os.path.isdir(lockdir):
# if the pid file is present, be sure to remove it
pidfn = os.path.join(lockdir, 'pid')
if os.path.exists(pidfn):
os.remove(pidfn)
os.rmdir(lockdir)
else:
msg = 'Error releasing lock. "{0}" either does not exist or is not ' +\
'a directory.'
raise RuntimeError(msg.format(lockdir))
def get_cached_urls():
"""
Get the list of URLs in the cache. Especially useful for looking up what
files are stored in your cache when you don't have internet access.
Returns
-------
cached_urls : list
List of cached URLs.
"""
# The code below is modified from astropy.utils.data.download_file()
try:
dldir, urlmapfn = _get_download_cache_locs()
except OSError as e:
msg = 'Remote data cache could not be accessed due to '
estr = '' if len(e.args) < 1 else (': ' + str(e))
warn(CacheMissingWarning(msg + e.__class__.__name__ + estr))
return False
with shelve.open(urlmapfn) as url2hash:
return list(url2hash.keys())
|
8ae05a98090d689915915b9010180e2548d49361e3702d3a624e4868b2b2bbdb | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
A "grab bag" of relatively small general-purpose utilities that don't have
a clear module/package to live in.
"""
import abc
import contextlib
import difflib
import inspect
import json
import os
import signal
import sys
import traceback
import unicodedata
import locale
import threading
import re
import urllib.request
from itertools import zip_longest
from contextlib import contextmanager
from collections import defaultdict, OrderedDict
__all__ = ['isiterable', 'silence', 'format_exception', 'NumpyRNGContext',
'find_api_page', 'is_path_hidden', 'walk_skip_hidden',
'JsonCustomEncoder', 'indent', 'InheritDocstrings',
'OrderedDescriptor', 'OrderedDescriptorContainer', 'set_locale',
'ShapedLikeNDArray', 'check_broadcast', 'IncompatibleShapeError',
'dtype_bytes_or_chars']
def isiterable(obj):
"""Returns `True` if the given object is iterable."""
try:
iter(obj)
return True
except TypeError:
return False
def indent(s, shift=1, width=4):
"""Indent a block of text. The indentation is applied to each line."""
indented = '\n'.join(' ' * (width * shift) + l if l else ''
for l in s.splitlines())
if s[-1] == '\n':
indented += '\n'
return indented
class _DummyFile:
"""A noop writeable object."""
def write(self, s):
pass
@contextlib.contextmanager
def silence():
"""A context manager that silences sys.stdout and sys.stderr."""
old_stdout = sys.stdout
old_stderr = sys.stderr
sys.stdout = _DummyFile()
sys.stderr = _DummyFile()
yield
sys.stdout = old_stdout
sys.stderr = old_stderr
def format_exception(msg, *args, **kwargs):
"""
Given an exception message string, uses new-style formatting arguments
``{filename}``, ``{lineno}``, ``{func}`` and/or ``{text}`` to fill in
information about the exception that occurred. For example:
try:
1/0
except:
raise ZeroDivisionError(
format_except('A divide by zero occurred in {filename} at '
'line {lineno} of function {func}.'))
Any additional positional or keyword arguments passed to this function are
also used to format the message.
.. note::
This uses `sys.exc_info` to gather up the information needed to fill
in the formatting arguments. Since `sys.exc_info` is not carried
outside a handled exception, it's not wise to use this
outside of an ``except`` clause - if it is, this will substitute
'<unkown>' for the 4 formatting arguments.
"""
tb = traceback.extract_tb(sys.exc_info()[2], limit=1)
if len(tb) > 0:
filename, lineno, func, text = tb[0]
else:
filename = lineno = func = text = '<unknown>'
return msg.format(*args, filename=filename, lineno=lineno, func=func,
text=text, **kwargs)
class NumpyRNGContext:
"""
A context manager (for use with the ``with`` statement) that will seed the
numpy random number generator (RNG) to a specific value, and then restore
the RNG state back to whatever it was before.
This is primarily intended for use in the astropy testing suit, but it
may be useful in ensuring reproducibility of Monte Carlo simulations in a
science context.
Parameters
----------
seed : int
The value to use to seed the numpy RNG
Examples
--------
A typical use case might be::
with NumpyRNGContext(<some seed value you pick>):
from numpy import random
randarr = random.randn(100)
... run your test using `randarr` ...
#Any code using numpy.random at this indent level will act just as it
#would have if it had been before the with statement - e.g. whatever
#the default seed is.
"""
def __init__(self, seed):
self.seed = seed
def __enter__(self):
from numpy import random
self.startstate = random.get_state()
random.seed(self.seed)
def __exit__(self, exc_type, exc_value, traceback):
from numpy import random
random.set_state(self.startstate)
def find_api_page(obj, version=None, openinbrowser=True, timeout=None):
"""
Determines the URL of the API page for the specified object, and
optionally open that page in a web browser.
.. note::
You must be connected to the internet for this to function even if
``openinbrowser`` is `False`, unless you provide a local version of
the documentation to ``version`` (e.g., ``file:///path/to/docs``).
Parameters
----------
obj
The object to open the docs for or its fully-qualified name
(as a str).
version : str
The doc version - either a version number like '0.1', 'dev' for
the development/latest docs, or a URL to point to a specific
location that should be the *base* of the documentation. Defaults to
latest if you are on aren't on a release, otherwise, the version you
are on.
openinbrowser : bool
If `True`, the `webbrowser` package will be used to open the doc
page in a new web browser window.
timeout : number, optional
The number of seconds to wait before timing-out the query to
the astropy documentation. If not given, the default python
stdlib timeout will be used.
Returns
-------
url : str
The loaded URL
Raises
------
ValueError
If the documentation can't be found
"""
import webbrowser
from zlib import decompress
if (not isinstance(obj, str) and
hasattr(obj, '__module__') and
hasattr(obj, '__name__')):
obj = obj.__module__ + '.' + obj.__name__
elif inspect.ismodule(obj):
obj = obj.__name__
if version is None:
from .. import version
if version.release:
version = 'v' + version.version
else:
version = 'dev'
if '://' in version:
if version.endswith('index.html'):
baseurl = version[:-10]
elif version.endswith('/'):
baseurl = version
else:
baseurl = version + '/'
elif version == 'dev' or version == 'latest':
baseurl = 'http://devdocs.astropy.org/'
else:
baseurl = 'http://docs.astropy.org/en/{vers}/'.format(vers=version)
if timeout is None:
uf = urllib.request.urlopen(baseurl + 'objects.inv')
else:
uf = urllib.request.urlopen(baseurl + 'objects.inv', timeout=timeout)
try:
oiread = uf.read()
# need to first read/remove the first four lines, which have info before
# the compressed section with the actual object inventory
idx = -1
headerlines = []
for _ in range(4):
oldidx = idx
idx = oiread.index(b'\n', oldidx + 1)
headerlines.append(oiread[(oldidx+1):idx].decode('utf-8'))
# intersphinx version line, project name, and project version
ivers, proj, vers, compr = headerlines
if 'The remainder of this file is compressed using zlib' not in compr:
raise ValueError('The file downloaded from {0} does not seem to be'
'the usual Sphinx objects.inv format. Maybe it '
'has changed?'.format(baseurl + 'objects.inv'))
compressed = oiread[(idx+1):]
finally:
uf.close()
decompressed = decompress(compressed).decode('utf-8')
resurl = None
for l in decompressed.strip().splitlines():
ls = l.split()
name = ls[0]
loc = ls[3]
if loc.endswith('$'):
loc = loc[:-1] + name
if name == obj:
resurl = baseurl + loc
break
if resurl is None:
raise ValueError('Could not find the docs for the object {obj}'.format(obj=obj))
elif openinbrowser:
webbrowser.open(resurl)
return resurl
def signal_number_to_name(signum):
"""
Given an OS signal number, returns a signal name. If the signal
number is unknown, returns ``'UNKNOWN'``.
"""
# Since these numbers and names are platform specific, we use the
# builtin signal module and build a reverse mapping.
signal_to_name_map = dict((k, v) for v, k in signal.__dict__.items()
if v.startswith('SIG'))
return signal_to_name_map.get(signum, 'UNKNOWN')
if sys.platform == 'win32':
import ctypes
def _has_hidden_attribute(filepath):
"""
Returns True if the given filepath has the hidden attribute on
MS-Windows. Based on a post here:
http://stackoverflow.com/questions/284115/cross-platform-hidden-file-detection
"""
if isinstance(filepath, bytes):
filepath = filepath.decode(sys.getfilesystemencoding())
try:
attrs = ctypes.windll.kernel32.GetFileAttributesW(filepath)
result = bool(attrs & 2) and attrs != -1
except AttributeError:
result = False
return result
else:
def _has_hidden_attribute(filepath):
return False
def is_path_hidden(filepath):
"""
Determines if a given file or directory is hidden.
Parameters
----------
filepath : str
The path to a file or directory
Returns
-------
hidden : bool
Returns `True` if the file is hidden
"""
name = os.path.basename(os.path.abspath(filepath))
if isinstance(name, bytes):
is_dotted = name.startswith(b'.')
else:
is_dotted = name.startswith('.')
return is_dotted or _has_hidden_attribute(filepath)
def walk_skip_hidden(top, onerror=None, followlinks=False):
"""
A wrapper for `os.walk` that skips hidden files and directories.
This function does not have the parameter ``topdown`` from
`os.walk`: the directories must always be recursed top-down when
using this function.
See also
--------
os.walk : For a description of the parameters
"""
for root, dirs, files in os.walk(
top, topdown=True, onerror=onerror,
followlinks=followlinks):
# These lists must be updated in-place so os.walk will skip
# hidden directories
dirs[:] = [d for d in dirs if not is_path_hidden(d)]
files[:] = [f for f in files if not is_path_hidden(f)]
yield root, dirs, files
class JsonCustomEncoder(json.JSONEncoder):
"""Support for data types that JSON default encoder
does not do.
This includes:
* Numpy array or number
* Complex number
* Set
* Bytes
* astropy.UnitBase
* astropy.Quantity
Examples
--------
>>> import json
>>> import numpy as np
>>> from astropy.utils.misc import JsonCustomEncoder
>>> json.dumps(np.arange(3), cls=JsonCustomEncoder)
'[0, 1, 2]'
"""
def default(self, obj):
from .. import units as u
import numpy as np
if isinstance(obj, u.Quantity):
return dict(value=obj.value, unit=obj.unit.to_string())
if isinstance(obj, (np.number, np.ndarray)):
return obj.tolist()
elif isinstance(obj, complex):
return [obj.real, obj.imag]
elif isinstance(obj, set):
return list(obj)
elif isinstance(obj, bytes): # pragma: py3
return obj.decode()
elif isinstance(obj, (u.UnitBase, u.FunctionUnitBase)):
if obj == u.dimensionless_unscaled:
obj = 'dimensionless_unit'
else:
return obj.to_string()
return json.JSONEncoder.default(self, obj)
def strip_accents(s):
"""
Remove accents from a Unicode string.
This helps with matching "ångström" to "angstrom", for example.
"""
return ''.join(
c for c in unicodedata.normalize('NFD', s)
if unicodedata.category(c) != 'Mn')
def did_you_mean(s, candidates, n=3, cutoff=0.8, fix=None):
"""
When a string isn't found in a set of candidates, we can be nice
to provide a list of alternatives in the exception. This
convenience function helps to format that part of the exception.
Parameters
----------
s : str
candidates : sequence of str or dict of str keys
n : int
The maximum number of results to include. See
`difflib.get_close_matches`.
cutoff : float
In the range [0, 1]. Possibilities that don't score at least
that similar to word are ignored. See
`difflib.get_close_matches`.
fix : callable
A callable to modify the results after matching. It should
take a single string and return a sequence of strings
containing the fixed matches.
Returns
-------
message : str
Returns the string "Did you mean X, Y, or Z?", or the empty
string if no alternatives were found.
"""
if isinstance(s, str):
s = strip_accents(s)
s_lower = s.lower()
# Create a mapping from the lower case name to all capitalization
# variants of that name.
candidates_lower = {}
for candidate in candidates:
candidate_lower = candidate.lower()
candidates_lower.setdefault(candidate_lower, [])
candidates_lower[candidate_lower].append(candidate)
# The heuristic here is to first try "singularizing" the word. If
# that doesn't match anything use difflib to find close matches in
# original, lower and upper case.
if s_lower.endswith('s') and s_lower[:-1] in candidates_lower:
matches = [s_lower[:-1]]
else:
matches = difflib.get_close_matches(
s_lower, candidates_lower, n=n, cutoff=cutoff)
if len(matches):
capitalized_matches = set()
for match in matches:
capitalized_matches.update(candidates_lower[match])
matches = capitalized_matches
if fix is not None:
mapped_matches = []
for match in matches:
mapped_matches.extend(fix(match))
matches = mapped_matches
matches = list(set(matches))
matches = sorted(matches)
if len(matches) == 1:
matches = matches[0]
else:
matches = (', '.join(matches[:-1]) + ' or ' +
matches[-1])
return 'Did you mean {0}?'.format(matches)
return ''
class InheritDocstrings(type):
"""
This metaclass makes methods of a class automatically have their
docstrings filled in from the methods they override in the base
class.
If the class uses multiple inheritance, the docstring will be
chosen from the first class in the bases list, in the same way as
methods are normally resolved in Python. If this results in
selecting the wrong docstring, the docstring will need to be
explicitly included on the method.
For example::
>>> from astropy.utils.misc import InheritDocstrings
>>> class A(metaclass=InheritDocstrings):
... def wiggle(self):
... "Wiggle the thingamajig"
... pass
>>> class B(A):
... def wiggle(self):
... pass
>>> B.wiggle.__doc__
u'Wiggle the thingamajig'
"""
def __init__(cls, name, bases, dct):
def is_public_member(key):
return (
(key.startswith('__') and key.endswith('__')
and len(key) > 4) or
not key.startswith('_'))
for key, val in dct.items():
if (inspect.isfunction(val) and
is_public_member(key) and
val.__doc__ is None):
for base in cls.__mro__[1:]:
super_method = getattr(base, key, None)
if super_method is not None:
val.__doc__ = super_method.__doc__
break
super().__init__(name, bases, dct)
class OrderedDescriptor(metaclass=abc.ABCMeta):
"""
Base class for descriptors whose order in the class body should be
preserved. Intended for use in concert with the
`OrderedDescriptorContainer` metaclass.
Subclasses of `OrderedDescriptor` must define a value for a class attribute
called ``_class_attribute_``. This is the name of a class attribute on the
*container* class for these descriptors, which will be set to an
`~collections.OrderedDict` at class creation time. This
`~collections.OrderedDict` will contain a mapping of all class attributes
that were assigned instances of the `OrderedDescriptor` subclass, to the
instances themselves. See the documentation for
`OrderedDescriptorContainer` for a concrete example.
Optionally, subclasses of `OrderedDescriptor` may define a value for a
class attribute called ``_name_attribute_``. This should be the name of
an attribute on instances of the subclass. When specified, during
creation of a class containing these descriptors, the name attribute on
each instance will be set to the name of the class attribute it was
assigned to on the class.
.. note::
Although this class is intended for use with *descriptors* (i.e.
classes that define any of the ``__get__``, ``__set__``, or
``__delete__`` magic methods), this base class is not itself a
descriptor, and technically this could be used for classes that are
not descriptors too. However, use with descriptors is the original
intended purpose.
"""
# This id increments for each OrderedDescriptor instance created, so they
# are always ordered in the order they were created. Class bodies are
# guaranteed to be executed from top to bottom. Not sure if this is
# thread-safe though.
_nextid = 1
@property
@abc.abstractmethod
def _class_attribute_(self):
"""
Subclasses should define this attribute to the name of an attribute on
classes containing this subclass. That attribute will contain the mapping
of all instances of that `OrderedDescriptor` subclass defined in the class
body. If the same descriptor needs to be used with different classes,
each with different names of this attribute, multiple subclasses will be
needed.
"""
_name_attribute_ = None
"""
Subclasses may optionally define this attribute to specify the name of an
attribute on instances of the class that should be filled with the
instance's attribute name at class creation time.
"""
def __init__(self, *args, **kwargs):
# The _nextid attribute is shared across all subclasses so that
# different subclasses of OrderedDescriptors can be sorted correctly
# between themselves
self.__order = OrderedDescriptor._nextid
OrderedDescriptor._nextid += 1
super().__init__()
def __lt__(self, other):
"""
Defined for convenient sorting of `OrderedDescriptor` instances, which
are defined to sort in their creation order.
"""
if (isinstance(self, OrderedDescriptor) and
isinstance(other, OrderedDescriptor)):
try:
return self.__order < other.__order
except AttributeError:
raise RuntimeError(
'Could not determine ordering for {0} and {1}; at least '
'one of them is not calling super().__init__ in its '
'__init__.'.format(self, other))
else:
return NotImplemented
class OrderedDescriptorContainer(type):
"""
Classes should use this metaclass if they wish to use `OrderedDescriptor`
attributes, which are class attributes that "remember" the order in which
they were defined in the class body.
Every subclass of `OrderedDescriptor` has an attribute called
``_class_attribute_``. For example, if we have
.. code:: python
class ExampleDecorator(OrderedDescriptor):
_class_attribute_ = '_examples_'
Then when a class with the `OrderedDescriptorContainer` metaclass is
created, it will automatically be assigned a class attribute ``_examples_``
referencing an `~collections.OrderedDict` containing all instances of
``ExampleDecorator`` defined in the class body, mapped to by the names of
the attributes they were assigned to.
When subclassing a class with this metaclass, the descriptor dict (i.e.
``_examples_`` in the above example) will *not* contain descriptors
inherited from the base class. That is, this only works by default with
decorators explicitly defined in the class body. However, the subclass
*may* define an attribute ``_inherit_decorators_`` which lists
`OrderedDescriptor` classes that *should* be added from base classes.
See the examples section below for an example of this.
Examples
--------
>>> from astropy.utils import OrderedDescriptor, OrderedDescriptorContainer
>>> class TypedAttribute(OrderedDescriptor):
... \"\"\"
... Attributes that may only be assigned objects of a specific type,
... or subclasses thereof. For some reason we care about their order.
... \"\"\"
...
... _class_attribute_ = 'typed_attributes'
... _name_attribute_ = 'name'
... # A default name so that instances not attached to a class can
... # still be repr'd; useful for debugging
... name = '<unbound>'
...
... def __init__(self, type):
... # Make sure not to forget to call the super __init__
... super().__init__()
... self.type = type
...
... def __get__(self, obj, objtype=None):
... if obj is None:
... return self
... if self.name in obj.__dict__:
... return obj.__dict__[self.name]
... else:
... raise AttributeError(self.name)
...
... def __set__(self, obj, value):
... if not isinstance(value, self.type):
... raise ValueError('{0}.{1} must be of type {2!r}'.format(
... obj.__class__.__name__, self.name, self.type))
... obj.__dict__[self.name] = value
...
... def __delete__(self, obj):
... if self.name in obj.__dict__:
... del obj.__dict__[self.name]
... else:
... raise AttributeError(self.name)
...
... def __repr__(self):
... if isinstance(self.type, tuple) and len(self.type) > 1:
... typestr = '({0})'.format(
... ', '.join(t.__name__ for t in self.type))
... else:
... typestr = self.type.__name__
... return '<{0}(name={1}, type={2})>'.format(
... self.__class__.__name__, self.name, typestr)
...
Now let's create an example class that uses this ``TypedAttribute``::
>>> class Point2D(metaclass=OrderedDescriptorContainer):
... x = TypedAttribute((float, int))
... y = TypedAttribute((float, int))
...
... def __init__(self, x, y):
... self.x, self.y = x, y
...
>>> p1 = Point2D(1.0, 2.0)
>>> p1.x
1.0
>>> p1.y
2.0
>>> p2 = Point2D('a', 'b') # doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
...
ValueError: Point2D.x must be of type (float, int>)
We see that ``TypedAttribute`` works more or less as advertised, but
there's nothing special about that. Let's see what
`OrderedDescriptorContainer` did for us::
>>> Point2D.typed_attributes
OrderedDict([('x', <TypedAttribute(name=x, type=(float, int))>),
('y', <TypedAttribute(name=y, type=(float, int))>)])
If we create a subclass, it does *not* by default add inherited descriptors
to ``typed_attributes``::
>>> class Point3D(Point2D):
... z = TypedAttribute((float, int))
...
>>> Point3D.typed_attributes
OrderedDict([('z', <TypedAttribute(name=z, type=(float, int))>)])
However, if we specify ``_inherit_descriptors_`` from ``Point2D`` then
it will do so::
>>> class Point3D(Point2D):
... _inherit_descriptors_ = (TypedAttribute,)
... z = TypedAttribute((float, int))
...
>>> Point3D.typed_attributes
OrderedDict([('x', <TypedAttribute(name=x, type=(float, int))>),
('y', <TypedAttribute(name=y, type=(float, int))>),
('z', <TypedAttribute(name=z, type=(float, int))>)])
.. note::
Hopefully it is clear from these examples that this construction
also allows a class of type `OrderedDescriptorContainer` to use
multiple different `OrderedDescriptor` classes simultaneously.
"""
_inherit_descriptors_ = ()
def __init__(cls, cls_name, bases, members):
descriptors = defaultdict(list)
seen = set()
inherit_descriptors = ()
descr_bases = {}
for mro_cls in cls.__mro__:
for name, obj in mro_cls.__dict__.items():
if name in seen:
# Checks if we've already seen an attribute of the given
# name (if so it will override anything of the same name in
# any base class)
continue
seen.add(name)
if (not isinstance(obj, OrderedDescriptor) or
(inherit_descriptors and
not isinstance(obj, inherit_descriptors))):
# The second condition applies when checking any
# subclasses, to see if we can inherit any descriptors of
# the given type from subclasses (by default inheritance is
# disabled unless the class has _inherit_descriptors_
# defined)
continue
if obj._name_attribute_ is not None:
setattr(obj, obj._name_attribute_, name)
# Don't just use the descriptor's class directly; instead go
# through its MRO and find the class on which _class_attribute_
# is defined directly. This way subclasses of some
# OrderedDescriptor *may* override _class_attribute_ and have
# its own _class_attribute_, but by default all subclasses of
# some OrderedDescriptor are still grouped together
# TODO: It might be worth clarifying this in the docs
if obj.__class__ not in descr_bases:
for obj_cls_base in obj.__class__.__mro__:
if '_class_attribute_' in obj_cls_base.__dict__:
descr_bases[obj.__class__] = obj_cls_base
descriptors[obj_cls_base].append((obj, name))
break
else:
# Make sure to put obj first for sorting purposes
obj_cls_base = descr_bases[obj.__class__]
descriptors[obj_cls_base].append((obj, name))
if not getattr(mro_cls, '_inherit_descriptors_', False):
# If _inherit_descriptors_ is undefined then we don't inherit
# any OrderedDescriptors from any of the base classes, and
# there's no reason to continue through the MRO
break
else:
inherit_descriptors = mro_cls._inherit_descriptors_
for descriptor_cls, instances in descriptors.items():
instances.sort()
instances = OrderedDict((key, value) for value, key in instances)
setattr(cls, descriptor_cls._class_attribute_, instances)
super().__init__(cls_name, bases, members)
LOCALE_LOCK = threading.Lock()
@contextmanager
def set_locale(name):
"""
Context manager to temporarily set the locale to ``name``.
An example is setting locale to "C" so that the C strtod()
function will use "." as the decimal point to enable consistent
numerical string parsing.
Note that one cannot nest multiple set_locale() context manager
statements as this causes a threading lock.
This code taken from https://stackoverflow.com/questions/18593661/how-do-i-strftime-a-date-object-in-a-different-locale.
Parameters
==========
name : str
Locale name, e.g. "C" or "fr_FR".
"""
name = str(name)
with LOCALE_LOCK:
saved = locale.setlocale(locale.LC_ALL)
if saved == name:
# Don't do anything if locale is already the requested locale
yield
else:
try:
locale.setlocale(locale.LC_ALL, name)
yield
finally:
locale.setlocale(locale.LC_ALL, saved)
class ShapedLikeNDArray(metaclass=abc.ABCMeta):
"""Mixin class to provide shape-changing methods.
The class proper is assumed to have some underlying data, which are arrays
or array-like structures. It must define a ``shape`` property, which gives
the shape of those data, as well as an ``_apply`` method that creates a new
instance in which a `~numpy.ndarray` method has been applied to those.
Furthermore, for consistency with `~numpy.ndarray`, it is recommended to
define a setter for the ``shape`` property, which, like the
`~numpy.ndarray.shape` property allows in-place reshaping the internal data
(and, unlike the ``reshape`` method raises an exception if this is not
possible).
This class also defines default implementations for ``ndim`` and ``size``
properties, calculating those from the ``shape``. These can be overridden
by subclasses if there are faster ways to obtain those numbers.
"""
# Note to developers: if new methods are added here, be sure to check that
# they work properly with the classes that use this, such as Time and
# BaseRepresentation, i.e., look at their ``_apply`` methods and add
# relevant tests. This is particularly important for methods that imply
# copies rather than views of data (see the special-case treatment of
# 'flatten' in Time).
@property
@abc.abstractmethod
def shape(self):
"""The shape of the instance and underlying arrays."""
@abc.abstractmethod
def _apply(method, *args, **kwargs):
"""Create a new instance, with ``method`` applied to underlying data.
The method is any of the shape-changing methods for `~numpy.ndarray`
(``reshape``, ``swapaxes``, etc.), as well as those picking particular
elements (``__getitem__``, ``take``, etc.). It will be applied to the
underlying arrays (e.g., ``jd1`` and ``jd2`` in `~astropy.time.Time`),
with the results used to create a new instance.
Parameters
----------
method : str
Method to be applied to the instance's internal data arrays.
args : tuple
Any positional arguments for ``method``.
kwargs : dict
Any keyword arguments for ``method``.
"""
@property
def ndim(self):
"""The number of dimensions of the instance and underlying arrays."""
return len(self.shape)
@property
def size(self):
"""The size of the object, as calculated from its shape."""
size = 1
for sh in self.shape:
size *= sh
return size
@property
def isscalar(self):
return self.shape == ()
def __len__(self):
if self.isscalar:
raise TypeError("Scalar {0!r} object has no len()"
.format(self.__class__.__name__))
return self.shape[0]
def __bool__(self):
"""Any instance should evaluate to True, except when it is empty."""
return self.size > 0
def __getitem__(self, item):
try:
return self._apply('__getitem__', item)
except IndexError:
if self.isscalar:
raise TypeError('scalar {0!r} object is not subscriptable.'
.format(self.__class__.__name__))
else:
raise
def __iter__(self):
if self.isscalar:
raise TypeError('scalar {0!r} object is not iterable.'
.format(self.__class__.__name__))
# We cannot just write a generator here, since then the above error
# would only be raised once we try to use the iterator, rather than
# upon its definition using iter(self).
def self_iter():
for idx in range(len(self)):
yield self[idx]
return self_iter()
def copy(self, *args, **kwargs):
"""Return an instance containing copies of the internal data.
Parameters are as for :meth:`~numpy.ndarray.copy`.
"""
return self._apply('copy', *args, **kwargs)
def reshape(self, *args, **kwargs):
"""Returns an instance containing the same data with a new shape.
Parameters are as for :meth:`~numpy.ndarray.reshape`. Note that it is
not always possible to change the shape of an array without copying the
data (see :func:`~numpy.reshape` documentation). If you want an error
to be raise if the data is copied, you should assign the new shape to
the shape attribute (note: this may not be implemented for all classes
using ``ShapedLikeNDArray``).
"""
return self._apply('reshape', *args, **kwargs)
def ravel(self, *args, **kwargs):
"""Return an instance with the array collapsed into one dimension.
Parameters are as for :meth:`~numpy.ndarray.ravel`. Note that it is
not always possible to unravel an array without copying the data.
If you want an error to be raise if the data is copied, you should
should assign shape ``(-1,)`` to the shape attribute.
"""
return self._apply('ravel', *args, **kwargs)
def flatten(self, *args, **kwargs):
"""Return a copy with the array collapsed into one dimension.
Parameters are as for :meth:`~numpy.ndarray.flatten`.
"""
return self._apply('flatten', *args, **kwargs)
def transpose(self, *args, **kwargs):
"""Return an instance with the data transposed.
Parameters are as for :meth:`~numpy.ndarray.transpose`. All internal
data are views of the data of the original.
"""
return self._apply('transpose', *args, **kwargs)
@property
def T(self):
"""Return an instance with the data transposed.
Parameters are as for :attr:`~numpy.ndarray.T`. All internal
data are views of the data of the original.
"""
if self.ndim < 2:
return self
else:
return self.transpose()
def swapaxes(self, *args, **kwargs):
"""Return an instance with the given axes interchanged.
Parameters are as for :meth:`~numpy.ndarray.swapaxes`:
``axis1, axis2``. All internal data are views of the data of the
original.
"""
return self._apply('swapaxes', *args, **kwargs)
def diagonal(self, *args, **kwargs):
"""Return an instance with the specified diagonals.
Parameters are as for :meth:`~numpy.ndarray.diagonal`. All internal
data are views of the data of the original.
"""
return self._apply('diagonal', *args, **kwargs)
def squeeze(self, *args, **kwargs):
"""Return an instance with single-dimensional shape entries removed
Parameters are as for :meth:`~numpy.ndarray.squeeze`. All internal
data are views of the data of the original.
"""
return self._apply('squeeze', *args, **kwargs)
def take(self, indices, axis=None, mode='raise'):
"""Return a new instance formed from the elements at the given indices.
Parameters are as for :meth:`~numpy.ndarray.take`, except that,
obviously, no output array can be given.
"""
return self._apply('take', indices, axis=axis, mode=mode)
class IncompatibleShapeError(ValueError):
def __init__(self, shape_a, shape_a_idx, shape_b, shape_b_idx):
super().__init__(shape_a, shape_a_idx, shape_b, shape_b_idx)
def check_broadcast(*shapes):
"""
Determines whether two or more Numpy arrays can be broadcast with each
other based on their shape tuple alone.
Parameters
----------
*shapes : tuple
All shapes to include in the comparison. If only one shape is given it
is passed through unmodified. If no shapes are given returns an empty
`tuple`.
Returns
-------
broadcast : `tuple`
If all shapes are mutually broadcastable, returns a tuple of the full
broadcast shape.
"""
if len(shapes) == 0:
return ()
elif len(shapes) == 1:
return shapes[0]
reversed_shapes = (reversed(shape) for shape in shapes)
full_shape = []
for dims in zip_longest(*reversed_shapes, fillvalue=1):
max_dim = 1
max_dim_idx = None
for idx, dim in enumerate(dims):
if dim == 1:
continue
if max_dim == 1:
# The first dimension of size greater than 1
max_dim = dim
max_dim_idx = idx
elif dim != max_dim:
raise IncompatibleShapeError(
shapes[max_dim_idx], max_dim_idx, shapes[idx], idx)
full_shape.append(max_dim)
return tuple(full_shape[::-1])
def dtype_bytes_or_chars(dtype):
"""
Parse the number out of a dtype.str value like '<U5' or '<f8'.
See #5819 for discussion on the need for this function for getting
the number of characters corresponding to a string dtype.
Parameters
----------
dtype : numpy dtype object
Input dtype
Returns
-------
bytes_or_chars : int or None
Bits (for numeric types) or characters (for string types)
"""
match = re.search(r'(\d+)$', dtype.str)
out = int(match.group(1)) if match else None
return out
|
f88a53718225b85da742cac0b2115fc65cf2a2ccea081d86b5448319c49002a4 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Handle loading six package from system or from the bundled copy
"""
import imp
from distutils.version import StrictVersion
_SIX_MIN_VERSION = StrictVersion('1.10.0')
# Update this to prevent Astropy from using its bundled copy of six
# (but only if some other version of at least _SIX_MIN_VERSION can
# be provided)
_SIX_SEARCH_PATH = ['astropy.extern.bundled.six', 'six']
def _find_module(name, path=None):
"""
Alternative to `imp.find_module` that can also search in subpackages.
"""
parts = name.split('.')
for part in parts:
if path is not None:
path = [path]
fh, path, descr = imp.find_module(part, path)
return fh, path, descr
def _import_six(search_path=_SIX_SEARCH_PATH):
for mod_name in search_path:
try:
mod_info = _find_module(mod_name)
except ImportError:
continue
mod = imp.load_module(__name__, *mod_info)
try:
if StrictVersion(mod.__version__) >= _SIX_MIN_VERSION:
break
except (AttributeError, ValueError):
# Attribute error if the six module isn't what it should be and
# doesn't have a .__version__; ValueError if the version string
# exists but is somehow bogus/unparseable
continue
else:
raise ImportError(
"Astropy requires the 'six' module of minimum version {0}; "
"normally this is bundled with the astropy package so if you get "
"this warning consult the packager of your Astropy "
"distribution.".format(_SIX_MIN_VERSION))
_import_six()
|
a0ebf94694e1b9041eb99b9eb9cb66cfd954947d06cd53e9b3c1509358a0a6aa | # Licensed under a 3-clause BSD style license - see LICENSE.rst
import os
def get_package_data():
paths = [os.path.join('js', '*.js'), os.path.join('css', '*.css')]
return {'astropy.extern': paths}
|
131ce5a64bb9fae13ab946e090a9d9b9c4e10438846254db93928fd9b067773e | """
Normalization class for Matplotlib that can be used to produce
colorbars.
"""
import numpy as np
from numpy import ma
from .interval import (PercentileInterval, AsymmetricPercentileInterval,
ManualInterval, MinMaxInterval, BaseInterval)
from .stretch import (LinearStretch, SqrtStretch, PowerStretch, LogStretch,
AsinhStretch, BaseStretch)
try:
import matplotlib # pylint: disable=W0611
from matplotlib.colors import Normalize
except ImportError:
class Normalize:
def __init__(self, *args, **kwargs):
raise ImportError('matplotlib is required in order to use this '
'class.')
__all__ = ['ImageNormalize', 'simple_norm']
__doctest_requires__ = {'*': ['matplotlib']}
class ImageNormalize(Normalize):
"""
Normalization class to be used with Matplotlib.
Parameters
----------
data : `~numpy.ndarray`, optional
The image array. This input is used only if ``interval`` is
also input. ``data`` and ``interval`` are used to compute the
vmin and/or vmax values only if ``vmin`` or ``vmax`` are not
input.
interval : `~astropy.visualization.BaseInterval` subclass instance, optional
The interval object to apply to the input ``data`` to determine
the ``vmin`` and ``vmax`` values. This input is used only if
``data`` is also input. ``data`` and ``interval`` are used to
compute the vmin and/or vmax values only if ``vmin`` or ``vmax``
are not input.
vmin, vmax : float
The minimum and maximum levels to show for the data. The
``vmin`` and ``vmax`` inputs override any calculated values from
the ``interval`` and ``data`` inputs.
stretch : `~astropy.visualization.BaseStretch` subclass instance, optional
The stretch object to apply to the data. The default is
`~astropy.visualization.LinearStretch`.
clip : bool, optional
If `True` (default), data values outside the [0:1] range are
clipped to the [0:1] range.
"""
def __init__(self, data=None, interval=None, vmin=None, vmax=None,
stretch=LinearStretch(), clip=False):
# this super call checks for matplotlib
super().__init__(vmin=vmin, vmax=vmax, clip=clip)
self.vmin = vmin
self.vmax = vmax
if data is not None and interval is not None:
_vmin, _vmax = interval.get_limits(data)
if self.vmin is None:
self.vmin = _vmin
if self.vmax is None:
self.vmax = _vmax
if stretch is not None and not isinstance(stretch, BaseStretch):
raise TypeError('stretch must be an instance of a BaseStretch '
'subclass')
self.stretch = stretch
if interval is not None and not isinstance(interval, BaseInterval):
raise TypeError('interval must be an instance of a BaseInterval '
'subclass')
self.interval = interval
self.inverse_stretch = stretch.inverse
self.clip = clip
def __call__(self, values, clip=None):
if clip is None:
clip = self.clip
if isinstance(values, ma.MaskedArray):
if clip:
mask = False
else:
mask = values.mask
values = values.filled(self.vmax)
else:
mask = False
# Make sure scalars get broadcast to 1-d
if np.isscalar(values):
values = np.array([values], dtype=float)
else:
# copy because of in-place operations after
values = np.array(values, copy=True, dtype=float)
# Set default values for vmin and vmax if not specified
self.autoscale_None(values)
# Normalize based on vmin and vmax
np.subtract(values, self.vmin, out=values)
np.true_divide(values, self.vmax - self.vmin, out=values)
# Clip to the 0 to 1 range
if self.clip:
values = np.clip(values, 0., 1., out=values)
# Stretch values
values = self.stretch(values, out=values, clip=False)
# Convert to masked array for matplotlib
return ma.array(values, mask=mask)
def inverse(self, values):
# Find unstretched values in range 0 to 1
values_norm = self.inverse_stretch(values, clip=False)
# Scale to original range
return values_norm * (self.vmax - self.vmin) + self.vmin
def simple_norm(data, stretch='linear', power=1.0, asinh_a=0.1, min_cut=None,
max_cut=None, min_percent=None, max_percent=None,
percent=None, clip=True):
"""
Return a Normalization class that can be used for displaying images
with Matplotlib.
This function enables only a subset of image stretching functions
available in `~astropy.visualization.mpl_normalize.ImageNormalize`.
This function is used by the
``astropy.visualization.scripts.fits2bitmap`` script.
Parameters
----------
data : `~numpy.ndarray`
The image array.
stretch : {'linear', 'sqrt', 'power', log', 'asinh'}, optional
The stretch function to apply to the image. The default is
'linear'.
power : float, optional
The power index for ``stretch='power'``. The default is 1.0.
asinh_a : float, optional
For ``stretch='asinh'``, the value where the asinh curve
transitions from linear to logarithmic behavior, expressed as a
fraction of the normalized image. Must be in the range between
0 and 1. The default is 0.1.
min_cut : float, optional
The pixel value of the minimum cut level. Data values less than
``min_cut`` will set to ``min_cut`` before stretching the image.
The default is the image minimum. ``min_cut`` overrides
``min_percent``.
max_cut : float, optional
The pixel value of the maximum cut level. Data values greater
than ``min_cut`` will set to ``min_cut`` before stretching the
image. The default is the image maximum. ``max_cut`` overrides
``max_percent``.
min_percent : float, optional
The percentile value used to determine the pixel value of
minimum cut level. The default is 0.0. ``min_percent``
overrides ``percent``.
max_percent : float, optional
The percentile value used to determine the pixel value of
maximum cut level. The default is 100.0. ``max_percent``
overrides ``percent``.
percent : float, optional
The percentage of the image values used to determine the pixel
values of the minimum and maximum cut levels. The lower cut
level will set at the ``(100 - percent) / 2`` percentile, while
the upper cut level will be set at the ``(100 + percent) / 2``
percentile. The default is 100.0. ``percent`` is ignored if
either ``min_percent`` or ``max_percent`` is input.
clip : bool, optional
If `True` (default), data values outside the [0:1] range are
clipped to the [0:1] range.
Returns
-------
result : `ImageNormalize` instance
An `ImageNormalize` instance that can be used for displaying
images with Matplotlib.
"""
if percent is not None:
interval = PercentileInterval(percent)
elif min_percent is not None or max_percent is not None:
interval = AsymmetricPercentileInterval(min_percent or 0.,
max_percent or 100.)
elif min_cut is not None or max_cut is not None:
interval = ManualInterval(min_cut, max_cut)
else:
interval = MinMaxInterval()
if stretch == 'linear':
stretch = LinearStretch()
elif stretch == 'sqrt':
stretch = SqrtStretch()
elif stretch == 'power':
stretch = PowerStretch(power)
elif stretch == 'log':
stretch = LogStretch()
elif stretch == 'asinh':
stretch = AsinhStretch(asinh_a)
else:
raise ValueError('Unknown stretch: {0}.'.format(stretch))
vmin, vmax = interval.get_limits(data)
return ImageNormalize(vmin=vmin, vmax=vmax, stretch=stretch, clip=clip)
|
13d205d55822cdff646031abb07281cc01d9a97c2ad890fa7088030a9fe036c3 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
from .hist import *
from .interval import *
from .mpl_normalize import *
from .mpl_style import *
from .stretch import *
from .transform import *
from .units import *
from .lupton_rgb import *
|
05ff8868d3e60549bd538d29de9611d6a96f21e19fd3752a48ba91336424eda9 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Combine 3 images to produce a properly-scaled RGB image following Lupton et al. (2004).
The three images must be aligned and have the same pixel scale and size.
For details, see : http://adsabs.harvard.edu/abs/2004PASP..116..133L
"""
import numpy as np
from . import ZScaleInterval
__all__ = ['make_lupton_rgb']
def compute_intensity(image_r, image_g=None, image_b=None):
"""
Return a naive total intensity from the red, blue, and green intensities.
Parameters
----------
image_r : `~numpy.ndarray`
Intensity of image to be mapped to red; or total intensity if ``image_g``
and ``image_b`` are None.
image_g : `~numpy.ndarray`, optional
Intensity of image to be mapped to green.
image_b : `~numpy.ndarray`, optional
Intensity of image to be mapped to blue.
Returns
-------
intensity : `~numpy.ndarray`
Total intensity from the red, blue and green intensities, or ``image_r``
if green and blue images are not provided.
"""
if image_g is None or image_b is None:
if not (image_g is None and image_b is None):
raise ValueError("please specify either a single image "
"or red, green, and blue images.")
return image_r
intensity = (image_r + image_g + image_b)/3.0
# Repack into whatever type was passed to us
return np.asarray(intensity, dtype=image_r.dtype)
class Mapping:
"""
Baseclass to map red, blue, green intensities into uint8 values.
Parameters
----------
minimum : float or sequence(3)
Intensity that should be mapped to black (a scalar or array for R, G, B).
image : `~numpy.ndarray`, optional
An image used to calculate some parameters of some mappings.
"""
def __init__(self, minimum=None, image=None):
self._uint8Max = float(np.iinfo(np.uint8).max)
try:
len(minimum)
except TypeError:
minimum = 3*[minimum]
if len(minimum) != 3:
raise ValueError("please provide 1 or 3 values for minimum.")
self.minimum = minimum
self._image = np.asarray(image)
def make_rgb_image(self, image_r, image_g, image_b):
"""
Convert 3 arrays, image_r, image_g, and image_b into an 8-bit RGB image.
Parameters
----------
image_r : `~numpy.ndarray`
Image to map to red.
image_g : `~numpy.ndarray`
Image to map to green.
image_b : `~numpy.ndarray`
Image to map to blue.
Returns
-------
RGBimage : `~numpy.ndarray`
RGB (integer, 8-bits per channel) color image as an NxNx3 numpy array.
"""
image_r = np.asarray(image_r)
image_g = np.asarray(image_g)
image_b = np.asarray(image_b)
if (image_r.shape != image_g.shape) or (image_g.shape != image_b.shape):
msg = "The image shapes must match. r: {}, g: {} b: {}"
raise ValueError(msg.format(image_r.shape, image_g.shape, image_b.shape))
return np.dstack(self._convert_images_to_uint8(image_r, image_g, image_b)).astype(np.uint8)
def intensity(self, image_r, image_g, image_b):
"""
Return the total intensity from the red, blue, and green intensities.
This is a naive computation, and may be overridden by subclasses.
Parameters
----------
image_r : `~numpy.ndarray`
Intensity of image to be mapped to red; or total intensity if
``image_g`` and ``image_b`` are None.
image_g : `~numpy.ndarray`, optional
Intensity of image to be mapped to green.
image_b : `~numpy.ndarray`, optional
Intensity of image to be mapped to blue.
Returns
-------
intensity : `~numpy.ndarray`
Total intensity from the red, blue and green intensities, or
``image_r`` if green and blue images are not provided.
"""
return compute_intensity(image_r, image_g, image_b)
def map_intensity_to_uint8(self, I):
"""
Return an array which, when multiplied by an image, returns that image
mapped to the range of a uint8, [0, 255] (but not converted to uint8).
The intensity is assumed to have had minimum subtracted (as that can be
done per-band).
Parameters
----------
I : `~numpy.ndarray`
Intensity to be mapped.
Returns
-------
mapped_I : `~numpy.ndarray`
``I`` mapped to uint8
"""
with np.errstate(invalid='ignore', divide='ignore'):
return np.clip(I, 0, self._uint8Max)
def _convert_images_to_uint8(self, image_r, image_g, image_b):
"""Use the mapping to convert images image_r, image_g, and image_b to a triplet of uint8 images"""
image_r = image_r - self.minimum[0] # n.b. makes copy
image_g = image_g - self.minimum[1]
image_b = image_b - self.minimum[2]
fac = self.map_intensity_to_uint8(self.intensity(image_r, image_g, image_b))
image_rgb = [image_r, image_g, image_b]
for c in image_rgb:
c *= fac
c[c < 0] = 0 # individual bands can still be < 0, even if fac isn't
pixmax = self._uint8Max
r0, g0, b0 = image_rgb # copies -- could work row by row to minimise memory usage
with np.errstate(invalid='ignore', divide='ignore'): # n.b. np.where can't and doesn't short-circuit
for i, c in enumerate(image_rgb):
c = np.where(r0 > g0,
np.where(r0 > b0,
np.where(r0 >= pixmax, c*pixmax/r0, c),
np.where(b0 >= pixmax, c*pixmax/b0, c)),
np.where(g0 > b0,
np.where(g0 >= pixmax, c*pixmax/g0, c),
np.where(b0 >= pixmax, c*pixmax/b0, c))).astype(np.uint8)
c[c > pixmax] = pixmax
image_rgb[i] = c
return image_rgb
class LinearMapping(Mapping):
"""
A linear map map of red, blue, green intensities into uint8 values.
A linear stretch from [minimum, maximum].
If one or both are omitted use image min and/or max to set them.
Parameters
----------
minimum : float
Intensity that should be mapped to black (a scalar or array for R, G, B).
maximum : float
Intensity that should be mapped to white (a scalar).
"""
def __init__(self, minimum=None, maximum=None, image=None):
if minimum is None or maximum is None:
if image is None:
raise ValueError("you must provide an image if you don't "
"set both minimum and maximum")
if minimum is None:
minimum = image.min()
if maximum is None:
maximum = image.max()
Mapping.__init__(self, minimum=minimum, image=image)
self.maximum = maximum
if maximum is None:
self._range = None
else:
if maximum == minimum:
raise ValueError("minimum and maximum values must not be equal")
self._range = float(maximum - minimum)
def map_intensity_to_uint8(self, I):
with np.errstate(invalid='ignore', divide='ignore'): # n.b. np.where can't and doesn't short-circuit
return np.where(I <= 0, 0,
np.where(I >= self._range, self._uint8Max/I, self._uint8Max/self._range))
class AsinhMapping(Mapping):
"""
A mapping for an asinh stretch (preserving colours independent of brightness)
x = asinh(Q (I - minimum)/stretch)/Q
This reduces to a linear stretch if Q == 0
See http://adsabs.harvard.edu/abs/2004PASP..116..133L
Parameters
----------
minimum : float
Intensity that should be mapped to black (a scalar or array for R, G, B).
stretch : float
The linear stretch of the image.
Q : float
The asinh softening parameter.
"""
def __init__(self, minimum, stretch, Q=8):
Mapping.__init__(self, minimum)
epsilon = 1.0/2**23 # 32bit floating point machine epsilon; sys.float_info.epsilon is 64bit
if abs(Q) < epsilon:
Q = 0.1
else:
Qmax = 1e10
if Q > Qmax:
Q = Qmax
frac = 0.1 # gradient estimated using frac*stretch is _slope
self._slope = frac*self._uint8Max/np.arcsinh(frac*Q)
self._soften = Q/float(stretch)
def map_intensity_to_uint8(self, I):
with np.errstate(invalid='ignore', divide='ignore'): # n.b. np.where can't and doesn't short-circuit
return np.where(I <= 0, 0, np.arcsinh(I*self._soften)*self._slope/I)
class AsinhZScaleMapping(AsinhMapping):
"""
A mapping for an asinh stretch, estimating the linear stretch by zscale.
x = asinh(Q (I - z1)/(z2 - z1))/Q
Parameters
----------
image1 : `~numpy.ndarray` or a list of arrays
The image to analyse, or a list of 3 images to be converted to
an intensity image.
image2 : `~numpy.ndarray`, optional
the second image to analyse (must be specified with image3).
image3 : `~numpy.ndarray`, optional
the third image to analyse (must be specified with image2).
Q : float, optional
The asinh softening parameter. Default is 8.
pedestal : float or sequence(3), optional
The value, or array of 3 values, to subtract from the images; or None.
Notes
-----
pedestal, if not None, is removed from the images when calculating the
zscale stretch, and added back into Mapping.minimum[]
"""
def __init__(self, image1, image2=None, image3=None, Q=8, pedestal=None):
"""
"""
if image2 is None or image3 is None:
if not (image2 is None and image3 is None):
raise ValueError("please specify either a single image "
"or three images.")
image = [image1]
else:
image = [image1, image2, image3]
if pedestal is not None:
try:
len(pedestal)
except TypeError:
pedestal = 3*[pedestal]
if len(pedestal) != 3:
raise ValueError("please provide 1 or 3 pedestals.")
image = list(image) # needs to be mutable
for i, im in enumerate(image):
if pedestal[i] != 0.0:
image[i] = im - pedestal[i] # n.b. a copy
else:
pedestal = len(image)*[0.0]
image = compute_intensity(*image)
zscale_limits = ZScaleInterval().get_limits(image)
zscale = LinearMapping(*zscale_limits, image=image)
stretch = zscale.maximum - zscale.minimum[0] # zscale.minimum is always a triple
minimum = zscale.minimum
for i, level in enumerate(pedestal):
minimum[i] += level
AsinhMapping.__init__(self, minimum, stretch, Q)
self._image = image
def make_lupton_rgb(image_r, image_g, image_b, minimum=0, stretch=5, Q=8,
filename=None):
"""
Return a Red/Green/Blue color image from up to 3 images using an asinh stretch.
The input images can be int or float, and in any range or bit-depth.
For a more detailed look at the use of this method, see the document
:ref:`astropy-visualization-rgb`.
Parameters
----------
image_r : `~numpy.ndarray`
Image to map to red.
image_g : `~numpy.ndarray`
Image to map to green.
image_b : `~numpy.ndarray`
Image to map to blue.
minimum : float
Intensity that should be mapped to black (a scalar or array for R, G, B).
stretch : float
The linear stretch of the image.
Q : float
The asinh softening parameter.
filename: str
Write the resulting RGB image to a file (file type determined
from extension).
Returns
-------
rgb : `~numpy.ndarray`
RGB (integer, 8-bits per channel) color image as an NxNx3 numpy array.
"""
asinhMap = AsinhMapping(minimum, stretch, Q)
rgb = asinhMap.make_rgb_image(image_r, image_g, image_b)
if filename:
import matplotlib.image
matplotlib.image.imsave(filename, rgb, origin='lower')
return rgb
|
7c5f18f0515170ce20f5ce2735258550eb835fbfa63709386da68645918d6009 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Classes that deal with computing intervals from arrays of values based on
various criteria.
"""
import abc
import numpy as np
from ..utils.misc import InheritDocstrings
from .transform import BaseTransform
__all__ = ['BaseInterval', 'ManualInterval', 'MinMaxInterval',
'AsymmetricPercentileInterval', 'PercentileInterval',
'ZScaleInterval']
class BaseInterval(BaseTransform, metaclass=InheritDocstrings):
"""
Base class for the interval classes, which, when called with an
array of values, return an interval computed following different
algorithms.
"""
@abc.abstractmethod
def get_limits(self, values):
"""
Return the minimum and maximum value in the interval based on
the values provided.
Parameters
----------
values : `~numpy.ndarray`
The image values.
Returns
-------
vmin, vmax : float
The mininium and maximum image value in the interval.
"""
def __call__(self, values, clip=True, out=None):
"""
Transform values using this interval.
Parameters
----------
values : array-like
The input values.
clip : bool, optional
If `True` (default), values outside the [0:1] range are
clipped to the [0:1] range.
out : `~numpy.ndarray`, optional
If specified, the output values will be placed in this array
(typically used for in-place calculations).
Returns
-------
result : `~numpy.ndarray`
The transformed values.
"""
vmin, vmax = self.get_limits(values)
if out is None:
values = np.subtract(values, float(vmin))
else:
if out.dtype.kind != 'f':
raise TypeError('Can only do in-place scaling for '
'floating-point arrays')
values = np.subtract(values, float(vmin), out=out)
if (vmax - vmin) != 0:
np.true_divide(values, vmax - vmin, out=values)
if clip:
np.clip(values, 0., 1., out=values)
return values
class ManualInterval(BaseInterval):
"""
Interval based on user-specified values.
Parameters
----------
vmin : float, optional
The minimum value in the scaling. Defaults to the image
minimum (ignoring NaNs)
vmax : float, optional
The maximum value in the scaling. Defaults to the image
maximum (ignoring NaNs)
"""
def __init__(self, vmin=None, vmax=None):
self.vmin = vmin
self.vmax = vmax
def get_limits(self, values):
vmin = np.nanmin(values) if self.vmin is None else self.vmin
vmax = np.nanmax(values) if self.vmax is None else self.vmax
return vmin, vmax
class MinMaxInterval(BaseInterval):
"""
Interval based on the minimum and maximum values in the data.
"""
def get_limits(self, values):
return np.min(values), np.max(values)
class AsymmetricPercentileInterval(BaseInterval):
"""
Interval based on a keeping a specified fraction of pixels (can be
asymmetric).
Parameters
----------
lower_percentile : float
The lower percentile below which to ignore pixels.
upper_percentile : float
The upper percentile above which to ignore pixels.
n_samples : int, optional
Maximum number of values to use. If this is specified, and there
are more values in the dataset as this, then values are randomly
sampled from the array (with replacement).
"""
def __init__(self, lower_percentile, upper_percentile, n_samples=None):
self.lower_percentile = lower_percentile
self.upper_percentile = upper_percentile
self.n_samples = n_samples
def get_limits(self, values):
# Make sure values is a Numpy array
values = np.asarray(values).ravel()
# If needed, limit the number of samples. We sample with replacement
# since this is much faster.
if self.n_samples is not None and values.size > self.n_samples:
values = np.random.choice(values, self.n_samples)
# Filter out invalid values (inf, nan)
values = values[np.isfinite(values)]
# Determine values at percentiles
vmin, vmax = np.percentile(values, (self.lower_percentile,
self.upper_percentile))
return vmin, vmax
class PercentileInterval(AsymmetricPercentileInterval):
"""
Interval based on a keeping a specified fraction of pixels.
Parameters
----------
percentile : float
The fraction of pixels to keep. The same fraction of pixels is
eliminated from both ends.
n_samples : int, optional
Maximum number of values to use. If this is specified, and there
are more values in the dataset as this, then values are randomly
sampled from the array (with replacement).
"""
def __init__(self, percentile, n_samples=None):
lower_percentile = (100 - percentile) * 0.5
upper_percentile = 100 - lower_percentile
super().__init__(
lower_percentile, upper_percentile, n_samples=n_samples)
class ZScaleInterval(BaseInterval):
"""
Interval based on IRAF's zscale.
http://iraf.net/forum/viewtopic.php?showtopic=134139
Original implementation:
https://trac.stsci.edu/ssb/stsci_python/browser/stsci_python/trunk/numdisplay/lib/stsci/numdisplay/zscale.py?rev=19347
Licensed under a 3-clause BSD style license (see AURA_LICENSE.rst).
Parameters
----------
nsamples : int, optional
The number of points in the array to sample for determining
scaling factors. Defaults to 1000.
contrast : float, optional
The scaling factor (between 0 and 1) for determining the minimum
and maximum value. Larger values increase the difference
between the minimum and maximum values used for display.
Defaults to 0.25.
max_reject : float, optional
If more than ``max_reject * npixels`` pixels are rejected, then
the returned values are the minimum and maximum of the data.
Defaults to 0.5.
min_npixels : int, optional
If less than ``min_npixels`` pixels are rejected, then the
returned values are the minimum and maximum of the data.
Defaults to 5.
krej : float, optional
The number of sigma used for the rejection. Defaults to 2.5.
max_iterations : int, optional
The maximum number of iterations for the rejection. Defaults to
5.
"""
def __init__(self, nsamples=1000, contrast=0.25, max_reject=0.5,
min_npixels=5, krej=2.5, max_iterations=5):
self.nsamples = nsamples
self.contrast = contrast
self.max_reject = max_reject
self.min_npixels = min_npixels
self.krej = krej
self.max_iterations = max_iterations
def get_limits(self, values):
# Sample the image
values = np.asarray(values)
values = values[np.isfinite(values)]
stride = int(max(1.0, values.size / self.nsamples))
samples = values[::stride][:self.nsamples]
samples.sort()
npix = len(samples)
vmin = samples[0]
vmax = samples[-1]
# Fit a line to the sorted array of samples
minpix = max(self.min_npixels, int(npix * self.max_reject))
x = np.arange(npix)
ngoodpix = npix
last_ngoodpix = npix + 1
# Bad pixels mask used in k-sigma clipping
badpix = np.zeros(npix, dtype=bool)
# Kernel used to dilate the bad pixels mask
ngrow = max(1, int(npix * 0.01))
kernel = np.ones(ngrow, dtype=bool)
for niter in range(self.max_iterations):
if ngoodpix >= last_ngoodpix or ngoodpix < minpix:
break
fit = np.polyfit(x, samples, deg=1, w=(~badpix).astype(int))
fitted = np.poly1d(fit)(x)
# Subtract fitted line from the data array
flat = samples - fitted
# Compute the k-sigma rejection threshold
threshold = self.krej * flat[~badpix].std()
# Detect and reject pixels further than k*sigma from the
# fitted line
badpix[(flat < - threshold) | (flat > threshold)] = True
# Convolve with a kernel of length ngrow
badpix = np.convolve(badpix, kernel, mode='same')
last_ngoodpix = ngoodpix
ngoodpix = np.sum(~badpix)
slope, intercept = fit
if ngoodpix >= minpix:
if self.contrast > 0:
slope = slope / self.contrast
center_pixel = (npix - 1) // 2
median = np.median(samples)
vmin = max(vmin, median - (center_pixel - 1) * slope)
vmax = min(vmax, median + (npix - center_pixel) * slope)
return vmin, vmax
|
e38116d304a67be1a02ed55b378ff72f2907a4a020be24947efd0525f5f8170a | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
import numpy as np
__doctest_skip__ = ['quantity_support']
def quantity_support(format='latex_inline'):
"""
Enable support for plotting `astropy.units.Quantity` instances in
matplotlib.
May be (optionally) used with a ``with`` statement.
>>> import matplotlib.pyplot as plt
>>> from astropy import units as u
>>> from astropy import visualization
>>> with visualization.quantity_support():
... plt.figure()
... plt.plot([1, 2, 3] * u.m)
[...]
... plt.plot([101, 125, 150] * u.cm)
[...]
... plt.draw()
Parameters
----------
format : `astropy.units.format.Base` instance or str
The name of a format or a formatter object. If not
provided, defaults to ``latex_inline``.
"""
from .. import units as u
from matplotlib import units
from matplotlib import ticker
def rad_fn(x, pos=None):
n = int((x / np.pi) * 2.0 + 0.25)
if n == 0:
return '0'
elif n == 1:
return 'π/2'
elif n == 2:
return 'π'
elif n % 2 == 0:
return '{0}π'.format(n / 2)
else:
return '{0}π/2'.format(n)
class MplQuantityConverter(units.ConversionInterface):
def __init__(self):
if u.Quantity not in units.registry:
units.registry[u.Quantity] = self
self._remove = True
else:
self._remove = False
@staticmethod
def axisinfo(unit, axis):
if unit == u.radian:
return units.AxisInfo(
majloc=ticker.MultipleLocator(base=np.pi/2),
majfmt=ticker.FuncFormatter(rad_fn),
label=unit.to_string(),
)
elif unit == u.degree:
return units.AxisInfo(
majloc=ticker.AutoLocator(),
majfmt=ticker.FormatStrFormatter('%i°'),
label=unit.to_string(),
)
elif unit is not None:
return units.AxisInfo(label=unit.to_string(format))
return None
@staticmethod
def convert(val, unit, axis):
if isinstance(val, u.Quantity):
return val.to_value(unit)
else:
return val
@staticmethod
def default_units(x, axis):
if hasattr(x, 'unit'):
return x.unit
return None
def __enter__(self):
return self
def __exit__(self, type, value, tb):
if self._remove:
del units.registry[u.Quantity]
return MplQuantityConverter()
|
b0abdc7bd893ff5f0027ebc04a7c69251f3b874e8d97960398add4ba110763b9 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
# This module contains dictionaries that can be used to set a matplotlib
# plotting style. It is no longer documented/recommended as of Astropy v3.0
# but is kept here for backward-compatibility.
from ..utils import minversion
# This returns False if matplotlib cannot be imported
MATPLOTLIB_GE_1_5 = minversion('matplotlib', '1.5')
__all__ = ['astropy_mpl_style_1', 'astropy_mpl_style']
# Version 1 astropy plotting style for matplotlib
astropy_mpl_style_1 = {
# Lines
'lines.linewidth': 1.7,
'lines.antialiased': True,
# Patches
'patch.linewidth': 1.0,
'patch.facecolor': '#348ABD',
'patch.edgecolor': '#CCCCCC',
'patch.antialiased': True,
# Images
'image.cmap': 'gist_heat',
'image.origin': 'upper',
# Font
'font.size': 12.0,
# Axes
'axes.facecolor': '#FFFFFF',
'axes.edgecolor': '#AAAAAA',
'axes.linewidth': 1.0,
'axes.grid': True,
'axes.titlesize': 'x-large',
'axes.labelsize': 'large',
'axes.labelcolor': 'k',
'axes.axisbelow': True,
# Ticks
'xtick.major.size': 0,
'xtick.minor.size': 0,
'xtick.major.pad': 6,
'xtick.minor.pad': 6,
'xtick.color': '#565656',
'xtick.direction': 'in',
'ytick.major.size': 0,
'ytick.minor.size': 0,
'ytick.major.pad': 6,
'ytick.minor.pad': 6,
'ytick.color': '#565656',
'ytick.direction': 'in',
# Legend
'legend.fancybox': True,
'legend.loc': 'best',
# Figure
'figure.figsize': [8, 6],
'figure.facecolor': '1.0',
'figure.edgecolor': '0.50',
'figure.subplot.hspace': 0.5,
# Other
'savefig.dpi': 72,
}
color_cycle = ['#348ABD', # blue
'#7A68A6', # purple
'#A60628', # red
'#467821', # green
'#CF4457', # pink
'#188487', # turquoise
'#E24A33'] # orange
if MATPLOTLIB_GE_1_5:
# This is a dependency of matplotlib, so should be present.
from cycler import cycler
astropy_mpl_style_1['axes.prop_cycle'] = cycler('color', color_cycle)
else:
astropy_mpl_style_1['axes.color_cycle'] = color_cycle
astropy_mpl_style = astropy_mpl_style_1
"""The most recent version of the astropy plotting style."""
|
0abfe19ddf39a968ebbbe3cdf511b78225808bfa3da39354da2c59731f05e534 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
import numpy as np
from inspect import signature
from ..stats import histogram
__all__ = ['hist']
def hist(x, bins=10, ax=None, **kwargs):
"""Enhanced histogram function
This is a histogram function that enables the use of more sophisticated
algorithms for determining bins. Aside from the ``bins`` argument allowing
a string specified how bins are computed, the parameters are the same
as pylab.hist().
This function was ported from astroML: http://astroML.org/
Parameters
----------
x : array_like
array of data to be histogrammed
bins : int or list or str (optional)
If bins is a string, then it must be one of:
- 'blocks' : use bayesian blocks for dynamic bin widths
- 'knuth' : use Knuth's rule to determine bins
- 'scott' : use Scott's rule to determine bins
- 'freedman' : use the Freedman-diaconis rule to determine bins
ax : Axes instance (optional)
specify the Axes on which to draw the histogram. If not specified,
then the current active axes will be used.
**kwargs :
other keyword arguments are described in ``plt.hist()``.
Notes
-----
Return values are the same as for ``plt.hist()``
See Also
--------
astropy.stats.histogram
"""
# arguments of np.histogram should be passed to astropy.stats.histogram
arglist = list(signature(np.histogram).parameters.keys())[1:]
np_hist_kwds = dict((key, kwargs[key]) for key in arglist if key in kwargs)
hist, bins = histogram(x, bins, **np_hist_kwds)
if ax is None:
# optional dependency; only import if strictly needed.
import matplotlib.pyplot as plt
ax = plt.gca()
return ax.hist(x, bins, **kwargs)
|
6b6965debc48a24995e759e834954177a67be52af0259c37fe4cd51c3626581f | # Licensed under a 3-clause BSD style license - see LICENSE.rst
__all__ = ['BaseTransform', 'CompositeTransform']
class BaseTransform:
"""
A transformation object.
This is used to construct transformations such as scaling, stretching, and
so on.
"""
def __add__(self, other):
return CompositeTransform(other, self)
class CompositeTransform(BaseTransform):
"""
A combination of two transforms.
Parameters
----------
transform_1 : :class:`astropy.visualization.BaseTransform`
The first transform to apply.
transform_2 : :class:`astropy.visualization.BaseTransform`
The second transform to apply.
"""
def __init__(self, transform_1, transform_2):
super().__init__()
self.transform_1 = transform_1
self.transform_2 = transform_2
def __call__(self, values, clip=True):
return self.transform_2(self.transform_1(values, clip=clip), clip=clip)
@property
def inverse(self):
return CompositeTransform(self.transform_2.inverse,
self.transform_1.inverse)
|
1171f796d0900a9059332b5be21dfc91794d138d510f32b2b0f8d0a759131c52 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Classes that deal with stretching, i.e. mapping a range of [0:1] values onto
another set of [0:1] values with a transformation
"""
import numpy as np
from ..utils.misc import InheritDocstrings
from .transform import BaseTransform
__all__ = ["BaseStretch", "LinearStretch", "SqrtStretch", "PowerStretch",
"PowerDistStretch", "SquaredStretch", "LogStretch", "AsinhStretch",
"SinhStretch", "HistEqStretch", "ContrastBiasStretch"]
def _logn(n, x, out=None):
"""Calculate the log base n of x."""
# We define this because numpy.lib.scimath.logn doesn't support out=
if out is None:
return np.log(x) / np.log(n)
else:
np.log(x, out=out)
np.true_divide(out, np.log(n), out=out)
return out
def _prepare(values, clip=True, out=None):
"""
Prepare the data by optionally clipping and copying, and return the
array that should be subsequently used for in-place calculations.
"""
if clip:
return np.clip(values, 0., 1., out=out)
else:
if out is None:
return np.array(values, copy=True)
else:
out[:] = np.asarray(values)
return out
class BaseStretch(BaseTransform, metaclass=InheritDocstrings):
"""
Base class for the stretch classes, which, when called with an array
of values in the range [0:1], return an transformed array of values,
also in the range [0:1].
"""
def __call__(self, values, clip=True, out=None):
"""
Transform values using this stretch.
Parameters
----------
values : array-like
The input values, which should already be normalized to the
[0:1] range.
clip : bool, optional
If `True` (default), values outside the [0:1] range are
clipped to the [0:1] range.
out : `~numpy.ndarray`, optional
If specified, the output values will be placed in this array
(typically used for in-place calculations).
Returns
-------
result : `~numpy.ndarray`
The transformed values.
"""
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
class LinearStretch(BaseStretch):
"""
A linear stretch.
The stretch is given by:
.. math::
y = x
"""
def __call__(self, values, clip=True, out=None):
return _prepare(values, clip=clip, out=out)
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return LinearStretch()
class SqrtStretch(BaseStretch):
r"""
A square root stretch.
The stretch is given by:
.. math::
y = \sqrt{x}
"""
def __call__(self, values, clip=True, out=None):
values = _prepare(values, clip=clip, out=out)
np.sqrt(values, out=values)
return values
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return PowerStretch(2)
class PowerStretch(BaseStretch):
r"""
A power stretch.
The stretch is given by:
.. math::
y = x^a
Parameters
----------
a : float
The power index (see the above formula).
"""
def __init__(self, a):
super().__init__()
self.power = a
def __call__(self, values, clip=True, out=None):
values = _prepare(values, clip=clip, out=out)
np.power(values, self.power, out=values)
return values
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return PowerStretch(1. / self.power)
class PowerDistStretch(BaseStretch):
r"""
An alternative power stretch.
The stretch is given by:
.. math::
y = \frac{a^x - 1}{a - 1}
Parameters
----------
a : float, optional
The ``a`` parameter used in the above formula. Default is 1000.
``a`` cannot be set to 1.
"""
def __init__(self, a=1000.0):
if a == 1: # singularity
raise ValueError("a cannot be set to 1")
super().__init__()
self.exp = a
def __call__(self, values, clip=True, out=None):
values = _prepare(values, clip=clip, out=out)
np.power(self.exp, values, out=values)
np.subtract(values, 1, out=values)
np.true_divide(values, self.exp - 1.0, out=values)
return values
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return InvertedPowerDistStretch(a=self.exp)
class InvertedPowerDistStretch(BaseStretch):
r"""
Inverse transformation for
`~astropy.image.scaling.PowerDistStretch`.
The stretch is given by:
.. math::
y = \frac{\log(y (a-1) + 1)}{\log a}
Parameters
----------
a : float, optional
The ``a`` parameter used in the above formula. Default is 1000.
``a`` cannot be set to 1.
"""
def __init__(self, a=1000.0):
if a == 1: # singularity
raise ValueError("a cannot be set to 1")
super().__init__()
self.exp = a
def __call__(self, values, clip=True, out=None):
values = _prepare(values, clip=clip, out=out)
np.multiply(values, self.exp - 1.0, out=values)
np.add(values, 1, out=values)
_logn(self.exp, values, out=values)
return values
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return PowerDistStretch(a=self.exp)
class SquaredStretch(PowerStretch):
r"""
A convenience class for a power stretch of 2.
The stretch is given by:
.. math::
y = x^2
"""
def __init__(self):
super().__init__(2)
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return SqrtStretch()
class LogStretch(BaseStretch):
r"""
A log stretch.
The stretch is given by:
.. math::
y = \frac{\log{(a x + 1)}}{\log{(a + 1)}}.
Parameters
----------
a : float
The ``a`` parameter used in the above formula. Default is 1000.
"""
def __init__(self, a=1000.0):
super().__init__()
self.exp = a
def __call__(self, values, clip=True, out=None):
values = _prepare(values, clip=clip, out=out)
np.multiply(values, self.exp, out=values)
np.add(values, 1., out=values)
np.log(values, out=values)
np.true_divide(values, np.log(self.exp + 1.), out=values)
return values
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return InvertedLogStretch(self.exp)
class InvertedLogStretch(BaseStretch):
r"""
Inverse transformation for `~astropy.image.scaling.LogStretch`.
The stretch is given by:
.. math::
y = \frac{e^{y} (a + 1) -1}{a}
Parameters
----------
a : float, optional
The ``a`` parameter used in the above formula. Default is 1000.
"""
def __init__(self, a):
super().__init__()
self.exp = a
def __call__(self, values, clip=True, out=None):
values = _prepare(values, clip=clip, out=out)
np.multiply(values, np.log(self.exp + 1.), out=values)
np.exp(values, out=values)
np.subtract(values, 1., out=values)
np.true_divide(values, self.exp, out=values)
return values
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return LogStretch(self.exp)
class AsinhStretch(BaseStretch):
r"""
An asinh stretch.
The stretch is given by:
.. math::
y = \frac{{\rm asinh}(x / a)}{{\rm asinh}(1 / a)}.
Parameters
----------
a : float, optional
The ``a`` parameter used in the above formula. The value of
this parameter is where the asinh curve transitions from linear
to logarithmic behavior, expressed as a fraction of the
normalized image. Must be in the range between 0 and 1.
Default is 0.1
"""
def __init__(self, a=0.1):
super().__init__()
self.a = a
def __call__(self, values, clip=True, out=None):
values = _prepare(values, clip=clip, out=out)
np.true_divide(values, self.a, out=values)
np.arcsinh(values, out=values)
np.true_divide(values, np.arcsinh(1. / self.a), out=values)
return values
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return SinhStretch(a=1. / np.arcsinh(1. / self.a))
class SinhStretch(BaseStretch):
r"""
A sinh stretch.
The stretch is given by:
.. math::
y = \frac{{\rm sinh}(x / a)}{{\rm sinh}(1 / a)}
Parameters
----------
a : float, optional
The ``a`` parameter used in the above formula. Default is 1/3.
"""
def __init__(self, a=1./3.):
super().__init__()
self.a = a
def __call__(self, values, clip=True, out=None):
values = _prepare(values, clip=clip, out=out)
np.true_divide(values, self.a, out=values)
np.sinh(values, out=values)
np.true_divide(values, np.sinh(1. / self.a), out=values)
return values
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return AsinhStretch(a=1. / np.sinh(1. / self.a))
class HistEqStretch(BaseStretch):
"""
A histogram equalization stretch.
Parameters
----------
data : array-like
The data defining the equalization.
values : array-like, optional
The input image values, which should already be normalized to
the [0:1] range.
"""
def __init__(self, data, values=None):
# Assume data is not necessarily normalized at this point
self.data = np.sort(data.ravel())
vmin = self.data.min()
vmax = self.data.max()
self.data = (self.data - vmin) / (vmax - vmin)
# Compute relative position of each pixel
if values is None:
self.values = np.linspace(0., 1., len(self.data))
else:
self.values = values
def __call__(self, values, clip=True, out=None):
values = _prepare(values, clip=clip, out=out)
values[:] = np.interp(values, self.data, self.values)
return values
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return InvertedHistEqStretch(self.data, values=self.values)
class InvertedHistEqStretch(BaseStretch):
"""
Inverse transformation for `~astropy.image.scaling.HistEqStretch`.
Parameters
----------
data : array-like
The data defining the equalization.
values : array-like, optional
The input image values, which should already be normalized to
the [0:1] range.
"""
def __init__(self, data, values=None):
self.data = data
if values is None:
self.values = np.linspace(0., 1., len(self.data))
else:
self.values = values
def __call__(self, values, clip=True, out=None):
values = _prepare(values, clip=clip, out=out)
values[:] = np.interp(values, self.values, self.data)
return values
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return HistEqStretch(self.data, values=self.values)
class ContrastBiasStretch(BaseStretch):
r"""
A stretch that takes into account contrast and bias.
The stretch is given by:
.. math::
y = (x - {\rm bias}) * {\rm contrast} + 0.5
and the output values are clipped to the [0:1] range.
Parameters
----------
contrast : float
The contrast parameter (see the above formula).
bias : float
The bias parameter (see the above formula).
"""
def __init__(self, contrast, bias):
super().__init__()
self.contrast = contrast
self.bias = bias
def __call__(self, values, clip=True, out=None):
# As a special case here, we only clip *after* the
# transformation since it does not map [0:1] to [0:1]
values = _prepare(values, clip=False, out=out)
np.subtract(values, self.bias, out=values)
np.multiply(values, self.contrast, out=values)
np.add(values, 0.5, out=values)
if clip:
np.clip(values, 0, 1, out=values)
return values
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return InvertedContrastBiasStretch(self.contrast, self.bias)
class InvertedContrastBiasStretch(BaseStretch):
"""
Inverse transformation for ContrastBiasStretch.
Parameters
----------
contrast : float
The contrast parameter (see
`~astropy.visualization.ConstrastBiasStretch).
bias : float
The bias parameter (see
`~astropy.visualization.ConstrastBiasStretch).
"""
def __init__(self, contrast, bias):
super().__init__()
self.contrast = contrast
self.bias = bias
def __call__(self, values, clip=True, out=None):
# As a special case here, we only clip *after* the
# transformation since it does not map [0:1] to [0:1]
values = _prepare(values, clip=False, out=out)
np.subtract(values, 0.5, out=values)
np.true_divide(values, self.contrast, out=values)
np.add(values, self.bias, out=values)
if clip:
np.clip(values, 0, 1, out=values)
return values
@property
def inverse(self):
"""A stretch object that performs the inverse operation."""
return ContrastBiasStretch(self.contrast, self.bias)
|
fb0c2f215cb928a11ea34cc823a7593256d34509ed0f4c610f4cca5f3d90b669 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
from copy import deepcopy
from inspect import signature
from itertools import islice
import warnings
from ..utils import wraps
from ..utils.exceptions import AstropyUserWarning
from .nddata import NDData
__all__ = ['support_nddata']
# All supported properties are optional except "data" which is mandatory!
SUPPORTED_PROPERTIES = ['data', 'uncertainty', 'mask', 'meta', 'unit', 'wcs',
'flags']
def support_nddata(_func=None, accepts=NDData,
repack=False, returns=None, keeps=None,
**attribute_argument_mapping):
"""Decorator to wrap functions that could accept an NDData instance with
its properties passed as function arguments.
Parameters
----------
_func : callable, None, optional
The function to decorate or ``None`` if used as factory. The first
positional argument should be ``data`` and take a numpy array. It is
possible to overwrite the name, see ``attribute_argument_mapping``
argument.
Default is ``None``.
accepts : cls, optional
The class or subclass of ``NDData`` that should be unpacked before
calling the function.
Default is ``NDData``
repack : bool, optional
Should be ``True`` if the return should be converted to the input
class again after the wrapped function call.
Default is ``False``.
.. note::
Must be ``True`` if either one of ``returns`` or ``keeps``
is specified.
returns : iterable, None, optional
An iterable containing strings which returned value should be set
on the class. For example if a function returns data and mask, this
should be ``['data', 'mask']``. If ``None`` assume the function only
returns one argument: ``'data'``.
Default is ``None``.
.. note::
Must be ``None`` if ``repack=False``.
keeps : iterable. None, optional
An iterable containing strings that indicate which values should be
copied from the original input to the returned class. If ``None``
assume that no attributes are copied.
Default is ``None``.
.. note::
Must be ``None`` if ``repack=False``.
attribute_argument_mapping :
Keyword parameters that optionally indicate which function argument
should be interpreted as which attribute on the input. By default
it assumes the function takes a ``data`` argument as first argument,
but if the first argument is called ``input`` one should pass
``support_nddata(..., data='input')`` to the function.
Returns
-------
decorator_factory or decorated_function : callable
If ``_func=None`` this returns a decorator, otherwise it returns the
decorated ``_func``.
Notes
-----
If properties of ``NDData`` are set but have no corresponding function
argument a Warning is shown.
If a property is set of the ``NDData`` are set and an explicit argument is
given, the explicitly given argument is used and a Warning is shown.
The supported properties are:
- ``mask``
- ``unit``
- ``wcs``
- ``meta``
- ``uncertainty``
- ``flags``
Examples
--------
This function takes a Numpy array for the data, and some WCS information
with the ``wcs`` keyword argument::
def downsample(data, wcs=None):
# downsample data and optionally WCS here
pass
However, you might have an NDData instance that has the ``wcs`` property
set and you would like to be able to call the function with
``downsample(my_nddata)`` and have the WCS information, if present,
automatically be passed to the ``wcs`` keyword argument.
This decorator can be used to make this possible::
@support_nddata
def downsample(data, wcs=None):
# downsample data and optionally WCS here
pass
This function can now either be called as before, specifying the data and
WCS separately, or an NDData instance can be passed to the ``data``
argument.
"""
if (returns is not None or keeps is not None) and not repack:
raise ValueError('returns or keeps should only be set if repack=True.')
elif returns is None and repack:
raise ValueError('returns should be set if repack=True.')
else:
# Use empty lists for returns and keeps so we don't need to check
# if any of those is None later on.
if returns is None:
returns = []
if keeps is None:
keeps = []
# Short version to avoid the long variable name later.
attr_arg_map = attribute_argument_mapping
if any(keep in returns for keep in keeps):
raise ValueError("cannot specify the same attribute in `returns` and "
"`keeps`.")
all_returns = returns + keeps
def support_nddata_decorator(func):
# Find out args and kwargs
func_args, func_kwargs = [], []
sig = signature(func).parameters
for param_name, param in sig.items():
if param.kind in (param.VAR_POSITIONAL, param.VAR_KEYWORD):
raise ValueError("func may not have *args or **kwargs.")
try:
if param.default == param.empty:
func_args.append(param_name)
else:
func_kwargs.append(param_name)
# The comparison to param.empty may fail if the default is a
# numpy array or something similar. So if the comparison fails then
# it's quite obvious that there was a default and it should be
# appended to the "func_kwargs".
except ValueError as exc:
if ('The truth value of an array with more than one element '
'is ambiguous.') in str(exc):
func_kwargs.append(param_name)
else:
raise
# First argument should be data
if not func_args or func_args[0] != attr_arg_map.get('data', 'data'):
raise ValueError("Can only wrap functions whose first positional "
"argument is `{0}`"
"".format(attr_arg_map.get('data', 'data')))
@wraps(func)
def wrapper(data, *args, **kwargs):
unpack = isinstance(data, accepts)
input_data = data
ignored = []
if not unpack and isinstance(data, NDData):
raise TypeError("Only NDData sub-classes that inherit from {0}"
" can be used by this function"
"".format(accepts.__name__))
# If data is an NDData instance, we can try and find properties
# that can be passed as kwargs.
if unpack:
# We loop over a list of pre-defined properties
for prop in islice(SUPPORTED_PROPERTIES, 1, None):
# We only need to do something if the property exists on
# the NDData object
try:
value = getattr(data, prop)
except AttributeError:
continue
# Skip if the property exists but is None or empty.
if prop == 'meta' and not value:
continue
elif value is None:
continue
# Warn if the property is set but not used by the function.
propmatch = attr_arg_map.get(prop, prop)
if propmatch not in func_kwargs:
ignored.append(prop)
continue
# Check if the property was explicitly given and issue a
# Warning if it is.
if propmatch in kwargs:
# If it's in the func_args it's trivial but if it was
# in the func_kwargs we need to compare it to the
# default.
# Comparison to the default is done by comparing their
# identity, this works because defaults in function
# signatures are only created once and always reference
# the same item.
# FIXME: Python interns some values, for example the
# integers from -5 to 255 (any maybe some other types
# as well). In that case the default is
# indistinguishable from an explicitly passed kwarg
# and it won't notice that and use the attribute of the
# NDData.
if (propmatch in func_args or
(propmatch in func_kwargs and
(kwargs[propmatch] is not
sig[propmatch].default))):
warnings.warn(
"Property {0} has been passed explicitly and "
"as an NDData property{1}, using explicitly "
"specified value"
"".format(propmatch, '' if prop == propmatch
else ' ' + prop),
AstropyUserWarning)
continue
# Otherwise use the property as input for the function.
kwargs[propmatch] = value
# Finally, replace data by the data attribute
data = data.data
if ignored:
warnings.warn("The following attributes were set on the "
"data object, but will be ignored by the "
"function: " + ", ".join(ignored),
AstropyUserWarning)
result = func(data, *args, **kwargs)
if unpack and repack:
# If there are multiple required returned arguments make sure
# the result is a tuple (because we don't want to unpack
# numpy arrays or compare their length, never!) and has the
# same length.
if len(returns) > 1:
if (not isinstance(result, tuple) or
len(returns) != len(result)):
raise ValueError("Function did not return the "
"expected number of arguments.")
elif len(returns) == 1:
result = [result]
if keeps is not None:
for keep in keeps:
result.append(deepcopy(getattr(input_data, keep)))
resultdata = result[all_returns.index('data')]
resultkwargs = {ret: res
for ret, res in zip(all_returns, result)
if ret != 'data'}
return input_data.__class__(resultdata, **resultkwargs)
else:
return result
return wrapper
# If _func is set, this means that the decorator was used without
# parameters so we have to return the result of the
# support_nddata_decorator decorator rather than the decorator itself
if _func is not None:
return support_nddata_decorator(_func)
else:
return support_nddata_decorator
|
7e6f0186b4d61278a1a70ab055b5827f5ef23896c7e376434efce07293ab5acd | # Licensed under a 3-clause BSD style license - see LICENSE.rst
# This module implements the base NDDataBase class.
from abc import ABCMeta, abstractmethod
__all__ = ['NDDataBase']
class NDDataBase(metaclass=ABCMeta):
"""Base metaclass that defines the interface for N-dimensional datasets
with associated meta information used in ``astropy``.
All properties and ``__init__`` have to be overridden in subclasses. See
`NDData` for a subclass that defines this interface on `numpy.ndarray`-like
``data``.
"""
@abstractmethod
def __init__(self):
pass
@property
@abstractmethod
def data(self):
"""The stored dataset.
"""
pass
@property
@abstractmethod
def mask(self):
"""Mask for the dataset.
Masks should follow the ``numpy`` convention that **valid** data points
are marked by ``False`` and **invalid** ones with ``True``.
"""
return None
@property
@abstractmethod
def unit(self):
"""Unit for the dataset.
"""
return None
@property
@abstractmethod
def wcs(self):
"""World coordinate system (WCS) for the dataset.
"""
return None
@property
@abstractmethod
def meta(self):
"""Additional meta information about the dataset.
Should be `dict`-like.
"""
return None
@property
@abstractmethod
def uncertainty(self):
"""Uncertainty in the dataset.
Should have an attribute ``uncertainty_type`` that defines what kind of
uncertainty is stored, such as ``"std"`` for standard deviation or
``"var"`` for variance.
"""
return None
|
b7733432be3aa6d7f548514e6a43889f3a7cba7f64c40a88390f60dcbc105a7b | # Licensed under a 3-clause BSD style license - see LICENSE.rst
import numpy as np
from abc import ABCMeta, abstractmethod
from copy import deepcopy
import weakref
# from ..utils.compat import ignored
from .. import log
from ..units import Unit, Quantity
__all__ = ['MissingDataAssociationException',
'IncompatibleUncertaintiesException', 'NDUncertainty',
'StdDevUncertainty', 'UnknownUncertainty']
class IncompatibleUncertaintiesException(Exception):
"""This exception should be used to indicate cases in which uncertainties
with two different classes can not be propagated.
"""
class MissingDataAssociationException(Exception):
"""This exception should be used to indicate that an uncertainty instance
has not been associated with a parent `~astropy.nddata.NDData` object.
"""
class NDUncertainty(metaclass=ABCMeta):
"""This is the metaclass for uncertainty classes used with `NDData`.
Parameters
----------
array : any type, optional
The array or value (the parameter name is due to historical reasons) of
the uncertainty. `numpy.ndarray`, `~astropy.units.Quantity` or
`NDUncertainty` subclasses are recommended.
If the `array` is `list`-like or `numpy.ndarray`-like it will be cast
to a plain `numpy.ndarray`.
Default is ``None``.
unit : `~astropy.units.Unit` or str, optional
Unit for the uncertainty ``array``. Strings that can be converted to a
`~astropy.units.Unit` are allowed.
Default is ``None``.
copy : `bool`, optional
Indicates whether to save the `array` as a copy. ``True`` copies it
before saving, while ``False`` tries to save every parameter as
reference. Note however that it is not always possible to save the
input as reference.
Default is ``True``.
Raises
------
IncompatibleUncertaintiesException
If given another `NDUncertainty`-like class as ``array`` if their
``uncertainty_type`` is different.
"""
def __init__(self, array=None, copy=True, unit=None):
if isinstance(array, NDUncertainty):
# Given an NDUncertainty class or subclass check that the type
# is the same.
if array.uncertainty_type != self.uncertainty_type:
raise IncompatibleUncertaintiesException
# Check if two units are given and take the explicit one then.
if (unit is not None and unit != array._unit):
# TODO : Clarify it (see NDData.init for same problem)?
log.info("overwriting Uncertainty's current "
"unit with specified unit.")
elif array._unit is not None:
unit = array.unit
array = array.array
elif isinstance(array, Quantity):
# Check if two units are given and take the explicit one then.
if (unit is not None and array.unit is not None and
unit != array.unit):
log.info("overwriting Quantity's current "
"unit with specified unit.")
elif array.unit is not None:
unit = array.unit
array = array.value
if unit is None:
self._unit = None
else:
self._unit = Unit(unit)
if copy:
array = deepcopy(array)
unit = deepcopy(unit)
self.array = array
self.parent_nddata = None # no associated NDData - until it is set!
@property
@abstractmethod
def uncertainty_type(self):
"""`str` : Short description of the type of uncertainty.
Defined as abstract property so subclasses *have* to override this.
"""
return None
@property
def supports_correlated(self):
"""`bool` : Supports uncertainty propagation with correlated \
uncertainties?
.. versionadded:: 1.2
"""
return False
@property
def array(self):
"""`numpy.ndarray` : the uncertainty's value.
"""
return self._array
@array.setter
def array(self, value):
if isinstance(value, (list, np.ndarray)):
value = np.array(value, subok=False, copy=False)
self._array = value
@property
def unit(self):
"""`~astropy.units.Unit` : The unit of the uncertainty, if any.
Even though it is not enforced the unit should be convertible to the
``parent_nddata`` unit. Otherwise uncertainty propagation might give
wrong results.
If the unit is not set the unit of the parent will be returned.
"""
if self._unit is None:
if (self._parent_nddata is None or
self.parent_nddata.unit is None):
return None
else:
return self.parent_nddata.unit
return self._unit
@property
def parent_nddata(self):
"""`NDData` : reference to `NDData` instance with this uncertainty.
In case the reference is not set uncertainty propagation will not be
possible since propagation might need the uncertain data besides the
uncertainty.
"""
message = "uncertainty is not associated with an NDData object"
try:
if self._parent_nddata is None:
raise MissingDataAssociationException(message)
else:
# The NDData is saved as weak reference so we must call it
# to get the object the reference points to.
if isinstance(self._parent_nddata, weakref.ref):
return self._parent_nddata()
else:
log.info("parent_nddata should be a weakref to an NDData "
"object.")
return self._parent_nddata
except AttributeError:
raise MissingDataAssociationException(message)
@parent_nddata.setter
def parent_nddata(self, value):
if value is not None and not isinstance(value, weakref.ref):
# Save a weak reference on the uncertainty that points to this
# instance of NDData. Direct references should NOT be used:
# https://github.com/astropy/astropy/pull/4799#discussion_r61236832
value = weakref.ref(value)
self._parent_nddata = value
def __repr__(self):
prefix = self.__class__.__name__ + '('
try:
body = np.array2string(self.array, separator=', ', prefix=prefix)
except AttributeError:
# In case it wasn't possible to use array2string
body = str(self.array)
return ''.join([prefix, body, ')'])
def __getitem__(self, item):
"""Normal slicing on the array, keep the unit and return a reference.
"""
return self.__class__(self.array[item], unit=self.unit, copy=False)
def propagate(self, operation, other_nddata, result_data, correlation):
"""Calculate the resulting uncertainty given an operation on the data.
.. versionadded:: 1.2
Parameters
----------
operation : callable
The operation that is performed on the `NDData`. Supported are
`numpy.add`, `numpy.subtract`, `numpy.multiply` and
`numpy.true_divide` (or `numpy.divide`).
other_nddata : `NDData` instance
The second operand in the arithmetic operation.
result_data : `~astropy.units.Quantity` or `numpy.ndarray`
The result of the arithmetic operations on the data.
correlation : `numpy.ndarray` or number
The correlation (rho) is defined between the uncertainties in
sigma_AB = sigma_A * sigma_B * rho. A value of ``0`` means
uncorrelated operands.
Returns
-------
resulting_uncertainty : `NDUncertainty` instance
Another instance of the same `NDUncertainty` subclass containing
the uncertainty of the result.
Raises
------
ValueError
If the ``operation`` is not supported or if correlation is not zero
but the subclass does not support correlated uncertainties.
Notes
-----
First this method checks if a correlation is given and the subclass
implements propagation with correlated uncertainties.
Then the second uncertainty is converted (or an Exception is raised)
to the same class in order to do the propagation.
Then the appropriate propagation method is invoked and the result is
returned.
"""
# Check if the subclass supports correlation
if not self.supports_correlated:
if isinstance(correlation, np.ndarray) or correlation != 0:
raise ValueError("{0} does not support uncertainty propagation"
" with correlation."
"".format(self.__class__.__name__))
# Get the other uncertainty (and convert it to a matching one)
other_uncert = self._convert_uncertainty(other_nddata.uncertainty)
if operation.__name__ == 'add':
result = self._propagate_add(other_uncert, result_data,
correlation)
elif operation.__name__ == 'subtract':
result = self._propagate_subtract(other_uncert, result_data,
correlation)
elif operation.__name__ == 'multiply':
result = self._propagate_multiply(other_uncert, result_data,
correlation)
elif operation.__name__ in ['true_divide', 'divide']:
result = self._propagate_divide(other_uncert, result_data,
correlation)
else:
raise ValueError('unsupported operation')
return self.__class__(result, copy=False)
def _convert_uncertainty(self, other_uncert):
"""Checks if the uncertainties are compatible for propagation.
Checks if the other uncertainty is `NDUncertainty`-like and if so
verify that the uncertainty_type is equal. If the latter is not the
case try returning ``self.__class__(other_uncert)``.
Parameters
----------
other_uncert : `NDUncertainty` subclass
The other uncertainty.
Returns
-------
other_uncert : `NDUncertainty` subclass
but converted to a compatible `NDUncertainty` subclass if
possible and necessary.
Raises
------
IncompatibleUncertaintiesException:
If the other uncertainty cannot be converted to a compatible
`NDUncertainty` subclass.
"""
if isinstance(other_uncert, NDUncertainty):
if self.uncertainty_type == other_uncert.uncertainty_type:
return other_uncert
else:
return self.__class__(other_uncert)
else:
raise IncompatibleUncertaintiesException
@abstractmethod
def _propagate_add(self, other_uncert, result_data, correlation):
return None
@abstractmethod
def _propagate_subtract(self, other_uncert, result_data, correlation):
return None
@abstractmethod
def _propagate_multiply(self, other_uncert, result_data, correlation):
return None
@abstractmethod
def _propagate_divide(self, other_uncert, result_data, correlation):
return None
class UnknownUncertainty(NDUncertainty):
"""This class implements any unknown uncertainty type.
The main purpose of having an unknown uncertainty class is to prevent
uncertainty propagation.
Parameters
----------
args, kwargs :
see `NDUncertainty`
"""
@property
def supports_correlated(self):
"""`False` : Uncertainty propagation is *not* possible for this class.
"""
return False
@property
def uncertainty_type(self):
"""``"unknown"`` : `UnknownUncertainty` implements any unknown \
uncertainty type.
"""
return 'unknown'
def _convert_uncertainty(self, other_uncert):
"""Raise an Exception because unknown uncertainty types cannot
implement propagation.
"""
msg = "Uncertainties of unknown type cannot be propagated."
raise IncompatibleUncertaintiesException(msg)
def _propagate_add(self, other_uncert, result_data, correlation):
"""Not possible for unknown uncertainty types.
"""
return None
def _propagate_subtract(self, other_uncert, result_data, correlation):
return None
def _propagate_multiply(self, other_uncert, result_data, correlation):
return None
def _propagate_divide(self, other_uncert, result_data, correlation):
return None
class StdDevUncertainty(NDUncertainty):
"""Standard deviation uncertainty assuming first order gaussian error
propagation.
This class implements uncertainty propagation for ``addition``,
``subtraction``, ``multiplication`` and ``division`` with other instances
of `StdDevUncertainty`. The class can handle if the uncertainty has a
unit that differs from (but is convertible to) the parents `NDData` unit.
The unit of the resulting uncertainty will have the same unit as the
resulting data. Also support for correlation is possible but requires the
correlation as input. It cannot handle correlation determination itself.
Parameters
----------
args, kwargs :
see `NDUncertainty`
Examples
--------
`StdDevUncertainty` should always be associated with an `NDData`-like
instance, either by creating it during initialization::
>>> from astropy.nddata import NDData, StdDevUncertainty
>>> ndd = NDData([1,2,3],
... uncertainty=StdDevUncertainty([0.1, 0.1, 0.1]))
>>> ndd.uncertainty # doctest: +FLOAT_CMP
StdDevUncertainty([0.1, 0.1, 0.1])
or by setting it manually on the `NDData` instance::
>>> ndd.uncertainty = StdDevUncertainty([0.2], unit='m', copy=True)
>>> ndd.uncertainty # doctest: +FLOAT_CMP
StdDevUncertainty([0.2])
the uncertainty ``array`` can also be set directly::
>>> ndd.uncertainty.array = 2
>>> ndd.uncertainty
StdDevUncertainty(2)
.. note::
The unit will not be displayed.
"""
@property
def supports_correlated(self):
"""`True` : `StdDevUncertainty` allows to propagate correlated \
uncertainties.
``correlation`` must be given, this class does not implement computing
it by itself.
"""
return True
@property
def uncertainty_type(self):
"""``"std"`` : `StdDevUncertainty` implements standard deviation.
"""
return 'std'
def _convert_uncertainty(self, other_uncert):
if isinstance(other_uncert, StdDevUncertainty):
return other_uncert
else:
raise IncompatibleUncertaintiesException
def _propagate_add(self, other_uncert, result_data, correlation):
if self.array is None:
# Formula: sigma = dB
if other_uncert.unit is not None and (
result_data.unit != other_uncert.unit):
# If the other uncertainty has a unit and this unit differs
# from the unit of the result convert it to the results unit
return (other_uncert.array * other_uncert.unit).to(
result_data.unit).value
else:
# Copy the result because _propagate will not copy it but for
# arithmetic operations users will expect copies.
return deepcopy(other_uncert.array)
elif other_uncert.array is None:
# Formula: sigma = dA
if self.unit is not None and self.unit != self.parent_nddata.unit:
# If the uncertainty has a different unit than the result we
# need to convert it to the results unit.
return self.unit.to(result_data.unit, self.array)
else:
# Copy the result because _propagate will not copy it but for
# arithmetic operations users will expect copies.
return deepcopy(self.array)
else:
# Formula: sigma = sqrt(dA**2 + dB**2 + 2*cor*dA*dB)
# Calculate: dA (this) and dB (other)
if self.unit != other_uncert.unit:
# In case the two uncertainties (or data) have different units
# we need to use quantity operations. The case where only one
# has a unit and the other doesn't is not possible with
# addition and would have raised an exception in the data
# computation
this = self.array * self.unit
other = other_uncert.array * other_uncert.unit
else:
# Since both units are the same or None we can just use
# numpy operations
this = self.array
other = other_uncert.array
# Determine the result depending on the correlation
if isinstance(correlation, np.ndarray) or correlation != 0:
corr = 2 * correlation * this * other
result = np.sqrt(this**2 + other**2 + corr)
else:
result = np.sqrt(this**2 + other**2)
if isinstance(result, Quantity):
# In case we worked with quantities we need to return the
# uncertainty that has the same unit as the resulting data.
# Note that this call is fast if the units are the same.
return result.to_value(result_data.unit)
else:
return result
def _propagate_subtract(self, other_uncert, result_data, correlation):
# Since the formulas are equivalent to addition you should look at the
# explanations provided in _propagate_add
if self.array is None:
if other_uncert.unit is not None and (
result_data.unit != other_uncert.unit):
return (other_uncert.array * other_uncert.unit).to(
result_data.unit).value
else:
return deepcopy(other_uncert.array)
elif other_uncert.array is None:
if self.unit is not None and self.unit != self.parent_nddata.unit:
return self.unit.to(result_data.unit, self.array)
else:
return deepcopy(self.array)
else:
# Formula: sigma = sqrt(dA**2 + dB**2 - 2*cor*dA*dB)
if self.unit != other_uncert.unit:
this = self.array * self.unit
other = other_uncert.array * other_uncert.unit
else:
this = self.array
other = other_uncert.array
if isinstance(correlation, np.ndarray) or correlation != 0:
corr = 2 * correlation * this * other
# The only difference to addition is that the correlation is
# subtracted.
result = np.sqrt(this**2 + other**2 - corr)
else:
result = np.sqrt(this**2 + other**2)
if isinstance(result, Quantity):
return result.to_value(result_data.unit)
else:
return result
def _propagate_multiply(self, other_uncert, result_data, correlation):
# For multiplication we don't need the result as quantity
if isinstance(result_data, Quantity):
result_data = result_data.value
if self.array is None:
# Formula: sigma = |A| * dB
# We want the result to have the same unit as the parent, so we
# only need to convert the unit of the other uncertainty if it is
# different from its data's unit.
if other_uncert.unit != other_uncert.parent_nddata.unit:
other = (other_uncert.array * other_uncert.unit).to(
other_uncert.parent_nddata.unit).value
else:
other = other_uncert.array
return np.abs(self.parent_nddata.data * other)
elif other_uncert.array is None:
# Formula: sigma = dA * |B|
# Just the reversed case
if self.unit != self.parent_nddata.unit:
this = (self.array * self.unit).to(
self.parent_nddata.unit).value
else:
this = self.array
return np.abs(other_uncert.parent_nddata.data * this)
else:
# Formula: sigma = |AB|*sqrt((dA/A)**2+(dB/B)**2+2*dA/A*dB/B*cor)
# This formula is not very handy since it generates NaNs for every
# zero in A and B. So we rewrite it:
# Formula: sigma = sqrt((dA*B)**2 + (dB*A)**2 + (2 * cor * ABdAdB))
# Calculate: dA * B (left)
if self.unit != self.parent_nddata.unit:
# To get the unit right we need to convert the unit of
# each uncertainty to the same unit as it's parent
left = ((self.array * self.unit).to(
self.parent_nddata.unit).value *
other_uncert.parent_nddata.data)
else:
left = self.array * other_uncert.parent_nddata.data
# Calculate: dB * A (right)
if other_uncert.unit != other_uncert.parent_nddata.unit:
right = ((other_uncert.array * other_uncert.unit).to(
other_uncert.parent_nddata.unit).value *
self.parent_nddata.data)
else:
right = other_uncert.array * self.parent_nddata.data
if isinstance(correlation, np.ndarray) or correlation != 0:
corr = (2 * correlation * left * right)
return np.sqrt(left**2 + right**2 + corr)
else:
return np.sqrt(left**2 + right**2)
def _propagate_divide(self, other_uncert, result_data, correlation):
# For division we don't need the result as quantity
if isinstance(result_data, Quantity):
result_data = result_data.value
if self.array is None:
# Formula: sigma = |(A / B) * (dB / B)|
# Calculate: dB / B (right)
if other_uncert.unit != other_uncert.parent_nddata.unit:
# We need (dB / B) to be dimensionless so we convert
# (if necessary) dB to the same unit as B
right = ((other_uncert.array * other_uncert.unit).to(
other_uncert.parent_nddata.unit).value /
other_uncert.parent_nddata.data)
else:
right = (other_uncert.array / other_uncert.parent_nddata.data)
return np.abs(result_data * right)
elif other_uncert.array is None:
# Formula: sigma = dA / |B|.
# Calculate: dA
if self.unit != self.parent_nddata.unit:
# We need to convert dA to the unit of A to have a result that
# matches the resulting data's unit.
left = (self.array * self.unit).to(
self.parent_nddata.unit).value
else:
left = self.array
return np.abs(left / other_uncert.parent_nddata.data)
else:
# Formula: sigma = |A/B|*sqrt((dA/A)**2+(dB/B)**2-2*dA/A*dB/B*cor)
# As with multiplication this formula creates NaNs where A is zero.
# So I'll rewrite it again:
# => sigma = sqrt((dA/B)**2 + (AdB/B**2)**2 - 2*cor*AdAdB/B**3)
# So we need to calculate dA/B in the same units as the result
# and the dimensionless dB/B to get a resulting uncertainty with
# the same unit as the data.
# Calculate: dA/B (left)
if self.unit != self.parent_nddata.unit:
left = ((self.array * self.unit).to(
self.parent_nddata.unit).value /
other_uncert.parent_nddata.data)
else:
left = self.array / other_uncert.parent_nddata.data
# Calculate: dB/B (right)
if other_uncert.unit != other_uncert.parent_nddata.unit:
right = ((other_uncert.array * other_uncert.unit).to(
other_uncert.parent_nddata.unit).value /
other_uncert.parent_nddata.data) * result_data
else:
right = (result_data * other_uncert.array /
other_uncert.parent_nddata.data)
if isinstance(correlation, np.ndarray) or correlation != 0:
corr = 2 * correlation * left * right
# This differs from multiplication because the correlation
# term needs to be subtracted
return np.sqrt(left**2 + right**2 - corr)
else:
return np.sqrt(left**2 + right**2)
|
4088547764692288bd0f788d383e49af7e88f113750aecb614a8d41157fd519e | # Licensed under a 3-clause BSD style license - see LICENSE.rst
from collections import OrderedDict
import numpy as np
from ..utils.misc import isiterable
__all__ = ['FlagCollection']
class FlagCollection(OrderedDict):
"""
The purpose of this class is to provide a dictionary for
containing arrays of flags for the `NDData` class. Flags should be
stored in Numpy arrays that have the same dimensions as the parent
data, so the `FlagCollection` class adds shape checking to an
ordered dictionary class.
The `FlagCollection` should be initialized like an
`~collections.OrderedDict`, but with the addition of a ``shape=``
keyword argument used to pass the NDData shape.
"""
def __init__(self, *args, **kwargs):
if 'shape' in kwargs:
self.shape = kwargs.pop('shape')
if not isiterable(self.shape):
raise ValueError("FlagCollection shape should be "
"an iterable object")
else:
raise Exception("FlagCollection should be initialized with "
"the shape of the data")
OrderedDict.__init__(self, *args, **kwargs)
def __setitem__(self, item, value, **kwargs):
if isinstance(value, np.ndarray):
if value.shape == self.shape:
OrderedDict.__setitem__(self, item, value, **kwargs)
else:
raise ValueError("flags array shape {0} does not match data "
"shape {1}".format(value.shape, self.shape))
else:
raise TypeError("flags should be given as a Numpy array")
|
c055a75e98e0a7124e60b85bc9dfce1598f4e344a582bd4dd42b4cca744b6d49 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
# This module implements the base NDData class.
import numpy as np
from copy import deepcopy
from .nddata_base import NDDataBase
from .nduncertainty import NDUncertainty, UnknownUncertainty
from .. import log
from ..units import Unit, Quantity
from ..utils.metadata import MetaData
__all__ = ['NDData']
_meta_doc = """`dict`-like : Additional meta information about the dataset."""
class NDData(NDDataBase):
"""
A container for `numpy.ndarray`-based datasets, using the
`~astropy.nddata.NDDataBase` interface.
The key distinction from raw `numpy.ndarray` is the presence of
additional metadata such as uncertainty, mask, unit, a coordinate system
and/or a dictionary containing further meta information. This class *only*
provides a container for *storing* such datasets. For further functionality
take a look at the ``See also`` section.
Parameters
-----------
data : `numpy.ndarray`-like or `NDData`-like
The dataset.
uncertainty : any type, optional
Uncertainty in the dataset.
Should have an attribute ``uncertainty_type`` that defines what kind of
uncertainty is stored, for example ``"std"`` for standard deviation or
``"var"`` for variance. A metaclass defining such an interface is
`NDUncertainty` - but isn't mandatory. If the uncertainty has no such
attribute the uncertainty is stored as `UnknownUncertainty`.
Defaults to ``None``.
mask : any type, optional
Mask for the dataset. Masks should follow the ``numpy`` convention that
**valid** data points are marked by ``False`` and **invalid** ones with
``True``.
Defaults to ``None``.
wcs : any type, optional
World coordinate system (WCS) for the dataset.
Default is ``None``.
meta : `dict`-like object, optional
Additional meta information about the dataset. If no meta is provided
an empty `collections.OrderedDict` is created.
Default is ``None``.
unit : `~astropy.units.Unit`-like or str, optional
Unit for the dataset. Strings that can be converted to a
`~astropy.units.Unit` are allowed.
Default is ``None``.
copy : `bool`, optional
Indicates whether to save the arguments as copy. ``True`` copies
every attribute before saving it while ``False`` tries to save every
parameter as reference.
Note however that it is not always possible to save the input as
reference.
Default is ``False``.
.. versionadded:: 1.2
Raises
------
TypeError
In case ``data`` or ``meta`` don't meet the restrictions.
Notes
-----
Each attribute can be accessed through the homonymous instance attribute:
``data`` in a `NDData` object can be accessed through the `data`
attribute::
>>> from astropy.nddata import NDData
>>> nd = NDData([1,2,3])
>>> nd.data
array([1, 2, 3])
Given a conflicting implicit and an explicit parameter during
initialization, for example the ``data`` is a `~astropy.units.Quantity` and
the unit parameter is not ``None``, then the implicit parameter is replaced
(without conversion) by the explicit one and a warning is issued::
>>> import numpy as np
>>> import astropy.units as u
>>> q = np.array([1,2,3,4]) * u.m
>>> nd2 = NDData(q, unit=u.cm)
INFO: overwriting Quantity's current unit with specified unit. [astropy.nddata.nddata]
>>> nd2.data # doctest: +FLOAT_CMP
array([1., 2., 3., 4.])
>>> nd2.unit
Unit("cm")
See also
--------
NDDataRef
NDDataArray
"""
# Instead of a custom property use the MetaData descriptor also used for
# Tables. It will check if the meta is dict-like or raise an exception.
meta = MetaData(doc=_meta_doc, copy=False)
def __init__(self, data, uncertainty=None, mask=None, wcs=None,
meta=None, unit=None, copy=False):
# Rather pointless since the NDDataBase does not implement any setting
# but before the NDDataBase did call the uncertainty
# setter. But if anyone wants to alter this behaviour again the call
# to the superclass NDDataBase should be in here.
super().__init__()
# Check if data is any type from which to collect some implicitly
# passed parameters.
if isinstance(data, NDData): # don't use self.__class__ (issue #4137)
# Of course we need to check the data because subclasses with other
# init-logic might be passed in here. We could skip these
# tests if we compared for self.__class__ but that has other
# drawbacks.
# Comparing if there is an explicit and an implicit unit parameter.
# If that is the case use the explicit one and issue a warning
# that there might be a conflict. In case there is no explicit
# unit just overwrite the unit parameter with the NDData.unit
# and proceed as if that one was given as parameter. Same for the
# other parameters.
if (unit is not None and data.unit is not None and
unit != data.unit):
log.info("overwriting NDData's current "
"unit with specified unit.")
elif data.unit is not None:
unit = data.unit
if uncertainty is not None and data.uncertainty is not None:
log.info("overwriting NDData's current "
"uncertainty with specified uncertainty.")
elif data.uncertainty is not None:
uncertainty = data.uncertainty
if mask is not None and data.mask is not None:
log.info("overwriting NDData's current "
"mask with specified mask.")
elif data.mask is not None:
mask = data.mask
if wcs is not None and data.wcs is not None:
log.info("overwriting NDData's current "
"wcs with specified wcs.")
elif data.wcs is not None:
wcs = data.wcs
if meta is not None and data.meta is not None:
log.info("overwriting NDData's current "
"meta with specified meta.")
elif data.meta is not None:
meta = data.meta
data = data.data
else:
if hasattr(data, 'mask') and hasattr(data, 'data'):
# Separating data and mask
if mask is not None:
log.info("overwriting Masked Objects's current "
"mask with specified mask.")
else:
mask = data.mask
# Just save the data for further processing, we could be given
# a masked Quantity or something else entirely. Better to check
# it first.
data = data.data
if isinstance(data, Quantity):
if unit is not None and unit != data.unit:
log.info("overwriting Quantity's current "
"unit with specified unit.")
else:
unit = data.unit
data = data.value
# Quick check on the parameters if they match the requirements.
if (not hasattr(data, 'shape') or not hasattr(data, '__getitem__') or
not hasattr(data, '__array__')):
# Data doesn't look like a numpy array, try converting it to
# one.
data = np.array(data, subok=True, copy=False)
# Another quick check to see if what we got looks like an array
# rather than an object (since numpy will convert a
# non-numerical/non-string inputs to an array of objects).
if data.dtype == 'O':
raise TypeError("could not convert data to numpy array.")
if unit is not None:
unit = Unit(unit)
if copy:
# Data might have been copied before but no way of validating
# without another variable.
data = deepcopy(data)
mask = deepcopy(mask)
wcs = deepcopy(wcs)
meta = deepcopy(meta)
uncertainty = deepcopy(uncertainty)
# Actually - copying the unit is unnecessary but better safe
# than sorry :-)
unit = deepcopy(unit)
# Store the attributes
self._data = data
self.mask = mask
self._wcs = wcs
self.meta = meta # TODO: Make this call the setter sometime
self._unit = unit
# Call the setter for uncertainty to further check the uncertainty
self.uncertainty = uncertainty
def __str__(self):
return str(self.data)
def __repr__(self):
prefix = self.__class__.__name__ + '('
body = np.array2string(self.data, separator=', ', prefix=prefix)
return ''.join([prefix, body, ')'])
@property
def data(self):
"""
`~numpy.ndarray`-like : The stored dataset.
"""
return self._data
@property
def mask(self):
"""
any type : Mask for the dataset, if any.
Masks should follow the ``numpy`` convention that valid data points are
marked by ``False`` and invalid ones with ``True``.
"""
return self._mask
@mask.setter
def mask(self, value):
self._mask = value
@property
def unit(self):
"""
`~astropy.units.Unit` : Unit for the dataset, if any.
"""
return self._unit
@property
def wcs(self):
"""
any type : A world coordinate system (WCS) for the dataset, if any.
"""
return self._wcs
@property
def uncertainty(self):
"""
any type : Uncertainty in the dataset, if any.
Should have an attribute ``uncertainty_type`` that defines what kind of
uncertainty is stored, such as ``'std'`` for standard deviation or
``'var'`` for variance. A metaclass defining such an interface is
`~astropy.nddata.NDUncertainty` but isn't mandatory.
"""
return self._uncertainty
@uncertainty.setter
def uncertainty(self, value):
if value is not None:
# There is one requirements on the uncertainty: That
# it has an attribute 'uncertainty_type'.
# If it does not match this requirement convert it to an unknown
# uncertainty.
if not hasattr(value, 'uncertainty_type'):
log.info('uncertainty should have attribute uncertainty_type.')
value = UnknownUncertainty(value, copy=False)
# If it is a subclass of NDUncertainty we must set the
# parent_nddata attribute. (#4152)
if isinstance(value, NDUncertainty):
# In case the uncertainty already has a parent create a new
# instance because we need to assume that we don't want to
# steal the uncertainty from another NDData object
if value._parent_nddata is not None:
value = value.__class__(value, copy=False)
# Then link it to this NDData instance (internally this needs
# to be saved as weakref but that's done by NDUncertainty
# setter).
value.parent_nddata = self
self._uncertainty = value
|
045b64842f3bb755954f51b9fdf1e64827c72e9ed6fd940fbbe84078cb092254 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
The `astropy.nddata` subpackage provides the `~astropy.nddata.NDData`
class and related tools to manage n-dimensional array-based data (e.g.
CCD images, IFU Data, grid-based simulation data, ...). This is more than
just `numpy.ndarray` objects, because it provides metadata that cannot
be easily provided by a single array.
"""
from .nddata import *
from .nddata_base import *
from .nddata_withmixins import *
from .nduncertainty import *
from .flag_collection import *
from .decorators import *
from .mixins.ndarithmetic import *
from .mixins.ndslicing import *
from .mixins.ndio import *
from .compat import *
from .utils import *
from .ccddata import *
from .. import config as _config
class Conf(_config.ConfigNamespace):
"""
Configuration parameters for `astropy.nddata`.
"""
warn_unsupported_correlated = _config.ConfigItem(
True,
'Whether to issue a warning if `~astropy.nddata.NDData` arithmetic '
'is performed with uncertainties and the uncertainties do not '
'support the propagation of correlated uncertainties.'
)
warn_setting_unit_directly = _config.ConfigItem(
True,
'Whether to issue a warning when the `~astropy.nddata.NDData` unit '
'attribute is changed from a non-``None`` value to another value '
'that data values/uncertainties are not scaled with the unit change.'
)
conf = Conf()
|
8aff5abd366abdcbb6dd88b2a5062dcbd460efb806db89a340601ea89f70bdf7 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""This module implements the base CCDData class."""
import numpy as np
from .compat import NDDataArray
from .nduncertainty import StdDevUncertainty, NDUncertainty
from ..io import fits, registry
from .. import units as u
from .. import log
from ..wcs import WCS
from ..utils.decorators import sharedmethod
__all__ = ['CCDData', 'fits_ccddata_reader', 'fits_ccddata_writer']
# Global value which can turn on/off the unit requirements when creating a
# CCDData. Should be used with care because several functions actually break
# if the unit is None!
_config_ccd_requires_unit = True
def _arithmetic(op):
"""Decorator factory which temporarly disables the need for a unit when
creating a new CCDData instance. The final result must have a unit.
Parameters
----------
op : function
The function to apply. Supported are:
- ``np.add``
- ``np.subtract``
- ``np.multiply``
- ``np.true_divide``
Notes
-----
Should only be used on CCDData ``add``, ``subtract``, ``divide`` or
``multiply`` because only these methods from NDArithmeticMixin are
overwritten.
"""
def decorator(func):
def inner(self, operand, operand2=None, **kwargs):
global _config_ccd_requires_unit
_config_ccd_requires_unit = False
result = self._prepare_then_do_arithmetic(op, operand,
operand2, **kwargs)
# Wrap it again as CCDData so it checks the final unit.
_config_ccd_requires_unit = True
return result.__class__(result)
inner.__doc__ = ("See `astropy.nddata.NDArithmeticMixin.{}`."
"".format(func.__name__))
return sharedmethod(inner)
return decorator
class CCDData(NDDataArray):
"""A class describing basic CCD data.
The CCDData class is based on the NDData object and includes a data array,
uncertainty frame, mask frame, flag frame, meta data, units, and WCS
information for a single CCD image.
Parameters
-----------
data : `~astropy.nddata.CCDData`-like or `numpy.ndarray`-like
The actual data contained in this `~astropy.nddata.CCDData` object.
Note that the data will always be saved by *reference*, so you should
make a copy of the ``data`` before passing it in if that's the desired
behavior.
uncertainty : `~astropy.nddata.StdDevUncertainty`, `numpy.ndarray` or \
None, optional
Uncertainties on the data.
Default is ``None``.
mask : `numpy.ndarray` or None, optional
Mask for the data, given as a boolean Numpy array with a shape
matching that of the data. The values must be `False` where
the data is *valid* and `True` when it is not (like Numpy
masked arrays). If ``data`` is a numpy masked array, providing
``mask`` here will causes the mask from the masked array to be
ignored.
Default is ``None``.
flags : `numpy.ndarray` or `~astropy.nddata.FlagCollection` or None, \
optional
Flags giving information about each pixel. These can be specified
either as a Numpy array of any type with a shape matching that of the
data, or as a `~astropy.nddata.FlagCollection` instance which has a
shape matching that of the data.
Default is ``None``.
wcs : `~astropy.wcs.WCS` or None, optional
WCS-object containing the world coordinate system for the data.
Default is ``None``.
meta : dict-like object or None, optional
Metadata for this object. "Metadata" here means all information that
is included with this object but not part of any other attribute
of this particular object, e.g. creation date, unique identifier,
simulation parameters, exposure time, telescope name, etc.
unit : `~astropy.units.Unit` or str, optional
The units of the data.
Default is ``None``.
.. warning::
If the unit is ``None`` or not otherwise specified it will raise a
``ValueError``
Raises
------
ValueError
If the ``uncertainty`` or ``mask`` inputs cannot be broadcast (e.g.,
match shape) onto ``data``.
Methods
-------
read(\\*args, \\**kwargs)
``Classmethod`` to create an CCDData instance based on a ``FITS`` file.
This method uses :func:`fits_ccddata_reader` with the provided
parameters.
write(\\*args, \\**kwargs)
Writes the contents of the CCDData instance into a new ``FITS`` file.
This method uses :func:`fits_ccddata_writer` with the provided
parameters.
Notes
-----
`~astropy.nddata.CCDData` objects can be easily converted to a regular
Numpy array using `numpy.asarray`.
For example::
>>> from astropy.nddata import CCDData
>>> import numpy as np
>>> x = CCDData([1,2,3], unit='adu')
>>> np.asarray(x)
array([1, 2, 3])
This is useful, for example, when plotting a 2D image using
matplotlib.
>>> from astropy.nddata import CCDData
>>> from matplotlib import pyplot as plt # doctest: +SKIP
>>> x = CCDData([[1,2,3], [4,5,6]], unit='adu')
>>> plt.imshow(x) # doctest: +SKIP
"""
def __init__(self, *args, **kwd):
if 'meta' not in kwd:
kwd['meta'] = kwd.pop('header', None)
if 'header' in kwd:
raise ValueError("can't have both header and meta.")
super().__init__(*args, **kwd)
# Check if a unit is set. This can be temporarly disabled by the
# _CCDDataUnit contextmanager.
if _config_ccd_requires_unit and self.unit is None:
raise ValueError("a unit for CCDData must be specified.")
@property
def data(self):
return self._data
@data.setter
def data(self, value):
self._data = value
@property
def wcs(self):
return self._wcs
@wcs.setter
def wcs(self, value):
self._wcs = value
@property
def unit(self):
return self._unit
@unit.setter
def unit(self, value):
self._unit = u.Unit(value)
@property
def header(self):
return self._meta
@header.setter
def header(self, value):
self.meta = value
@property
def uncertainty(self):
return self._uncertainty
@uncertainty.setter
def uncertainty(self, value):
if value is not None:
if isinstance(value, NDUncertainty):
if getattr(value, '_parent_nddata', None) is not None:
value = value.__class__(value, copy=False)
self._uncertainty = value
elif isinstance(value, np.ndarray):
if value.shape != self.shape:
raise ValueError("uncertainty must have same shape as "
"data.")
self._uncertainty = StdDevUncertainty(value)
log.info("array provided for uncertainty; assuming it is a "
"StdDevUncertainty.")
else:
raise TypeError("uncertainty must be an instance of a "
"NDUncertainty object or a numpy array.")
self._uncertainty.parent_nddata = self
else:
self._uncertainty = value
def to_hdu(self, hdu_mask='MASK', hdu_uncertainty='UNCERT',
hdu_flags=None, wcs_relax=True):
"""Creates an HDUList object from a CCDData object.
Parameters
----------
hdu_mask, hdu_uncertainty, hdu_flags : str or None, optional
If it is a string append this attribute to the HDUList as
`~astropy.io.fits.ImageHDU` with the string as extension name.
Flags are not supported at this time. If ``None`` this attribute
is not appended.
Default is ``'MASK'`` for mask, ``'UNCERT'`` for uncertainty and
``None`` for flags.
wcs_relax : bool
Value of the ``relax`` parameter to use in converting the WCS to a
FITS header using `~astropy.wcs.WCS.to_header`. The common
``CTYPE`` ``RA---TAN-SIP`` and ``DEC--TAN-SIP`` requires
``relax=True`` for the ``-SIP`` part of the ``CTYPE`` to be
preserved.
Raises
-------
ValueError
- If ``self.mask`` is set but not a `numpy.ndarray`.
- If ``self.uncertainty`` is set but not a
`~astropy.nddata.StdDevUncertainty`.
- If ``self.uncertainty`` is set but has another unit then
``self.data``.
NotImplementedError
Saving flags is not supported.
Returns
-------
hdulist : `~astropy.io.fits.HDUList`
"""
if isinstance(self.header, fits.Header):
# Copy here so that we can modify the HDU header by adding WCS
# information without changing the header of the CCDData object.
header = self.header.copy()
else:
# Because _insert_in_metadata_fits_safe is written as a method
# we need to create a dummy CCDData instance to hold the FITS
# header we are constructing. This probably indicates that
# _insert_in_metadata_fits_safe should be rewritten in a more
# sensible way...
dummy_ccd = CCDData([1], meta=fits.Header(), unit="adu")
for k, v in self.header.items():
dummy_ccd._insert_in_metadata_fits_safe(k, v)
header = dummy_ccd.header
if self.unit is not u.dimensionless_unscaled:
header['bunit'] = self.unit.to_string()
if self.wcs:
# Simply extending the FITS header with the WCS can lead to
# duplicates of the WCS keywords; iterating over the WCS
# header should be safer.
#
# Turns out if I had read the io.fits.Header.extend docs more
# carefully, I would have realized that the keywords exist to
# avoid duplicates and preserve, as much as possible, the
# structure of the commentary cards.
#
# Note that until astropy/astropy#3967 is closed, the extend
# will fail if there are comment cards in the WCS header but
# not header.
wcs_header = self.wcs.to_header(relax=wcs_relax)
header.extend(wcs_header, useblanks=False, update=True)
hdus = [fits.PrimaryHDU(self.data, header)]
if hdu_mask and self.mask is not None:
# Always assuming that the mask is a np.ndarray (check that it has
# a 'shape').
if not hasattr(self.mask, 'shape'):
raise ValueError('only a numpy.ndarray mask can be saved.')
# Convert boolean mask to uint since io.fits cannot handle bool.
hduMask = fits.ImageHDU(self.mask.astype(np.uint8), name=hdu_mask)
hdus.append(hduMask)
if hdu_uncertainty and self.uncertainty is not None:
# We need to save some kind of information which uncertainty was
# used so that loading the HDUList can infer the uncertainty type.
# No idea how this can be done so only allow StdDevUncertainty.
if self.uncertainty.__class__.__name__ != 'StdDevUncertainty':
raise ValueError('only StdDevUncertainty can be saved.')
# Assuming uncertainty is an StdDevUncertainty save just the array
# this might be problematic if the Uncertainty has a unit differing
# from the data so abort for different units. This is important for
# astropy > 1.2
if (hasattr(self.uncertainty, 'unit') and
self.uncertainty.unit is not None and
self.uncertainty.unit != self.unit):
raise ValueError('saving uncertainties with a unit differing'
'from the data unit is not supported.')
hduUncert = fits.ImageHDU(self.uncertainty.array,
name=hdu_uncertainty)
hdus.append(hduUncert)
if hdu_flags and self.flags:
raise NotImplementedError('adding the flags to a HDU is not '
'supported at this time.')
hdulist = fits.HDUList(hdus)
return hdulist
def copy(self):
"""
Return a copy of the CCDData object.
"""
return self.__class__(self, copy=True)
add = _arithmetic(np.add)(NDDataArray.add)
subtract = _arithmetic(np.subtract)(NDDataArray.subtract)
multiply = _arithmetic(np.multiply)(NDDataArray.multiply)
divide = _arithmetic(np.true_divide)(NDDataArray.divide)
def _insert_in_metadata_fits_safe(self, key, value):
"""
Insert key/value pair into metadata in a way that FITS can serialize.
Parameters
----------
key : str
Key to be inserted in dictionary.
value : str or None
Value to be inserted.
Notes
-----
This addresses a shortcoming of the FITS standard. There are length
restrictions on both the ``key`` (8 characters) and ``value`` (72
characters) in the FITS standard. There is a convention for handling
long keywords and a convention for handling long values, but the
two conventions cannot be used at the same time.
This addresses that case by checking the length of the ``key`` and
``value`` and, if necessary, shortening the key.
"""
if len(key) > 8 and len(value) > 72:
short_name = key[:8]
self.meta['HIERARCH {0}'.format(key.upper())] = (
short_name, "Shortened name for {}".format(key))
self.meta[short_name] = value
else:
self.meta[key] = value
# This needs to be importable by the tests...
_KEEP_THESE_KEYWORDS_IN_HEADER = [
'JD-OBS',
'MJD-OBS',
'DATE-OBS'
]
def _generate_wcs_and_update_header(hdr):
"""
Generate a WCS object from a header and remove the WCS-specific
keywords from the header.
Parameters
----------
hdr : astropy.io.fits.header or other dict-like
Returns
-------
new_header, wcs
"""
# Try constructing a WCS object.
try:
wcs = WCS(hdr)
except Exception as exc:
# Normally WCS only raises Warnings and doesn't fail but in rare
# cases (malformed header) it could fail...
log.info('An exception happened while extracting WCS informations from '
'the Header.\n{}: {}'.format(type(exc).__name__, str(exc)))
return hdr, None
# Test for success by checking to see if the wcs ctype has a non-empty
# value, return None for wcs if ctype is empty.
if not wcs.wcs.ctype[0]:
return (hdr, None)
new_hdr = hdr.copy()
# If the keywords below are in the header they are also added to WCS.
# It seems like they should *not* be removed from the header, though.
wcs_header = wcs.to_header(relax=True)
for k in wcs_header:
if k not in _KEEP_THESE_KEYWORDS_IN_HEADER:
new_hdr.remove(k, ignore_missing=True)
return (new_hdr, wcs)
def fits_ccddata_reader(filename, hdu=0, unit=None, hdu_uncertainty='UNCERT',
hdu_mask='MASK', hdu_flags=None, **kwd):
"""
Generate a CCDData object from a FITS file.
Parameters
----------
filename : str
Name of fits file.
hdu : int, optional
FITS extension from which CCDData should be initialized. If zero and
and no data in the primary extension, it will search for the first
extension with data. The header will be added to the primary header.
Default is ``0``.
unit : `~astropy.units.Unit`, optional
Units of the image data. If this argument is provided and there is a
unit for the image in the FITS header (the keyword ``BUNIT`` is used
as the unit, if present), this argument is used for the unit.
Default is ``None``.
hdu_uncertainty : str or None, optional
FITS extension from which the uncertainty should be initialized. If the
extension does not exist the uncertainty of the CCDData is ``None``.
Default is ``'UNCERT'``.
hdu_mask : str or None, optional
FITS extension from which the mask should be initialized. If the
extension does not exist the mask of the CCDData is ``None``.
Default is ``'MASK'``.
hdu_flags : str or None, optional
Currently not implemented.
Default is ``None``.
kwd :
Any additional keyword parameters are passed through to the FITS reader
in :mod:`astropy.io.fits`; see Notes for additional discussion.
Notes
-----
FITS files that contained scaled data (e.g. unsigned integer images) will
be scaled and the keywords used to manage scaled data in
:mod:`astropy.io.fits` are disabled.
"""
unsupport_open_keywords = {
'do_not_scale_image_data': 'Image data must be scaled.',
'scale_back': 'Scale information is not preserved.'
}
for key, msg in unsupport_open_keywords.items():
if key in kwd:
prefix = 'unsupported keyword: {0}.'.format(key)
raise TypeError(' '.join([prefix, msg]))
with fits.open(filename, **kwd) as hdus:
hdr = hdus[hdu].header
if hdu_uncertainty is not None and hdu_uncertainty in hdus:
uncertainty = StdDevUncertainty(hdus[hdu_uncertainty].data)
else:
uncertainty = None
if hdu_mask is not None and hdu_mask in hdus:
# Mask is saved as uint but we want it to be boolean.
mask = hdus[hdu_mask].data.astype(np.bool_)
else:
mask = None
if hdu_flags is not None and hdu_flags in hdus:
raise NotImplementedError('loading flags is currently not '
'supported.')
# search for the first instance with data if
# the primary header is empty.
if hdu == 0 and hdus[hdu].data is None:
for i in range(len(hdus)):
if hdus.fileinfo(i)['datSpan'] > 0:
hdu = i
comb_hdr = hdus[hdu].header.copy()
# Add header values from the primary header that aren't
# present in the extension header.
comb_hdr.extend(hdr, unique=True)
hdr = comb_hdr
log.info("first HDU with data is extension "
"{0}.".format(hdu))
break
if 'bunit' in hdr:
fits_unit_string = hdr['bunit']
# patch to handle FITS files using ADU for the unit instead of the
# standard version of 'adu'
if fits_unit_string.strip().lower() == 'adu':
fits_unit_string = fits_unit_string.lower()
else:
fits_unit_string = None
if unit is not None and fits_unit_string:
log.info("using the unit {0} passed to the FITS reader instead of "
"the unit {1} in the FITS file.".format(unit,
fits_unit_string))
use_unit = unit or fits_unit_string
hdr, wcs = _generate_wcs_and_update_header(hdr)
ccd_data = CCDData(hdus[hdu].data, meta=hdr, unit=use_unit,
mask=mask, uncertainty=uncertainty, wcs=wcs)
return ccd_data
def fits_ccddata_writer(ccd_data, filename, hdu_mask='MASK',
hdu_uncertainty='UNCERT', hdu_flags=None, **kwd):
"""
Write CCDData object to FITS file.
Parameters
----------
filename : str
Name of file.
hdu_mask, hdu_uncertainty, hdu_flags : str or None, optional
If it is a string append this attribute to the HDUList as
`~astropy.io.fits.ImageHDU` with the string as extension name.
Flags are not supported at this time. If ``None`` this attribute
is not appended.
Default is ``'MASK'`` for mask, ``'UNCERT'`` for uncertainty and
``None`` for flags.
kwd :
All additional keywords are passed to :py:mod:`astropy.io.fits`
Raises
-------
ValueError
- If ``self.mask`` is set but not a `numpy.ndarray`.
- If ``self.uncertainty`` is set but not a
`~astropy.nddata.StdDevUncertainty`.
- If ``self.uncertainty`` is set but has another unit then
``self.data``.
NotImplementedError
Saving flags is not supported.
"""
hdu = ccd_data.to_hdu(hdu_mask=hdu_mask, hdu_uncertainty=hdu_uncertainty,
hdu_flags=hdu_flags)
hdu.writeto(filename, **kwd)
with registry.delay_doc_updates(CCDData):
registry.register_reader('fits', CCDData, fits_ccddata_reader)
registry.register_writer('fits', CCDData, fits_ccddata_writer)
registry.register_identifier('fits', CCDData, fits.connect.is_fits)
try:
CCDData.read.__doc__ = fits_ccddata_reader.__doc__
except AttributeError:
CCDData.read.__func__.__doc__ = fits_ccddata_reader.__doc__
try:
CCDData.write.__doc__ = fits_ccddata_writer.__doc__
except AttributeError:
CCDData.write.__func__.__doc__ = fits_ccddata_writer.__doc__
|
0a8478a941809b2acb423274acc96468cb955cf6f84ec126bf807ba662640c55 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
def get_package_data():
return {'astropy.nddata.tests': ['data/*.fits']}
|
5a08fc56dbac243bc68d3740f377ee68361a543de89919cc836c7e958cca3e51 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module includes helper functions for array operations.
"""
from copy import deepcopy
import numpy as np
from .decorators import support_nddata
from .. import units as u
from ..coordinates import SkyCoord
from ..utils import lazyproperty
from ..wcs.utils import skycoord_to_pixel, proj_plane_pixel_scales
__all__ = ['extract_array', 'add_array', 'subpixel_indices',
'overlap_slices', 'block_reduce', 'block_replicate',
'NoOverlapError', 'PartialOverlapError', 'Cutout2D']
class NoOverlapError(ValueError):
'''Raised when determining the overlap of non-overlapping arrays.'''
pass
class PartialOverlapError(ValueError):
'''Raised when arrays only partially overlap.'''
pass
def _round(a):
'''Always round up.
``np.round`` cannot be used here, because it rounds .5 to the nearest
even number.
'''
return int(np.floor(a + 0.5))
def _offset(a):
'''Offset by 0.5 for an even array.
For an array with an odd number of elements, the center is
symmetric, e.g. for 3 elements, it's center +/-1 elements, but for
four elements it's center -2 / +1
This function introduces that offset.
'''
if np.mod(a, 2) == 0:
return -0.5
else:
return 0.
def overlap_slices(large_array_shape, small_array_shape, position,
mode='partial'):
"""
Get slices for the overlapping part of a small and a large array.
Given a certain position of the center of the small array, with
respect to the large array, tuples of slices are returned which can be
used to extract, add or subtract the small array at the given
position. This function takes care of the correct behavior at the
boundaries, where the small array is cut of appropriately.
Integer positions are at the pixel centers.
Parameters
----------
large_array_shape : tuple or int
The shape of the large array (for 1D arrays, this can be an
`int`).
small_array_shape : tuple or int
The shape of the small array (for 1D arrays, this can be an
`int`). See the ``mode`` keyword for additional details.
position : tuple of numbers or number
The position of the small array's center with respect to the
large array. The pixel coordinates should be in the same order
as the array shape. Integer positions are at the pixel centers.
For any axis where ``small_array_shape`` is even, the position
is rounded up, e.g. extracting two elements with a center of
``1`` will define the extracted region as ``[0, 1]``.
mode : {'partial', 'trim', 'strict'}, optional
In ``'partial'`` mode, a partial overlap of the small and the
large array is sufficient. The ``'trim'`` mode is similar to
the ``'partial'`` mode, but ``slices_small`` will be adjusted to
return only the overlapping elements. In the ``'strict'`` mode,
the small array has to be fully contained in the large array,
otherwise an `~astropy.nddata.utils.PartialOverlapError` is
raised. In all modes, non-overlapping arrays will raise a
`~astropy.nddata.utils.NoOverlapError`.
Returns
-------
slices_large : tuple of slices
A tuple of slice objects for each axis of the large array, such
that ``large_array[slices_large]`` extracts the region of the
large array that overlaps with the small array.
slices_small : slice
A tuple of slice objects for each axis of the small array, such
that ``small_array[slices_small]`` extracts the region that is
inside the large array.
"""
if mode not in ['partial', 'trim', 'strict']:
raise ValueError('Mode can be only "partial", "trim", or "strict".')
if np.isscalar(small_array_shape):
small_array_shape = (small_array_shape, )
if np.isscalar(large_array_shape):
large_array_shape = (large_array_shape, )
if np.isscalar(position):
position = (position, )
if len(small_array_shape) != len(large_array_shape):
raise ValueError('"large_array_shape" and "small_array_shape" must '
'have the same number of dimensions.')
if len(small_array_shape) != len(position):
raise ValueError('"position" must have the same number of dimensions '
'as "small_array_shape".')
# Get edge coordinates
edges_min = [_round(pos + 0.5 - small_shape / 2. + _offset(small_shape))
for (pos, small_shape) in zip(position, small_array_shape)]
edges_max = [_round(pos + 0.5 + small_shape / 2. + _offset(small_shape))
for (pos, small_shape) in zip(position, small_array_shape)]
for e_max in edges_max:
if e_max <= 0:
raise NoOverlapError('Arrays do not overlap.')
for e_min, large_shape in zip(edges_min, large_array_shape):
if e_min >= large_shape:
raise NoOverlapError('Arrays do not overlap.')
if mode == 'strict':
for e_min in edges_min:
if e_min < 0:
raise PartialOverlapError('Arrays overlap only partially.')
for e_max, large_shape in zip(edges_max, large_array_shape):
if e_max >= large_shape:
raise PartialOverlapError('Arrays overlap only partially.')
# Set up slices
slices_large = tuple(slice(max(0, edge_min), min(large_shape, edge_max))
for (edge_min, edge_max, large_shape) in
zip(edges_min, edges_max, large_array_shape))
if mode == 'trim':
slices_small = tuple(slice(0, slc.stop - slc.start)
for slc in slices_large)
else:
slices_small = tuple(slice(max(0, -edge_min),
min(large_shape - edge_min,
edge_max - edge_min))
for (edge_min, edge_max, large_shape) in
zip(edges_min, edges_max, large_array_shape))
return slices_large, slices_small
def extract_array(array_large, shape, position, mode='partial',
fill_value=np.nan, return_position=False):
"""
Extract a smaller array of the given shape and position from a
larger array.
Parameters
----------
array_large : `~numpy.ndarray`
The array from which to extract the small array.
shape : tuple or int
The shape of the extracted array (for 1D arrays, this can be an
`int`). See the ``mode`` keyword for additional details.
position : tuple of numbers or number
The position of the small array's center with respect to the
large array. The pixel coordinates should be in the same order
as the array shape. Integer positions are at the pixel centers
(for 1D arrays, this can be a number).
mode : {'partial', 'trim', 'strict'}, optional
The mode used for extracting the small array. For the
``'partial'`` and ``'trim'`` modes, a partial overlap of the
small array and the large array is sufficient. For the
``'strict'`` mode, the small array has to be fully contained
within the large array, otherwise an
`~astropy.nddata.utils.PartialOverlapError` is raised. In all
modes, non-overlapping arrays will raise a
`~astropy.nddata.utils.NoOverlapError`. In ``'partial'`` mode,
positions in the small array that do not overlap with the large
array will be filled with ``fill_value``. In ``'trim'`` mode
only the overlapping elements are returned, thus the resulting
small array may be smaller than the requested ``shape``.
fill_value : number, optional
If ``mode='partial'``, the value to fill pixels in the extracted
small array that do not overlap with the input ``array_large``.
``fill_value`` must have the same ``dtype`` as the
``array_large`` array.
return_position : boolean, optional
If `True`, return the coordinates of ``position`` in the
coordinate system of the returned array.
Returns
-------
array_small : `~numpy.ndarray`
The extracted array.
new_position : tuple
If ``return_position`` is true, this tuple will contain the
coordinates of the input ``position`` in the coordinate system
of ``array_small``. Note that for partially overlapping arrays,
``new_position`` might actually be outside of the
``array_small``; ``array_small[new_position]`` might give wrong
results if any element in ``new_position`` is negative.
Examples
--------
We consider a large array with the shape 11x10, from which we extract
a small array of shape 3x5:
>>> import numpy as np
>>> from astropy.nddata.utils import extract_array
>>> large_array = np.arange(110).reshape((11, 10))
>>> extract_array(large_array, (3, 5), (7, 7))
array([[65, 66, 67, 68, 69],
[75, 76, 77, 78, 79],
[85, 86, 87, 88, 89]])
"""
if np.isscalar(shape):
shape = (shape, )
if np.isscalar(position):
position = (position, )
if mode not in ['partial', 'trim', 'strict']:
raise ValueError("Valid modes are 'partial', 'trim', and 'strict'.")
large_slices, small_slices = overlap_slices(array_large.shape,
shape, position, mode=mode)
extracted_array = array_large[large_slices]
if return_position:
new_position = [i - s.start for i, s in zip(position, large_slices)]
# Extracting on the edges is presumably a rare case, so treat special here
if (extracted_array.shape != shape) and (mode == 'partial'):
extracted_array = np.zeros(shape, dtype=array_large.dtype)
extracted_array[:] = fill_value
extracted_array[small_slices] = array_large[large_slices]
if return_position:
new_position = [i + s.start for i, s in zip(new_position,
small_slices)]
if return_position:
return extracted_array, tuple(new_position)
else:
return extracted_array
def add_array(array_large, array_small, position):
"""
Add a smaller array at a given position in a larger array.
Parameters
----------
array_large : `~numpy.ndarray`
Large array.
array_small : `~numpy.ndarray`
Small array to add.
position : tuple
Position of the small array's center, with respect to the large array.
Coordinates should be in the same order as the array shape.
Returns
-------
new_array : `~numpy.ndarray`
The new array formed from the sum of ``array_large`` and
``array_small``.
Notes
-----
The addition is done in-place.
Examples
--------
We consider a large array of zeros with the shape 5x5 and a small
array of ones with a shape of 3x3:
>>> import numpy as np
>>> from astropy.nddata.utils import add_array
>>> large_array = np.zeros((5, 5))
>>> small_array = np.ones((3, 3))
>>> add_array(large_array, small_array, (1, 2)) # doctest: +FLOAT_CMP
array([[0., 1., 1., 1., 0.],
[0., 1., 1., 1., 0.],
[0., 1., 1., 1., 0.],
[0., 0., 0., 0., 0.],
[0., 0., 0., 0., 0.]])
"""
# Check if large array is really larger
if all(large_shape > small_shape for (large_shape, small_shape)
in zip(array_large.shape, array_small.shape)):
large_slices, small_slices = overlap_slices(array_large.shape,
array_small.shape, position)
array_large[large_slices] += array_small[small_slices]
return array_large
else:
raise ValueError("Can't add array. Small array too large.")
def subpixel_indices(position, subsampling):
"""
Convert decimal points to indices, given a subsampling factor.
This discards the integer part of the position and uses only the decimal
place, and converts this to a subpixel position depending on the
subsampling specified. The center of a pixel corresponds to an integer
position.
Parameters
----------
position : `~numpy.ndarray` or array-like
Positions in pixels.
subsampling : int
Subsampling factor per pixel.
Returns
-------
indices : `~numpy.ndarray`
The integer subpixel indices corresponding to the input positions.
Examples
--------
If no subsampling is used, then the subpixel indices returned are always 0:
>>> from astropy.nddata.utils import subpixel_indices
>>> subpixel_indices([1.2, 3.4, 5.6], 1) # doctest: +FLOAT_CMP
array([0., 0., 0.])
If instead we use a subsampling of 2, we see that for the two first values
(1.1 and 3.4) the subpixel position is 1, while for 5.6 it is 0. This is
because the values of 1, 3, and 6 lie in the center of pixels, and 1.1 and
3.4 lie in the left part of the pixels and 5.6 lies in the right part.
>>> subpixel_indices([1.2, 3.4, 5.5], 2) # doctest: +FLOAT_CMP
array([1., 1., 0.])
"""
# Get decimal points
fractions = np.modf(np.asanyarray(position) + 0.5)[0]
return np.floor(fractions * subsampling)
@support_nddata
def block_reduce(data, block_size, func=np.sum):
"""
Downsample a data array by applying a function to local blocks.
If ``data`` is not perfectly divisible by ``block_size`` along a
given axis then the data will be trimmed (from the end) along that
axis.
Parameters
----------
data : array_like
The data to be resampled.
block_size : int or array_like (int)
The integer block size along each axis. If ``block_size`` is a
scalar and ``data`` has more than one dimension, then
``block_size`` will be used for for every axis.
func : callable, optional
The method to use to downsample the data. Must be a callable
that takes in a `~numpy.ndarray` along with an ``axis`` keyword,
which defines the axis along which the function is applied. The
default is `~numpy.sum`, which provides block summation (and
conserves the data sum).
Returns
-------
output : array-like
The resampled data.
Examples
--------
>>> import numpy as np
>>> from astropy.nddata.utils import block_reduce
>>> data = np.arange(16).reshape(4, 4)
>>> block_reduce(data, 2) # doctest: +SKIP
array([[10, 18],
[42, 50]])
>>> block_reduce(data, 2, func=np.mean) # doctest: +SKIP
array([[ 2.5, 4.5],
[ 10.5, 12.5]])
"""
from skimage.measure import block_reduce
data = np.asanyarray(data)
block_size = np.atleast_1d(block_size)
if data.ndim > 1 and len(block_size) == 1:
block_size = np.repeat(block_size, data.ndim)
if len(block_size) != data.ndim:
raise ValueError('`block_size` must be a scalar or have the same '
'length as `data.shape`')
block_size = np.array([int(i) for i in block_size])
size_resampled = np.array(data.shape) // block_size
size_init = size_resampled * block_size
# trim data if necessary
for i in range(data.ndim):
if data.shape[i] != size_init[i]:
data = data.swapaxes(0, i)
data = data[:size_init[i]]
data = data.swapaxes(0, i)
return block_reduce(data, tuple(block_size), func=func)
@support_nddata
def block_replicate(data, block_size, conserve_sum=True):
"""
Upsample a data array by block replication.
Parameters
----------
data : array_like
The data to be block replicated.
block_size : int or array_like (int)
The integer block size along each axis. If ``block_size`` is a
scalar and ``data`` has more than one dimension, then
``block_size`` will be used for for every axis.
conserve_sum : bool, optional
If `True` (the default) then the sum of the output
block-replicated data will equal the sum of the input ``data``.
Returns
-------
output : array_like
The block-replicated data.
Examples
--------
>>> import numpy as np
>>> from astropy.nddata.utils import block_replicate
>>> data = np.array([[0., 1.], [2., 3.]])
>>> block_replicate(data, 2) # doctest: +FLOAT_CMP
array([[0. , 0. , 0.25, 0.25],
[0. , 0. , 0.25, 0.25],
[0.5 , 0.5 , 0.75, 0.75],
[0.5 , 0.5 , 0.75, 0.75]])
>>> block_replicate(data, 2, conserve_sum=False) # doctest: +FLOAT_CMP
array([[0., 0., 1., 1.],
[0., 0., 1., 1.],
[2., 2., 3., 3.],
[2., 2., 3., 3.]])
"""
data = np.asanyarray(data)
block_size = np.atleast_1d(block_size)
if data.ndim > 1 and len(block_size) == 1:
block_size = np.repeat(block_size, data.ndim)
if len(block_size) != data.ndim:
raise ValueError('`block_size` must be a scalar or have the same '
'length as `data.shape`')
for i in range(data.ndim):
data = np.repeat(data, block_size[i], axis=i)
if conserve_sum:
data = data / float(np.prod(block_size))
return data
class Cutout2D:
"""
Create a cutout object from a 2D array.
The returned object will contain a 2D cutout array. If
``copy=False`` (default), the cutout array is a view into the
original ``data`` array, otherwise the cutout array will contain a
copy of the original data.
If a `~astropy.wcs.WCS` object is input, then the returned object
will also contain a copy of the original WCS, but updated for the
cutout array.
For example usage, see :ref:`cutout_images`.
.. warning::
The cutout WCS object does not currently handle cases where the
input WCS object contains distortion lookup tables described in
the `FITS WCS distortion paper
<http://www.atnf.csiro.au/people/mcalabre/WCS/dcs_20040422.pdf>`__.
Parameters
----------
data : `~numpy.ndarray`
The 2D data array from which to extract the cutout array.
position : tuple or `~astropy.coordinates.SkyCoord`
The position of the cutout array's center with respect to
the ``data`` array. The position can be specified either as
a ``(x, y)`` tuple of pixel coordinates or a
`~astropy.coordinates.SkyCoord`, in which case ``wcs`` is a
required input.
size : int, array-like, `~astropy.units.Quantity`
The size of the cutout array along each axis. If ``size``
is a scalar number or a scalar `~astropy.units.Quantity`,
then a square cutout of ``size`` will be created. If
``size`` has two elements, they should be in ``(ny, nx)``
order. Scalar numbers in ``size`` are assumed to be in
units of pixels. ``size`` can also be a
`~astropy.units.Quantity` object or contain
`~astropy.units.Quantity` objects. Such
`~astropy.units.Quantity` objects must be in pixel or
angular units. For all cases, ``size`` will be converted to
an integer number of pixels, rounding the the nearest
integer. See the ``mode`` keyword for additional details on
the final cutout size.
.. note::
If ``size`` is in angular units, the cutout size is
converted to pixels using the pixel scales along each
axis of the image at the ``CRPIX`` location. Projection
and other non-linear distortions are not taken into
account.
wcs : `~astropy.wcs.WCS`, optional
A WCS object associated with the input ``data`` array. If
``wcs`` is not `None`, then the returned cutout object will
contain a copy of the updated WCS for the cutout data array.
mode : {'trim', 'partial', 'strict'}, optional
The mode used for creating the cutout data array. For the
``'partial'`` and ``'trim'`` modes, a partial overlap of the
cutout array and the input ``data`` array is sufficient.
For the ``'strict'`` mode, the cutout array has to be fully
contained within the ``data`` array, otherwise an
`~astropy.nddata.utils.PartialOverlapError` is raised. In
all modes, non-overlapping arrays will raise a
`~astropy.nddata.utils.NoOverlapError`. In ``'partial'``
mode, positions in the cutout array that do not overlap with
the ``data`` array will be filled with ``fill_value``. In
``'trim'`` mode only the overlapping elements are returned,
thus the resulting cutout array may be smaller than the
requested ``shape``.
fill_value : number, optional
If ``mode='partial'``, the value to fill pixels in the
cutout array that do not overlap with the input ``data``.
``fill_value`` must have the same ``dtype`` as the input
``data`` array.
copy : bool, optional
If `False` (default), then the cutout data will be a view
into the original ``data`` array. If `True`, then the
cutout data will hold a copy of the original ``data`` array.
Attributes
----------
data : 2D `~numpy.ndarray`
The 2D cutout array.
shape : 2 tuple
The ``(ny, nx)`` shape of the cutout array.
shape_input : 2 tuple
The ``(ny, nx)`` shape of the input (original) array.
input_position_cutout : 2 tuple
The (unrounded) ``(x, y)`` position with respect to the cutout
array.
input_position_original : 2 tuple
The original (unrounded) ``(x, y)`` input position (with respect
to the original array).
slices_original : 2 tuple of slice objects
A tuple of slice objects for the minimal bounding box of the
cutout with respect to the original array. For
``mode='partial'``, the slices are for the valid (non-filled)
cutout values.
slices_cutout : 2 tuple of slice objects
A tuple of slice objects for the minimal bounding box of the
cutout with respect to the cutout array. For
``mode='partial'``, the slices are for the valid (non-filled)
cutout values.
xmin_original, ymin_original, xmax_original, ymax_original : float
The minimum and maximum ``x`` and ``y`` indices of the minimal
rectangular region of the cutout array with respect to the
original array. For ``mode='partial'``, the bounding box
indices are for the valid (non-filled) cutout values. These
values are the same as those in `bbox_original`.
xmin_cutout, ymin_cutout, xmax_cutout, ymax_cutout : float
The minimum and maximum ``x`` and ``y`` indices of the minimal
rectangular region of the cutout array with respect to the
cutout array. For ``mode='partial'``, the bounding box indices
are for the valid (non-filled) cutout values. These values are
the same as those in `bbox_cutout`.
wcs : `~astropy.wcs.WCS` or `None`
A WCS object associated with the cutout array if a ``wcs``
was input.
Examples
--------
>>> import numpy as np
>>> from astropy.nddata.utils import Cutout2D
>>> from astropy import units as u
>>> data = np.arange(20.).reshape(5, 4)
>>> cutout1 = Cutout2D(data, (2, 2), (3, 3))
>>> print(cutout1.data) # doctest: +FLOAT_CMP
[[ 5. 6. 7.]
[ 9. 10. 11.]
[13. 14. 15.]]
>>> print(cutout1.center_original)
(2.0, 2.0)
>>> print(cutout1.center_cutout)
(1.0, 1.0)
>>> print(cutout1.origin_original)
(1, 1)
>>> cutout2 = Cutout2D(data, (2, 2), 3)
>>> print(cutout2.data) # doctest: +FLOAT_CMP
[[ 5. 6. 7.]
[ 9. 10. 11.]
[13. 14. 15.]]
>>> size = u.Quantity([3, 3], u.pixel)
>>> cutout3 = Cutout2D(data, (0, 0), size)
>>> print(cutout3.data) # doctest: +FLOAT_CMP
[[0. 1.]
[4. 5.]]
>>> cutout4 = Cutout2D(data, (0, 0), (3 * u.pixel, 3))
>>> print(cutout4.data) # doctest: +FLOAT_CMP
[[0. 1.]
[4. 5.]]
>>> cutout5 = Cutout2D(data, (0, 0), (3, 3), mode='partial')
>>> print(cutout5.data) # doctest: +FLOAT_CMP
[[nan nan nan]
[nan 0. 1.]
[nan 4. 5.]]
"""
def __init__(self, data, position, size, wcs=None, mode='trim',
fill_value=np.nan, copy=False):
if isinstance(position, SkyCoord):
if wcs is None:
raise ValueError('wcs must be input if position is a '
'SkyCoord')
position = skycoord_to_pixel(position, wcs, mode='all') # (x, y)
if np.isscalar(size):
size = np.repeat(size, 2)
# special handling for a scalar Quantity
if isinstance(size, u.Quantity):
size = np.atleast_1d(size)
if len(size) == 1:
size = np.repeat(size, 2)
if len(size) > 2:
raise ValueError('size must have at most two elements')
shape = np.zeros(2).astype(int)
pixel_scales = None
# ``size`` can have a mixture of int and Quantity (and even units),
# so evaluate each axis separately
for axis, side in enumerate(size):
if not isinstance(side, u.Quantity):
shape[axis] = int(np.round(size[axis])) # pixels
else:
if side.unit == u.pixel:
shape[axis] = int(np.round(side.value))
elif side.unit.physical_type == 'angle':
if wcs is None:
raise ValueError('wcs must be input if any element '
'of size has angular units')
if pixel_scales is None:
pixel_scales = u.Quantity(
proj_plane_pixel_scales(wcs), wcs.wcs.cunit[axis])
shape[axis] = int(np.round(
(side / pixel_scales[axis]).decompose()))
else:
raise ValueError('shape can contain Quantities with only '
'pixel or angular units')
data = np.asanyarray(data)
# reverse position because extract_array and overlap_slices
# use (y, x), but keep the input position
pos_yx = position[::-1]
cutout_data, input_position_cutout = extract_array(
data, tuple(shape), pos_yx, mode=mode, fill_value=fill_value,
return_position=True)
if copy:
cutout_data = np.copy(cutout_data)
self.data = cutout_data
self.input_position_cutout = input_position_cutout[::-1] # (x, y)
slices_original, slices_cutout = overlap_slices(
data.shape, shape, pos_yx, mode=mode)
self.slices_original = slices_original
self.slices_cutout = slices_cutout
self.shape = self.data.shape
self.input_position_original = position
self.shape_input = shape
((self.ymin_original, self.ymax_original),
(self.xmin_original, self.xmax_original)) = self.bbox_original
((self.ymin_cutout, self.ymax_cutout),
(self.xmin_cutout, self.xmax_cutout)) = self.bbox_cutout
# the true origin pixel of the cutout array, including any
# filled cutout values
self._origin_original_true = (
self.origin_original[0] - self.slices_cutout[1].start,
self.origin_original[1] - self.slices_cutout[0].start)
if wcs is not None:
self.wcs = deepcopy(wcs)
self.wcs.wcs.crpix -= self._origin_original_true
else:
self.wcs = None
def to_original_position(self, cutout_position):
"""
Convert an ``(x, y)`` position in the cutout array to the original
``(x, y)`` position in the original large array.
Parameters
----------
cutout_position : tuple
The ``(x, y)`` pixel position in the cutout array.
Returns
-------
original_position : tuple
The corresponding ``(x, y)`` pixel position in the original
large array.
"""
return tuple(cutout_position[i] + self.origin_original[i]
for i in [0, 1])
def to_cutout_position(self, original_position):
"""
Convert an ``(x, y)`` position in the original large array to
the ``(x, y)`` position in the cutout array.
Parameters
----------
original_position : tuple
The ``(x, y)`` pixel position in the original large array.
Returns
-------
cutout_position : tuple
The corresponding ``(x, y)`` pixel position in the cutout
array.
"""
return tuple(original_position[i] - self.origin_original[i]
for i in [0, 1])
def plot_on_original(self, ax=None, fill=False, **kwargs):
"""
Plot the cutout region on a matplotlib Axes instance.
Parameters
----------
ax : `matplotlib.axes.Axes` instance, optional
If `None`, then the current `matplotlib.axes.Axes` instance
is used.
fill : bool, optional
Set whether to fill the cutout patch. The default is
`False`.
kwargs : optional
Any keyword arguments accepted by `matplotlib.patches.Patch`.
Returns
-------
ax : `matplotlib.axes.Axes` instance
The matplotlib Axes instance constructed in the method if
``ax=None``. Otherwise the output ``ax`` is the same as the
input ``ax``.
"""
import matplotlib.pyplot as plt
import matplotlib.patches as mpatches
kwargs['fill'] = fill
if ax is None:
ax = plt.gca()
height, width = self.shape
hw, hh = width / 2., height / 2.
pos_xy = self.position_original - np.array([hw, hh])
patch = mpatches.Rectangle(pos_xy, width, height, 0., **kwargs)
ax.add_patch(patch)
return ax
@staticmethod
def _calc_center(slices):
"""
Calculate the center position. The center position will be
fractional for even-sized arrays. For ``mode='partial'``, the
central position is calculated for the valid (non-filled) cutout
values.
"""
return tuple(0.5 * (slices[i].start + slices[i].stop - 1)
for i in [1, 0])
@staticmethod
def _calc_bbox(slices):
"""
Calculate a minimal bounding box in the form ``((ymin, ymax),
(xmin, xmax))``. Note these are pixel locations, not slice
indices. For ``mode='partial'``, the bounding box indices are
for the valid (non-filled) cutout values.
"""
# (stop - 1) to return the max pixel location, not the slice index
return ((slices[0].start, slices[0].stop - 1),
(slices[1].start, slices[1].stop - 1))
@lazyproperty
def origin_original(self):
"""
The ``(x, y)`` index of the origin pixel of the cutout with
respect to the original array. For ``mode='partial'``, the
origin pixel is calculated for the valid (non-filled) cutout
values.
"""
return (self.slices_original[1].start, self.slices_original[0].start)
@lazyproperty
def origin_cutout(self):
"""
The ``(x, y)`` index of the origin pixel of the cutout with
respect to the cutout array. For ``mode='partial'``, the origin
pixel is calculated for the valid (non-filled) cutout values.
"""
return (self.slices_cutout[1].start, self.slices_cutout[0].start)
@lazyproperty
def position_original(self):
"""
The ``(x, y)`` position index (rounded to the nearest pixel) in
the original array.
"""
return (_round(self.input_position_original[0]),
_round(self.input_position_original[1]))
@lazyproperty
def position_cutout(self):
"""
The ``(x, y)`` position index (rounded to the nearest pixel) in
the cutout array.
"""
return (_round(self.input_position_cutout[0]),
_round(self.input_position_cutout[1]))
@lazyproperty
def center_original(self):
"""
The central ``(x, y)`` position of the cutout array with respect
to the original array. For ``mode='partial'``, the central
position is calculated for the valid (non-filled) cutout values.
"""
return self._calc_center(self.slices_original)
@lazyproperty
def center_cutout(self):
"""
The central ``(x, y)`` position of the cutout array with respect
to the cutout array. For ``mode='partial'``, the central
position is calculated for the valid (non-filled) cutout values.
"""
return self._calc_center(self.slices_cutout)
@lazyproperty
def bbox_original(self):
"""
The bounding box ``((ymin, ymax), (xmin, xmax))`` of the minimal
rectangular region of the cutout array with respect to the
original array. For ``mode='partial'``, the bounding box
indices are for the valid (non-filled) cutout values.
"""
return self._calc_bbox(self.slices_original)
@lazyproperty
def bbox_cutout(self):
"""
The bounding box ``((ymin, ymax), (xmin, xmax))`` of the minimal
rectangular region of the cutout array with respect to the
cutout array. For ``mode='partial'``, the bounding box indices
are for the valid (non-filled) cutout values.
"""
return self._calc_bbox(self.slices_cutout)
|
9aaf4a56b98688be4b7355e0d6f5f3d82456884b0ac613ee6bb7d331076991a3 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
# This module contains a class equivalent to pre-1.0 NDData.
import numpy as np
from ..units import UnitsError, UnitConversionError, Unit
from .. import log
from .nddata import NDData
from .nduncertainty import NDUncertainty
from .mixins.ndslicing import NDSlicingMixin
from .mixins.ndarithmetic import NDArithmeticMixin
from .mixins.ndio import NDIOMixin
from .flag_collection import FlagCollection
__all__ = ['NDDataArray']
class NDDataArray(NDArithmeticMixin, NDSlicingMixin, NDIOMixin, NDData):
"""
An ``NDData`` object with arithmetic. This class is functionally equivalent
to ``NDData`` in astropy versions prior to 1.0.
The key distinction from raw numpy arrays is the presence of
additional metadata such as uncertainties, a mask, units, flags,
and/or a coordinate system.
Parameters
-----------
data : `~numpy.ndarray` or `NDData`
The actual data contained in this `NDData` object. Not that this
will always be copies by *reference* , so you should make copy
the ``data`` before passing it in if that's the desired behavior.
uncertainty : `~astropy.nddata.NDUncertainty`, optional
Uncertainties on the data.
mask : `~numpy.ndarray`-like, optional
Mask for the data, given as a boolean Numpy array or any object that
can be converted to a boolean Numpy array with a shape
matching that of the data. The values must be ``False`` where
the data is *valid* and ``True`` when it is not (like Numpy
masked arrays). If ``data`` is a numpy masked array, providing
``mask`` here will causes the mask from the masked array to be
ignored.
flags : `~numpy.ndarray`-like or `~astropy.nddata.FlagCollection`, optional
Flags giving information about each pixel. These can be specified
either as a Numpy array of any type (or an object which can be converted
to a Numpy array) with a shape matching that of the
data, or as a `~astropy.nddata.FlagCollection` instance which has a
shape matching that of the data.
wcs : undefined, optional
WCS-object containing the world coordinate system for the data.
.. warning::
This is not yet defind because the discussion of how best to
represent this class's WCS system generically is still under
consideration. For now just leave it as None
meta : `dict`-like object, optional
Metadata for this object. "Metadata" here means all information that
is included with this object but not part of any other attribute
of this particular object. e.g., creation date, unique identifier,
simulation parameters, exposure time, telescope name, etc.
unit : `~astropy.units.UnitBase` instance or str, optional
The units of the data.
Raises
------
ValueError :
If the `uncertainty` or `mask` inputs cannot be broadcast (e.g., match
shape) onto ``data``.
"""
def __init__(self, data, *args, flags=None, **kwargs):
# Initialize with the parent...
super().__init__(data, *args, **kwargs)
# ...then reset uncertainty to force it to go through the
# setter logic below. In base NDData all that is done is to
# set self._uncertainty to whatever uncertainty is passed in.
self.uncertainty = self._uncertainty
# Same thing for mask.
self.mask = self._mask
# Initial flags because it is no longer handled in NDData
# or NDDataBase.
if isinstance(data, NDDataArray):
if flags is None:
flags = data.flags
else:
log.info("Overwriting NDDataArrays's current "
"flags with specified flags")
self.flags = flags
# Implement uncertainty as NDUncertainty to support propagation of
# uncertainties in arithmetic operations
@property
def uncertainty(self):
return self._uncertainty
@uncertainty.setter
def uncertainty(self, value):
if value is not None:
if isinstance(value, NDUncertainty):
class_name = self.__class__.__name__
if self.unit and value._unit:
try:
scaling = (1 * value._unit).to(self.unit)
except UnitsError:
raise UnitConversionError(
'Cannot convert unit of uncertainty to unit of '
'{0} object.'.format(class_name))
value.array *= scaling
elif not self.unit and value._unit:
# Raise an error if uncertainty has unit and data does not
raise ValueError("Cannot assign an uncertainty with unit "
"to {0} without "
"a unit".format(class_name))
self._uncertainty = value
self._uncertainty.parent_nddata = self
else:
raise TypeError("Uncertainty must be an instance of "
"a NDUncertainty object")
else:
self._uncertainty = value
# Override unit so that we can add a setter.
@property
def unit(self):
return self._unit
@unit.setter
def unit(self, value):
from . import conf
try:
if self._unit is not None and conf.warn_setting_unit_directly:
log.info('Setting the unit directly changes the unit without '
'updating the data or uncertainty. Use the '
'.convert_unit_to() method to change the unit and '
'scale values appropriately.')
except AttributeError:
# raised if self._unit has not been set yet, in which case the
# warning is irrelevant
pass
if value is None:
self._unit = None
else:
self._unit = Unit(value)
# Implement mask in a way that converts nicely to a numpy masked array
@property
def mask(self):
if self._mask is np.ma.nomask:
return None
else:
return self._mask
@mask.setter
def mask(self, value):
# Check that value is not either type of null mask.
if (value is not None) and (value is not np.ma.nomask):
mask = np.array(value, dtype=np.bool_, copy=False)
if mask.shape != self.data.shape:
raise ValueError("dimensions of mask do not match data")
else:
self._mask = mask
else:
# internal representation should be one numpy understands
self._mask = np.ma.nomask
@property
def shape(self):
"""
shape tuple of this object's data.
"""
return self.data.shape
@property
def size(self):
"""
integer size of this object's data.
"""
return self.data.size
@property
def dtype(self):
"""
`numpy.dtype` of this object's data.
"""
return self.data.dtype
@property
def ndim(self):
"""
integer dimensions of this object's data
"""
return self.data.ndim
@property
def flags(self):
return self._flags
@flags.setter
def flags(self, value):
if value is not None:
if isinstance(value, FlagCollection):
if value.shape != self.shape:
raise ValueError("dimensions of FlagCollection does not match data")
else:
self._flags = value
else:
flags = np.array(value, copy=False)
if flags.shape != self.shape:
raise ValueError("dimensions of flags do not match data")
else:
self._flags = flags
else:
self._flags = value
def __array__(self):
"""
This allows code that requests a Numpy array to use an NDData
object as a Numpy array.
"""
if self.mask is not None:
return np.ma.masked_array(self.data, self.mask)
else:
return np.array(self.data)
def __array_prepare__(self, array, context=None):
"""
This ensures that a masked array is returned if self is masked.
"""
if self.mask is not None:
return np.ma.masked_array(array, self.mask)
else:
return array
def convert_unit_to(self, unit, equivalencies=[]):
"""
Returns a new `NDData` object whose values have been converted
to a new unit.
Parameters
----------
unit : `astropy.units.UnitBase` instance or str
The unit to convert to.
equivalencies : list of equivalence pairs, optional
A list of equivalence pairs to try if the units are not
directly convertible. See :ref:`unit_equivalencies`.
Returns
-------
result : `~astropy.nddata.NDData`
The resulting dataset
Raises
------
UnitsError
If units are inconsistent.
"""
if self.unit is None:
raise ValueError("No unit specified on source data")
data = self.unit.to(unit, self.data, equivalencies=equivalencies)
if self.uncertainty is not None:
uncertainty_values = self.unit.to(unit, self.uncertainty.array,
equivalencies=equivalencies)
# should work for any uncertainty class
uncertainty = self.uncertainty.__class__(uncertainty_values)
else:
uncertainty = None
if self.mask is not None:
new_mask = self.mask.copy()
else:
new_mask = None
# Call __class__ in case we are dealing with an inherited type
result = self.__class__(data, uncertainty=uncertainty,
mask=new_mask,
wcs=self.wcs,
meta=self.meta, unit=unit)
return result
|
8d1e51fff71704051e8dd5571178f6f889e5814a46e27e5de5d181a533dab62f | # Licensed under a 3-clause BSD style license - see LICENSE.rst
try:
# The ERFA wrappers are not guaranteed available at setup time
from .core import *
except ImportError:
if not _ASTROPY_SETUP_:
raise
|
a6c802ea2c89a4232cc6c6569300b6320a68e4e7ea2bb49aea0fb5bec446ae8a | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module's main purpose is to act as a script to create new versions
of erfa.c when ERFA is updated (or this generator is enhanced).
`Jinja2 <http://jinja.pocoo.org/>`_ must be installed for this
module/script to function.
Note that this does *not* currently automate the process of creating structs
or dtypes for those structs. They should be added manually in the template file.
"""
# note that we do *not* use unicode_literals here, because that makes the
# generated code's strings have u'' in them on py 2.x
import re
import os.path
from collections import OrderedDict
ctype_to_dtype = {'double': "numpy.double",
'int': "numpy.intc",
'eraASTROM': "dt_eraASTROM",
'eraLDBODY': "dt_eraLDBODY",
'char': "numpy.dtype('S1')",
'const char': "numpy.dtype('S16')",
}
NDIMS_REX = re.compile(re.escape("numpy.dtype([('fi0', '.*', <(.*)>)])").replace(r'\.\*', '.*').replace(r'\<', '(').replace(r'\>', ')'))
class FunctionDoc:
def __init__(self, doc):
self.doc = doc.replace("**", " ").replace("/*\n", "").replace("*/", "")
self.__input = None
self.__output = None
self.__ret_info = None
@property
def input(self):
if self.__input is None:
self.__input = []
result = re.search("Given([^\n]*):\n(.+?) \n", self.doc, re.DOTALL)
if result is not None:
__input = result.group(2)
for i in __input.split("\n"):
arg_doc = ArgumentDoc(i)
if arg_doc.name is not None:
self.__input.append(arg_doc)
result = re.search("Given and returned([^\n]*):\n(.+?) \n", self.doc, re.DOTALL)
if result is not None:
__input = result.group(2)
for i in __input.split("\n"):
arg_doc = ArgumentDoc(i)
if arg_doc.name is not None:
self.__input.append(arg_doc)
return self.__input
@property
def output(self):
if self.__output is None:
self.__output = []
result = re.search("Returned([^\n]*):\n(.+?) \n", self.doc, re.DOTALL)
if result is not None:
__output = result.group(2)
for i in __output.split("\n"):
arg_doc = ArgumentDoc(i)
if arg_doc.name is not None:
self.__output.append(arg_doc)
result = re.search("Given and returned([^\n]*):\n(.+?) \n", self.doc, re.DOTALL)
if result is not None:
__output = result.group(2)
for i in __output.split("\n"):
arg_doc = ArgumentDoc(i)
if arg_doc.name is not None:
self.__output.append(arg_doc)
return self.__output
@property
def ret_info(self):
if self.__ret_info is None:
ret_info = []
result = re.search("Returned \\(function value\\)([^\n]*):\n(.+?) \n", self.doc, re.DOTALL)
if result is not None:
ret_info.append(ReturnDoc(result.group(2)))
if len(ret_info) == 0:
self.__ret_info = ''
elif len(ret_info) == 1:
self.__ret_info = ret_info[0]
else:
raise ValueError("Multiple C return sections found in this doc:\n" + self.doc)
return self.__ret_info
def __repr__(self):
return self.doc.replace(" \n", "\n")
class ArgumentDoc:
def __init__(self, doc):
match = re.search("^ +([^ ]+)[ ]+([^ ]+)[ ]+(.+)", doc)
if match is not None:
self.name = match.group(1)
self.type = match.group(2)
self.doc = match.group(3)
else:
self.name = None
self.type = None
self.doc = None
def __repr__(self):
return " {0:15} {1:15} {2}".format(self.name, self.type, self.doc)
class Argument:
def __init__(self, definition, doc):
self.doc = doc
self.__inout_state = None
self.ctype, ptr_name_arr = definition.strip().rsplit(" ", 1)
if "*" == ptr_name_arr[0]:
self.is_ptr = True
name_arr = ptr_name_arr[1:]
else:
self.is_ptr = False
name_arr = ptr_name_arr
if "[]" in ptr_name_arr:
self.is_ptr = True
name_arr = name_arr[:-2]
if "[" in name_arr:
self.name, arr = name_arr.split("[", 1)
self.shape = tuple([int(size) for size in arr[:-1].split("][")])
else:
self.name = name_arr
self.shape = ()
@property
def inout_state(self):
if self.__inout_state is None:
self.__inout_state = ''
for i in self.doc.input:
if self.name in i.name.split(','):
self.__inout_state = 'in'
for o in self.doc.output:
if self.name in o.name.split(','):
if self.__inout_state == 'in':
self.__inout_state = 'inout'
else:
self.__inout_state = 'out'
return self.__inout_state
@property
def ctype_ptr(self):
if (self.is_ptr) | (len(self.shape) > 0):
return self.ctype+" *"
else:
return self.ctype
@property
def name_in_broadcast(self):
if len(self.shape) > 0:
return "{0}_in[...{1}]".format(self.name, ",0"*len(self.shape))
else:
return "{0}_in".format(self.name)
@property
def name_out_broadcast(self):
if len(self.shape) > 0:
return "{0}_out[...{1}]".format(self.name, ",0"*len(self.shape))
else:
return "{0}_out".format(self.name)
@property
def dtype(self):
return ctype_to_dtype[self.ctype]
@property
def ndim(self):
return len(self.shape)
@property
def cshape(self):
return ''.join(['[{0}]'.format(s) for s in self.shape])
@property
def name_for_call(self):
if self.is_ptr:
return '_'+self.name
else:
return '*_'+self.name
def __repr__(self):
return "Argument('{0}', name='{1}', ctype='{2}', inout_state='{3}')".format(self.definition, self.name, self.ctype, self.inout_state)
class ReturnDoc:
def __init__(self, doc):
self.doc = doc
self.infoline = doc.split('\n')[0].strip()
self.type = self.infoline.split()[0]
self.descr = self.infoline.split()[1]
if self.descr.startswith('status'):
self.statuscodes = statuscodes = {}
code = None
for line in doc[doc.index(':')+1:].split('\n'):
ls = line.strip()
if ls != '':
if ' = ' in ls:
code, msg = ls.split(' = ')
if code != 'else':
code = int(code)
statuscodes[code] = msg
elif code is not None:
statuscodes[code] += ls
else:
self.statuscodes = None
def __repr__(self):
return "Return value, type={0:15}, {1}, {2}".format(self.type, self.descr, self.doc)
class Return:
def __init__(self, ctype, doc):
self.name = 'c_retval'
self.name_out_broadcast = self.name+"_out"
self.inout_state = 'stat' if ctype == 'int' else 'ret'
self.ctype = ctype
self.ctype_ptr = ctype
self.shape = ()
self.doc = doc
def __repr__(self):
return "Return(name='{0}', ctype='{1}', inout_state='{2}')".format(self.name, self.ctype, self.inout_state)
@property
def dtype(self):
return ctype_to_dtype[self.ctype]
@property
def nd_dtype(self):
"""
This if the return type has a multi-dimensional output, like
double[3][3]
"""
return "'fi0'" in self.dtype
@property
def doc_info(self):
return self.doc.ret_info
class Function:
"""
A class representing a C function.
Parameters
----------
name : str
The name of the function
source_path : str
Either a directory, which means look for the function in a
stand-alone file (like for the standard ERFA distribution), or a
file, which means look for the function in that file (as for the
astropy-packaged single-file erfa.c).
match_line : str, optional
If given, searching of the source file will skip until it finds
a line matching this string, and start from there.
"""
def __init__(self, name, source_path, match_line=None):
self.name = name
self.pyname = name.split('era')[-1].lower()
self.filename = self.pyname+".c"
if os.path.isdir(source_path):
self.filepath = os.path.join(os.path.normpath(source_path), self.filename)
else:
self.filepath = source_path
with open(self.filepath) as f:
if match_line:
line = f.readline()
while line != '':
if line.startswith(match_line):
filecontents = '\n' + line + f.read()
break
line = f.readline()
else:
msg = ('Could not find the match_line "{0}" in '
'the source file "{1}"')
raise ValueError(msg.format(match_line, self.filepath))
else:
filecontents = f.read()
pattern = r"\n([^\n]+{0} ?\([^)]+\)).+?(/\*.+?\*/)".format(name)
p = re.compile(pattern, flags=re.DOTALL | re.MULTILINE)
search = p.search(filecontents)
self.cfunc = " ".join(search.group(1).split())
self.doc = FunctionDoc(search.group(2))
self.args = []
for arg in re.search(r"\(([^)]+)\)", self.cfunc).group(1).split(', '):
self.args.append(Argument(arg, self.doc))
self.ret = re.search("^(.*){0}".format(name), self.cfunc).group(1).strip()
if self.ret != 'void':
self.args.append(Return(self.ret, self.doc))
def args_by_inout(self, inout_filter, prop=None, join=None):
"""
Gives all of the arguments and/or returned values, depending on whether
they are inputs, outputs, etc.
The value for `inout_filter` should be a string containing anything
that arguments' `inout_state` attribute produces. Currently, that can be:
* "in" : input
* "out" : output
* "inout" : something that's could be input or output (e.g. a struct)
* "ret" : the return value of the C function
* "stat" : the return value of the C function if it is a status code
It can also be a "|"-separated string giving inout states to OR
together.
"""
result = []
for arg in self.args:
if arg.inout_state in inout_filter.split('|'):
if prop is None:
result.append(arg)
else:
result.append(getattr(arg, prop))
if join is not None:
return join.join(result)
else:
return result
def __repr__(self):
return "Function(name='{0}', pyname='{1}', filename='{2}', filepath='{3}')".format(self.name, self.pyname, self.filename, self.filepath)
class Constant:
def __init__(self, name, value, doc):
self.name = name.replace("ERFA_", "")
self.value = value.replace("ERFA_", "")
self.doc = doc
class ExtraFunction(Function):
"""
An "extra" function - e.g. one not following the SOFA/ERFA standard format.
Parameters
----------
cname : str
The name of the function in C
prototype : str
The prototype for the function (usually derived from the header)
pathfordoc : str
The path to a file that contains the prototype, with the documentation
as a multiline string *before* it.
"""
def __init__(self, cname, prototype, pathfordoc):
self.name = cname
self.pyname = cname.split('era')[-1].lower()
self.filepath, self.filename = os.path.split(pathfordoc)
self.prototype = prototype.strip()
if prototype.endswith('{') or prototype.endswith(';'):
self.prototype = prototype[:-1].strip()
incomment = False
lastcomment = None
with open(pathfordoc, 'r') as f:
for l in f:
if incomment:
if l.lstrip().startswith('*/'):
incomment = False
lastcomment = ''.join(lastcomment)
else:
if l.startswith('**'):
l = l[2:]
lastcomment.append(l)
else:
if l.lstrip().startswith('/*'):
incomment = True
lastcomment = []
if l.startswith(self.prototype):
self.doc = lastcomment
break
else:
raise ValueError('Did not find prototype {} in file '
'{}'.format(self.prototype, pathfordoc))
self.args = []
argset = re.search(r"{0}\(([^)]+)?\)".format(self.name),
self.prototype).group(1)
if argset is not None:
for arg in argset.split(', '):
self.args.append(Argument(arg, self.doc))
self.ret = re.match("^(.*){0}".format(self.name),
self.prototype).group(1).strip()
if self.ret != 'void':
self.args.append(Return(self.ret, self.doc))
def __repr__(self):
r = super().__repr__()
if r.startswith('Function'):
r = 'Extra' + r
return r
def main(srcdir, outfn, templateloc, verbose=True):
from jinja2 import Environment, FileSystemLoader
if verbose:
print_ = lambda *args, **kwargs: print(*args, **kwargs)
else:
print_ = lambda *args, **kwargs: None
# Prepare the jinja2 templating environment
env = Environment(loader=FileSystemLoader(templateloc))
def prefix(a_list, pre):
return [pre+'{0}'.format(an_element) for an_element in a_list]
def postfix(a_list, post):
return ['{0}'.format(an_element)+post for an_element in a_list]
def surround(a_list, pre, post):
return [pre+'{0}'.format(an_element)+post for an_element in a_list]
env.filters['prefix'] = prefix
env.filters['postfix'] = postfix
env.filters['surround'] = surround
erfa_c_in = env.get_template('core.c.templ')
erfa_py_in = env.get_template('core.py.templ')
# Extract all the ERFA function names from erfa.h
if os.path.isdir(srcdir):
erfahfn = os.path.join(srcdir, 'erfa.h')
multifilserc = True
else:
erfahfn = os.path.join(os.path.split(srcdir)[0], 'erfa.h')
multifilserc = False
with open(erfahfn, "r") as f:
erfa_h = f.read()
funcs = OrderedDict()
section_subsection_functions = re.findall(r'/\* (\w*)/(\w*) \*/\n(.*?)\n\n',
erfa_h, flags=re.DOTALL | re.MULTILINE)
for section, subsection, functions in section_subsection_functions:
print_("{0}.{1}".format(section, subsection))
if ((section == "Astronomy") or (subsection == "AngleOps")
or (subsection == "SphericalCartesian")
or (subsection == "MatrixVectorProducts")):
func_names = re.findall(r' (\w+)\(.*?\);', functions, flags=re.DOTALL)
for name in func_names:
print_("{0}.{1}.{2}...".format(section, subsection, name))
if multifilserc:
# easy because it just looks in the file itself
funcs[name] = Function(name, srcdir)
else:
# Have to tell it to look for a declaration matching
# the start of the header declaration, otherwise it
# might find a *call* of the function instead of the
# definition
for line in functions.split(r'\n'):
if name in line:
# [:-1] is to remove trailing semicolon, and
# splitting on '(' is because the header and
# C files don't necessarily have to match
# argument names and line-breaking or
# whitespace
match_line = line[:-1].split('(')[0]
funcs[name] = Function(name, srcdir, match_line)
break
else:
raise ValueError("A name for a C file wasn't "
"found in the string that "
"spawned it. This should be "
"impossible!")
funcs = list(funcs.values())
# Extract all the ERFA constants from erfam.h
erfamhfn = os.path.join(srcdir, 'erfam.h')
with open(erfamhfn, 'r') as f:
erfa_m_h = f.read()
constants = []
for chunk in erfa_m_h.split("\n\n"):
result = re.findall(r"#define (ERFA_\w+?) (.+?)$", chunk, flags=re.DOTALL | re.MULTILINE)
if result:
doc = re.findall(r"/\* (.+?) \*/\n", chunk, flags=re.DOTALL)
for (name, value) in result:
constants.append(Constant(name, value, doc))
# TODO: re-enable this when const char* return values and non-status code integer rets are possible
# #Add in any "extra" functions from erfaextra.h
# erfaextrahfn = os.path.join(srcdir, 'erfaextra.h')
# with open(erfaextrahfn, 'r') as f:
# for l in f:
# ls = l.strip()
# match = re.match('.* (era.*)\(', ls)
# if match:
# print_("Extra: {0} ...".format(match.group(1)))
# funcs.append(ExtraFunction(match.group(1), ls, erfaextrahfn))
print_("Rendering template")
erfa_c = erfa_c_in.render(funcs=funcs)
erfa_py = erfa_py_in.render(funcs=funcs, constants=constants)
if outfn is not None:
outfn_c = os.path.splitext(outfn)[0] + ".c"
print_("Saving to", outfn, 'and', outfn_c)
with open(outfn, "w") as f:
f.write(erfa_py)
with open(outfn_c, "w") as f:
f.write(erfa_c)
print_("Done!")
return erfa_c, erfa_py, funcs
DEFAULT_ERFA_LOC = os.path.join(os.path.split(__file__)[0],
'../../cextern/erfa')
DEFAULT_TEMPLATE_LOC = os.path.split(__file__)[0]
if __name__ == '__main__':
from argparse import ArgumentParser
ap = ArgumentParser()
ap.add_argument('srcdir', default=DEFAULT_ERFA_LOC, nargs='?',
help='Directory where the ERFA c and header files '
'can be found or to a single erfa.c file '
'(which must be in the same directory as '
'erfa.h). Defaults to the builtin astropy '
'erfa: "{0}"'.format(DEFAULT_ERFA_LOC))
ap.add_argument('-o', '--output', default='core.py',
help='The output filename. This is the name for only the '
'pure-python output, the C part will have the '
'same name but with a ".c" extension.')
ap.add_argument('-t', '--template-loc',
default=DEFAULT_TEMPLATE_LOC,
help='the location where the "core.c.templ" '
'template can be found.')
ap.add_argument('-q', '--quiet', action='store_false', dest='verbose',
help='Suppress output normally printed to stdout.')
args = ap.parse_args()
main(args.srcdir, args.output, args.template_loc)
|
8fd36b492cbee8454f9cbee7fd14dbb5892d80cc2e2a04325e905b9d67feb423 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
import os
import glob
from distutils import log
from distutils.extension import Extension
from astropy_helpers import setup_helpers
from astropy_helpers.version_helpers import get_pkg_version_module
ERFAPKGDIR = os.path.relpath(os.path.dirname(__file__))
ERFA_SRC = os.path.abspath(os.path.join(ERFAPKGDIR, '..', '..', 'cextern', 'erfa'))
SRC_FILES = glob.glob(os.path.join(ERFA_SRC, '*'))
SRC_FILES += [os.path.join(ERFAPKGDIR, filename)
for filename in ['core.py.templ', 'core.c.templ', 'erfa_generator.py']]
GEN_FILES = [os.path.join(ERFAPKGDIR, 'core.py'), os.path.join(ERFAPKGDIR, 'core.c')]
def pre_build_py_hook(cmd_obj):
preprocess_source()
def pre_build_ext_hook(cmd_obj):
preprocess_source()
def pre_sdist_hook(cmd_obj):
preprocess_source()
def preprocess_source():
# Generating the ERFA wrappers should only be done if needed. This also
# ensures that it is not done for any release tarball since those will
# include core.py and core.c.
if all(os.path.exists(filename) for filename in GEN_FILES):
# Determine modification times
erfa_mtime = max(os.path.getmtime(filename) for filename in SRC_FILES)
gen_mtime = min(os.path.getmtime(filename) for filename in GEN_FILES)
version = get_pkg_version_module('astropy')
if gen_mtime > erfa_mtime:
# If generated source is recent enough, don't update
return
elif version.release:
# or, if we're on a release, issue a warning, but go ahead and use
# the wrappers anyway
log.warn('WARNING: The autogenerated wrappers in astropy._erfa '
'seem to be older than the source templates used to '
'create them. Because this is a release version we will '
'use them anyway, but this might be a sign of some sort '
'of version mismatch or other tampering. Or it might just '
'mean you moved some files around or otherwise '
'accidentally changed timestamps.')
return
# otherwise rebuild the autogenerated files
# If jinja2 isn't present, then print a warning and use existing files
try:
import jinja2 # pylint: disable=W0611
except ImportError:
log.warn("WARNING: jinja2 could not be imported, so the existing "
"ERFA core.py and core.c files will be used")
return
name = 'erfa_generator'
filename = os.path.join(ERFAPKGDIR, 'erfa_generator.py')
try:
from importlib import machinery as import_machinery
loader = import_machinery.SourceFileLoader(name, filename)
gen = loader.load_module()
except ImportError:
import imp
gen = imp.load_source(name, filename)
gen.main(gen.DEFAULT_ERFA_LOC,
os.path.join(ERFAPKGDIR, 'core.py'),
gen.DEFAULT_TEMPLATE_LOC,
verbose=False)
def get_extensions():
sources = [os.path.join(ERFAPKGDIR, "core.c")]
include_dirs = ['numpy']
libraries = []
if setup_helpers.use_system_library('erfa'):
libraries.append('erfa')
else:
# get all of the .c files in the cextern/erfa directory
erfafns = os.listdir(ERFA_SRC)
sources.extend(['cextern/erfa/'+fn for fn in erfafns if fn.endswith('.c')])
include_dirs.append('cextern/erfa')
erfa_ext = Extension(
name="astropy._erfa._core",
sources=sources,
include_dirs=include_dirs,
libraries=libraries,
language="c",)
return [erfa_ext]
def get_external_libraries():
return ['erfa']
|
ed0831132c31d356d8a553e0e77a8845908e345ce33a94bcd684a87dc3e72ab8 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
.. _wcslib: http://www.atnf.csiro.au/people/mcalabre/WCS/wcslib/index.html
.. _distortion paper: http://www.atnf.csiro.au/people/mcalabre/WCS/dcs_20040422.pdf
.. _SIP: http://irsa.ipac.caltech.edu/data/SPITZER/docs/files/spitzer/shupeADASS.pdf
.. _FITS WCS standard: https://fits.gsfc.nasa.gov/fits_wcs.html
`astropy.wcs` contains utilities for managing World Coordinate System
(WCS) transformations in FITS files. These transformations map the
pixel locations in an image to their real-world units, such as their
position on the sky sphere.
It performs three separate classes of WCS transformations:
- Core WCS, as defined in the `FITS WCS standard`_, based on Mark
Calabretta's `wcslib`_. See `~astropy.wcs.Wcsprm`.
- Simple Imaging Polynomial (`SIP`_) convention. See
`~astropy.wcs.Sip`.
- table lookup distortions as defined in WCS `distortion paper`_. See
`~astropy.wcs.DistortionLookupTable`.
Each of these transformations can be used independently or together in
a standard pipeline.
"""
try:
# Not guaranteed available at setup time
from .wcs import *
from . import utils
except ImportError:
if not _ASTROPY_SETUP_:
raise
def get_include():
"""
Get the path to astropy.wcs's C header files.
"""
import os
return os.path.join(os.path.dirname(__file__), "include")
|
c3d6fdb8592c828c9798928a53c34479ce97a51704c97b552887dc1e33304725 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
astropy.wcs-specific utilities for generating boilerplate in docstrings.
"""
__all__ = ['TWO_OR_THREE_ARGS', 'RETURNS', 'ORIGIN', 'RA_DEC_ORDER']
def _fix(content, indent=0):
lines = content.split('\n')
indent = '\n' + ' ' * indent
return indent.join(lines)
def TWO_OR_MORE_ARGS(naxis, indent=0):
return _fix(
"""args : flexible
There are two accepted forms for the positional arguments:
- 2 arguments: An *N* x *{0}* array of coordinates, and an
*origin*.
- more than 2 arguments: An array for each axis, followed by
an *origin*. These arrays must be broadcastable to one
another.
Here, *origin* is the coordinate in the upper left corner of the
image. In FITS and Fortran standards, this is 1. In Numpy and C
standards this is 0.
""".format(naxis), indent)
def RETURNS(out_type, indent=0):
return _fix("""result : array
Returns the {0}. If the input was a single array and
origin, a single array is returned, otherwise a tuple of arrays is
returned.""".format(out_type), indent)
def ORIGIN(indent=0):
return _fix(
"""
origin : int
Specifies the origin of pixel values. The Fortran and FITS
standards use an origin of 1. Numpy and C use array indexing with
origin at 0.
""", indent)
def RA_DEC_ORDER(indent=0):
return _fix(
"""
ra_dec_order : bool, optional
When `True` will ensure that world coordinates are always given
and returned in as (*ra*, *dec*) pairs, regardless of the order of
the axes specified by the in the ``CTYPE`` keywords. Default is
`False`.
""", indent)
|
84009b489b3969e03a8f39075818ee1d874f3042b594bdf033a8ed38dca4715d | # Licensed under a 3-clause BSD style license - see LICENSE.rst
CONTACT = "Michael Droettboom"
EMAIL = "[email protected]"
import io
from os.path import join
import os.path
import shutil
import sys
from distutils.core import Extension
from distutils.dep_util import newer_group
from astropy_helpers import setup_helpers
from astropy_helpers.distutils_helpers import get_distutils_build_option
WCSROOT = os.path.relpath(os.path.dirname(__file__))
WCSVERSION = "5.18"
def b(s):
return s.encode('ascii')
def string_escape(s):
s = s.decode('ascii').encode('ascii', 'backslashreplace')
s = s.replace(b'\n', b'\\n')
s = s.replace(b'\0', b'\\0')
return s.decode('ascii')
def determine_64_bit_int():
"""
The only configuration parameter needed at compile-time is how to
specify a 64-bit signed integer. Python's ctypes module can get us
that information.
If we can't be absolutely certain, we default to "long long int",
which is correct on most platforms (x86, x86_64). If we find
platforms where this heuristic doesn't work, we may need to
hardcode for them.
"""
try:
try:
import ctypes
except ImportError:
raise ValueError()
if ctypes.sizeof(ctypes.c_longlong) == 8:
return "long long int"
elif ctypes.sizeof(ctypes.c_long) == 8:
return "long int"
elif ctypes.sizeof(ctypes.c_int) == 8:
return "int"
else:
raise ValueError()
except ValueError:
return "long long int"
def write_wcsconfig_h(paths):
"""
Writes out the wcsconfig.h header with local configuration.
"""
h_file = io.StringIO()
h_file.write("""
/* The bundled version has WCSLIB_VERSION */
#define HAVE_WCSLIB_VERSION 1
/* WCSLIB library version number. */
#define WCSLIB_VERSION {0}
/* 64-bit integer data type. */
#define WCSLIB_INT64 {1}
/* Windows needs some other defines to prevent inclusion of wcsset()
which conflicts with wcslib's wcsset(). These need to be set
on code that *uses* astropy.wcs, in addition to astropy.wcs itself.
*/
#if defined(_WIN32) || defined(_MSC_VER) || defined(__MINGW32__) || defined (__MINGW64__)
#ifndef YY_NO_UNISTD_H
#define YY_NO_UNISTD_H
#endif
#ifndef _CRT_SECURE_NO_WARNINGS
#define _CRT_SECURE_NO_WARNINGS
#endif
#ifndef _NO_OLDNAMES
#define _NO_OLDNAMES
#endif
#ifndef NO_OLDNAMES
#define NO_OLDNAMES
#endif
#ifndef __STDC__
#define __STDC__ 1
#endif
#endif
""".format(WCSVERSION, determine_64_bit_int()))
content = h_file.getvalue().encode('ascii')
for path in paths:
setup_helpers.write_if_different(path, content)
######################################################################
# GENERATE DOCSTRINGS IN C
def generate_c_docstrings():
from astropy.wcs import docstrings
docstrings = docstrings.__dict__
keys = [
key for key, val in docstrings.items()
if not key.startswith('__') and isinstance(val, str)]
keys.sort()
docs = {}
for key in keys:
docs[key] = docstrings[key].encode('utf8').lstrip() + b'\0'
h_file = io.StringIO()
h_file.write("""/*
DO NOT EDIT!
This file is autogenerated by astropy/wcs/setup_package.py. To edit
its contents, edit astropy/wcs/docstrings.py
*/
#ifndef __DOCSTRINGS_H__
#define __DOCSTRINGS_H__
""")
for key in keys:
val = docs[key]
h_file.write('extern char doc_{0}[{1}];\n'.format(key, len(val)))
h_file.write("\n#endif\n\n")
setup_helpers.write_if_different(
join(WCSROOT, 'include', 'astropy_wcs', 'docstrings.h'),
h_file.getvalue().encode('utf-8'))
c_file = io.StringIO()
c_file.write("""/*
DO NOT EDIT!
This file is autogenerated by astropy/wcs/setup_package.py. To edit
its contents, edit astropy/wcs/docstrings.py
The weirdness here with strncpy is because some C compilers, notably
MSVC, do not support string literals greater than 256 characters.
*/
#include <string.h>
#include "astropy_wcs/docstrings.h"
""")
for key in keys:
val = docs[key]
c_file.write('char doc_{0}[{1}] = {{\n'.format(key, len(val)))
for i in range(0, len(val), 12):
section = val[i:i+12]
c_file.write(' ')
c_file.write(''.join('0x{0:02x}, '.format(x) for x in section))
c_file.write('\n')
c_file.write(" };\n\n")
setup_helpers.write_if_different(
join(WCSROOT, 'src', 'docstrings.c'),
c_file.getvalue().encode('utf-8'))
def get_wcslib_cfg(cfg, wcslib_files, include_paths):
from astropy.version import debug
cfg['include_dirs'].append('numpy')
cfg['define_macros'].extend([
('ECHO', None),
('WCSTRIG_MACRO', None),
('ASTROPY_WCS_BUILD', None),
('_GNU_SOURCE', None)])
if (not setup_helpers.use_system_library('wcslib') or
sys.platform == 'win32'):
write_wcsconfig_h(include_paths)
wcslib_path = join("cextern", "wcslib") # Path to wcslib
wcslib_cpath = join(wcslib_path, "C") # Path to wcslib source files
cfg['sources'].extend(join(wcslib_cpath, x) for x in wcslib_files)
cfg['include_dirs'].append(wcslib_cpath)
else:
wcsconfig_h_path = join(WCSROOT, 'include', 'wcsconfig.h')
if os.path.exists(wcsconfig_h_path):
os.unlink(wcsconfig_h_path)
cfg.update(setup_helpers.pkg_config(['wcslib'], ['wcs']))
if debug:
cfg['define_macros'].append(('DEBUG', None))
cfg['undef_macros'].append('NDEBUG')
if (not sys.platform.startswith('sun') and
not sys.platform == 'win32'):
cfg['extra_compile_args'].extend(["-fno-inline", "-O0", "-g"])
else:
# Define ECHO as nothing to prevent spurious newlines from
# printing within the libwcs parser
cfg['define_macros'].append(('NDEBUG', None))
cfg['undef_macros'].append('DEBUG')
if sys.platform == 'win32':
# These are written into wcsconfig.h, but that file is not
# used by all parts of wcslib.
cfg['define_macros'].extend([
('YY_NO_UNISTD_H', None),
('_CRT_SECURE_NO_WARNINGS', None),
('_NO_OLDNAMES', None), # for mingw32
('NO_OLDNAMES', None), # for mingw64
('__STDC__', None) # for MSVC
])
if sys.platform.startswith('linux'):
cfg['define_macros'].append(('HAVE_SINCOS', None))
# Squelch a few compilation warnings in WCSLIB
if setup_helpers.get_compiler_option() in ('unix', 'mingw32'):
if not get_distutils_build_option('debug'):
cfg['extra_compile_args'].extend([
'-Wno-strict-prototypes',
'-Wno-unused-function',
'-Wno-unused-value',
'-Wno-uninitialized'])
def get_extensions():
generate_c_docstrings()
######################################################################
# DISTUTILS SETUP
cfg = setup_helpers.DistutilsExtensionArgs()
wcslib_files = [ # List of wcslib files to compile
'flexed/wcsbth.c',
'flexed/wcspih.c',
'flexed/wcsulex.c',
'flexed/wcsutrn.c',
'cel.c',
'dis.c',
'lin.c',
'log.c',
'prj.c',
'spc.c',
'sph.c',
'spx.c',
'tab.c',
'wcs.c',
'wcserr.c',
'wcsfix.c',
'wcshdr.c',
'wcsprintf.c',
'wcsunits.c',
'wcsutil.c'
]
wcslib_config_paths = [
join(WCSROOT, 'include', 'astropy_wcs', 'wcsconfig.h'),
join(WCSROOT, 'include', 'wcsconfig.h')
]
get_wcslib_cfg(cfg, wcslib_files, wcslib_config_paths)
cfg['include_dirs'].append(join(WCSROOT, "include"))
astropy_wcs_files = [ # List of astropy.wcs files to compile
'distortion.c',
'distortion_wrap.c',
'docstrings.c',
'pipeline.c',
'pyutil.c',
'astropy_wcs.c',
'astropy_wcs_api.c',
'sip.c',
'sip_wrap.c',
'str_list_proxy.c',
'unit_list_proxy.c',
'util.c',
'wcslib_wrap.c',
'wcslib_tabprm_wrap.c']
cfg['sources'].extend(join(WCSROOT, 'src', x) for x in astropy_wcs_files)
cfg['sources'] = [str(x) for x in cfg['sources']]
cfg = dict((str(key), val) for key, val in cfg.items())
return [Extension(str('astropy.wcs._wcs'), **cfg)]
def get_package_data():
# Installs the testing data files
api_files = [
'astropy_wcs.h',
'astropy_wcs_api.h',
'distortion.h',
'isnan.h',
'pipeline.h',
'pyutil.h',
'sip.h',
'util.h',
'wcsconfig.h',
]
api_files = [join('include', 'astropy_wcs', x) for x in api_files]
api_files.append(join('include', 'astropy_wcs_api.h'))
wcslib_headers = [
'cel.h',
'lin.h',
'prj.h',
'spc.h',
'spx.h',
'tab.h',
'wcs.h',
'wcserr.h',
'wcsmath.h',
'wcsprintf.h',
]
if not setup_helpers.use_system_library('wcslib'):
for header in wcslib_headers:
source = join('cextern', 'wcslib', 'C', header)
dest = join('astropy', 'wcs', 'include', 'wcslib', header)
if newer_group([source], dest, 'newer'):
shutil.copy(source, dest)
api_files.append(join('include', 'wcslib', header))
return {
str('astropy.wcs.tests'): ['data/*.hdr', 'data/*.fits',
'data/*.txt', 'data/*.fits.gz',
'maps/*.hdr', 'spectra/*.hdr',
'extension/*.c'],
str('astropy.wcs'): api_files,
}
def get_external_libraries():
return ['wcslib']
|
faea432f172953f216c5cd889ea0aa5ae943460adea4d4360d0df48935492bc1 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
import numpy as np
from .. import units as u
from .wcs import WCS, WCSSUB_CELESTIAL
__doctest_skip__ = ['wcs_to_celestial_frame', 'celestial_frame_to_wcs']
__all__ = ['add_stokes_axis_to_wcs', 'celestial_frame_to_wcs',
'wcs_to_celestial_frame', 'proj_plane_pixel_scales',
'proj_plane_pixel_area', 'is_proj_plane_distorted',
'non_celestial_pixel_scales', 'skycoord_to_pixel',
'pixel_to_skycoord', 'custom_wcs_to_frame_mappings',
'custom_frame_to_wcs_mappings']
def add_stokes_axis_to_wcs(wcs, add_before_ind):
"""
Add a new Stokes axis that is uncorrelated with any other axes.
Parameters
----------
wcs : `~astropy.wcs.WCS`
The WCS to add to
add_before_ind : int
Index of the WCS to insert the new Stokes axis in front of.
To add at the end, do add_before_ind = wcs.wcs.naxis
The beginning is at position 0.
Returns
-------
A new `~astropy.wcs.WCS` instance with an additional axis
"""
inds = [i + 1 for i in range(wcs.wcs.naxis)]
inds.insert(add_before_ind, 0)
newwcs = wcs.sub(inds)
newwcs.wcs.ctype[add_before_ind] = 'STOKES'
newwcs.wcs.cname[add_before_ind] = 'STOKES'
return newwcs
def _wcs_to_celestial_frame_builtin(wcs):
# Import astropy.coordinates here to avoid circular imports
from ..coordinates import FK4, FK4NoETerms, FK5, ICRS, Galactic
# Import astropy.time here otherwise setup.py fails before extensions are compiled
from ..time import Time
# Keep only the celestial part of the axes
wcs = wcs.sub([WCSSUB_CELESTIAL])
if wcs.wcs.lng == -1 or wcs.wcs.lat == -1:
return None
radesys = wcs.wcs.radesys
if np.isnan(wcs.wcs.equinox):
equinox = None
else:
equinox = wcs.wcs.equinox
xcoord = wcs.wcs.ctype[0][:4]
ycoord = wcs.wcs.ctype[1][:4]
# Apply logic from FITS standard to determine the default radesys
if radesys == '' and xcoord == 'RA--' and ycoord == 'DEC-':
if equinox is None:
radesys = "ICRS"
elif equinox < 1984.:
radesys = "FK4"
else:
radesys = "FK5"
if radesys == 'FK4':
if equinox is not None:
equinox = Time(equinox, format='byear')
frame = FK4(equinox=equinox)
elif radesys == 'FK4-NO-E':
if equinox is not None:
equinox = Time(equinox, format='byear')
frame = FK4NoETerms(equinox=equinox)
elif radesys == 'FK5':
if equinox is not None:
equinox = Time(equinox, format='jyear')
frame = FK5(equinox=equinox)
elif radesys == 'ICRS':
frame = ICRS()
else:
if xcoord == 'GLON' and ycoord == 'GLAT':
frame = Galactic()
else:
frame = None
return frame
def _celestial_frame_to_wcs_builtin(frame, projection='TAN'):
# Import astropy.coordinates here to avoid circular imports
from ..coordinates import BaseRADecFrame, FK4, FK4NoETerms, FK5, ICRS, Galactic
# Create a 2-dimensional WCS
wcs = WCS(naxis=2)
if isinstance(frame, BaseRADecFrame):
xcoord = 'RA--'
ycoord = 'DEC-'
if isinstance(frame, ICRS):
wcs.wcs.radesys = 'ICRS'
elif isinstance(frame, FK4NoETerms):
wcs.wcs.radesys = 'FK4-NO-E'
wcs.wcs.equinox = frame.equinox.byear
elif isinstance(frame, FK4):
wcs.wcs.radesys = 'FK4'
wcs.wcs.equinox = frame.equinox.byear
elif isinstance(frame, FK5):
wcs.wcs.radesys = 'FK5'
wcs.wcs.equinox = frame.equinox.jyear
else:
return None
elif isinstance(frame, Galactic):
xcoord = 'GLON'
ycoord = 'GLAT'
else:
return None
wcs.wcs.ctype = [xcoord + '-' + projection, ycoord + '-' + projection]
return wcs
WCS_FRAME_MAPPINGS = [[_wcs_to_celestial_frame_builtin]]
FRAME_WCS_MAPPINGS = [[_celestial_frame_to_wcs_builtin]]
class custom_wcs_to_frame_mappings:
def __init__(self, mappings=[]):
if hasattr(mappings, '__call__'):
mappings = [mappings]
WCS_FRAME_MAPPINGS.append(mappings)
def __enter__(self):
pass
def __exit__(self, type, value, tb):
WCS_FRAME_MAPPINGS.pop()
# Backward-compatibility
custom_frame_mappings = custom_wcs_to_frame_mappings
class custom_frame_to_wcs_mappings:
def __init__(self, mappings=[]):
if hasattr(mappings, '__call__'):
mappings = [mappings]
FRAME_WCS_MAPPINGS.append(mappings)
def __enter__(self):
pass
def __exit__(self, type, value, tb):
FRAME_WCS_MAPPINGS.pop()
def wcs_to_celestial_frame(wcs):
"""
For a given WCS, return the coordinate frame that matches the celestial
component of the WCS.
Parameters
----------
wcs : :class:`~astropy.wcs.WCS` instance
The WCS to find the frame for
Returns
-------
frame : :class:`~astropy.coordinates.baseframe.BaseCoordinateFrame` subclass instance
An instance of a :class:`~astropy.coordinates.baseframe.BaseCoordinateFrame`
subclass instance that best matches the specified WCS.
Notes
-----
To extend this function to frames not defined in astropy.coordinates, you
can write your own function which should take a :class:`~astropy.wcs.WCS`
instance and should return either an instance of a frame, or `None` if no
matching frame was found. You can register this function temporarily with::
>>> from astropy.wcs.utils import wcs_to_celestial_frame, custom_wcs_to_frame_mappings
>>> with custom_wcs_to_frame_mappings(my_function):
... wcs_to_celestial_frame(...)
"""
for mapping_set in WCS_FRAME_MAPPINGS:
for func in mapping_set:
frame = func(wcs)
if frame is not None:
return frame
raise ValueError("Could not determine celestial frame corresponding to "
"the specified WCS object")
def celestial_frame_to_wcs(frame, projection='TAN'):
"""
For a given coordinate frame, return the corresponding WCS object.
Note that the returned WCS object has only the elements corresponding to
coordinate frames set (e.g. ctype, equinox, radesys).
Parameters
----------
frame : :class:`~astropy.coordinates.baseframe.BaseCoordinateFrame` subclass instance
An instance of a :class:`~astropy.coordinates.baseframe.BaseCoordinateFrame`
subclass instance for which to find the WCS
projection : str
Projection code to use in ctype, if applicable
Returns
-------
wcs : :class:`~astropy.wcs.WCS` instance
The corresponding WCS object
Examples
--------
::
>>> from astropy.wcs.utils import celestial_frame_to_wcs
>>> from astropy.coordinates import FK5
>>> frame = FK5(equinox='J2010')
>>> wcs = celestial_frame_to_wcs(frame)
>>> wcs.to_header()
WCSAXES = 2 / Number of coordinate axes
CRPIX1 = 0.0 / Pixel coordinate of reference point
CRPIX2 = 0.0 / Pixel coordinate of reference point
CDELT1 = 1.0 / [deg] Coordinate increment at reference point
CDELT2 = 1.0 / [deg] Coordinate increment at reference point
CUNIT1 = 'deg' / Units of coordinate increment and value
CUNIT2 = 'deg' / Units of coordinate increment and value
CTYPE1 = 'RA---TAN' / Right ascension, gnomonic projection
CTYPE2 = 'DEC--TAN' / Declination, gnomonic projection
CRVAL1 = 0.0 / [deg] Coordinate value at reference point
CRVAL2 = 0.0 / [deg] Coordinate value at reference point
LONPOLE = 180.0 / [deg] Native longitude of celestial pole
LATPOLE = 0.0 / [deg] Native latitude of celestial pole
RADESYS = 'FK5' / Equatorial coordinate system
EQUINOX = 2010.0 / [yr] Equinox of equatorial coordinates
Notes
-----
To extend this function to frames not defined in astropy.coordinates, you
can write your own function which should take a
:class:`~astropy.coordinates.baseframe.BaseCoordinateFrame` subclass
instance and a projection (given as a string) and should return either a WCS
instance, or `None` if the WCS could not be determined. You can register
this function temporarily with::
>>> from astropy.wcs.utils import celestial_frame_to_wcs, custom_frame_to_wcs_mappings
>>> with custom_frame_to_wcs_mappings(my_function):
... celestial_frame_to_wcs(...)
"""
for mapping_set in FRAME_WCS_MAPPINGS:
for func in mapping_set:
wcs = func(frame, projection=projection)
if wcs is not None:
return wcs
raise ValueError("Could not determine WCS corresponding to the specified "
"coordinate frame.")
def proj_plane_pixel_scales(wcs):
"""
For a WCS returns pixel scales along each axis of the image pixel at
the ``CRPIX`` location once it is projected onto the
"plane of intermediate world coordinates" as defined in
`Greisen & Calabretta 2002, A&A, 395, 1061 <http://adsabs.harvard.edu/abs/2002A%26A...395.1061G>`_.
.. note::
This function is concerned **only** about the transformation
"image plane"->"projection plane" and **not** about the
transformation "celestial sphere"->"projection plane"->"image plane".
Therefore, this function ignores distortions arising due to
non-linear nature of most projections.
.. note::
In order to compute the scales corresponding to celestial axes only,
make sure that the input `~astropy.wcs.WCS` object contains
celestial axes only, e.g., by passing in the
`~astropy.wcs.WCS.celestial` WCS object.
Parameters
----------
wcs : `~astropy.wcs.WCS`
A world coordinate system object.
Returns
-------
scale : `~numpy.ndarray`
A vector (`~numpy.ndarray`) of projection plane increments
corresponding to each pixel side (axis). The units of the returned
results are the same as the units of `~astropy.wcs.Wcsprm.cdelt`,
`~astropy.wcs.Wcsprm.crval`, and `~astropy.wcs.Wcsprm.cd` for
the celestial WCS and can be obtained by inquiring the value
of `~astropy.wcs.Wcsprm.cunit` property of the input
`~astropy.wcs.WCS` WCS object.
See Also
--------
astropy.wcs.utils.proj_plane_pixel_area
"""
return np.sqrt((wcs.pixel_scale_matrix**2).sum(axis=0, dtype=float))
def proj_plane_pixel_area(wcs):
"""
For a **celestial** WCS (see `astropy.wcs.WCS.celestial`) returns pixel
area of the image pixel at the ``CRPIX`` location once it is projected
onto the "plane of intermediate world coordinates" as defined in
`Greisen & Calabretta 2002, A&A, 395, 1061 <http://adsabs.harvard.edu/abs/2002A%26A...395.1061G>`_.
.. note::
This function is concerned **only** about the transformation
"image plane"->"projection plane" and **not** about the
transformation "celestial sphere"->"projection plane"->"image plane".
Therefore, this function ignores distortions arising due to
non-linear nature of most projections.
.. note::
In order to compute the area of pixels corresponding to celestial
axes only, this function uses the `~astropy.wcs.WCS.celestial` WCS
object of the input ``wcs``. This is different from the
`~astropy.wcs.utils.proj_plane_pixel_scales` function
that computes the scales for the axes of the input WCS itself.
Parameters
----------
wcs : `~astropy.wcs.WCS`
A world coordinate system object.
Returns
-------
area : float
Area (in the projection plane) of the pixel at ``CRPIX`` location.
The units of the returned result are the same as the units of
the `~astropy.wcs.Wcsprm.cdelt`, `~astropy.wcs.Wcsprm.crval`,
and `~astropy.wcs.Wcsprm.cd` for the celestial WCS and can be
obtained by inquiring the value of `~astropy.wcs.Wcsprm.cunit`
property of the `~astropy.wcs.WCS.celestial` WCS object.
Raises
------
ValueError
Pixel area is defined only for 2D pixels. Most likely the
`~astropy.wcs.Wcsprm.cd` matrix of the `~astropy.wcs.WCS.celestial`
WCS is not a square matrix of second order.
Notes
-----
Depending on the application, square root of the pixel area can be used to
represent a single pixel scale of an equivalent square pixel
whose area is equal to the area of a generally non-square pixel.
See Also
--------
astropy.wcs.utils.proj_plane_pixel_scales
"""
psm = wcs.celestial.pixel_scale_matrix
if psm.shape != (2, 2):
raise ValueError("Pixel area is defined only for 2D pixels.")
return np.abs(np.linalg.det(psm))
def is_proj_plane_distorted(wcs, maxerr=1.0e-5):
r"""
For a WCS returns `False` if square image (detector) pixels stay square
when projected onto the "plane of intermediate world coordinates"
as defined in
`Greisen & Calabretta 2002, A&A, 395, 1061 <http://adsabs.harvard.edu/abs/2002A%26A...395.1061G>`_.
It will return `True` if transformation from image (detector) coordinates
to the focal plane coordinates is non-orthogonal or if WCS contains
non-linear (e.g., SIP) distortions.
.. note::
Since this function is concerned **only** about the transformation
"image plane"->"focal plane" and **not** about the transformation
"celestial sphere"->"focal plane"->"image plane",
this function ignores distortions arising due to non-linear nature
of most projections.
Let's denote by *C* either the original or the reconstructed
(from ``PC`` and ``CDELT``) CD matrix. `is_proj_plane_distorted`
verifies that the transformation from image (detector) coordinates
to the focal plane coordinates is orthogonal using the following
check:
.. math::
\left \| \frac{C \cdot C^{\mathrm{T}}}
{| det(C)|} - I \right \|_{\mathrm{max}} < \epsilon .
Parameters
----------
wcs : `~astropy.wcs.WCS`
World coordinate system object
maxerr : float, optional
Accuracy to which the CD matrix, **normalized** such
that :math:`|det(CD)|=1`, should be close to being an
orthogonal matrix as described in the above equation
(see :math:`\epsilon`).
Returns
-------
distorted : bool
Returns `True` if focal (projection) plane is distorted and `False`
otherwise.
"""
cwcs = wcs.celestial
return (not _is_cd_orthogonal(cwcs.pixel_scale_matrix, maxerr) or
_has_distortion(cwcs))
def _is_cd_orthogonal(cd, maxerr):
shape = cd.shape
if not (len(shape) == 2 and shape[0] == shape[1]):
raise ValueError("CD (or PC) matrix must be a 2D square matrix.")
pixarea = np.abs(np.linalg.det(cd))
if (pixarea == 0.0):
raise ValueError("CD (or PC) matrix is singular.")
# NOTE: Technically, below we should use np.dot(cd, np.conjugate(cd.T))
# However, I am not aware of complex CD/PC matrices...
I = np.dot(cd, cd.T) / pixarea
cd_unitary_err = np.amax(np.abs(I - np.eye(shape[0])))
return (cd_unitary_err < maxerr)
def non_celestial_pixel_scales(inwcs):
"""
Calculate the pixel scale along each axis of a non-celestial WCS,
for example one with mixed spectral and spatial axes.
Parameters
----------
inwcs : `~astropy.wcs.WCS`
The world coordinate system object.
Returns
-------
scale : `numpy.ndarray`
The pixel scale along each axis.
"""
if inwcs.is_celestial:
raise ValueError("WCS is celestial, use celestial_pixel_scales instead")
pccd = inwcs.pixel_scale_matrix
if np.allclose(np.extract(1-np.eye(*pccd.shape), pccd), 0):
return np.abs(np.diagonal(pccd))*u.deg
else:
raise ValueError("WCS is rotated, cannot determine consistent pixel scales")
def _has_distortion(wcs):
"""
`True` if contains any SIP or image distortion components.
"""
return any(getattr(wcs, dist_attr) is not None
for dist_attr in ['cpdis1', 'cpdis2', 'det2im1', 'det2im2', 'sip'])
# TODO: in future, we should think about how the following two functions can be
# integrated better into the WCS class.
def skycoord_to_pixel(coords, wcs, origin=0, mode='all'):
"""
Convert a set of SkyCoord coordinates into pixels.
Parameters
----------
coords : `~astropy.coordinates.SkyCoord`
The coordinates to convert.
wcs : `~astropy.wcs.WCS`
The WCS transformation to use.
origin : int
Whether to return 0 or 1-based pixel coordinates.
mode : 'all' or 'wcs'
Whether to do the transformation including distortions (``'all'``) or
only including only the core WCS transformation (``'wcs'``).
Returns
-------
xp, yp : `numpy.ndarray`
The pixel coordinates
See Also
--------
astropy.coordinates.SkyCoord.from_pixel
"""
if _has_distortion(wcs) and wcs.naxis != 2:
raise ValueError("Can only handle WCS with distortions for 2-dimensional WCS")
# Keep only the celestial part of the axes, also re-orders lon/lat
wcs = wcs.sub([WCSSUB_CELESTIAL])
if wcs.naxis != 2:
raise ValueError("WCS should contain celestial component")
# Check which frame the WCS uses
frame = wcs_to_celestial_frame(wcs)
# Check what unit the WCS needs
xw_unit = u.Unit(wcs.wcs.cunit[0])
yw_unit = u.Unit(wcs.wcs.cunit[1])
# Convert positions to frame
coords = coords.transform_to(frame)
# Extract longitude and latitude. We first try and use lon/lat directly,
# but if the representation is not spherical or unit spherical this will
# fail. We should then force the use of the unit spherical
# representation. We don't do that directly to make sure that we preserve
# custom lon/lat representations if available.
try:
lon = coords.data.lon.to(xw_unit)
lat = coords.data.lat.to(yw_unit)
except AttributeError:
lon = coords.spherical.lon.to(xw_unit)
lat = coords.spherical.lat.to(yw_unit)
# Convert to pixel coordinates
if mode == 'all':
xp, yp = wcs.all_world2pix(lon.value, lat.value, origin)
elif mode == 'wcs':
xp, yp = wcs.wcs_world2pix(lon.value, lat.value, origin)
else:
raise ValueError("mode should be either 'all' or 'wcs'")
return xp, yp
def pixel_to_skycoord(xp, yp, wcs, origin=0, mode='all', cls=None):
"""
Convert a set of pixel coordinates into a `~astropy.coordinates.SkyCoord`
coordinate.
Parameters
----------
xp, yp : float or `numpy.ndarray`
The coordinates to convert.
wcs : `~astropy.wcs.WCS`
The WCS transformation to use.
origin : int
Whether to return 0 or 1-based pixel coordinates.
mode : 'all' or 'wcs'
Whether to do the transformation including distortions (``'all'``) or
only including only the core WCS transformation (``'wcs'``).
cls : class or None
The class of object to create. Should be a
`~astropy.coordinates.SkyCoord` subclass. If None, defaults to
`~astropy.coordinates.SkyCoord`.
Returns
-------
coords : Whatever ``cls`` is (a subclass of `~astropy.coordinates.SkyCoord`)
The celestial coordinates
See Also
--------
astropy.coordinates.SkyCoord.from_pixel
"""
# Import astropy.coordinates here to avoid circular imports
from ..coordinates import SkyCoord, UnitSphericalRepresentation
# we have to do this instead of actually setting the default to SkyCoord
# because importing SkyCoord at the module-level leads to circular
# dependencies.
if cls is None:
cls = SkyCoord
if _has_distortion(wcs) and wcs.naxis != 2:
raise ValueError("Can only handle WCS with distortions for 2-dimensional WCS")
# Keep only the celestial part of the axes, also re-orders lon/lat
wcs = wcs.sub([WCSSUB_CELESTIAL])
if wcs.naxis != 2:
raise ValueError("WCS should contain celestial component")
# Check which frame the WCS uses
frame = wcs_to_celestial_frame(wcs)
# Check what unit the WCS gives
lon_unit = u.Unit(wcs.wcs.cunit[0])
lat_unit = u.Unit(wcs.wcs.cunit[1])
# Convert pixel coordinates to celestial coordinates
if mode == 'all':
lon, lat = wcs.all_pix2world(xp, yp, origin)
elif mode == 'wcs':
lon, lat = wcs.wcs_pix2world(xp, yp, origin)
else:
raise ValueError("mode should be either 'all' or 'wcs'")
# Add units to longitude/latitude
lon = lon * lon_unit
lat = lat * lat_unit
# Create a SkyCoord-like object
data = UnitSphericalRepresentation(lon=lon, lat=lat)
coords = cls(frame.realize_frame(data))
return coords
|
687f6500bb8853d61bfd95e99f92cacccb159e218af3efc6e1dadca5283b5622 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Under the hood, there are 3 separate classes that perform different
parts of the transformation:
- `~astropy.wcs.Wcsprm`: Is a direct wrapper of the core WCS
functionality in `wcslib`_. (This includes TPV and TPD
polynomial distortion, but not SIP distortion).
- `~astropy.wcs.Sip`: Handles polynomial distortion as defined in the
`SIP`_ convention.
- `~astropy.wcs.DistortionLookupTable`: Handles `distortion paper`_
lookup tables.
Additionally, the class `WCS` aggregates all of these transformations
together in a pipeline:
- Detector to image plane correction (by a pair of
`~astropy.wcs.DistortionLookupTable` objects).
- `SIP`_ distortion correction (by an underlying `~astropy.wcs.Sip`
object)
- `distortion paper`_ table-lookup correction (by a pair of
`~astropy.wcs.DistortionLookupTable` objects).
- `wcslib`_ WCS transformation (by a `~astropy.wcs.Wcsprm` object)
"""
# STDLIB
import copy
import io
import itertools
import os
import re
import textwrap
import warnings
import builtins
# THIRD-PARTY
import numpy as np
# LOCAL
from .. import log
from ..io import fits
from . import _docutil as __
try:
from . import _wcs
except ImportError:
if not _ASTROPY_SETUP_:
raise
else:
_wcs = None
from ..utils.compat import possible_filename
from ..utils.exceptions import AstropyWarning, AstropyUserWarning, AstropyDeprecationWarning
__all__ = ['FITSFixedWarning', 'WCS', 'find_all_wcs',
'DistortionLookupTable', 'Sip', 'Tabprm', 'Wcsprm',
'WCSBase', 'validate', 'WcsError', 'SingularMatrixError',
'InconsistentAxisTypesError', 'InvalidTransformError',
'InvalidCoordinateError', 'NoSolutionError',
'InvalidSubimageSpecificationError', 'NoConvergence',
'NonseparableSubimageCoordinateSystemError',
'NoWcsKeywordsFoundError', 'InvalidTabularParametersError']
__doctest_skip__ = ['WCS.all_world2pix']
if _wcs is not None:
_parsed_version = _wcs.__version__.split('.')
if int(_parsed_version[0]) == 5 and int(_parsed_version[1]) < 8:
raise ImportError(
"astropy.wcs is built with wcslib {0}, but only versions 5.8 and "
"later on the 5.x series are known to work. The version of wcslib "
"that ships with astropy may be used.")
if not _wcs._sanity_check():
raise RuntimeError(
"astropy.wcs did not pass its sanity check for your build "
"on your platform.")
WCSBase = _wcs._Wcs
DistortionLookupTable = _wcs.DistortionLookupTable
Sip = _wcs.Sip
Wcsprm = _wcs.Wcsprm
Tabprm = _wcs.Tabprm
WcsError = _wcs.WcsError
SingularMatrixError = _wcs.SingularMatrixError
InconsistentAxisTypesError = _wcs.InconsistentAxisTypesError
InvalidTransformError = _wcs.InvalidTransformError
InvalidCoordinateError = _wcs.InvalidCoordinateError
NoSolutionError = _wcs.NoSolutionError
InvalidSubimageSpecificationError = _wcs.InvalidSubimageSpecificationError
NonseparableSubimageCoordinateSystemError = _wcs.NonseparableSubimageCoordinateSystemError
NoWcsKeywordsFoundError = _wcs.NoWcsKeywordsFoundError
InvalidTabularParametersError = _wcs.InvalidTabularParametersError
# Copy all the constants from the C extension into this module's namespace
for key, val in _wcs.__dict__.items():
if key.startswith(('WCSSUB', 'WCSHDR', 'WCSHDO')):
locals()[key] = val
__all__.append(key)
else:
WCSBase = object
Wcsprm = object
DistortionLookupTable = object
Sip = object
Tabprm = object
WcsError = None
SingularMatrixError = None
InconsistentAxisTypesError = None
InvalidTransformError = None
InvalidCoordinateError = None
NoSolutionError = None
InvalidSubimageSpecificationError = None
NonseparableSubimageCoordinateSystemError = None
NoWcsKeywordsFoundError = None
InvalidTabularParametersError = None
# Additional relax bit flags
WCSHDO_SIP = 0x80000
# Regular expression defining SIP keyword It matches keyword that starts with A
# or B, optionally followed by P, followed by an underscore then a number in
# range of 0-19, followed by an underscore and another number in range of 0-19.
# Keyword optionally ends with a capital letter.
SIP_KW = re.compile('''^[AB]P?_1?[0-9]_1?[0-9][A-Z]?$''')
def _parse_keysel(keysel):
keysel_flags = 0
if keysel is not None:
for element in keysel:
if element.lower() == 'image':
keysel_flags |= _wcs.WCSHDR_IMGHEAD
elif element.lower() == 'binary':
keysel_flags |= _wcs.WCSHDR_BIMGARR
elif element.lower() == 'pixel':
keysel_flags |= _wcs.WCSHDR_PIXLIST
else:
raise ValueError(
"keysel must be a list of 'image', 'binary' " +
"and/or 'pixel'")
else:
keysel_flags = -1
return keysel_flags
class NoConvergence(Exception):
"""
An error class used to report non-convergence and/or divergence
of numerical methods. It is used to report errors in the
iterative solution used by
the :py:meth:`~astropy.wcs.WCS.all_world2pix`.
Attributes
----------
best_solution : `numpy.ndarray`
Best solution achieved by the numerical method.
accuracy : `numpy.ndarray`
Accuracy of the ``best_solution``.
niter : `int`
Number of iterations performed by the numerical method
to compute ``best_solution``.
divergent : None, `numpy.ndarray`
Indices of the points in ``best_solution`` array
for which the solution appears to be divergent. If the
solution does not diverge, ``divergent`` will be set to `None`.
slow_conv : None, `numpy.ndarray`
Indices of the solutions in ``best_solution`` array
for which the solution failed to converge within the
specified maximum number of iterations. If there are no
non-converging solutions (i.e., if the required accuracy
has been achieved for all input data points)
then ``slow_conv`` will be set to `None`.
"""
def __init__(self, *args, best_solution=None, accuracy=None, niter=None,
divergent=None, slow_conv=None, **kwargs):
super().__init__(*args)
self.best_solution = best_solution
self.accuracy = accuracy
self.niter = niter
self.divergent = divergent
self.slow_conv = slow_conv
if kwargs:
warnings.warn("Function received unexpected arguments ({}) these "
"are ignored but will raise an Exception in the "
"future.".format(list(kwargs)),
AstropyDeprecationWarning)
class FITSFixedWarning(AstropyWarning):
"""
The warning raised when the contents of the FITS header have been
modified to be standards compliant.
"""
pass
class WCS(WCSBase):
"""WCS objects perform standard WCS transformations, and correct for
`SIP`_ and `distortion paper`_ table-lookup transformations, based
on the WCS keywords and supplementary data read from a FITS file.
Parameters
----------
header : astropy.io.fits header object, Primary HDU, Image HDU, string, dict-like, or None, optional
If *header* is not provided or None, the object will be
initialized to default values.
fobj : An astropy.io.fits file (hdulist) object, optional
It is needed when header keywords point to a `distortion
paper`_ lookup table stored in a different extension.
key : str, optional
The name of a particular WCS transform to use. This may be
either ``' '`` or ``'A'``-``'Z'`` and corresponds to the
``\"a\"`` part of the ``CTYPEia`` cards. *key* may only be
provided if *header* is also provided.
minerr : float, optional
The minimum value a distortion correction must have in order
to be applied. If the value of ``CQERRja`` is smaller than
*minerr*, the corresponding distortion is not applied.
relax : bool or int, optional
Degree of permissiveness:
- `True` (default): Admit all recognized informal extensions
of the WCS standard.
- `False`: Recognize only FITS keywords defined by the
published WCS standard.
- `int`: a bit field selecting specific extensions to accept.
See :ref:`relaxread` for details.
naxis : int or sequence, optional
Extracts specific coordinate axes using
:meth:`~astropy.wcs.Wcsprm.sub`. If a header is provided, and
*naxis* is not ``None``, *naxis* will be passed to
:meth:`~astropy.wcs.Wcsprm.sub` in order to select specific
axes from the header. See :meth:`~astropy.wcs.Wcsprm.sub` for
more details about this parameter.
keysel : sequence of flags, optional
A sequence of flags used to select the keyword types
considered by wcslib. When ``None``, only the standard image
header keywords are considered (and the underlying wcspih() C
function is called). To use binary table image array or pixel
list keywords, *keysel* must be set.
Each element in the list should be one of the following
strings:
- 'image': Image header keywords
- 'binary': Binary table image array keywords
- 'pixel': Pixel list keywords
Keywords such as ``EQUIna`` or ``RFRQna`` that are common to
binary table image arrays and pixel lists (including
``WCSNna`` and ``TWCSna``) are selected by both 'binary' and
'pixel'.
colsel : sequence of int, optional
A sequence of table column numbers used to restrict the WCS
transformations considered to only those pertaining to the
specified columns. If `None`, there is no restriction.
fix : bool, optional
When `True` (default), call `~astropy.wcs.Wcsprm.fix` on
the resulting object to fix any non-standard uses in the
header. `FITSFixedWarning` Warnings will be emitted if any
changes were made.
translate_units : str, optional
Specify which potentially unsafe translations of non-standard
unit strings to perform. By default, performs none. See
`WCS.fix` for more information about this parameter. Only
effective when ``fix`` is `True`.
Raises
------
MemoryError
Memory allocation failed.
ValueError
Invalid key.
KeyError
Key not found in FITS header.
ValueError
Lookup table distortion present in the header but *fobj* was
not provided.
Notes
-----
1. astropy.wcs supports arbitrary *n* dimensions for the core WCS
(the transformations handled by WCSLIB). However, the
`distortion paper`_ lookup table and `SIP`_ distortions must be
two dimensional. Therefore, if you try to create a WCS object
where the core WCS has a different number of dimensions than 2
and that object also contains a `distortion paper`_ lookup
table or `SIP`_ distortion, a `ValueError`
exception will be raised. To avoid this, consider using the
*naxis* kwarg to select two dimensions from the core WCS.
2. The number of coordinate axes in the transformation is not
determined directly from the ``NAXIS`` keyword but instead from
the highest of:
- ``NAXIS`` keyword
- ``WCSAXESa`` keyword
- The highest axis number in any parameterized WCS keyword.
The keyvalue, as well as the keyword, must be
syntactically valid otherwise it will not be considered.
If none of these keyword types is present, i.e. if the header
only contains auxiliary WCS keywords for a particular
coordinate representation, then no coordinate description is
constructed for it.
The number of axes, which is set as the ``naxis`` member, may
differ for different coordinate representations of the same
image.
3. When the header includes duplicate keywords, in most cases the
last encountered is used.
4. `~astropy.wcs.Wcsprm.set` is called immediately after
construction, so any invalid keywords or transformations will
be raised by the constructor, not when subsequently calling a
transformation method.
"""
def __init__(self, header=None, fobj=None, key=' ', minerr=0.0,
relax=True, naxis=None, keysel=None, colsel=None,
fix=True, translate_units='', _do_set=True):
close_fds = []
if header is None:
if naxis is None:
naxis = 2
wcsprm = _wcs.Wcsprm(header=None, key=key,
relax=relax, naxis=naxis)
self.naxis = wcsprm.naxis
# Set some reasonable defaults.
det2im = (None, None)
cpdis = (None, None)
sip = None
else:
keysel_flags = _parse_keysel(keysel)
if isinstance(header, (str, bytes)):
try:
is_path = (possible_filename(header) and
os.path.exists(header))
except (OSError, ValueError):
is_path = False
if is_path:
if fobj is not None:
raise ValueError(
"Can not provide both a FITS filename to "
"argument 1 and a FITS file object to argument 2")
fobj = fits.open(header)
close_fds.append(fobj)
header = fobj[0].header
elif isinstance(header, fits.hdu.image._ImageBaseHDU):
header = header.header
elif not isinstance(header, fits.Header):
try:
# Accept any dict-like object
orig_header = header
header = fits.Header()
for dict_key in orig_header.keys():
header[dict_key] = orig_header[dict_key]
except TypeError:
raise TypeError(
"header must be a string, an astropy.io.fits.Header "
"object, or a dict-like object")
if isinstance(header, fits.Header):
header_string = header.tostring().rstrip()
else:
header_string = header
# Importantly, header is a *copy* of the passed-in header
# because we will be modifying it
if isinstance(header_string, str):
header_bytes = header_string.encode('ascii')
header_string = header_string
else:
header_bytes = header_string
header_string = header_string.decode('ascii')
try:
tmp_header = fits.Header.fromstring(header_string)
self._remove_sip_kw(tmp_header)
tmp_header_bytes = tmp_header.tostring().rstrip()
if isinstance(tmp_header_bytes, str):
tmp_header_bytes = tmp_header_bytes.encode('ascii')
tmp_wcsprm = _wcs.Wcsprm(header=tmp_header_bytes, key=key,
relax=relax, keysel=keysel_flags,
colsel=colsel, warnings=False)
except _wcs.NoWcsKeywordsFoundError:
est_naxis = 0
else:
if naxis is not None:
try:
tmp_wcsprm.sub(naxis)
except ValueError:
pass
est_naxis = tmp_wcsprm.naxis
else:
est_naxis = 2
header = fits.Header.fromstring(header_string)
if est_naxis == 0:
est_naxis = 2
self.naxis = est_naxis
det2im = self._read_det2im_kw(header, fobj, err=minerr)
cpdis = self._read_distortion_kw(
header, fobj, dist='CPDIS', err=minerr)
sip = self._read_sip_kw(header, wcskey=key)
self._remove_sip_kw(header)
header_string = header.tostring()
header_string = header_string.replace('END' + ' ' * 77, '')
if isinstance(header_string, str):
header_bytes = header_string.encode('ascii')
header_string = header_string
else:
header_bytes = header_string
header_string = header_string.decode('ascii')
try:
wcsprm = _wcs.Wcsprm(header=header_bytes, key=key,
relax=relax, keysel=keysel_flags,
colsel=colsel)
except _wcs.NoWcsKeywordsFoundError:
# The header may have SIP or distortions, but no core
# WCS. That isn't an error -- we want a "default"
# (identity) core Wcs transformation in that case.
if colsel is None:
wcsprm = _wcs.Wcsprm(header=None, key=key,
relax=relax, keysel=keysel_flags,
colsel=colsel)
else:
raise
if naxis is not None:
wcsprm = wcsprm.sub(naxis)
self.naxis = wcsprm.naxis
if (wcsprm.naxis != 2 and
(det2im[0] or det2im[1] or cpdis[0] or cpdis[1] or sip)):
raise ValueError(
"""
FITS WCS distortion paper lookup tables and SIP distortions only work
in 2 dimensions. However, WCSLIB has detected {0} dimensions in the
core WCS keywords. To use core WCS in conjunction with FITS WCS
distortion paper lookup tables or SIP distortion, you must select or
reduce these to 2 dimensions using the naxis kwarg.
""".format(wcsprm.naxis))
header_naxis = header.get('NAXIS', None)
if header_naxis is not None and header_naxis < wcsprm.naxis:
warnings.warn(
"The WCS transformation has more axes ({0:d}) than the "
"image it is associated with ({1:d})".format(
wcsprm.naxis, header_naxis), FITSFixedWarning)
self._get_naxis(header)
WCSBase.__init__(self, sip, cpdis, wcsprm, det2im)
if fix:
self.fix(translate_units=translate_units)
if _do_set:
self.wcs.set()
for fd in close_fds:
fd.close()
def __copy__(self):
new_copy = self.__class__()
WCSBase.__init__(new_copy, self.sip,
(self.cpdis1, self.cpdis2),
self.wcs,
(self.det2im1, self.det2im2))
new_copy.__dict__.update(self.__dict__)
return new_copy
def __deepcopy__(self, memo):
from copy import deepcopy
new_copy = self.__class__()
new_copy.naxis = deepcopy(self.naxis, memo)
WCSBase.__init__(new_copy, deepcopy(self.sip, memo),
(deepcopy(self.cpdis1, memo),
deepcopy(self.cpdis2, memo)),
deepcopy(self.wcs, memo),
(deepcopy(self.det2im1, memo),
deepcopy(self.det2im2, memo)))
for key, val in self.__dict__.items():
new_copy.__dict__[key] = deepcopy(val, memo)
return new_copy
def copy(self):
"""
Return a shallow copy of the object.
Convenience method so user doesn't have to import the
:mod:`copy` stdlib module.
.. warning::
Use `deepcopy` instead of `copy` unless you know why you need a
shallow copy.
"""
return copy.copy(self)
def deepcopy(self):
"""
Return a deep copy of the object.
Convenience method so user doesn't have to import the
:mod:`copy` stdlib module.
"""
return copy.deepcopy(self)
def sub(self, axes=None):
copy = self.deepcopy()
copy.wcs = self.wcs.sub(axes)
copy.naxis = copy.wcs.naxis
return copy
if _wcs is not None:
sub.__doc__ = _wcs.Wcsprm.sub.__doc__
def _fix_scamp(self):
"""
Remove SCAMP's PVi_m distortion parameters if SIP distortion parameters
are also present. Some projects (e.g., Palomar Transient Factory)
convert SCAMP's distortion parameters (which abuse the PVi_m cards) to
SIP. However, wcslib gets confused by the presence of both SCAMP and
SIP distortion parameters.
See https://github.com/astropy/astropy/issues/299.
"""
# Nothing to be done if no WCS attached
if self.wcs is None:
return
# Nothing to be done if no PV parameters attached
pv = self.wcs.get_pv()
if not pv:
return
# Nothing to be done if axes don't use SIP distortion parameters
if self.sip is None:
return
# Nothing to be done if any radial terms are present...
# Loop over list to find any radial terms.
# Certain values of the `j' index are used for storing
# radial terms; refer to Equation (1) in
# <http://web.ipac.caltech.edu/staff/shupe/reprints/SIP_to_PV_SPIE2012.pdf>.
pv = np.asarray(pv)
# Loop over distinct values of `i' index
for i in set(pv[:, 0]):
# Get all values of `j' index for this value of `i' index
js = set(pv[:, 1][pv[:, 0] == i])
# Find max value of `j' index
max_j = max(js)
for j in (3, 11, 23, 39):
if j < max_j and j in js:
return
self.wcs.set_pv([])
warnings.warn("Removed redundant SCAMP distortion parameters " +
"because SIP parameters are also present", FITSFixedWarning)
def fix(self, translate_units='', naxis=None):
"""
Perform the fix operations from wcslib, and warn about any
changes it has made.
Parameters
----------
translate_units : str, optional
Specify which potentially unsafe translations of
non-standard unit strings to perform. By default,
performs none.
Although ``"S"`` is commonly used to represent seconds,
its translation to ``"s"`` is potentially unsafe since the
standard recognizes ``"S"`` formally as Siemens, however
rarely that may be used. The same applies to ``"H"`` for
hours (Henry), and ``"D"`` for days (Debye).
This string controls what to do in such cases, and is
case-insensitive.
- If the string contains ``"s"``, translate ``"S"`` to
``"s"``.
- If the string contains ``"h"``, translate ``"H"`` to
``"h"``.
- If the string contains ``"d"``, translate ``"D"`` to
``"d"``.
Thus ``''`` doesn't do any unsafe translations, whereas
``'shd'`` does all of them.
naxis : int array[naxis], optional
Image axis lengths. If this array is set to zero or
``None``, then `~astropy.wcs.Wcsprm.cylfix` will not be
invoked.
"""
if self.wcs is not None:
self._fix_scamp()
fixes = self.wcs.fix(translate_units, naxis)
for key, val in fixes.items():
if val != "No change":
warnings.warn(
("'{0}' made the change '{1}'.").
format(key, val),
FITSFixedWarning)
def calc_footprint(self, header=None, undistort=True, axes=None, center=True):
"""
Calculates the footprint of the image on the sky.
A footprint is defined as the positions of the corners of the
image on the sky after all available distortions have been
applied.
Parameters
----------
header : `~astropy.io.fits.Header` object, optional
Used to get ``NAXIS1`` and ``NAXIS2``
header and axes are mutually exclusive, alternative ways
to provide the same information.
undistort : bool, optional
If `True`, take SIP and distortion lookup table into
account
axes : length 2 sequence ints, optional
If provided, use the given sequence as the shape of the
image. Otherwise, use the ``NAXIS1`` and ``NAXIS2``
keywords from the header that was used to create this
`WCS` object.
center : bool, optional
If `True` use the center of the pixel, otherwise use the corner.
Returns
-------
coord : (4, 2) array of (*x*, *y*) coordinates.
The order is clockwise starting with the bottom left corner.
"""
if axes is not None:
naxis1, naxis2 = axes
else:
if header is None:
try:
# classes that inherit from WCS and define naxis1/2
# do not require a header parameter
naxis1 = self._naxis1
naxis2 = self._naxis2
except AttributeError:
warnings.warn("Need a valid header in order to calculate footprint\n", AstropyUserWarning)
return None
else:
naxis1 = header.get('NAXIS1', None)
naxis2 = header.get('NAXIS2', None)
if naxis1 is None or naxis2 is None:
raise ValueError(
"Image size could not be determined.")
if center:
corners = np.array([[1, 1],
[1, naxis2],
[naxis1, naxis2],
[naxis1, 1]], dtype=np.float64)
else:
corners = np.array([[0.5, 0.5],
[0.5, naxis2 + 0.5],
[naxis1 + 0.5, naxis2 + 0.5],
[naxis1 + 0.5, 0.5]], dtype=np.float64)
if undistort:
return self.all_pix2world(corners, 1)
else:
return self.wcs_pix2world(corners, 1)
def _read_det2im_kw(self, header, fobj, err=0.0):
"""
Create a `distortion paper`_ type lookup table for detector to
image plane correction.
"""
if fobj is None:
return (None, None)
if not isinstance(fobj, fits.HDUList):
return (None, None)
try:
axiscorr = header[str('AXISCORR')]
d2imdis = self._read_d2im_old_format(header, fobj, axiscorr)
return d2imdis
except KeyError:
pass
dist = 'D2IMDIS'
d_kw = 'D2IM'
err_kw = 'D2IMERR'
tables = {}
for i in range(1, self.naxis + 1):
d_error = header.get(err_kw + str(i), 0.0)
if d_error < err:
tables[i] = None
continue
distortion = dist + str(i)
if distortion in header:
dis = header[distortion].lower()
if dis == 'lookup':
del header[distortion]
assert isinstance(fobj, fits.HDUList), ('An astropy.io.fits.HDUList'
'is required for Lookup table distortion.')
dp = (d_kw + str(i)).strip()
dp_extver_key = dp + str('.EXTVER')
if dp_extver_key in header:
d_extver = header[dp_extver_key]
del header[dp_extver_key]
else:
d_extver = 1
dp_axis_key = dp + str('.AXIS.{0:d}').format(i)
if i == header[dp_axis_key]:
d_data = fobj[str('D2IMARR'), d_extver].data
else:
d_data = (fobj[str('D2IMARR'), d_extver].data).transpose()
del header[dp_axis_key]
d_header = fobj[str('D2IMARR'), d_extver].header
d_crpix = (d_header.get(str('CRPIX1'), 0.0), d_header.get(str('CRPIX2'), 0.0))
d_crval = (d_header.get(str('CRVAL1'), 0.0), d_header.get(str('CRVAL2'), 0.0))
d_cdelt = (d_header.get(str('CDELT1'), 1.0), d_header.get(str('CDELT2'), 1.0))
d_lookup = DistortionLookupTable(d_data, d_crpix,
d_crval, d_cdelt)
tables[i] = d_lookup
else:
warnings.warn('Polynomial distortion is not implemented.\n', AstropyUserWarning)
for key in list(header):
if key.startswith(dp + str('.')):
del header[key]
else:
tables[i] = None
if not tables:
return (None, None)
else:
return (tables.get(1), tables.get(2))
def _read_d2im_old_format(self, header, fobj, axiscorr):
warnings.warn("The use of ``AXISCORR`` for D2IM correction has been deprecated."
"`~astropy.wcs` will read in files with ``AXISCORR`` but ``to_fits()`` will write "
"out files without it.",
AstropyDeprecationWarning)
cpdis = [None, None]
crpix = [0., 0.]
crval = [0., 0.]
cdelt = [1., 1.]
try:
d2im_data = fobj[(str('D2IMARR'), 1)].data
except KeyError:
return (None, None)
except AttributeError:
return (None, None)
d2im_data = np.array([d2im_data])
d2im_hdr = fobj[(str('D2IMARR'), 1)].header
naxis = d2im_hdr[str('NAXIS')]
for i in range(1, naxis + 1):
crpix[i - 1] = d2im_hdr.get(str('CRPIX') + str(i), 0.0)
crval[i - 1] = d2im_hdr.get(str('CRVAL') + str(i), 0.0)
cdelt[i - 1] = d2im_hdr.get(str('CDELT') + str(i), 1.0)
cpdis = DistortionLookupTable(d2im_data, crpix, crval, cdelt)
if axiscorr == 1:
return (cpdis, None)
elif axiscorr == 2:
return (None, cpdis)
else:
warnings.warn("Expected AXISCORR to be 1 or 2", AstropyUserWarning)
return (None, None)
def _write_det2im(self, hdulist):
"""
Writes a `distortion paper`_ type lookup table to the given
`astropy.io.fits.HDUList`.
"""
if self.det2im1 is None and self.det2im2 is None:
return
dist = 'D2IMDIS'
d_kw = 'D2IM'
err_kw = 'D2IMERR'
def write_d2i(num, det2im):
if det2im is None:
return
str('{0}{1:d}').format(dist, num),
hdulist[0].header[str('{0}{1:d}').format(dist, num)] = (
'LOOKUP', 'Detector to image correction type')
hdulist[0].header[str('{0}{1:d}.EXTVER').format(d_kw, num)] = (
num, 'Version number of WCSDVARR extension')
hdulist[0].header[str('{0}{1:d}.NAXES').format(d_kw, num)] = (
len(det2im.data.shape), 'Number of independent variables in d2im function')
for i in range(det2im.data.ndim):
hdulist[0].header[str('{0}{1:d}.AXIS.{2:d}').format(d_kw, num, i + 1)] = (
i + 1, 'Axis number of the jth independent variable in a d2im function')
image = fits.ImageHDU(det2im.data, name=str('D2IMARR'))
header = image.header
header[str('CRPIX1')] = (det2im.crpix[0],
'Coordinate system reference pixel')
header[str('CRPIX2')] = (det2im.crpix[1],
'Coordinate system reference pixel')
header[str('CRVAL1')] = (det2im.crval[0],
'Coordinate system value at reference pixel')
header[str('CRVAL2')] = (det2im.crval[1],
'Coordinate system value at reference pixel')
header[str('CDELT1')] = (det2im.cdelt[0],
'Coordinate increment along axis')
header[str('CDELT2')] = (det2im.cdelt[1],
'Coordinate increment along axis')
image.ver = int(hdulist[0].header[str('{0}{1:d}.EXTVER').format(d_kw, num)])
hdulist.append(image)
write_d2i(1, self.det2im1)
write_d2i(2, self.det2im2)
def _read_distortion_kw(self, header, fobj, dist='CPDIS', err=0.0):
"""
Reads `distortion paper`_ table-lookup keywords and data, and
returns a 2-tuple of `~astropy.wcs.DistortionLookupTable`
objects.
If no `distortion paper`_ keywords are found, ``(None, None)``
is returned.
"""
if isinstance(header, (str, bytes)):
return (None, None)
if dist == 'CPDIS':
d_kw = str('DP')
err_kw = str('CPERR')
else:
d_kw = str('DQ')
err_kw = str('CQERR')
tables = {}
for i in range(1, self.naxis + 1):
d_error_key = err_kw + str(i)
if d_error_key in header:
d_error = header[d_error_key]
del header[d_error_key]
else:
d_error = 0.0
if d_error < err:
tables[i] = None
continue
distortion = dist + str(i)
if distortion in header:
dis = header[distortion].lower()
del header[distortion]
if dis == 'lookup':
if not isinstance(fobj, fits.HDUList):
raise ValueError('an astropy.io.fits.HDUList is '
'required for Lookup table distortion.')
dp = (d_kw + str(i)).strip()
dp_extver_key = dp + str('.EXTVER')
if dp_extver_key in header:
d_extver = header[dp_extver_key]
del header[dp_extver_key]
else:
d_extver = 1
dp_axis_key = dp + str('.AXIS.{0:d}'.format(i))
if i == header[dp_axis_key]:
d_data = fobj[str('WCSDVARR'), d_extver].data
else:
d_data = (fobj[str('WCSDVARR'), d_extver].data).transpose()
del header[dp_axis_key]
d_header = fobj[str('WCSDVARR'), d_extver].header
d_crpix = (d_header.get(str('CRPIX1'), 0.0),
d_header.get(str('CRPIX2'), 0.0))
d_crval = (d_header.get(str('CRVAL1'), 0.0),
d_header.get(str('CRVAL2'), 0.0))
d_cdelt = (d_header.get(str('CDELT1'), 1.0),
d_header.get(str('CDELT2'), 1.0))
d_lookup = DistortionLookupTable(d_data, d_crpix, d_crval, d_cdelt)
tables[i] = d_lookup
for key in list(header):
if key.startswith(dp + str('.')):
del header[key]
else:
warnings.warn('Polynomial distortion is not implemented.\n', AstropyUserWarning)
else:
tables[i] = None
if not tables:
return (None, None)
else:
return (tables.get(1), tables.get(2))
def _write_distortion_kw(self, hdulist, dist='CPDIS'):
"""
Write out `distortion paper`_ keywords to the given
`fits.HDUList`.
"""
if self.cpdis1 is None and self.cpdis2 is None:
return
if dist == 'CPDIS':
d_kw = str('DP')
err_kw = str('CPERR')
else:
d_kw = str('DQ')
err_kw = str('CQERR')
def write_dist(num, cpdis):
if cpdis is None:
return
hdulist[0].header[str('{0}{1:d}').format(dist, num)] = (
'LOOKUP', 'Prior distortion function type')
hdulist[0].header[str('{0}{1:d}.EXTVER').format(d_kw, num)] = (
num, 'Version number of WCSDVARR extension')
hdulist[0].header[str('{0}{1:d}.NAXES').format(d_kw, num)] = (
len(cpdis.data.shape), 'Number of independent variables in distortion function')
for i in range(cpdis.data.ndim):
hdulist[0].header[str('{0}{1:d}.AXIS.{2:d}').format(d_kw, num, i + 1)] = (
i + 1,
'Axis number of the jth independent variable in a distortion function')
image = fits.ImageHDU(cpdis.data, name=str('WCSDVARR'))
header = image.header
header[str('CRPIX1')] = (cpdis.crpix[0], 'Coordinate system reference pixel')
header[str('CRPIX2')] = (cpdis.crpix[1], 'Coordinate system reference pixel')
header[str('CRVAL1')] = (cpdis.crval[0], 'Coordinate system value at reference pixel')
header[str('CRVAL2')] = (cpdis.crval[1], 'Coordinate system value at reference pixel')
header[str('CDELT1')] = (cpdis.cdelt[0], 'Coordinate increment along axis')
header[str('CDELT2')] = (cpdis.cdelt[1], 'Coordinate increment along axis')
image.ver = int(hdulist[0].header[str('{0}{1:d}.EXTVER').format(d_kw, num)])
hdulist.append(image)
write_dist(1, self.cpdis1)
write_dist(2, self.cpdis2)
def _remove_sip_kw(self, header):
"""
Remove SIP information from a header.
"""
# Never pass SIP coefficients to wcslib
# CTYPE must be passed with -SIP to wcslib
for key in (m.group() for m in map(SIP_KW.match, list(header))
if m is not None):
del header[key]
def _read_sip_kw(self, header, wcskey=""):
"""
Reads `SIP`_ header keywords and returns a `~astropy.wcs.Sip`
object.
If no `SIP`_ header keywords are found, ``None`` is returned.
"""
if isinstance(header, (str, bytes)):
# TODO: Parse SIP from a string without pyfits around
return None
if str("A_ORDER") in header and header[str('A_ORDER')] > 1:
if str("B_ORDER") not in header:
raise ValueError(
"A_ORDER provided without corresponding B_ORDER "
"keyword for SIP distortion")
m = int(header[str("A_ORDER")])
a = np.zeros((m + 1, m + 1), np.double)
for i in range(m + 1):
for j in range(m - i + 1):
key = str("A_{0}_{1}").format(i, j)
if key in header:
a[i, j] = header[key]
del header[key]
m = int(header[str("B_ORDER")])
if m > 1:
b = np.zeros((m + 1, m + 1), np.double)
for i in range(m + 1):
for j in range(m - i + 1):
key = str("B_{0}_{1}").format(i, j)
if key in header:
b[i, j] = header[key]
del header[key]
else:
a = None
b = None
del header[str('A_ORDER')]
del header[str('B_ORDER')]
ctype = [header['CTYPE{0}{1}'.format(nax, wcskey)] for nax in range(1, self.naxis + 1)]
if any(not ctyp.endswith('-SIP') for ctyp in ctype):
message = """
Inconsistent SIP distortion information is present in the FITS header and the WCS object:
SIP coefficients were detected, but CTYPE is missing a "-SIP" suffix.
astropy.wcs is using the SIP distortion coefficients,
therefore the coordinates calculated here might be incorrect.
If you do not want to apply the SIP distortion coefficients,
please remove the SIP coefficients from the FITS header or the
WCS object. As an example, if the image is already distortion-corrected
(e.g., drizzled) then distortion components should not apply and the SIP
coefficients should be removed.
While the SIP distortion coefficients are being applied here, if that was indeed the intent,
for consistency please append "-SIP" to the CTYPE in the FITS header or the WCS object.
"""
log.info(message)
elif str("B_ORDER") in header and header[str('B_ORDER')] > 1:
raise ValueError(
"B_ORDER provided without corresponding A_ORDER " +
"keyword for SIP distortion")
else:
a = None
b = None
if str("AP_ORDER") in header and header[str('AP_ORDER')] > 1:
if str("BP_ORDER") not in header:
raise ValueError(
"AP_ORDER provided without corresponding BP_ORDER "
"keyword for SIP distortion")
m = int(header[str("AP_ORDER")])
ap = np.zeros((m + 1, m + 1), np.double)
for i in range(m + 1):
for j in range(m - i + 1):
key = str("AP_{0}_{1}").format(i, j)
if key in header:
ap[i, j] = header[key]
del header[key]
m = int(header[str("BP_ORDER")])
if m > 1:
bp = np.zeros((m + 1, m + 1), np.double)
for i in range(m + 1):
for j in range(m - i + 1):
key = str("BP_{0}_{1}").format(i, j)
if key in header:
bp[i, j] = header[key]
del header[key]
else:
ap = None
bp = None
del header[str('AP_ORDER')]
del header[str('BP_ORDER')]
elif str("BP_ORDER") in header and header[str('BP_ORDER')] > 1:
raise ValueError(
"BP_ORDER provided without corresponding AP_ORDER "
"keyword for SIP distortion")
else:
ap = None
bp = None
if a is None and b is None and ap is None and bp is None:
return None
if str("CRPIX1{0}".format(wcskey)) not in header or str("CRPIX2{0}".format(wcskey)) not in header:
raise ValueError(
"Header has SIP keywords without CRPIX keywords")
crpix1 = header.get("CRPIX1{0}".format(wcskey))
crpix2 = header.get("CRPIX2{0}".format(wcskey))
return Sip(a, b, ap, bp, (crpix1, crpix2))
def _write_sip_kw(self):
"""
Write out SIP keywords. Returns a dictionary of key-value
pairs.
"""
if self.sip is None:
return {}
keywords = {}
def write_array(name, a):
if a is None:
return
size = a.shape[0]
keywords[str('{0}_ORDER').format(name)] = size - 1
for i in range(size):
for j in range(size - i):
if a[i, j] != 0.0:
keywords[
str('{0}_{1:d}_{2:d}').format(name, i, j)] = a[i, j]
write_array(str('A'), self.sip.a)
write_array(str('B'), self.sip.b)
write_array(str('AP'), self.sip.ap)
write_array(str('BP'), self.sip.bp)
return keywords
def _denormalize_sky(self, sky):
if self.wcs.lngtyp != 'RA':
raise ValueError(
"WCS does not have longitude type of 'RA', therefore " +
"(ra, dec) data can not be used as input")
if self.wcs.lattyp != 'DEC':
raise ValueError(
"WCS does not have longitude type of 'DEC', therefore " +
"(ra, dec) data can not be used as input")
if self.wcs.naxis == 2:
if self.wcs.lng == 0 and self.wcs.lat == 1:
return sky
elif self.wcs.lng == 1 and self.wcs.lat == 0:
# Reverse the order of the columns
return sky[:, ::-1]
else:
raise ValueError(
"WCS does not have longitude and latitude celestial " +
"axes, therefore (ra, dec) data can not be used as input")
else:
if self.wcs.lng < 0 or self.wcs.lat < 0:
raise ValueError(
"WCS does not have both longitude and latitude "
"celestial axes, therefore (ra, dec) data can not be " +
"used as input")
out = np.zeros((sky.shape[0], self.wcs.naxis))
out[:, self.wcs.lng] = sky[:, 0]
out[:, self.wcs.lat] = sky[:, 1]
return out
def _normalize_sky(self, sky):
if self.wcs.lngtyp != 'RA':
raise ValueError(
"WCS does not have longitude type of 'RA', therefore " +
"(ra, dec) data can not be returned")
if self.wcs.lattyp != 'DEC':
raise ValueError(
"WCS does not have longitude type of 'DEC', therefore " +
"(ra, dec) data can not be returned")
if self.wcs.naxis == 2:
if self.wcs.lng == 0 and self.wcs.lat == 1:
return sky
elif self.wcs.lng == 1 and self.wcs.lat == 0:
# Reverse the order of the columns
return sky[:, ::-1]
else:
raise ValueError(
"WCS does not have longitude and latitude celestial "
"axes, therefore (ra, dec) data can not be returned")
else:
if self.wcs.lng < 0 or self.wcs.lat < 0:
raise ValueError(
"WCS does not have both longitude and latitude celestial "
"axes, therefore (ra, dec) data can not be returned")
out = np.empty((sky.shape[0], 2))
out[:, 0] = sky[:, self.wcs.lng]
out[:, 1] = sky[:, self.wcs.lat]
return out
def _array_converter(self, func, sky, *args, ra_dec_order=False):
"""
A helper function to support reading either a pair of arrays
or a single Nx2 array.
"""
def _return_list_of_arrays(axes, origin):
try:
axes = np.broadcast_arrays(*axes)
except ValueError:
raise ValueError(
"Coordinate arrays are not broadcastable to each other")
xy = np.hstack([x.reshape((x.size, 1)) for x in axes])
if ra_dec_order and sky == 'input':
xy = self._denormalize_sky(xy)
output = func(xy, origin)
if ra_dec_order and sky == 'output':
output = self._normalize_sky(output)
return (output[:, 0].reshape(axes[0].shape),
output[:, 1].reshape(axes[0].shape))
return [output[:, i].reshape(axes[0].shape)
for i in range(output.shape[1])]
def _return_single_array(xy, origin):
if xy.shape[-1] != self.naxis:
raise ValueError(
"When providing two arguments, the array must be "
"of shape (N, {0})".format(self.naxis))
if ra_dec_order and sky == 'input':
xy = self._denormalize_sky(xy)
result = func(xy, origin)
if ra_dec_order and sky == 'output':
result = self._normalize_sky(result)
return result
if len(args) == 2:
try:
xy, origin = args
xy = np.asarray(xy)
origin = int(origin)
except Exception:
raise TypeError(
"When providing two arguments, they must be "
"(coords[N][{0}], origin)".format(self.naxis))
if self.naxis == 1 and len(xy.shape) == 1:
return _return_list_of_arrays([xy], origin)
return _return_single_array(xy, origin)
elif len(args) == self.naxis + 1:
axes = args[:-1]
origin = args[-1]
try:
axes = [np.asarray(x) for x in axes]
origin = int(origin)
except Exception:
raise TypeError(
"When providing more than two arguments, they must be " +
"a 1-D array for each axis, followed by an origin.")
return _return_list_of_arrays(axes, origin)
raise TypeError(
"WCS projection has {0} dimensions, so expected 2 (an Nx{0} array "
"and the origin argument) or {1} arguments (the position in each "
"dimension, and the origin argument). Instead, {2} arguments were "
"given.".format(
self.naxis, self.naxis + 1, len(args)))
def all_pix2world(self, *args, **kwargs):
return self._array_converter(
self._all_pix2world, 'output', *args, **kwargs)
all_pix2world.__doc__ = """
Transforms pixel coordinates to world coordinates.
Performs all of the following in series:
- Detector to image plane correction (if present in the
FITS file)
- `SIP`_ distortion correction (if present in the FITS
file)
- `distortion paper`_ table-lookup correction (if present
in the FITS file)
- `wcslib`_ "core" WCS transformation
Parameters
----------
{0}
For a transformation that is not two-dimensional, the
two-argument form must be used.
{1}
Returns
-------
{2}
Notes
-----
The order of the axes for the result is determined by the
``CTYPEia`` keywords in the FITS header, therefore it may not
always be of the form (*ra*, *dec*). The
`~astropy.wcs.Wcsprm.lat`, `~astropy.wcs.Wcsprm.lng`,
`~astropy.wcs.Wcsprm.lattyp` and `~astropy.wcs.Wcsprm.lngtyp`
members can be used to determine the order of the axes.
Raises
------
MemoryError
Memory allocation failed.
SingularMatrixError
Linear transformation matrix is singular.
InconsistentAxisTypesError
Inconsistent or unrecognized coordinate axis types.
ValueError
Invalid parameter value.
ValueError
Invalid coordinate transformation parameters.
ValueError
x- and y-coordinate arrays are not the same size.
InvalidTransformError
Invalid coordinate transformation parameters.
InvalidTransformError
Ill-conditioned coordinate transformation parameters.
""".format(__.TWO_OR_MORE_ARGS('naxis', 8),
__.RA_DEC_ORDER(8),
__.RETURNS('sky coordinates, in degrees', 8))
def wcs_pix2world(self, *args, **kwargs):
if self.wcs is None:
raise ValueError("No basic WCS settings were created.")
return self._array_converter(
lambda xy, o: self.wcs.p2s(xy, o)['world'],
'output', *args, **kwargs)
wcs_pix2world.__doc__ = """
Transforms pixel coordinates to world coordinates by doing
only the basic `wcslib`_ transformation.
No `SIP`_ or `distortion paper`_ table lookup correction is
applied. To perform distortion correction, see
`~astropy.wcs.WCS.all_pix2world`,
`~astropy.wcs.WCS.sip_pix2foc`, `~astropy.wcs.WCS.p4_pix2foc`,
or `~astropy.wcs.WCS.pix2foc`.
Parameters
----------
{0}
For a transformation that is not two-dimensional, the
two-argument form must be used.
{1}
Returns
-------
{2}
Raises
------
MemoryError
Memory allocation failed.
SingularMatrixError
Linear transformation matrix is singular.
InconsistentAxisTypesError
Inconsistent or unrecognized coordinate axis types.
ValueError
Invalid parameter value.
ValueError
Invalid coordinate transformation parameters.
ValueError
x- and y-coordinate arrays are not the same size.
InvalidTransformError
Invalid coordinate transformation parameters.
InvalidTransformError
Ill-conditioned coordinate transformation parameters.
Notes
-----
The order of the axes for the result is determined by the
``CTYPEia`` keywords in the FITS header, therefore it may not
always be of the form (*ra*, *dec*). The
`~astropy.wcs.Wcsprm.lat`, `~astropy.wcs.Wcsprm.lng`,
`~astropy.wcs.Wcsprm.lattyp` and `~astropy.wcs.Wcsprm.lngtyp`
members can be used to determine the order of the axes.
""".format(__.TWO_OR_MORE_ARGS('naxis', 8),
__.RA_DEC_ORDER(8),
__.RETURNS('world coordinates, in degrees', 8))
def _all_world2pix(self, world, origin, tolerance, maxiter, adaptive,
detect_divergence, quiet):
# ############################################################
# # DESCRIPTION OF THE NUMERICAL METHOD ##
# ############################################################
# In this section I will outline the method of solving
# the inverse problem of converting world coordinates to
# pixel coordinates (*inverse* of the direct transformation
# `all_pix2world`) and I will summarize some of the aspects
# of the method proposed here and some of the issues of the
# original `all_world2pix` (in relation to this method)
# discussed in https://github.com/astropy/astropy/issues/1977
# A more detailed discussion can be found here:
# https://github.com/astropy/astropy/pull/2373
#
#
# ### Background ###
#
#
# I will refer here to the [SIP Paper]
# (http://fits.gsfc.nasa.gov/registry/sip/SIP_distortion_v1_0.pdf).
# According to this paper, the effect of distortions as
# described in *their* equation (1) is:
#
# (1) x = CD*(u+f(u)),
#
# where `x` is a *vector* of "intermediate spherical
# coordinates" (equivalent to (x,y) in the paper) and `u`
# is a *vector* of "pixel coordinates", and `f` is a vector
# function describing geometrical distortions
# (see equations 2 and 3 in SIP Paper.
# However, I prefer to use `w` for "intermediate world
# coordinates", `x` for pixel coordinates, and assume that
# transformation `W` performs the **linear**
# (CD matrix + projection onto celestial sphere) part of the
# conversion from pixel coordinates to world coordinates.
# Then we can re-write (1) as:
#
# (2) w = W*(x+f(x)) = T(x)
#
# In `astropy.wcs.WCS` transformation `W` is represented by
# the `wcs_pix2world` member, while the combined ("total")
# transformation (linear part + distortions) is performed by
# `all_pix2world`. Below I summarize the notations and their
# equivalents in `astropy.wcs.WCS`:
#
# | Equation term | astropy.WCS/meaning |
# | ------------- | ---------------------------- |
# | `x` | pixel coordinates |
# | `w` | world coordinates |
# | `W` | `wcs_pix2world()` |
# | `W^{-1}` | `wcs_world2pix()` |
# | `T` | `all_pix2world()` |
# | `x+f(x)` | `pix2foc()` |
#
#
# ### Direct Solving of Equation (2) ###
#
#
# In order to find the pixel coordinates that correspond to
# given world coordinates `w`, it is necessary to invert
# equation (2): `x=T^{-1}(w)`, or solve equation `w==T(x)`
# for `x`. However, this approach has the following
# disadvantages:
# 1. It requires unnecessary transformations (see next
# section).
# 2. It is prone to "RA wrapping" issues as described in
# https://github.com/astropy/astropy/issues/1977
# (essentially because `all_pix2world` may return points with
# a different phase than user's input `w`).
#
#
# ### Description of the Method Used here ###
#
#
# By applying inverse linear WCS transformation (`W^{-1}`)
# to both sides of equation (2) and introducing notation `x'`
# (prime) for the pixels coordinates obtained from the world
# coordinates by applying inverse *linear* WCS transformation
# ("focal plane coordinates"):
#
# (3) x' = W^{-1}(w)
#
# we obtain the following equation:
#
# (4) x' = x+f(x),
#
# or,
#
# (5) x = x'-f(x)
#
# This equation is well suited for solving using the method
# of fixed-point iterations
# (http://en.wikipedia.org/wiki/Fixed-point_iteration):
#
# (6) x_{i+1} = x'-f(x_i)
#
# As an initial value of the pixel coordinate `x_0` we take
# "focal plane coordinate" `x'=W^{-1}(w)=wcs_world2pix(w)`.
# We stop iterations when `|x_{i+1}-x_i|<tolerance`. We also
# consider the process to be diverging if
# `|x_{i+1}-x_i|>|x_i-x_{i-1}|`
# **when** `|x_{i+1}-x_i|>=tolerance` (when current
# approximation is close to the true solution,
# `|x_{i+1}-x_i|>|x_i-x_{i-1}|` may be due to rounding errors
# and we ignore such "divergences" when
# `|x_{i+1}-x_i|<tolerance`). It may appear that checking for
# `|x_{i+1}-x_i|<tolerance` in order to ignore divergence is
# unnecessary since the iterative process should stop anyway,
# however, the proposed implementation of this iterative
# process is completely vectorized and, therefore, we may
# continue iterating over *some* points even though they have
# converged to within a specified tolerance (while iterating
# over other points that have not yet converged to
# a solution).
#
# In order to efficiently implement iterative process (6)
# using available methods in `astropy.wcs.WCS`, we add and
# subtract `x_i` from the right side of equation (6):
#
# (7) x_{i+1} = x'-(x_i+f(x_i))+x_i = x'-pix2foc(x_i)+x_i,
#
# where `x'=wcs_world2pix(w)` and it is computed only *once*
# before the beginning of the iterative process (and we also
# set `x_0=x'`). By using `pix2foc` at each iteration instead
# of `all_pix2world` we get about 25% increase in performance
# (by not performing the linear `W` transformation at each
# step) and we also avoid the "RA wrapping" issue described
# above (by working in focal plane coordinates and avoiding
# pix->world transformations).
#
# As an added benefit, the process converges to the correct
# solution in just one iteration when distortions are not
# present (compare to
# https://github.com/astropy/astropy/issues/1977 and
# https://github.com/astropy/astropy/pull/2294): in this case
# `pix2foc` is the identical transformation
# `x_i=pix2foc(x_i)` and from equation (7) we get:
#
# x' = x_0 = wcs_world2pix(w)
# x_1 = x' - pix2foc(x_0) + x_0 = x' - pix2foc(x') + x' = x'
# = wcs_world2pix(w) = x_0
# =>
# |x_1-x_0| = 0 < tolerance (with tolerance > 0)
#
# However, for performance reasons, it is still better to
# avoid iterations altogether and return the exact linear
# solution (`wcs_world2pix`) right-away when non-linear
# distortions are not present by checking that attributes
# `sip`, `cpdis1`, `cpdis2`, `det2im1`, and `det2im2` are
# *all* `None`.
#
#
# ### Outline of the Algorithm ###
#
#
# While the proposed code is relatively long (considering
# the simplicity of the algorithm), this is due to: 1)
# checking if iterative solution is necessary at all; 2)
# checking for divergence; 3) re-implementation of the
# completely vectorized algorithm as an "adaptive" vectorized
# algorithm (for cases when some points diverge for which we
# want to stop iterations). In my tests, the adaptive version
# of the algorithm is about 50% slower than non-adaptive
# version for all HST images.
#
# The essential part of the vectorized non-adaptive algorithm
# (without divergence and other checks) can be described
# as follows:
#
# pix0 = self.wcs_world2pix(world, origin)
# pix = pix0.copy() # 0-order solution
#
# for k in range(maxiter):
# # find correction to the previous solution:
# dpix = self.pix2foc(pix, origin) - pix0
#
# # compute norm (L2) of the correction:
# dn = np.linalg.norm(dpix, axis=1)
#
# # apply correction:
# pix -= dpix
#
# # check convergence:
# if np.max(dn) < tolerance:
# break
#
# return pix
#
# Here, the input parameter `world` can be a `MxN` array
# where `M` is the number of coordinate axes in WCS and `N`
# is the number of points to be converted simultaneously to
# image coordinates.
#
#
# ### IMPORTANT NOTE: ###
#
# If, in the future releases of the `~astropy.wcs`,
# `pix2foc` will not apply all the required distortion
# corrections then in the code below, calls to `pix2foc` will
# have to be replaced with
# wcs_world2pix(all_pix2world(pix_list, origin), origin)
#
# ############################################################
# # INITIALIZE ITERATIVE PROCESS: ##
# ############################################################
# initial approximation (linear WCS based only)
pix0 = self.wcs_world2pix(world, origin)
# Check that an iterative solution is required at all
# (when any of the non-CD-matrix-based corrections are
# present). If not required return the initial
# approximation (pix0).
if self.sip is None and \
self.cpdis1 is None and self.cpdis2 is None and \
self.det2im1 is None and self.det2im2 is None:
# No non-WCS corrections detected so
# simply return initial approximation:
return pix0
pix = pix0.copy() # 0-order solution
# initial correction:
dpix = self.pix2foc(pix, origin) - pix0
# Update initial solution:
pix -= dpix
# Norm (L2) squared of the correction:
dn = np.sum(dpix*dpix, axis=1)
dnprev = dn.copy() # if adaptive else dn
tol2 = tolerance**2
# Prepare for iterative process
k = 1
ind = None
inddiv = None
# Turn off numpy runtime warnings for 'invalid' and 'over':
old_invalid = np.geterr()['invalid']
old_over = np.geterr()['over']
np.seterr(invalid='ignore', over='ignore')
# ############################################################
# # NON-ADAPTIVE ITERATIONS: ##
# ############################################################
if not adaptive:
# Fixed-point iterations:
while (np.nanmax(dn) >= tol2 and k < maxiter):
# Find correction to the previous solution:
dpix = self.pix2foc(pix, origin) - pix0
# Compute norm (L2) squared of the correction:
dn = np.sum(dpix*dpix, axis=1)
# Check for divergence (we do this in two stages
# to optimize performance for the most common
# scenario when successive approximations converge):
if detect_divergence:
divergent = (dn >= dnprev)
if np.any(divergent):
# Find solutions that have not yet converged:
slowconv = (dn >= tol2)
inddiv, = np.where(divergent & slowconv)
if inddiv.shape[0] > 0:
# Update indices of elements that
# still need correction:
conv = (dn < dnprev)
iconv = np.where(conv)
# Apply correction:
dpixgood = dpix[iconv]
pix[iconv] -= dpixgood
dpix[iconv] = dpixgood
# For the next iteration choose
# non-divergent points that have not yet
# converged to the requested accuracy:
ind, = np.where(slowconv & conv)
pix0 = pix0[ind]
dnprev[ind] = dn[ind]
k += 1
# Switch to adaptive iterations:
adaptive = True
break
# Save current correction magnitudes for later:
dnprev = dn
# Apply correction:
pix -= dpix
k += 1
# ############################################################
# # ADAPTIVE ITERATIONS: ##
# ############################################################
if adaptive:
if ind is None:
ind, = np.where(np.isfinite(pix).all(axis=1))
pix0 = pix0[ind]
# "Adaptive" fixed-point iterations:
while (ind.shape[0] > 0 and k < maxiter):
# Find correction to the previous solution:
dpixnew = self.pix2foc(pix[ind], origin) - pix0
# Compute norm (L2) of the correction:
dnnew = np.sum(np.square(dpixnew), axis=1)
# Bookeeping of corrections:
dnprev[ind] = dn[ind].copy()
dn[ind] = dnnew
if detect_divergence:
# Find indices of pixels that are converging:
conv = (dnnew < dnprev[ind])
iconv = np.where(conv)
iiconv = ind[iconv]
# Apply correction:
dpixgood = dpixnew[iconv]
pix[iiconv] -= dpixgood
dpix[iiconv] = dpixgood
# Find indices of solutions that have not yet
# converged to the requested accuracy
# AND that do not diverge:
subind, = np.where((dnnew >= tol2) & conv)
else:
# Apply correction:
pix[ind] -= dpixnew
dpix[ind] = dpixnew
# Find indices of solutions that have not yet
# converged to the requested accuracy:
subind, = np.where(dnnew >= tol2)
# Choose solutions that need more iterations:
ind = ind[subind]
pix0 = pix0[subind]
k += 1
# ############################################################
# # FINAL DETECTION OF INVALID, DIVERGING, ##
# # AND FAILED-TO-CONVERGE POINTS ##
# ############################################################
# Identify diverging and/or invalid points:
invalid = ((~np.all(np.isfinite(pix), axis=1)) &
(np.all(np.isfinite(world), axis=1)))
# When detect_divergence==False, dnprev is outdated
# (it is the norm of the very first correction).
# Still better than nothing...
inddiv, = np.where(((dn >= tol2) & (dn >= dnprev)) | invalid)
if inddiv.shape[0] == 0:
inddiv = None
# Identify points that did not converge within 'maxiter'
# iterations:
if k >= maxiter:
ind, = np.where((dn >= tol2) & (dn < dnprev) & (~invalid))
if ind.shape[0] == 0:
ind = None
else:
ind = None
# Restore previous numpy error settings:
np.seterr(invalid=old_invalid, over=old_over)
# ############################################################
# # RAISE EXCEPTION IF DIVERGING OR TOO SLOWLY CONVERGING ##
# # DATA POINTS HAVE BEEN DETECTED: ##
# ############################################################
if (ind is not None or inddiv is not None) and not quiet:
if inddiv is None:
raise NoConvergence(
"'WCS.all_world2pix' failed to "
"converge to the requested accuracy after {:d} "
"iterations.".format(k), best_solution=pix,
accuracy=np.abs(dpix), niter=k,
slow_conv=ind, divergent=None)
else:
raise NoConvergence(
"'WCS.all_world2pix' failed to "
"converge to the requested accuracy.\n"
"After {0:d} iterations, the solution is diverging "
"at least for one input point."
.format(k), best_solution=pix,
accuracy=np.abs(dpix), niter=k,
slow_conv=ind, divergent=inddiv)
return pix
def all_world2pix(self, *args, tolerance=1e-4, maxiter=20, adaptive=False,
detect_divergence=True, quiet=False, **kwargs):
if self.wcs is None:
raise ValueError("No basic WCS settings were created.")
return self._array_converter(
lambda *args, **kwargs:
self._all_world2pix(
*args, tolerance=tolerance, maxiter=maxiter,
adaptive=adaptive, detect_divergence=detect_divergence,
quiet=quiet),
'input', *args, **kwargs
)
all_world2pix.__doc__ = """
all_world2pix(*arg, accuracy=1.0e-4, maxiter=20,
adaptive=False, detect_divergence=True, quiet=False)
Transforms world coordinates to pixel coordinates, using
numerical iteration to invert the full forward transformation
`~astropy.wcs.WCS.all_pix2world` with complete
distortion model.
Parameters
----------
{0}
For a transformation that is not two-dimensional, the
two-argument form must be used.
{1}
tolerance : float, optional (Default = 1.0e-4)
Tolerance of solution. Iteration terminates when the
iterative solver estimates that the "true solution" is
within this many pixels current estimate, more
specifically, when the correction to the solution found
during the previous iteration is smaller
(in the sense of the L2 norm) than ``tolerance``.
maxiter : int, optional (Default = 20)
Maximum number of iterations allowed to reach a solution.
quiet : bool, optional (Default = False)
Do not throw :py:class:`NoConvergence` exceptions when
the method does not converge to a solution with the
required accuracy within a specified number of maximum
iterations set by ``maxiter`` parameter. Instead,
simply return the found solution.
Other Parameters
----------------
adaptive : bool, optional (Default = False)
Specifies whether to adaptively select only points that
did not converge to a solution within the required
accuracy for the next iteration. Default is recommended
for HST as well as most other instruments.
.. note::
The :py:meth:`all_world2pix` uses a vectorized
implementation of the method of consecutive
approximations (see ``Notes`` section below) in which it
iterates over *all* input points *regardless* until
the required accuracy has been reached for *all* input
points. In some cases it may be possible that
*almost all* points have reached the required accuracy
but there are only a few of input data points for
which additional iterations may be needed (this
depends mostly on the characteristics of the geometric
distortions for a given instrument). In this situation
it may be advantageous to set ``adaptive`` = `True` in
which case :py:meth:`all_world2pix` will continue
iterating *only* over the points that have not yet
converged to the required accuracy. However, for the
HST's ACS/WFC detector, which has the strongest
distortions of all HST instruments, testing has
shown that enabling this option would lead to a about
50-100% penalty in computational time (depending on
specifics of the image, geometric distortions, and
number of input points to be converted). Therefore,
for HST and possibly instruments, it is recommended
to set ``adaptive`` = `False`. The only danger in
getting this setting wrong will be a performance
penalty.
.. note::
When ``detect_divergence`` is `True`,
:py:meth:`all_world2pix` will automatically switch
to the adaptive algorithm once divergence has been
detected.
detect_divergence : bool, optional (Default = True)
Specifies whether to perform a more detailed analysis
of the convergence to a solution. Normally
:py:meth:`all_world2pix` may not achieve the required
accuracy if either the ``tolerance`` or ``maxiter`` arguments
are too low. However, it may happen that for some
geometric distortions the conditions of convergence for
the the method of consecutive approximations used by
:py:meth:`all_world2pix` may not be satisfied, in which
case consecutive approximations to the solution will
diverge regardless of the ``tolerance`` or ``maxiter``
settings.
When ``detect_divergence`` is `False`, these divergent
points will be detected as not having achieved the
required accuracy (without further details). In addition,
if ``adaptive`` is `False` then the algorithm will not
know that the solution (for specific points) is diverging
and will continue iterating and trying to "improve"
diverging solutions. This may result in ``NaN`` or
``Inf`` values in the return results (in addition to a
performance penalties). Even when ``detect_divergence``
is `False`, :py:meth:`all_world2pix`, at the end of the
iterative process, will identify invalid results
(``NaN`` or ``Inf``) as "diverging" solutions and will
raise :py:class:`NoConvergence` unless the ``quiet``
parameter is set to `True`.
When ``detect_divergence`` is `True`,
:py:meth:`all_world2pix` will detect points for which
current correction to the coordinates is larger than
the correction applied during the previous iteration
**if** the requested accuracy **has not yet been
achieved**. In this case, if ``adaptive`` is `True`,
these points will be excluded from further iterations and
if ``adaptive`` is `False`, :py:meth:`all_world2pix` will
automatically switch to the adaptive algorithm. Thus, the
reported divergent solution will be the latest converging
solution computed immediately *before* divergence
has been detected.
.. note::
When accuracy has been achieved, small increases in
current corrections may be possible due to rounding
errors (when ``adaptive`` is `False`) and such
increases will be ignored.
.. note::
Based on our testing using HST ACS/WFC images, setting
``detect_divergence`` to `True` will incur about 5-20%
performance penalty with the larger penalty
corresponding to ``adaptive`` set to `True`.
Because the benefits of enabling this
feature outweigh the small performance penalty,
especially when ``adaptive`` = `False`, it is
recommended to set ``detect_divergence`` to `True`,
unless extensive testing of the distortion models for
images from specific instruments show a good stability
of the numerical method for a wide range of
coordinates (even outside the image itself).
.. note::
Indices of the diverging inverse solutions will be
reported in the ``divergent`` attribute of the
raised :py:class:`NoConvergence` exception object.
Returns
-------
{2}
Notes
-----
The order of the axes for the input world array is determined by
the ``CTYPEia`` keywords in the FITS header, therefore it may
not always be of the form (*ra*, *dec*). The
`~astropy.wcs.Wcsprm.lat`, `~astropy.wcs.Wcsprm.lng`,
`~astropy.wcs.Wcsprm.lattyp`, and
`~astropy.wcs.Wcsprm.lngtyp`
members can be used to determine the order of the axes.
Using the method of fixed-point iterations approximations we
iterate starting with the initial approximation, which is
computed using the non-distortion-aware
:py:meth:`wcs_world2pix` (or equivalent).
The :py:meth:`all_world2pix` function uses a vectorized
implementation of the method of consecutive approximations and
therefore it is highly efficient (>30x) when *all* data points
that need to be converted from sky coordinates to image
coordinates are passed at *once*. Therefore, it is advisable,
whenever possible, to pass as input a long array of all points
that need to be converted to :py:meth:`all_world2pix` instead
of calling :py:meth:`all_world2pix` for each data point. Also
see the note to the ``adaptive`` parameter.
Raises
------
NoConvergence
The method did not converge to a
solution to the required accuracy within a specified
number of maximum iterations set by the ``maxiter``
parameter. To turn off this exception, set ``quiet`` to
`True`. Indices of the points for which the requested
accuracy was not achieved (if any) will be listed in the
``slow_conv`` attribute of the
raised :py:class:`NoConvergence` exception object.
See :py:class:`NoConvergence` documentation for
more details.
MemoryError
Memory allocation failed.
SingularMatrixError
Linear transformation matrix is singular.
InconsistentAxisTypesError
Inconsistent or unrecognized coordinate axis types.
ValueError
Invalid parameter value.
ValueError
Invalid coordinate transformation parameters.
ValueError
x- and y-coordinate arrays are not the same size.
InvalidTransformError
Invalid coordinate transformation parameters.
InvalidTransformError
Ill-conditioned coordinate transformation parameters.
Examples
--------
>>> import astropy.io.fits as fits
>>> import astropy.wcs as wcs
>>> import numpy as np
>>> import os
>>> filename = os.path.join(wcs.__path__[0], 'tests/data/j94f05bgq_flt.fits')
>>> hdulist = fits.open(filename)
>>> w = wcs.WCS(hdulist[('sci',1)].header, hdulist)
>>> hdulist.close()
>>> ra, dec = w.all_pix2world([1,2,3], [1,1,1], 1)
>>> print(ra) # doctest: +FLOAT_CMP
[ 5.52645627 5.52649663 5.52653698]
>>> print(dec) # doctest: +FLOAT_CMP
[-72.05171757 -72.05171276 -72.05170795]
>>> radec = w.all_pix2world([[1,1], [2,1], [3,1]], 1)
>>> print(radec) # doctest: +FLOAT_CMP
[[ 5.52645627 -72.05171757]
[ 5.52649663 -72.05171276]
[ 5.52653698 -72.05170795]]
>>> x, y = w.all_world2pix(ra, dec, 1)
>>> print(x) # doctest: +FLOAT_CMP
[ 1.00000238 2.00000237 3.00000236]
>>> print(y) # doctest: +FLOAT_CMP
[ 0.99999996 0.99999997 0.99999997]
>>> xy = w.all_world2pix(radec, 1)
>>> print(xy) # doctest: +FLOAT_CMP
[[ 1.00000238 0.99999996]
[ 2.00000237 0.99999997]
[ 3.00000236 0.99999997]]
>>> xy = w.all_world2pix(radec, 1, maxiter=3,
... tolerance=1.0e-10, quiet=False)
Traceback (most recent call last):
...
NoConvergence: 'WCS.all_world2pix' failed to converge to the
requested accuracy. After 3 iterations, the solution is
diverging at least for one input point.
>>> # Now try to use some diverging data:
>>> divradec = w.all_pix2world([[1.0, 1.0],
... [10000.0, 50000.0],
... [3.0, 1.0]], 1)
>>> print(divradec) # doctest: +FLOAT_CMP
[[ 5.52645627 -72.05171757]
[ 7.15976932 -70.8140779 ]
[ 5.52653698 -72.05170795]]
>>> # First, turn detect_divergence on:
>>> try: # doctest: +FLOAT_CMP
... xy = w.all_world2pix(divradec, 1, maxiter=20,
... tolerance=1.0e-4, adaptive=False,
... detect_divergence=True,
... quiet=False)
... except wcs.wcs.NoConvergence as e:
... print("Indices of diverging points: {{0}}"
... .format(e.divergent))
... print("Indices of poorly converging points: {{0}}"
... .format(e.slow_conv))
... print("Best solution:\\n{{0}}".format(e.best_solution))
... print("Achieved accuracy:\\n{{0}}".format(e.accuracy))
Indices of diverging points: [1]
Indices of poorly converging points: None
Best solution:
[[ 1.00000238e+00 9.99999965e-01]
[ -1.99441636e+06 1.44309097e+06]
[ 3.00000236e+00 9.99999966e-01]]
Achieved accuracy:
[[ 6.13968380e-05 8.59638593e-07]
[ 8.59526812e+11 6.61713548e+11]
[ 6.09398446e-05 8.38759724e-07]]
>>> raise e
Traceback (most recent call last):
...
NoConvergence: 'WCS.all_world2pix' failed to converge to the
requested accuracy. After 5 iterations, the solution is
diverging at least for one input point.
>>> # This time turn detect_divergence off:
>>> try: # doctest: +FLOAT_CMP
... xy = w.all_world2pix(divradec, 1, maxiter=20,
... tolerance=1.0e-4, adaptive=False,
... detect_divergence=False,
... quiet=False)
... except wcs.wcs.NoConvergence as e:
... print("Indices of diverging points: {{0}}"
... .format(e.divergent))
... print("Indices of poorly converging points: {{0}}"
... .format(e.slow_conv))
... print("Best solution:\\n{{0}}".format(e.best_solution))
... print("Achieved accuracy:\\n{{0}}".format(e.accuracy))
Indices of diverging points: [1]
Indices of poorly converging points: None
Best solution:
[[ 1.00000009 1. ]
[ nan nan]
[ 3.00000009 1. ]]
Achieved accuracy:
[[ 2.29417358e-06 3.21222995e-08]
[ nan nan]
[ 2.27407877e-06 3.13005639e-08]]
>>> raise e
Traceback (most recent call last):
...
NoConvergence: 'WCS.all_world2pix' failed to converge to the
requested accuracy. After 6 iterations, the solution is
diverging at least for one input point.
""".format(__.TWO_OR_MORE_ARGS('naxis', 8),
__.RA_DEC_ORDER(8),
__.RETURNS('pixel coordinates', 8))
def wcs_world2pix(self, *args, **kwargs):
if self.wcs is None:
raise ValueError("No basic WCS settings were created.")
return self._array_converter(
lambda xy, o: self.wcs.s2p(xy, o)['pixcrd'],
'input', *args, **kwargs)
wcs_world2pix.__doc__ = """
Transforms world coordinates to pixel coordinates, using only
the basic `wcslib`_ WCS transformation. No `SIP`_ or
`distortion paper`_ table lookup transformation is applied.
Parameters
----------
{0}
For a transformation that is not two-dimensional, the
two-argument form must be used.
{1}
Returns
-------
{2}
Notes
-----
The order of the axes for the input world array is determined by
the ``CTYPEia`` keywords in the FITS header, therefore it may
not always be of the form (*ra*, *dec*). The
`~astropy.wcs.Wcsprm.lat`, `~astropy.wcs.Wcsprm.lng`,
`~astropy.wcs.Wcsprm.lattyp` and `~astropy.wcs.Wcsprm.lngtyp`
members can be used to determine the order of the axes.
Raises
------
MemoryError
Memory allocation failed.
SingularMatrixError
Linear transformation matrix is singular.
InconsistentAxisTypesError
Inconsistent or unrecognized coordinate axis types.
ValueError
Invalid parameter value.
ValueError
Invalid coordinate transformation parameters.
ValueError
x- and y-coordinate arrays are not the same size.
InvalidTransformError
Invalid coordinate transformation parameters.
InvalidTransformError
Ill-conditioned coordinate transformation parameters.
""".format(__.TWO_OR_MORE_ARGS('naxis', 8),
__.RA_DEC_ORDER(8),
__.RETURNS('pixel coordinates', 8))
def pix2foc(self, *args):
return self._array_converter(self._pix2foc, None, *args)
pix2foc.__doc__ = """
Convert pixel coordinates to focal plane coordinates using the
`SIP`_ polynomial distortion convention and `distortion
paper`_ table-lookup correction.
The output is in absolute pixel coordinates, not relative to
``CRPIX``.
Parameters
----------
{0}
Returns
-------
{1}
Raises
------
MemoryError
Memory allocation failed.
ValueError
Invalid coordinate transformation parameters.
""".format(__.TWO_OR_MORE_ARGS('2', 8),
__.RETURNS('focal coordinates', 8))
def p4_pix2foc(self, *args):
return self._array_converter(self._p4_pix2foc, None, *args)
p4_pix2foc.__doc__ = """
Convert pixel coordinates to focal plane coordinates using
`distortion paper`_ table-lookup correction.
The output is in absolute pixel coordinates, not relative to
``CRPIX``.
Parameters
----------
{0}
Returns
-------
{1}
Raises
------
MemoryError
Memory allocation failed.
ValueError
Invalid coordinate transformation parameters.
""".format(__.TWO_OR_MORE_ARGS('2', 8),
__.RETURNS('focal coordinates', 8))
def det2im(self, *args):
return self._array_converter(self._det2im, None, *args)
det2im.__doc__ = """
Convert detector coordinates to image plane coordinates using
`distortion paper`_ table-lookup correction.
The output is in absolute pixel coordinates, not relative to
``CRPIX``.
Parameters
----------
{0}
Returns
-------
{1}
Raises
------
MemoryError
Memory allocation failed.
ValueError
Invalid coordinate transformation parameters.
""".format(__.TWO_OR_MORE_ARGS('2', 8),
__.RETURNS('pixel coordinates', 8))
def sip_pix2foc(self, *args):
if self.sip is None:
if len(args) == 2:
return args[0]
elif len(args) == 3:
return args[:2]
else:
raise TypeError("Wrong number of arguments")
return self._array_converter(self.sip.pix2foc, None, *args)
sip_pix2foc.__doc__ = """
Convert pixel coordinates to focal plane coordinates using the
`SIP`_ polynomial distortion convention.
The output is in pixel coordinates, relative to ``CRPIX``.
FITS WCS `distortion paper`_ table lookup correction is not
applied, even if that information existed in the FITS file
that initialized this :class:`~astropy.wcs.WCS` object. To
correct for that, use `~astropy.wcs.WCS.pix2foc` or
`~astropy.wcs.WCS.p4_pix2foc`.
Parameters
----------
{0}
Returns
-------
{1}
Raises
------
MemoryError
Memory allocation failed.
ValueError
Invalid coordinate transformation parameters.
""".format(__.TWO_OR_MORE_ARGS('2', 8),
__.RETURNS('focal coordinates', 8))
def sip_foc2pix(self, *args):
if self.sip is None:
if len(args) == 2:
return args[0]
elif len(args) == 3:
return args[:2]
else:
raise TypeError("Wrong number of arguments")
return self._array_converter(self.sip.foc2pix, None, *args)
sip_foc2pix.__doc__ = """
Convert focal plane coordinates to pixel coordinates using the
`SIP`_ polynomial distortion convention.
FITS WCS `distortion paper`_ table lookup distortion
correction is not applied, even if that information existed in
the FITS file that initialized this `~astropy.wcs.WCS` object.
Parameters
----------
{0}
Returns
-------
{1}
Raises
------
MemoryError
Memory allocation failed.
ValueError
Invalid coordinate transformation parameters.
""".format(__.TWO_OR_MORE_ARGS('2', 8),
__.RETURNS('pixel coordinates', 8))
def to_fits(self, relax=False, key=None):
"""
Generate an `astropy.io.fits.HDUList` object with all of the
information stored in this object. This should be logically identical
to the input FITS file, but it will be normalized in a number of ways.
See `to_header` for some warnings about the output produced.
Parameters
----------
relax : bool or int, optional
Degree of permissiveness:
- `False` (default): Write all extensions that are
considered to be safe and recommended.
- `True`: Write all recognized informal extensions of the
WCS standard.
- `int`: a bit field selecting specific extensions to
write. See :ref:`relaxwrite` for details.
key : str
The name of a particular WCS transform to use. This may be
either ``' '`` or ``'A'``-``'Z'`` and corresponds to the ``"a"``
part of the ``CTYPEia`` cards.
Returns
-------
hdulist : `astropy.io.fits.HDUList`
"""
header = self.to_header(relax=relax, key=key)
hdu = fits.PrimaryHDU(header=header)
hdulist = fits.HDUList(hdu)
self._write_det2im(hdulist)
self._write_distortion_kw(hdulist)
return hdulist
def to_header(self, relax=None, key=None):
"""Generate an `astropy.io.fits.Header` object with the basic WCS
and SIP information stored in this object. This should be
logically identical to the input FITS file, but it will be
normalized in a number of ways.
.. warning::
This function does not write out FITS WCS `distortion
paper`_ information, since that requires multiple FITS
header data units. To get a full representation of
everything in this object, use `to_fits`.
Parameters
----------
relax : bool or int, optional
Degree of permissiveness:
- `False` (default): Write all extensions that are
considered to be safe and recommended.
- `True`: Write all recognized informal extensions of the
WCS standard.
- `int`: a bit field selecting specific extensions to
write. See :ref:`relaxwrite` for details.
If the ``relax`` keyword argument is not given and any
keywords were omitted from the output, an
`~astropy.utils.exceptions.AstropyWarning` is displayed.
To override this, explicitly pass a value to ``relax``.
key : str
The name of a particular WCS transform to use. This may be
either ``' '`` or ``'A'``-``'Z'`` and corresponds to the ``"a"``
part of the ``CTYPEia`` cards.
Returns
-------
header : `astropy.io.fits.Header`
Notes
-----
The output header will almost certainly differ from the input in a
number of respects:
1. The output header only contains WCS-related keywords. In
particular, it does not contain syntactically-required
keywords such as ``SIMPLE``, ``NAXIS``, ``BITPIX``, or
``END``.
2. Deprecated (e.g. ``CROTAn``) or non-standard usage will
be translated to standard (this is partially dependent on
whether ``fix`` was applied).
3. Quantities will be converted to the units used internally,
basically SI with the addition of degrees.
4. Floating-point quantities may be given to a different decimal
precision.
5. Elements of the ``PCi_j`` matrix will be written if and
only if they differ from the unit matrix. Thus, if the
matrix is unity then no elements will be written.
6. Additional keywords such as ``WCSAXES``, ``CUNITia``,
``LONPOLEa`` and ``LATPOLEa`` may appear.
7. The original keycomments will be lost, although
`to_header` tries hard to write meaningful comments.
8. Keyword order may be changed.
"""
# default precision for numerical WCS keywords
precision = WCSHDO_P14
display_warning = False
if relax is None:
display_warning = True
relax = False
if relax not in (True, False):
do_sip = relax & WCSHDO_SIP
relax &= ~WCSHDO_SIP
else:
do_sip = relax
relax = WCSHDO_all if relax is True else WCSHDO_safe
relax = precision | relax
if self.wcs is not None:
if key is not None:
orig_key = self.wcs.alt
self.wcs.alt = key
header_string = self.wcs.to_header(relax)
header = fits.Header.fromstring(header_string)
keys_to_remove = ["", " ", "COMMENT"]
for kw in keys_to_remove:
if kw in header:
del header[kw]
else:
header = fits.Header()
if do_sip and self.sip is not None:
if self.wcs is not None and any(not ctyp.endswith('-SIP') for ctyp in self.wcs.ctype):
self._fix_ctype(header, add_sip=True)
for kw, val in self._write_sip_kw().items():
header[kw] = val
if not do_sip and self.wcs is not None and any(self.wcs.ctype) and self.sip is not None:
# This is called when relax is not False or WCSHDO_SIP
# The default case of ``relax=None`` is handled further in the code.
header = self._fix_ctype(header, add_sip=False)
if display_warning:
full_header = self.to_header(relax=True, key=key)
missing_keys = []
for kw, val in full_header.items():
if kw not in header:
missing_keys.append(kw)
if len(missing_keys):
warnings.warn(
"Some non-standard WCS keywords were excluded: {0} "
"Use the ``relax`` kwarg to control this.".format(
', '.join(missing_keys)),
AstropyWarning)
# called when ``relax=None``
# This is different from the case of ``relax=False``.
if any(self.wcs.ctype) and self.sip is not None:
header = self._fix_ctype(header, add_sip=False, log_message=False)
# Finally reset the key. This must be called after ``_fix_ctype``.
if key is not None:
self.wcs.alt = orig_key
return header
def _fix_ctype(self, header, add_sip=True, log_message=True):
"""
Parameters
----------
header : `~astropy.io.fits.Header`
FITS header.
add_sip : bool
Flag indicating whether "-SIP" should be added or removed from CTYPE keywords.
Remove "-SIP" from CTYPE when writing out a header with relax=False.
This needs to be done outside ``to_header`` because ``to_header`` runs
twice when ``relax=False`` and the second time ``relax`` is set to ``True``
to display the missing keywords.
If the user requested SIP distortion to be written out add "-SIP" to
CTYPE if it is missing.
"""
_add_sip_to_ctype = """
Inconsistent SIP distortion information is present in the current WCS:
SIP coefficients were detected, but CTYPE is missing "-SIP" suffix,
therefore the current WCS is internally inconsistent.
Because relax has been set to True, the resulting output WCS will have
"-SIP" appended to CTYPE in order to make the header internally consistent.
However, this may produce incorrect astrometry in the output WCS, if
in fact the current WCS is already distortion-corrected.
Therefore, if current WCS is already distortion-corrected (eg, drizzled)
then SIP distortion components should not apply. In that case, for a WCS
that is already distortion-corrected, please remove the SIP coefficients
from the header.
"""
if log_message:
if add_sip:
log.info(_add_sip_to_ctype)
for i in range(1, self.naxis+1):
# strip() must be called here to cover the case of alt key= " "
kw = 'CTYPE{0}{1}'.format(i, self.wcs.alt).strip()
if kw in header:
if add_sip:
val = header[kw].strip("-SIP") + "-SIP"
else:
val = header[kw].strip("-SIP")
header[kw] = val
else:
continue
return header
def to_header_string(self, relax=None):
"""
Identical to `to_header`, but returns a string containing the
header cards.
"""
return str(self.to_header(relax))
def footprint_to_file(self, filename='footprint.reg', color='green',
width=2, coordsys=None):
"""
Writes out a `ds9`_ style regions file. It can be loaded
directly by `ds9`_.
Parameters
----------
filename : str, optional
Output file name - default is ``'footprint.reg'``
color : str, optional
Color to use when plotting the line.
width : int, optional
Width of the region line.
coordsys : str, optional
Coordinate system. If not specified (default), the ``radesys``
value is used. For all possible values, see
http://ds9.si.edu/doc/ref/region.html#RegionFileFormat
"""
comments = ('# Region file format: DS9 version 4.0 \n'
'# global color=green font="helvetica 12 bold '
'select=1 highlite=1 edit=1 move=1 delete=1 '
'include=1 fixed=0 source\n')
coordsys = coordsys or self.wcs.radesys
if coordsys not in ('PHYSICAL', 'IMAGE', 'FK4', 'B1950', 'FK5',
'J2000', 'GALACTIC', 'ECLIPTIC', 'ICRS', 'LINEAR',
'AMPLIFIER', 'DETECTOR'):
raise ValueError("Coordinate system '{}' is not supported. A valid"
" one can be given with the 'coordsys' argument."
.format(coordsys))
with open(filename, mode='w') as f:
f.write(comments)
f.write('{}\n'.format(coordsys))
f.write('polygon(')
self.calc_footprint().tofile(f, sep=',')
f.write(') # color={0}, width={1:d} \n'.format(color, width))
@property
def _naxis1(self):
return self._naxis[0]
@_naxis1.setter
def _naxis1(self, value):
self._naxis[0] = value
@property
def _naxis2(self):
return self._naxis[1]
@_naxis2.setter
def _naxis2(self, value):
self._naxis[1] = value
def _get_naxis(self, header=None):
_naxis = []
if (header is not None and
not isinstance(header, (str, bytes))):
for naxis in itertools.count(1):
try:
_naxis.append(header['NAXIS{}'.format(naxis)])
except KeyError:
break
if len(_naxis) == 0:
_naxis = [0, 0]
elif len(_naxis) == 1:
_naxis.append(0)
self._naxis = _naxis
def printwcs(self):
print(repr(self))
def __repr__(self):
'''
Return a short description. Simply porting the behavior from
the `printwcs()` method.
'''
description = ["WCS Keywords\n",
"Number of WCS axes: {0!r}".format(self.naxis)]
sfmt = ' : ' + "".join(["{"+"{0}".format(i)+"!r} " for i in range(self.naxis)])
keywords = ['CTYPE', 'CRVAL', 'CRPIX']
values = [self.wcs.ctype, self.wcs.crval, self.wcs.crpix]
for keyword, value in zip(keywords, values):
description.append(keyword+sfmt.format(*value))
if hasattr(self.wcs, 'pc'):
for i in range(self.naxis):
s = ''
for j in range(self.naxis):
s += ''.join(['PC', str(i+1), '_', str(j+1), ' '])
s += sfmt
description.append(s.format(*self.wcs.pc[i]))
s = 'CDELT' + sfmt
description.append(s.format(*self.wcs.cdelt))
elif hasattr(self.wcs, 'cd'):
for i in range(self.naxis):
s = ''
for j in range(self.naxis):
s += "".join(['CD', str(i+1), '_', str(j+1), ' '])
s += sfmt
description.append(s.format(*self.wcs.cd[i]))
description.append('NAXIS : {}'.format(' '.join(map(str, self._naxis))))
return '\n'.join(description)
def get_axis_types(self):
"""
Similar to `self.wcsprm.axis_types <astropy.wcs.Wcsprm.axis_types>`
but provides the information in a more Python-friendly format.
Returns
-------
result : list of dicts
Returns a list of dictionaries, one for each axis, each
containing attributes about the type of that axis.
Each dictionary has the following keys:
- 'coordinate_type':
- None: Non-specific coordinate type.
- 'stokes': Stokes coordinate.
- 'celestial': Celestial coordinate (including ``CUBEFACE``).
- 'spectral': Spectral coordinate.
- 'scale':
- 'linear': Linear axis.
- 'quantized': Quantized axis (``STOKES``, ``CUBEFACE``).
- 'non-linear celestial': Non-linear celestial axis.
- 'non-linear spectral': Non-linear spectral axis.
- 'logarithmic': Logarithmic axis.
- 'tabular': Tabular axis.
- 'group'
- Group number, e.g. lookup table number
- 'number'
- For celestial axes:
- 0: Longitude coordinate.
- 1: Latitude coordinate.
- 2: ``CUBEFACE`` number.
- For lookup tables:
- the axis number in a multidimensional table.
``CTYPEia`` in ``"4-3"`` form with unrecognized algorithm code will
generate an error.
"""
if self.wcs is None:
raise AttributeError(
"This WCS object does not have a wcsprm object.")
coordinate_type_map = {
0: None,
1: 'stokes',
2: 'celestial',
3: 'spectral'}
scale_map = {
0: 'linear',
1: 'quantized',
2: 'non-linear celestial',
3: 'non-linear spectral',
4: 'logarithmic',
5: 'tabular'}
result = []
for axis_type in self.wcs.axis_types:
subresult = {}
coordinate_type = (axis_type // 1000) % 10
subresult['coordinate_type'] = coordinate_type_map[coordinate_type]
scale = (axis_type // 100) % 10
subresult['scale'] = scale_map[scale]
group = (axis_type // 10) % 10
subresult['group'] = group
number = axis_type % 10
subresult['number'] = number
result.append(subresult)
return result
def __reduce__(self):
"""
Support pickling of WCS objects. This is done by serializing
to an in-memory FITS file and dumping that as a string.
"""
hdulist = self.to_fits(relax=True)
buffer = io.BytesIO()
hdulist.writeto(buffer)
return (__WCS_unpickle__,
(self.__class__, self.__dict__, buffer.getvalue(),))
def dropaxis(self, dropax):
"""
Remove an axis from the WCS.
Parameters
----------
wcs : `~astropy.wcs.WCS`
The WCS with naxis to be chopped to naxis-1
dropax : int
The index of the WCS to drop, counting from 0 (i.e., python convention,
not FITS convention)
Returns
-------
A new `~astropy.wcs.WCS` instance with one axis fewer
"""
inds = list(range(self.wcs.naxis))
inds.pop(dropax)
# axis 0 has special meaning to sub
# if wcs.wcs.ctype == ['RA','DEC','VLSR'], you want
# wcs.sub([1,2]) to get 'RA','DEC' back
return self.sub([i+1 for i in inds])
def swapaxes(self, ax0, ax1):
"""
Swap axes in a WCS.
Parameters
----------
wcs : `~astropy.wcs.WCS`
The WCS to have its axes swapped
ax0 : int
ax1 : int
The indices of the WCS to be swapped, counting from 0 (i.e., python
convention, not FITS convention)
Returns
-------
A new `~astropy.wcs.WCS` instance with the same number of axes, but two
swapped
"""
inds = list(range(self.wcs.naxis))
inds[ax0], inds[ax1] = inds[ax1], inds[ax0]
return self.sub([i+1 for i in inds])
def reorient_celestial_first(self):
"""
Reorient the WCS such that the celestial axes are first, followed by
the spectral axis, followed by any others.
Assumes at least celestial axes are present.
"""
return self.sub([WCSSUB_CELESTIAL, WCSSUB_SPECTRAL, WCSSUB_STOKES])
def slice(self, view, numpy_order=True):
"""
Slice a WCS instance using a Numpy slice. The order of the slice should
be reversed (as for the data) compared to the natural WCS order.
Parameters
----------
view : tuple
A tuple containing the same number of slices as the WCS system.
The ``step`` method, the third argument to a slice, is not
presently supported.
numpy_order : bool
Use numpy order, i.e. slice the WCS so that an identical slice
applied to a numpy array will slice the array and WCS in the same
way. If set to `False`, the WCS will be sliced in FITS order,
meaning the first slice will be applied to the *last* numpy index
but the *first* WCS axis.
Returns
-------
wcs_new : `~astropy.wcs.WCS`
A new resampled WCS axis
"""
if hasattr(view, '__len__') and len(view) > self.wcs.naxis:
raise ValueError("Must have # of slices <= # of WCS axes")
elif not hasattr(view, '__len__'): # view MUST be an iterable
view = [view]
if not all(isinstance(x, slice) for x in view):
raise ValueError("Cannot downsample a WCS with indexing. Use "
"wcs.sub or wcs.dropaxis if you want to remove "
"axes.")
wcs_new = self.deepcopy()
for i, iview in enumerate(view):
if iview.step is not None and iview.step < 0:
raise NotImplementedError("Reversing an axis is not "
"implemented.")
if numpy_order:
wcs_index = self.wcs.naxis - 1 - i
else:
wcs_index = i
if iview.step is not None and iview.start is None:
# Slice from "None" is equivalent to slice from 0 (but one
# might want to downsample, so allow slices with
# None,None,step or None,stop,step)
iview = slice(0, iview.stop, iview.step)
if iview.start is not None:
if iview.step not in (None, 1):
crpix = self.wcs.crpix[wcs_index]
cdelt = self.wcs.cdelt[wcs_index]
# equivalently (keep this comment so you can compare eqns):
# wcs_new.wcs.crpix[wcs_index] =
# (crpix - iview.start)*iview.step + 0.5 - iview.step/2.
crp = ((crpix - iview.start - 1.)/iview.step
+ 0.5 + 1./iview.step/2.)
wcs_new.wcs.crpix[wcs_index] = crp
wcs_new.wcs.cdelt[wcs_index] = cdelt * iview.step
else:
wcs_new.wcs.crpix[wcs_index] -= iview.start
try:
# range requires integers but the other attributes can also
# handle arbitary values, so this needs to be in a try/except.
nitems = len(builtins.range(self._naxis[wcs_index])[iview])
except TypeError as exc:
if 'indices must be integers' not in str(exc):
raise
warnings.warn("NAXIS{0} attribute is not updated because at "
"least one indix ('{1}') is no integer."
"".format(wcs_index, iview), AstropyUserWarning)
else:
wcs_new._naxis[wcs_index] = nitems
return wcs_new
def __getitem__(self, item):
# "getitem" is a shortcut for self.slice; it is very limited
# there is no obvious and unambiguous interpretation of wcs[1,2,3]
# We COULD allow wcs[1] to link to wcs.sub([2])
# (wcs[i] -> wcs.sub([i+1])
return self.slice(item)
def __iter__(self):
# Having __getitem__ makes Python think WCS is iterable. However,
# Python first checks whether __iter__ is present, so we can raise an
# exception here.
raise TypeError("'{0}' object is not iterable".format(self.__class__.__name__))
@property
def axis_type_names(self):
"""
World names for each coordinate axis
Returns
-------
A list of names along each axis
"""
names = list(self.wcs.cname)
types = self.wcs.ctype
for i in range(len(names)):
if len(names[i]) > 0:
continue
names[i] = types[i].split('-')[0]
return names
@property
def celestial(self):
"""
A copy of the current WCS with only the celestial axes included
"""
return self.sub([WCSSUB_CELESTIAL])
@property
def is_celestial(self):
return self.has_celestial and self.naxis == 2
@property
def has_celestial(self):
try:
return self.celestial.naxis == 2
except InconsistentAxisTypesError:
return False
@property
def pixel_scale_matrix(self):
try:
cdelt = np.matrix(np.diag(self.wcs.get_cdelt()))
pc = np.matrix(self.wcs.get_pc())
except InconsistentAxisTypesError:
try:
# for non-celestial axes, get_cdelt doesn't work
cdelt = np.matrix(self.wcs.cd) * np.matrix(np.diag(self.wcs.cdelt))
except AttributeError:
cdelt = np.matrix(np.diag(self.wcs.cdelt))
try:
pc = np.matrix(self.wcs.pc)
except AttributeError:
pc = 1
pccd = np.array(cdelt * pc)
return pccd
def _as_mpl_axes(self):
"""
Compatibility hook for Matplotlib and WCSAxes.
With this method, one can do:
from astropy.wcs import WCS
import matplotlib.pyplot as plt
wcs = WCS('filename.fits')
fig = plt.figure()
ax = fig.add_axes([0.15, 0.1, 0.8, 0.8], projection=wcs)
...
and this will generate a plot with the correct WCS coordinates on the
axes.
"""
from ..visualization.wcsaxes import WCSAxes
return WCSAxes, {'wcs': self}
def __WCS_unpickle__(cls, dct, fits_data):
"""
Unpickles a WCS object from a serialized FITS string.
"""
self = cls.__new__(cls)
self.__dict__.update(dct)
buffer = io.BytesIO(fits_data)
hdulist = fits.open(buffer)
WCS.__init__(self, hdulist[0].header, hdulist)
return self
def find_all_wcs(header, relax=True, keysel=None, fix=True,
translate_units='',
_do_set=True):
"""
Find all the WCS transformations in the given header.
Parameters
----------
header : str or astropy.io.fits header object.
relax : bool or int, optional
Degree of permissiveness:
- `True` (default): Admit all recognized informal extensions of the
WCS standard.
- `False`: Recognize only FITS keywords defined by the
published WCS standard.
- `int`: a bit field selecting specific extensions to accept.
See :ref:`relaxread` for details.
keysel : sequence of flags, optional
A list of flags used to select the keyword types considered by
wcslib. When ``None``, only the standard image header
keywords are considered (and the underlying wcspih() C
function is called). To use binary table image array or pixel
list keywords, *keysel* must be set.
Each element in the list should be one of the following strings:
- 'image': Image header keywords
- 'binary': Binary table image array keywords
- 'pixel': Pixel list keywords
Keywords such as ``EQUIna`` or ``RFRQna`` that are common to
binary table image arrays and pixel lists (including
``WCSNna`` and ``TWCSna``) are selected by both 'binary' and
'pixel'.
fix : bool, optional
When `True` (default), call `~astropy.wcs.Wcsprm.fix` on
the resulting objects to fix any non-standard uses in the
header. `FITSFixedWarning` warnings will be emitted if any
changes were made.
translate_units : str, optional
Specify which potentially unsafe translations of non-standard
unit strings to perform. By default, performs none. See
`WCS.fix` for more information about this parameter. Only
effective when ``fix`` is `True`.
Returns
-------
wcses : list of `WCS` objects
"""
if isinstance(header, (str, bytes)):
header_string = header
elif isinstance(header, fits.Header):
header_string = header.tostring()
else:
raise TypeError(
"header must be a string or astropy.io.fits.Header object")
keysel_flags = _parse_keysel(keysel)
if isinstance(header_string, str):
header_bytes = header_string.encode('ascii')
else:
header_bytes = header_string
wcsprms = _wcs.find_all_wcs(header_bytes, relax, keysel_flags)
result = []
for wcsprm in wcsprms:
subresult = WCS(fix=False, _do_set=False)
subresult.wcs = wcsprm
result.append(subresult)
if fix:
subresult.fix(translate_units)
if _do_set:
subresult.wcs.set()
return result
def validate(source):
"""
Prints a WCS validation report for the given FITS file.
Parameters
----------
source : str path, readable file-like object or `astropy.io.fits.HDUList` object
The FITS file to validate.
Returns
-------
results : WcsValidateResults instance
The result is returned as nested lists. The first level
corresponds to the HDUs in the given file. The next level has
an entry for each WCS found in that header. The special
subclass of list will pretty-print the results as a table when
printed.
"""
class _WcsValidateWcsResult(list):
def __init__(self, key):
self._key = key
def __repr__(self):
result = [" WCS key '{0}':".format(self._key or ' ')]
if len(self):
for entry in self:
for i, line in enumerate(entry.splitlines()):
if i == 0:
initial_indent = ' - '
else:
initial_indent = ' '
result.extend(
textwrap.wrap(
line,
initial_indent=initial_indent,
subsequent_indent=' '))
else:
result.append(" No issues.")
return '\n'.join(result)
class _WcsValidateHduResult(list):
def __init__(self, hdu_index, hdu_name):
self._hdu_index = hdu_index
self._hdu_name = hdu_name
list.__init__(self)
def __repr__(self):
if len(self):
if self._hdu_name:
hdu_name = ' ({0})'.format(self._hdu_name)
else:
hdu_name = ''
result = ['HDU {0}{1}:'.format(self._hdu_index, hdu_name)]
for wcs in self:
result.append(repr(wcs))
return '\n'.join(result)
return ''
class _WcsValidateResults(list):
def __repr__(self):
result = []
for hdu in self:
content = repr(hdu)
if len(content):
result.append(content)
return '\n\n'.join(result)
global __warningregistry__
if isinstance(source, fits.HDUList):
hdulist = source
else:
hdulist = fits.open(source)
results = _WcsValidateResults()
for i, hdu in enumerate(hdulist):
hdu_results = _WcsValidateHduResult(i, hdu.name)
results.append(hdu_results)
with warnings.catch_warnings(record=True) as warning_lines:
wcses = find_all_wcs(
hdu.header, relax=_wcs.WCSHDR_reject,
fix=False, _do_set=False)
for wcs in wcses:
wcs_results = _WcsValidateWcsResult(wcs.wcs.alt)
hdu_results.append(wcs_results)
try:
del __warningregistry__
except NameError:
pass
with warnings.catch_warnings(record=True) as warning_lines:
warnings.resetwarnings()
warnings.simplefilter(
"always", FITSFixedWarning, append=True)
try:
WCS(hdu.header,
key=wcs.wcs.alt or ' ',
relax=_wcs.WCSHDR_reject,
fix=True, _do_set=False)
except WcsError as e:
wcs_results.append(str(e))
wcs_results.extend([str(x.message) for x in warning_lines])
return results
|
b8e6f496bdc83e1cb70f3f25768e7f79529c88fb3b68d172ed4930a098838ea8 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
# It gets to be really tedious to type long docstrings in ANSI C
# syntax (since multi-line string literals are not valid).
# Therefore, the docstrings are written here in doc/docstrings.py,
# which are then converted by setup.py into docstrings.h, which is
# included by pywcs.c
from . import _docutil as __
a = """
``double array[a_order+1][a_order+1]`` Focal plane transformation
matrix.
The `SIP`_ ``A_i_j`` matrix used for pixel to focal plane
transformation.
Its values may be changed in place, but it may not be resized, without
creating a new `~astropy.wcs.Sip` object.
"""
a_order = """
``int`` (read-only) Order of the polynomial (``A_ORDER``).
"""
all_pix2world = """
all_pix2world(pixcrd, origin) -> ``double array[ncoord][nelem]``
Transforms pixel coordinates to world coordinates.
Does the following:
- Detector to image plane correction (if present)
- SIP distortion correction (if present)
- FITS WCS distortion correction (if present)
- wcslib "core" WCS transformation
The first three (the distortion corrections) are done in parallel.
Parameters
----------
pixcrd : double array[ncoord][nelem]
Array of pixel coordinates.
{0}
Returns
-------
world : double array[ncoord][nelem]
Returns an array of world coordinates.
Raises
------
MemoryError
Memory allocation failed.
SingularMatrixError
Linear transformation matrix is singular.
InconsistentAxisTypesError
Inconsistent or unrecognized coordinate axis types.
ValueError
Invalid parameter value.
ValueError
Invalid coordinate transformation parameters.
ValueError
x- and y-coordinate arrays are not the same size.
InvalidTransformError
Invalid coordinate transformation.
InvalidTransformError
Ill-conditioned coordinate transformation parameters.
""".format(__.ORIGIN())
alt = """
``str`` Character code for alternate coordinate descriptions.
For example, the ``"a"`` in keyword names such as ``CTYPEia``. This
is a space character for the primary coordinate description, or one of
the 26 upper-case letters, A-Z.
"""
ap = """
``double array[ap_order+1][ap_order+1]`` Focal plane to pixel
transformation matrix.
The `SIP`_ ``AP_i_j`` matrix used for focal plane to pixel
transformation. Its values may be changed in place, but it may not be
resized, without creating a new `~astropy.wcs.Sip` object.
"""
ap_order = """
``int`` (read-only) Order of the polynomial (``AP_ORDER``).
"""
axis_types = """
``int array[naxis]`` An array of four-digit type codes for each axis.
- First digit (i.e. 1000s):
- 0: Non-specific coordinate type.
- 1: Stokes coordinate.
- 2: Celestial coordinate (including ``CUBEFACE``).
- 3: Spectral coordinate.
- Second digit (i.e. 100s):
- 0: Linear axis.
- 1: Quantized axis (``STOKES``, ``CUBEFACE``).
- 2: Non-linear celestial axis.
- 3: Non-linear spectral axis.
- 4: Logarithmic axis.
- 5: Tabular axis.
- Third digit (i.e. 10s):
- 0: Group number, e.g. lookup table number
- The fourth digit is used as a qualifier depending on the axis type.
- For celestial axes:
- 0: Longitude coordinate.
- 1: Latitude coordinate.
- 2: ``CUBEFACE`` number.
- For lookup tables: the axis number in a multidimensional table.
``CTYPEia`` in ``"4-3"`` form with unrecognized algorithm code will
have its type set to -1 and generate an error.
"""
b = """
``double array[b_order+1][b_order+1]`` Pixel to focal plane
transformation matrix.
The `SIP`_ ``B_i_j`` matrix used for pixel to focal plane
transformation. Its values may be changed in place, but it may not be
resized, without creating a new `~astropy.wcs.Sip` object.
"""
b_order = """
``int`` (read-only) Order of the polynomial (``B_ORDER``).
"""
bounds_check = """
bounds_check(pix2world, world2pix)
Enable/disable bounds checking.
Parameters
----------
pix2world : bool, optional
When `True`, enable bounds checking for the pixel-to-world (p2x)
transformations. Default is `True`.
world2pix : bool, optional
When `True`, enable bounds checking for the world-to-pixel (s2x)
transformations. Default is `True`.
Notes
-----
Note that by default (without calling `bounds_check`) strict bounds
checking is enabled.
"""
bp = """
``double array[bp_order+1][bp_order+1]`` Focal plane to pixel
transformation matrix.
The `SIP`_ ``BP_i_j`` matrix used for focal plane to pixel
transformation. Its values may be changed in place, but it may not be
resized, without creating a new `~astropy.wcs.Sip` object.
"""
bp_order = """
``int`` (read-only) Order of the polynomial (``BP_ORDER``).
"""
cd = """
``double array[naxis][naxis]`` The ``CDi_ja`` linear transformation
matrix.
For historical compatibility, three alternate specifications of the
linear transformations are available in wcslib. The canonical
``PCi_ja`` with ``CDELTia``, ``CDi_ja``, and the deprecated
``CROTAia`` keywords. Although the latter may not formally co-exist
with ``PCi_ja``, the approach here is simply to ignore them if given
in conjunction with ``PCi_ja``.
`~astropy.wcs.Wcsprm.has_pc`, `~astropy.wcs.Wcsprm.has_cd` and
`~astropy.wcs.Wcsprm.has_crota` can be used to determine which of
these alternatives are present in the header.
These alternate specifications of the linear transformation matrix are
translated immediately to ``PCi_ja`` by `~astropy.wcs.Wcsprm.set` and
are nowhere visible to the lower-level routines. In particular,
`~astropy.wcs.Wcsprm.set` resets `~astropy.wcs.Wcsprm.cdelt` to unity
if ``CDi_ja`` is present (and no ``PCi_ja``). If no ``CROTAia`` is
associated with the latitude axis, `~astropy.wcs.Wcsprm.set` reverts
to a unity ``PCi_ja`` matrix.
"""
cdelt = """
``double array[naxis]`` Coordinate increments (``CDELTia``) for each
coord axis.
If a ``CDi_ja`` linear transformation matrix is present, a warning is
raised and `~astropy.wcs.Wcsprm.cdelt` is ignored. The ``CDi_ja``
matrix may be deleted by::
del wcs.wcs.cd
An undefined value is represented by NaN.
"""
cdfix = """
cdfix()
Fix erroneously omitted ``CDi_ja`` keywords.
Sets the diagonal element of the ``CDi_ja`` matrix to unity if all
``CDi_ja`` keywords associated with a given axis were omitted.
According to Paper I, if any ``CDi_ja`` keywords at all are given in a
FITS header then those not given default to zero. This results in a
singular matrix with an intersecting row and column of zeros.
Returns
-------
success : int
Returns ``0`` for success; ``-1`` if no change required.
"""
cel_offset = """
``boolean`` Is there an offset?
If `True`, an offset will be applied to ``(x, y)`` to force ``(x, y) =
(0, 0)`` at the fiducial point, (phi_0, theta_0). Default is `False`.
"""
celfix = """
Translates AIPS-convention celestial projection types, ``-NCP`` and
``-GLS``.
Returns
-------
success : int
Returns ``0`` for success; ``-1`` if no change required.
"""
cname = """
``list of strings`` A list of the coordinate axis names, from
``CNAMEia``.
"""
colax = """
``int array[naxis]`` An array recording the column numbers for each
axis in a pixel list.
"""
colnum = """
``int`` Column of FITS binary table associated with this WCS.
Where the coordinate representation is associated with an image-array
column in a FITS binary table, this property may be used to record the
relevant column number.
It should be set to zero for an image header or pixel list.
"""
compare = """
compare(other, cmp=0, tolerance=0.0)
Compare two Wcsprm objects for equality.
Parameters
----------
other : Wcsprm
The other Wcsprm object to compare to.
cmp : int, optional
A bit field controlling the strictness of the comparison. When 0,
(the default), all fields must be identical.
The following constants may be or'ed together to loosen the
comparison.
- ``WCSCOMPARE_ANCILLARY``: Ignores ancillary keywords that don't
change the WCS transformation, such as ``DATE-OBS`` or
``EQUINOX``.
- ``WCSCOMPARE_TILING``: Ignore integral differences in
``CRPIXja``. This is the 'tiling' condition, where two WCSes
cover different regions of the same map projection and align on
the same map grid.
- ``WCSCOMPARE_CRPIX``: Ignore any differences at all in
``CRPIXja``. The two WCSes cover different regions of the same
map projection but may not align on the same grid map.
Overrides ``WCSCOMPARE_TILING``.
tolerance : float, optional
The amount of tolerance required. For example, for a value of
1e-6, all floating-point values in the objects must be equal to
the first 6 decimal places. The default value of 0.0 implies
exact equality.
Returns
-------
equal : bool
"""
convert = """
convert(array)
Perform the unit conversion on the elements of the given *array*,
returning an array of the same shape.
"""
coord = """
``double array[K_M]...[K_2][K_1][M]`` The tabular coordinate array.
Has the dimensions::
(K_M, ... K_2, K_1, M)
(see `~astropy.wcs.Tabprm.K`) i.e. with the `M` dimension
varying fastest so that the `M` elements of a coordinate vector are
stored contiguously in memory.
"""
copy = """
Creates a deep copy of the WCS object.
"""
cpdis1 = """
`~astropy.wcs.DistortionLookupTable`
The pre-linear transformation distortion lookup table, ``CPDIS1``.
"""
cpdis2 = """
`~astropy.wcs.DistortionLookupTable`
The pre-linear transformation distortion lookup table, ``CPDIS2``.
"""
crder = """
``double array[naxis]`` The random error in each coordinate axis,
``CRDERia``.
An undefined value is represented by NaN.
"""
crota = """
``double array[naxis]`` ``CROTAia`` keyvalues for each coordinate
axis.
For historical compatibility, three alternate specifications of the
linear transformations are available in wcslib. The canonical
``PCi_ja`` with ``CDELTia``, ``CDi_ja``, and the deprecated
``CROTAia`` keywords. Although the latter may not formally co-exist
with ``PCi_ja``, the approach here is simply to ignore them if given
in conjunction with ``PCi_ja``.
`~astropy.wcs.Wcsprm.has_pc`, `~astropy.wcs.Wcsprm.has_cd` and
`~astropy.wcs.Wcsprm.has_crota` can be used to determine which of
these alternatives are present in the header.
These alternate specifications of the linear transformation matrix are
translated immediately to ``PCi_ja`` by `~astropy.wcs.Wcsprm.set` and
are nowhere visible to the lower-level routines. In particular,
`~astropy.wcs.Wcsprm.set` resets `~astropy.wcs.Wcsprm.cdelt` to unity
if ``CDi_ja`` is present (and no ``PCi_ja``). If no ``CROTAia`` is
associated with the latitude axis, `~astropy.wcs.Wcsprm.set` reverts
to a unity ``PCi_ja`` matrix.
"""
crpix = """
``double array[naxis]`` Coordinate reference pixels (``CRPIXja``) for
each pixel axis.
"""
crval = """
``double array[naxis]`` Coordinate reference values (``CRVALia``) for
each coordinate axis.
"""
crval_tabprm = """
``double array[M]`` Index values for the reference pixel for each of
the tabular coord axes.
"""
csyer = """
``double array[naxis]`` The systematic error in the coordinate value
axes, ``CSYERia``.
An undefined value is represented by NaN.
"""
ctype = """
``list of strings[naxis]`` List of ``CTYPEia`` keyvalues.
The `~astropy.wcs.Wcsprm.ctype` keyword values must be in upper case
and there must be zero or one pair of matched celestial axis types,
and zero or one spectral axis.
"""
cubeface = """
``int`` Index into the ``pixcrd`` (pixel coordinate) array for the
``CUBEFACE`` axis.
This is used for quadcube projections where the cube faces are stored
on a separate axis.
The quadcube projections (``TSC``, ``CSC``, ``QSC``) may be
represented in FITS in either of two ways:
- The six faces may be laid out in one plane and numbered as
follows::
0
4 3 2 1 4 3 2
5
Faces 2, 3 and 4 may appear on one side or the other (or both).
The world-to-pixel routines map faces 2, 3 and 4 to the left but
the pixel-to-world routines accept them on either side.
- The ``COBE`` convention in which the six faces are stored in a
three-dimensional structure using a ``CUBEFACE`` axis indexed
from 0 to 5 as above.
These routines support both methods; `~astropy.wcs.Wcsprm.set`
determines which is being used by the presence or absence of a
``CUBEFACE`` axis in `~astropy.wcs.Wcsprm.ctype`.
`~astropy.wcs.Wcsprm.p2s` and `~astropy.wcs.Wcsprm.s2p` translate the
``CUBEFACE`` axis representation to the single plane representation
understood by the lower-level projection routines.
"""
cunit = """
``list of astropy.UnitBase[naxis]`` List of ``CUNITia`` keyvalues as
`astropy.units.UnitBase` instances.
These define the units of measurement of the ``CRVALia``, ``CDELTia``
and ``CDi_ja`` keywords.
As ``CUNITia`` is an optional header keyword,
`~astropy.wcs.Wcsprm.cunit` may be left blank but otherwise is
expected to contain a standard units specification as defined by WCS
Paper I. `~astropy.wcs.Wcsprm.unitfix` is available to translate
commonly used non-standard units specifications but this must be done
as a separate step before invoking `~astropy.wcs.Wcsprm.set`.
For celestial axes, if `~astropy.wcs.Wcsprm.cunit` is not blank,
`~astropy.wcs.Wcsprm.set` uses ``wcsunits`` to parse it and scale
`~astropy.wcs.Wcsprm.cdelt`, `~astropy.wcs.Wcsprm.crval`, and
`~astropy.wcs.Wcsprm.cd` to decimal degrees. It then resets
`~astropy.wcs.Wcsprm.cunit` to ``"deg"``.
For spectral axes, if `~astropy.wcs.Wcsprm.cunit` is not blank,
`~astropy.wcs.Wcsprm.set` uses ``wcsunits`` to parse it and scale
`~astropy.wcs.Wcsprm.cdelt`, `~astropy.wcs.Wcsprm.crval`, and
`~astropy.wcs.Wcsprm.cd` to SI units. It then resets
`~astropy.wcs.Wcsprm.cunit` accordingly.
`~astropy.wcs.Wcsprm.set` ignores `~astropy.wcs.Wcsprm.cunit` for
other coordinate types; `~astropy.wcs.Wcsprm.cunit` may be used to
label coordinate values.
"""
cylfix = """
cylfix()
Fixes WCS keyvalues for malformed cylindrical projections.
Returns
-------
success : int
Returns ``0`` for success; ``-1`` if no change required.
"""
data = """
``float array`` The array data for the
`~astropy.wcs.DistortionLookupTable`.
"""
data_wtbarr = """
``double array``
The array data for the BINTABLE.
"""
dateavg = """
``string`` Representative mid-point of the date of observation.
In ISO format, ``yyyy-mm-ddThh:mm:ss``.
See also
--------
astropy.wcs.Wcsprm.dateobs
"""
dateobs = """
``string`` Start of the date of observation.
In ISO format, ``yyyy-mm-ddThh:mm:ss``.
See also
--------
astropy.wcs.Wcsprm.dateavg
"""
datfix = """
datfix()
Translates the old ``DATE-OBS`` date format to year-2000 standard form
``(yyyy-mm-ddThh:mm:ss)`` and derives ``MJD-OBS`` from it if not
already set.
Alternatively, if `~astropy.wcs.Wcsprm.mjdobs` is set and
`~astropy.wcs.Wcsprm.dateobs` isn't, then `~astropy.wcs.Wcsprm.datfix`
derives `~astropy.wcs.Wcsprm.dateobs` from it. If both are set but
disagree by more than half a day then `ValueError` is raised.
Returns
-------
success : int
Returns ``0`` for success; ``-1`` if no change required.
"""
delta = """
``double array[M]`` (read-only) Interpolated indices into the coord
array.
Array of interpolated indices into the coordinate array such that
Upsilon_m, as defined in Paper III, is equal to
(`~astropy.wcs.Tabprm.p0` [m] + 1) + delta[m].
"""
det2im = """
Convert detector coordinates to image plane coordinates.
"""
det2im1 = """
A `~astropy.wcs.DistortionLookupTable` object for detector to image plane
correction in the *x*-axis.
"""
det2im2 = """
A `~astropy.wcs.DistortionLookupTable` object for detector to image plane
correction in the *y*-axis.
"""
dims = """
``int array[ndim]`` (read-only)
The dimensions of the tabular array
`~astropy.wcs.Wtbarr.data`.
"""
DistortionLookupTable = """
DistortionLookupTable(*table*, *crpix*, *crval*, *cdelt*)
Represents a single lookup table for a `distortion paper`_
transformation.
Parameters
----------
table : 2-dimensional array
The distortion lookup table.
crpix : 2-tuple
The distortion array reference pixel
crval : 2-tuple
The image array pixel coordinate
cdelt : 2-tuple
The grid step size
"""
equinox = """
``double`` The equinox associated with dynamical equatorial or
ecliptic coordinate systems.
``EQUINOXa`` (or ``EPOCH`` in older headers). Not applicable to ICRS
equatorial or ecliptic coordinates.
An undefined value is represented by NaN.
"""
extlev = """
``int`` (read-only)
``EXTLEV`` identifying the binary table extension.
"""
extnam = """
``str`` (read-only)
``EXTNAME`` identifying the binary table extension.
"""
extrema = """
``double array[K_M]...[K_2][2][M]`` (read-only)
An array recording the minimum and maximum value of each element of
the coordinate vector in each row of the coordinate array, with the
dimensions::
(K_M, ... K_2, 2, M)
(see `~astropy.wcs.Tabprm.K`). The minimum is recorded
in the first element of the compressed K_1 dimension, then the
maximum. This array is used by the inverse table lookup function to
speed up table searches.
"""
extver = """
``int`` (read-only)
``EXTVER`` identifying the binary table extension.
"""
find_all_wcs = """
find_all_wcs(relax=0, keysel=0)
Find all WCS transformations in the header.
Parameters
----------
header : str
The raw FITS header data.
relax : bool or int
Degree of permissiveness:
- `False`: Recognize only FITS keywords defined by the published
WCS standard.
- `True`: Admit all recognized informal extensions of the WCS
standard.
- `int`: a bit field selecting specific extensions to accept. See
:ref:`relaxread` for details.
keysel : sequence of flags
Used to restrict the keyword types considered:
- ``WCSHDR_IMGHEAD``: Image header keywords.
- ``WCSHDR_BIMGARR``: Binary table image array.
- ``WCSHDR_PIXLIST``: Pixel list keywords.
If zero, there is no restriction. If -1, `wcspih` is called,
rather than `wcstbh`.
Returns
-------
wcs_list : list of `~astropy.wcs.Wcsprm` objects
"""
fix = """
fix(translate_units='', naxis=0)
Applies all of the corrections handled separately by
`~astropy.wcs.Wcsprm.datfix`, `~astropy.wcs.Wcsprm.unitfix`,
`~astropy.wcs.Wcsprm.celfix`, `~astropy.wcs.Wcsprm.spcfix`,
`~astropy.wcs.Wcsprm.cylfix` and `~astropy.wcs.Wcsprm.cdfix`.
Parameters
----------
translate_units : str, optional
Specify which potentially unsafe translations of non-standard unit
strings to perform. By default, performs all.
Although ``"S"`` is commonly used to represent seconds, its
translation to ``"s"`` is potentially unsafe since the standard
recognizes ``"S"`` formally as Siemens, however rarely that may be
used. The same applies to ``"H"`` for hours (Henry), and ``"D"``
for days (Debye).
This string controls what to do in such cases, and is
case-insensitive.
- If the string contains ``"s"``, translate ``"S"`` to ``"s"``.
- If the string contains ``"h"``, translate ``"H"`` to ``"h"``.
- If the string contains ``"d"``, translate ``"D"`` to ``"d"``.
Thus ``''`` doesn't do any unsafe translations, whereas ``'shd'``
does all of them.
naxis : int array[naxis], optional
Image axis lengths. If this array is set to zero or ``None``,
then `~astropy.wcs.Wcsprm.cylfix` will not be invoked.
Returns
-------
status : dict
Returns a dictionary containing the following keys, each referring
to a status string for each of the sub-fix functions that were
called:
- `~astropy.wcs.Wcsprm.cdfix`
- `~astropy.wcs.Wcsprm.datfix`
- `~astropy.wcs.Wcsprm.unitfix`
- `~astropy.wcs.Wcsprm.celfix`
- `~astropy.wcs.Wcsprm.spcfix`
- `~astropy.wcs.Wcsprm.cylfix`
"""
get_offset = """
get_offset(x, y) -> (x, y)
Returns the offset as defined in the distortion lookup table.
Returns
-------
coordinate : coordinate pair
The offset from the distortion table for pixel point (*x*, *y*).
"""
get_cdelt = """
get_cdelt() -> double array[naxis]
Coordinate increments (``CDELTia``) for each coord axis.
Returns the ``CDELT`` offsets in read-only form. Unlike the
`~astropy.wcs.Wcsprm.cdelt` property, this works even when the header
specifies the linear transformation matrix in one of the alternative
``CDi_ja`` or ``CROTAia`` forms. This is useful when you want access
to the linear transformation matrix, but don't care how it was
specified in the header.
"""
get_pc = """
get_pc() -> double array[naxis][naxis]
Returns the ``PC`` matrix in read-only form. Unlike the
`~astropy.wcs.Wcsprm.pc` property, this works even when the header
specifies the linear transformation matrix in one of the alternative
``CDi_ja`` or ``CROTAia`` forms. This is useful when you want access
to the linear transformation matrix, but don't care how it was
specified in the header.
"""
get_ps = """
get_ps() -> list of tuples
Returns ``PSi_ma`` keywords for each *i* and *m*.
Returns
-------
ps : list of tuples
Returned as a list of tuples of the form (*i*, *m*, *value*):
- *i*: int. Axis number, as in ``PSi_ma``, (i.e. 1-relative)
- *m*: int. Parameter number, as in ``PSi_ma``, (i.e. 0-relative)
- *value*: string. Parameter value.
See also
--------
astropy.wcs.Wcsprm.set_ps : Set ``PSi_ma`` values
"""
get_pv = """
get_pv() -> list of tuples
Returns ``PVi_ma`` keywords for each *i* and *m*.
Returns
-------
Returned as a list of tuples of the form (*i*, *m*, *value*):
- *i*: int. Axis number, as in ``PVi_ma``, (i.e. 1-relative)
- *m*: int. Parameter number, as in ``PVi_ma``, (i.e. 0-relative)
- *value*: string. Parameter value.
See also
--------
astropy.wcs.Wcsprm.set_pv : Set ``PVi_ma`` values
Notes
-----
Note that, if they were not given, `~astropy.wcs.Wcsprm.set` resets
the entries for ``PVi_1a``, ``PVi_2a``, ``PVi_3a``, and ``PVi_4a`` for
longitude axis *i* to match (``phi_0``, ``theta_0``), the native
longitude and latitude of the reference point given by ``LONPOLEa``
and ``LATPOLEa``.
"""
has_cd = """
has_cd() -> bool
Returns `True` if ``CDi_ja`` is present.
``CDi_ja`` is an alternate specification of the linear transformation
matrix, maintained for historical compatibility.
Matrix elements in the IRAF convention are equivalent to the product
``CDi_ja = CDELTia * PCi_ja``, but the defaults differ from that of
the ``PCi_ja`` matrix. If one or more ``CDi_ja`` keywords are present
then all unspecified ``CDi_ja`` default to zero. If no ``CDi_ja`` (or
``CROTAia``) keywords are present, then the header is assumed to be in
``PCi_ja`` form whether or not any ``PCi_ja`` keywords are present
since this results in an interpretation of ``CDELTia`` consistent with
the original FITS specification.
While ``CDi_ja`` may not formally co-exist with ``PCi_ja``, it may
co-exist with ``CDELTia`` and ``CROTAia`` which are to be ignored.
See also
--------
astropy.wcs.Wcsprm.cd : Get the raw ``CDi_ja`` values.
"""
has_cdi_ja = """
has_cdi_ja() -> bool
Alias for `~astropy.wcs.Wcsprm.has_cd`. Maintained for backward
compatibility.
"""
has_crota = """
has_crota() -> bool
Returns `True` if ``CROTAia`` is present.
``CROTAia`` is an alternate specification of the linear transformation
matrix, maintained for historical compatibility.
In the AIPS convention, ``CROTAia`` may only be associated with the
latitude axis of a celestial axis pair. It specifies a rotation in
the image plane that is applied *after* the ``CDELTia``; any other
``CROTAia`` keywords are ignored.
``CROTAia`` may not formally co-exist with ``PCi_ja``. ``CROTAia`` and
``CDELTia`` may formally co-exist with ``CDi_ja`` but if so are to be
ignored.
See also
--------
astropy.wcs.Wcsprm.crota : Get the raw ``CROTAia`` values
"""
has_crotaia = """
has_crotaia() -> bool
Alias for `~astropy.wcs.Wcsprm.has_crota`. Maintained for backward
compatibility.
"""
has_pc = """
has_pc() -> bool
Returns `True` if ``PCi_ja`` is present. ``PCi_ja`` is the
recommended way to specify the linear transformation matrix.
See also
--------
astropy.wcs.Wcsprm.pc : Get the raw ``PCi_ja`` values
"""
has_pci_ja = """
has_pci_ja() -> bool
Alias for `~astropy.wcs.Wcsprm.has_pc`. Maintained for backward
compatibility.
"""
i = """
``int`` (read-only)
Image axis number.
"""
imgpix_matrix = """
``double array[2][2]`` (read-only) Inverse of the ``CDELT`` or ``PC``
matrix.
Inverse containing the product of the ``CDELTia`` diagonal matrix and
the ``PCi_ja`` matrix.
"""
is_unity = """
is_unity() -> bool
Returns `True` if the linear transformation matrix
(`~astropy.wcs.Wcsprm.cd`) is unity.
"""
K = """
``int array[M]`` (read-only) The lengths of the axes of the coordinate
array.
An array of length `M` whose elements record the lengths of the axes of
the coordinate array and of each indexing vector.
"""
kind = """
``str`` (read-only)
Character identifying the wcstab array type:
- ``'c'``: coordinate array,
- ``'i'``: index vector.
"""
lat = """
``int`` (read-only) The index into the world coord array containing
latitude values.
"""
latpole = """
``double`` The native latitude of the celestial pole, ``LATPOLEa`` (deg).
"""
lattyp = """
``string`` (read-only) Celestial axis type for latitude.
For example, "RA", "DEC", "GLON", "GLAT", etc. extracted from "RA--",
"DEC-", "GLON", "GLAT", etc. in the first four characters of
``CTYPEia`` but with trailing dashes removed.
"""
lng = """
``int`` (read-only) The index into the world coord array containing
longitude values.
"""
lngtyp = """
``string`` (read-only) Celestial axis type for longitude.
For example, "RA", "DEC", "GLON", "GLAT", etc. extracted from "RA--",
"DEC-", "GLON", "GLAT", etc. in the first four characters of
``CTYPEia`` but with trailing dashes removed.
"""
lonpole = """
``double`` The native longitude of the celestial pole.
``LONPOLEa`` (deg).
"""
M = """
``int`` (read-only) Number of tabular coordinate axes.
"""
m = """
``int`` (read-only)
Array axis number for index vectors.
"""
map = """
``int array[M]`` Association between axes.
A vector of length `~astropy.wcs.Tabprm.M` that defines
the association between axis *m* in the *M*-dimensional coordinate
array (1 <= *m* <= *M*) and the indices of the intermediate world
coordinate and world coordinate arrays.
When the intermediate and world coordinate arrays contain the full
complement of coordinate elements in image-order, as will usually be
the case, then ``map[m-1] == i-1`` for axis *i* in the *N*-dimensional
image (1 <= *i* <= *N*). In terms of the FITS keywords::
map[PVi_3a - 1] == i - 1.
However, a different association may result if the intermediate
coordinates, for example, only contains a (relevant) subset of
intermediate world coordinate elements. For example, if *M* == 1 for
an image with *N* > 1, it is possible to fill the intermediate
coordinates with the relevant coordinate element with ``nelem`` set to
1. In this case ``map[0] = 0`` regardless of the value of *i*.
"""
mix = """
mix(mixpix, mixcel, vspan, vstep, viter, world, pixcrd, origin)
Given either the celestial longitude or latitude plus an element of
the pixel coordinate, solves for the remaining elements by iterating
on the unknown celestial coordinate element using
`~astropy.wcs.Wcsprm.s2p`.
Parameters
----------
mixpix : int
Which element on the pixel coordinate is given.
mixcel : int
Which element of the celestial coordinate is given. If *mixcel* =
``1``, celestial longitude is given in ``world[self.lng]``,
latitude returned in ``world[self.lat]``. If *mixcel* = ``2``,
celestial latitude is given in ``world[self.lat]``, longitude
returned in ``world[self.lng]``.
vspan : pair of floats
Solution interval for the celestial coordinate, in degrees. The
ordering of the two limits is irrelevant. Longitude ranges may be
specified with any convenient normalization, for example
``(-120,+120)`` is the same as ``(240,480)``, except that the
solution will be returned with the same normalization, i.e. lie
within the interval specified.
vstep : float
Step size for solution search, in degrees. If ``0``, a sensible,
although perhaps non-optimal default will be used.
viter : int
If a solution is not found then the step size will be halved and
the search recommenced. *viter* controls how many times the step
size is halved. The allowed range is 5 - 10.
world : double array[naxis]
World coordinate elements. ``world[self.lng]`` and
``world[self.lat]`` are the celestial longitude and latitude, in
degrees. Which is given and which returned depends on the value
of *mixcel*. All other elements are given. The results will be
written to this array in-place.
pixcrd : double array[naxis].
Pixel coordinates. The element indicated by *mixpix* is given and
the remaining elements will be written in-place.
{0}
Returns
-------
result : dict
Returns a dictionary with the following keys:
- *phi* (double array[naxis])
- *theta* (double array[naxis])
- Longitude and latitude in the native coordinate system of
the projection, in degrees.
- *imgcrd* (double array[naxis])
- Image coordinate elements. ``imgcrd[self.lng]`` and
``imgcrd[self.lat]`` are the projected *x*- and
*y*-coordinates, in decimal degrees.
- *world* (double array[naxis])
- Another reference to the *world* argument passed in.
Raises
------
MemoryError
Memory allocation failed.
SingularMatrixError
Linear transformation matrix is singular.
InconsistentAxisTypesError
Inconsistent or unrecognized coordinate axis types.
ValueError
Invalid parameter value.
InvalidTransformError
Invalid coordinate transformation parameters.
InvalidTransformError
Ill-conditioned coordinate transformation parameters.
InvalidCoordinateError
Invalid world coordinate.
NoSolutionError
No solution found in the specified interval.
See also
--------
astropy.wcs.Wcsprm.lat, astropy.wcs.Wcsprm.lng
Get the axes numbers for latitude and longitude
Notes
-----
Initially, the specified solution interval is checked to see if it's a
\"crossing\" interval. If it isn't, a search is made for a crossing
solution by iterating on the unknown celestial coordinate starting at
the upper limit of the solution interval and decrementing by the
specified step size. A crossing is indicated if the trial value of
the pixel coordinate steps through the value specified. If a crossing
interval is found then the solution is determined by a modified form
of \"regula falsi\" division of the crossing interval. If no crossing
interval was found within the specified solution interval then a
search is made for a \"non-crossing\" solution as may arise from a
point of tangency. The process is complicated by having to make
allowance for the discontinuities that occur in all map projections.
Once one solution has been determined others may be found by
subsequent invocations of `~astropy.wcs.Wcsprm.mix` with suitably
restricted solution intervals.
Note the circumstance that arises when the solution point lies at a
native pole of a projection in which the pole is represented as a
finite curve, for example the zenithals and conics. In such cases two
or more valid solutions may exist but `~astropy.wcs.Wcsprm.mix` only
ever returns one.
Because of its generality, `~astropy.wcs.Wcsprm.mix` is very
compute-intensive. For compute-limited applications, more efficient
special-case solvers could be written for simple projections, for
example non-oblique cylindrical projections.
""".format(__.ORIGIN())
mjdavg = """
``double`` Modified Julian Date corresponding to ``DATE-AVG``.
``(MJD = JD - 2400000.5)``.
An undefined value is represented by NaN.
See also
--------
astropy.wcs.Wcsprm.mjdobs
"""
mjdobs = """
``double`` Modified Julian Date corresponding to ``DATE-OBS``.
``(MJD = JD - 2400000.5)``.
An undefined value is represented by NaN.
See also
--------
astropy.wcs.Wcsprm.mjdavg
"""
name = """
``string`` The name given to the coordinate representation
``WCSNAMEa``.
"""
naxis = """
``int`` (read-only) The number of axes (pixel and coordinate).
Given by the ``NAXIS`` or ``WCSAXESa`` keyvalues.
The number of coordinate axes is determined at parsing time, and can
not be subsequently changed.
It is determined from the highest of the following:
1. ``NAXIS``
2. ``WCSAXESa``
3. The highest axis number in any parameterized WCS keyword. The
keyvalue, as well as the keyword, must be syntactically valid
otherwise it will not be considered.
If none of these keyword types is present, i.e. if the header only
contains auxiliary WCS keywords for a particular coordinate
representation, then no coordinate description is constructed for it.
This value may differ for different coordinate representations of the
same image.
"""
nc = """
``int`` (read-only) Total number of coord vectors in the coord array.
Total number of coordinate vectors in the coordinate array being the
product K_1 * K_2 * ... * K_M.
"""
ndim = """
``int`` (read-only)
Expected dimensionality of the wcstab array.
"""
obsgeo = """
``double array[3]`` Location of the observer in a standard terrestrial
reference frame.
``OBSGEO-X``, ``OBSGEO-Y``, ``OBSGEO-Z`` (in meters).
An undefined value is represented by NaN.
"""
p0 = """
``int array[M]`` Interpolated indices into the coordinate array.
Vector of length `~astropy.wcs.Tabprm.M` of interpolated
indices into the coordinate array such that Upsilon_m, as defined in
Paper III, is equal to ``(p0[m] + 1) + delta[m]``.
"""
p2s = """
p2s(pixcrd, origin)
Converts pixel to world coordinates.
Parameters
----------
pixcrd : double array[ncoord][nelem]
Array of pixel coordinates.
{0}
Returns
-------
result : dict
Returns a dictionary with the following keys:
- *imgcrd*: double array[ncoord][nelem]
- Array of intermediate world coordinates. For celestial axes,
``imgcrd[][self.lng]`` and ``imgcrd[][self.lat]`` are the
projected *x*-, and *y*-coordinates, in pseudo degrees. For
spectral axes, ``imgcrd[][self.spec]`` is the intermediate
spectral coordinate, in SI units.
- *phi*: double array[ncoord]
- *theta*: double array[ncoord]
- Longitude and latitude in the native coordinate system of the
projection, in degrees.
- *world*: double array[ncoord][nelem]
- Array of world coordinates. For celestial axes,
``world[][self.lng]`` and ``world[][self.lat]`` are the
celestial longitude and latitude, in degrees. For spectral
axes, ``world[][self.spec]`` is the intermediate spectral
coordinate, in SI units.
- *stat*: int array[ncoord]
- Status return value for each coordinate. ``0`` for success,
``1+`` for invalid pixel coordinate.
Raises
------
MemoryError
Memory allocation failed.
SingularMatrixError
Linear transformation matrix is singular.
InconsistentAxisTypesError
Inconsistent or unrecognized coordinate axis types.
ValueError
Invalid parameter value.
ValueError
*x*- and *y*-coordinate arrays are not the same size.
InvalidTransformError
Invalid coordinate transformation parameters.
InvalidTransformError
Ill-conditioned coordinate transformation parameters.
See also
--------
astropy.wcs.Wcsprm.lat, astropy.wcs.Wcsprm.lng
Definition of the latitude and longitude axes
""".format(__.ORIGIN())
p4_pix2foc = """
p4_pix2foc(*pixcrd, origin*) -> double array[ncoord][nelem]
Convert pixel coordinates to focal plane coordinates using `distortion
paper`_ lookup-table correction.
Parameters
----------
pixcrd : double array[ncoord][nelem].
Array of pixel coordinates.
{0}
Returns
-------
foccrd : double array[ncoord][nelem]
Returns an array of focal plane coordinates.
Raises
------
MemoryError
Memory allocation failed.
ValueError
Invalid coordinate transformation parameters.
""".format(__.ORIGIN())
pc = """
``double array[naxis][naxis]`` The ``PCi_ja`` (pixel coordinate)
transformation matrix.
The order is::
[[PC1_1, PC1_2],
[PC2_1, PC2_2]]
For historical compatibility, three alternate specifications of the
linear transformations are available in wcslib. The canonical
``PCi_ja`` with ``CDELTia``, ``CDi_ja``, and the deprecated
``CROTAia`` keywords. Although the latter may not formally co-exist
with ``PCi_ja``, the approach here is simply to ignore them if given
in conjunction with ``PCi_ja``.
`~astropy.wcs.Wcsprm.has_pc`, `~astropy.wcs.Wcsprm.has_cd` and
`~astropy.wcs.Wcsprm.has_crota` can be used to determine which of
these alternatives are present in the header.
These alternate specifications of the linear transformation matrix are
translated immediately to ``PCi_ja`` by `~astropy.wcs.Wcsprm.set` and
are nowhere visible to the lower-level routines. In particular,
`~astropy.wcs.Wcsprm.set` resets `~astropy.wcs.Wcsprm.cdelt` to unity
if ``CDi_ja`` is present (and no ``PCi_ja``). If no ``CROTAia`` is
associated with the latitude axis, `~astropy.wcs.Wcsprm.set` reverts
to a unity ``PCi_ja`` matrix.
"""
phi0 = """
``double`` The native latitude of the fiducial point.
The point whose celestial coordinates are given in ``ref[1:2]``. If
undefined (NaN) the initialization routine, `~astropy.wcs.Wcsprm.set`,
will set this to a projection-specific default.
See also
--------
astropy.wcs.Wcsprm.theta0
"""
pix2foc = """
pix2foc(*pixcrd, origin*) -> double array[ncoord][nelem]
Perform both `SIP`_ polynomial and `distortion paper`_ lookup-table
correction in parallel.
Parameters
----------
pixcrd : double array[ncoord][nelem]
Array of pixel coordinates.
{0}
Returns
-------
foccrd : double array[ncoord][nelem]
Returns an array of focal plane coordinates.
Raises
------
MemoryError
Memory allocation failed.
ValueError
Invalid coordinate transformation parameters.
""".format(__.ORIGIN())
piximg_matrix = """
``double array[2][2]`` (read-only) Matrix containing the product of
the ``CDELTia`` diagonal matrix and the ``PCi_ja`` matrix.
"""
print_contents = """
print_contents()
Print the contents of the `~astropy.wcs.Wcsprm` object to stdout.
Probably only useful for debugging purposes, and may be removed in the
future.
To get a string of the contents, use `repr`.
"""
print_contents_tabprm = """
print_contents()
Print the contents of the `~astropy.wcs.Tabprm` object to
stdout. Probably only useful for debugging purposes, and may be
removed in the future.
To get a string of the contents, use `repr`.
"""
radesys = """
``string`` The equatorial or ecliptic coordinate system type,
``RADESYSa``.
"""
restfrq = """
``double`` Rest frequency (Hz) from ``RESTFRQa``.
An undefined value is represented by NaN.
"""
restwav = """
``double`` Rest wavelength (m) from ``RESTWAVa``.
An undefined value is represented by NaN.
"""
row = """
``int`` (read-only)
Table row number.
"""
s2p = """
s2p(world, origin)
Transforms world coordinates to pixel coordinates.
Parameters
----------
world : double array[ncoord][nelem]
Array of world coordinates, in decimal degrees.
{0}
Returns
-------
result : dict
Returns a dictionary with the following keys:
- *phi*: double array[ncoord]
- *theta*: double array[ncoord]
- Longitude and latitude in the native coordinate system of
the projection, in degrees.
- *imgcrd*: double array[ncoord][nelem]
- Array of intermediate world coordinates. For celestial axes,
``imgcrd[][self.lng]`` and ``imgcrd[][self.lat]`` are the
projected *x*-, and *y*-coordinates, in pseudo \"degrees\".
For quadcube projections with a ``CUBEFACE`` axis, the face
number is also returned in ``imgcrd[][self.cubeface]``. For
spectral axes, ``imgcrd[][self.spec]`` is the intermediate
spectral coordinate, in SI units.
- *pixcrd*: double array[ncoord][nelem]
- Array of pixel coordinates. Pixel coordinates are
zero-based.
- *stat*: int array[ncoord]
- Status return value for each coordinate. ``0`` for success,
``1+`` for invalid pixel coordinate.
Raises
------
MemoryError
Memory allocation failed.
SingularMatrixError
Linear transformation matrix is singular.
InconsistentAxisTypesError
Inconsistent or unrecognized coordinate axis types.
ValueError
Invalid parameter value.
InvalidTransformError
Invalid coordinate transformation parameters.
InvalidTransformError
Ill-conditioned coordinate transformation parameters.
See also
--------
astropy.wcs.Wcsprm.lat, astropy.wcs.Wcsprm.lng
Definition of the latitude and longitude axes
""".format(__.ORIGIN())
sense = """
``int array[M]`` +1 if monotonically increasing, -1 if decreasing.
A vector of length `~astropy.wcs.Tabprm.M` whose elements
indicate whether the corresponding indexing vector is monotonically
increasing (+1), or decreasing (-1).
"""
set = """
set()
Sets up a WCS object for use according to information supplied within
it.
Note that this routine need not be called directly; it will be invoked
by `~astropy.wcs.Wcsprm.p2s` and `~astropy.wcs.Wcsprm.s2p` if
necessary.
Some attributes that are based on other attributes (such as
`~astropy.wcs.Wcsprm.lattyp` on `~astropy.wcs.Wcsprm.ctype`) may not
be correct until after `~astropy.wcs.Wcsprm.set` is called.
`~astropy.wcs.Wcsprm.set` strips off trailing blanks in all string
members.
`~astropy.wcs.Wcsprm.set` recognizes the ``NCP`` projection and
converts it to the equivalent ``SIN`` projection and it also
recognizes ``GLS`` as a synonym for ``SFL``. It does alias
translation for the AIPS spectral types (``FREQ-LSR``, ``FELO-HEL``,
etc.) but without changing the input header keywords.
Raises
------
MemoryError
Memory allocation failed.
SingularMatrixError
Linear transformation matrix is singular.
InconsistentAxisTypesError
Inconsistent or unrecognized coordinate axis types.
ValueError
Invalid parameter value.
InvalidTransformError
Invalid coordinate transformation parameters.
InvalidTransformError
Ill-conditioned coordinate transformation parameters.
"""
set_tabprm = """
set()
Allocates memory for work arrays.
Also sets up the class according to information supplied within it.
Note that this routine need not be called directly; it will be invoked
by functions that need it.
Raises
------
MemoryError
Memory allocation failed.
InvalidTabularParameters
Invalid tabular parameters.
"""
set_ps = """
set_ps(ps)
Sets ``PSi_ma`` keywords for each *i* and *m*.
Parameters
----------
ps : sequence of tuples
The input must be a sequence of tuples of the form (*i*, *m*,
*value*):
- *i*: int. Axis number, as in ``PSi_ma``, (i.e. 1-relative)
- *m*: int. Parameter number, as in ``PSi_ma``, (i.e. 0-relative)
- *value*: string. Parameter value.
See also
--------
astropy.wcs.Wcsprm.get_ps
"""
set_pv = """
set_pv(pv)
Sets ``PVi_ma`` keywords for each *i* and *m*.
Parameters
----------
pv : list of tuples
The input must be a sequence of tuples of the form (*i*, *m*,
*value*):
- *i*: int. Axis number, as in ``PVi_ma``, (i.e. 1-relative)
- *m*: int. Parameter number, as in ``PVi_ma``, (i.e. 0-relative)
- *value*: float. Parameter value.
See also
--------
astropy.wcs.Wcsprm.get_pv
"""
sip = """
Get/set the `~astropy.wcs.Sip` object for performing `SIP`_ distortion
correction.
"""
Sip = """
Sip(*a, b, ap, bp, crpix*)
The `~astropy.wcs.Sip` class performs polynomial distortion correction
using the `SIP`_ convention in both directions.
Parameters
----------
a : double array[m+1][m+1]
The ``A_i_j`` polynomial for pixel to focal plane transformation.
Its size must be (*m* + 1, *m* + 1) where *m* = ``A_ORDER``.
b : double array[m+1][m+1]
The ``B_i_j`` polynomial for pixel to focal plane transformation.
Its size must be (*m* + 1, *m* + 1) where *m* = ``B_ORDER``.
ap : double array[m+1][m+1]
The ``AP_i_j`` polynomial for pixel to focal plane transformation.
Its size must be (*m* + 1, *m* + 1) where *m* = ``AP_ORDER``.
bp : double array[m+1][m+1]
The ``BP_i_j`` polynomial for pixel to focal plane transformation.
Its size must be (*m* + 1, *m* + 1) where *m* = ``BP_ORDER``.
crpix : double array[2]
The reference pixel.
Notes
-----
Shupe, D. L., M. Moshir, J. Li, D. Makovoz and R. Narron. 2005.
"The SIP Convention for Representing Distortion in FITS Image
Headers." ADASS XIV.
"""
sip_foc2pix = """
sip_foc2pix(*foccrd, origin*) -> double array[ncoord][nelem]
Convert focal plane coordinates to pixel coordinates using the `SIP`_
polynomial distortion convention.
Parameters
----------
foccrd : double array[ncoord][nelem]
Array of focal plane coordinates.
{0}
Returns
-------
pixcrd : double array[ncoord][nelem]
Returns an array of pixel coordinates.
Raises
------
MemoryError
Memory allocation failed.
ValueError
Invalid coordinate transformation parameters.
""".format(__.ORIGIN())
sip_pix2foc = """
sip_pix2foc(*pixcrd, origin*) -> double array[ncoord][nelem]
Convert pixel coordinates to focal plane coordinates using the `SIP`_
polynomial distortion convention.
Parameters
----------
pixcrd : double array[ncoord][nelem]
Array of pixel coordinates.
{0}
Returns
-------
foccrd : double array[ncoord][nelem]
Returns an array of focal plane coordinates.
Raises
------
MemoryError
Memory allocation failed.
ValueError
Invalid coordinate transformation parameters.
""".format(__.ORIGIN())
spcfix = """
spcfix() -> int
Translates AIPS-convention spectral coordinate types. {``FREQ``,
``VELO``, ``FELO``}-{``OBS``, ``HEL``, ``LSR``} (e.g. ``FREQ-LSR``,
``VELO-OBS``, ``FELO-HEL``)
Returns
-------
success : int
Returns ``0`` for success; ``-1`` if no change required.
"""
spec = """
``int`` (read-only) The index containing the spectral axis values.
"""
specsys = """
``string`` Spectral reference frame (standard of rest), ``SPECSYSa``.
See also
--------
astropy.wcs.Wcsprm.ssysobs, astropy.wcs.Wcsprm.velosys
"""
sptr = """
sptr(ctype, i=-1)
Translates the spectral axis in a WCS object.
For example, a ``FREQ`` axis may be translated into ``ZOPT-F2W`` and
vice versa.
Parameters
----------
ctype : str
Required spectral ``CTYPEia``, maximum of 8 characters. The first
four characters are required to be given and are never modified.
The remaining four, the algorithm code, are completely determined
by, and must be consistent with, the first four characters.
Wildcarding may be used, i.e. if the final three characters are
specified as ``\"???\"``, or if just the eighth character is
specified as ``\"?\"``, the correct algorithm code will be
substituted and returned.
i : int
Index of the spectral axis (0-relative). If ``i < 0`` (or not
provided), it will be set to the first spectral axis identified
from the ``CTYPE`` keyvalues in the FITS header.
Raises
------
MemoryError
Memory allocation failed.
SingularMatrixError
Linear transformation matrix is singular.
InconsistentAxisTypesError
Inconsistent or unrecognized coordinate axis types.
ValueError
Invalid parameter value.
InvalidTransformError
Invalid coordinate transformation parameters.
InvalidTransformError
Ill-conditioned coordinate transformation parameters.
InvalidSubimageSpecificationError
Invalid subimage specification (no spectral axis).
"""
ssysobs = """
``string`` Spectral reference frame.
The spectral reference frame in which there is no differential
variation in the spectral coordinate across the field-of-view,
``SSYSOBSa``.
See also
--------
astropy.wcs.Wcsprm.specsys, astropy.wcs.Wcsprm.velosys
"""
ssyssrc = """
``string`` Spectral reference frame for redshift.
The spectral reference frame (standard of rest) in which the redshift
was measured, ``SSYSSRCa``.
"""
sub = """
sub(axes)
Extracts the coordinate description for a subimage from a
`~astropy.wcs.WCS` object.
The world coordinate system of the subimage must be separable in the
sense that the world coordinates at any point in the subimage must
depend only on the pixel coordinates of the axes extracted. In
practice, this means that the ``PCi_ja`` matrix of the original image
must not contain non-zero off-diagonal terms that associate any of the
subimage axes with any of the non-subimage axes.
`sub` can also add axes to a wcsprm object. The new axes will be
created using the defaults set by the Wcsprm constructor which produce
a simple, unnamed, linear axis with world coordinates equal to the
pixel coordinate. These default values can be changed before
invoking `set`.
Parameters
----------
axes : int or a sequence.
- If an int, include the first *N* axes in their original order.
- If a sequence, may contain a combination of image axis numbers
(1-relative) or special axis identifiers (see below). Order is
significant; ``axes[0]`` is the axis number of the input image
that corresponds to the first axis in the subimage, etc. Use an
axis number of 0 to create a new axis using the defaults.
- If ``0``, ``[]`` or ``None``, do a deep copy.
Coordinate axes types may be specified using either strings or
special integer constants. The available types are:
- ``'longitude'`` / ``WCSSUB_LONGITUDE``: Celestial longitude
- ``'latitude'`` / ``WCSSUB_LATITUDE``: Celestial latitude
- ``'cubeface'`` / ``WCSSUB_CUBEFACE``: Quadcube ``CUBEFACE`` axis
- ``'spectral'`` / ``WCSSUB_SPECTRAL``: Spectral axis
- ``'stokes'`` / ``WCSSUB_STOKES``: Stokes axis
- ``'celestial'`` / ``WCSSUB_CELESTIAL``: An alias for the
combination of ``'longitude'``, ``'latitude'`` and ``'cubeface'``.
Returns
-------
new_wcs : `~astropy.wcs.WCS` object
Raises
------
MemoryError
Memory allocation failed.
InvalidSubimageSpecificationError
Invalid subimage specification (no spectral axis).
NonseparableSubimageCoordinateSystem
Non-separable subimage coordinate system.
Notes
-----
Combinations of subimage axes of particular types may be extracted in
the same order as they occur in the input image by combining the
integer constants with the 'binary or' (``|``) operator. For
example::
wcs.sub([WCSSUB_LONGITUDE | WCSSUB_LATITUDE | WCSSUB_SPECTRAL])
would extract the longitude, latitude, and spectral axes in the same
order as the input image. If one of each were present, the resulting
object would have three dimensions.
For convenience, ``WCSSUB_CELESTIAL`` is defined as the combination
``WCSSUB_LONGITUDE | WCSSUB_LATITUDE | WCSSUB_CUBEFACE``.
The codes may also be negated to extract all but the types specified,
for example::
wcs.sub([
WCSSUB_LONGITUDE,
WCSSUB_LATITUDE,
WCSSUB_CUBEFACE,
-(WCSSUB_SPECTRAL | WCSSUB_STOKES)])
The last of these specifies all axis types other than spectral or
Stokes. Extraction is done in the order specified by ``axes``, i.e. a
longitude axis (if present) would be extracted first (via ``axes[0]``)
and not subsequently (via ``axes[3]``). Likewise for the latitude and
cubeface axes in this example.
The number of dimensions in the returned object may be less than or
greater than the length of ``axes``. However, it will never exceed the
number of axes in the input image.
"""
tab = """
``list of Tabprm`` Tabular coordinate objects.
A list of tabular coordinate objects associated with this WCS.
"""
Tabprm = """
A class to store the information related to tabular coordinates,
i.e., coordinates that are defined via a lookup table.
This class can not be constructed directly from Python, but instead is
returned from `~astropy.wcs.Wcsprm.tab`.
"""
theta0 = """
``double`` The native longitude of the fiducial point.
The point whose celestial coordinates are given in ``ref[1:2]``. If
undefined (NaN) the initialization routine, `~astropy.wcs.Wcsprm.set`,
will set this to a projection-specific default.
See also
--------
astropy.wcs.Wcsprm.phi0
"""
to_header = """
to_header(relax=False)
`to_header` translates a WCS object into a FITS header.
The details of the header depends on context:
- If the `~astropy.wcs.Wcsprm.colnum` member is non-zero then a
binary table image array header will be produced.
- Otherwise, if the `~astropy.wcs.Wcsprm.colax` member is set
non-zero then a pixel list header will be produced.
- Otherwise, a primary image or image extension header will be
produced.
The output header will almost certainly differ from the input in a
number of respects:
1. The output header only contains WCS-related keywords. In
particular, it does not contain syntactically-required keywords
such as ``SIMPLE``, ``NAXIS``, ``BITPIX``, or ``END``.
2. Deprecated (e.g. ``CROTAn``) or non-standard usage will be
translated to standard (this is partially dependent on whether
``fix`` was applied).
3. Quantities will be converted to the units used internally,
basically SI with the addition of degrees.
4. Floating-point quantities may be given to a different decimal
precision.
5. Elements of the ``PCi_j`` matrix will be written if and only if
they differ from the unit matrix. Thus, if the matrix is unity
then no elements will be written.
6. Additional keywords such as ``WCSAXES``, ``CUNITia``,
``LONPOLEa`` and ``LATPOLEa`` may appear.
7. The original keycomments will be lost, although
`~astropy.wcs.Wcsprm.to_header` tries hard to write meaningful
comments.
8. Keyword order may be changed.
Keywords can be translated between the image array, binary table, and
pixel lists forms by manipulating the `~astropy.wcs.Wcsprm.colnum` or
`~astropy.wcs.Wcsprm.colax` members of the `~astropy.wcs.WCS`
object.
Parameters
----------
relax : bool or int
Degree of permissiveness:
- `False`: Recognize only FITS keywords defined by the published
WCS standard.
- `True`: Admit all recognized informal extensions of the WCS
standard.
- `int`: a bit field selecting specific extensions to write.
See :ref:`relaxwrite` for details.
Returns
-------
header : str
Raw FITS header as a string.
"""
ttype = """
``str`` (read-only)
``TTYPEn`` identifying the column of the binary table that contains
the wcstab array.
"""
unitfix = """
unitfix(translate_units='')
Translates non-standard ``CUNITia`` keyvalues.
For example, ``DEG`` -> ``deg``, also stripping off unnecessary
whitespace.
Parameters
----------
translate_units : str, optional
Do potentially unsafe translations of non-standard unit strings.
Although ``\"S\"`` is commonly used to represent seconds, its
recognizes ``\"S\"`` formally as Siemens, however rarely that may
be translation to ``\"s\"`` is potentially unsafe since the
standard used. The same applies to ``\"H\"`` for hours (Henry),
and ``\"D\"`` for days (Debye).
This string controls what to do in such cases, and is
case-insensitive.
- If the string contains ``\"s\"``, translate ``\"S\"`` to ``\"s\"``.
- If the string contains ``\"h\"``, translate ``\"H\"`` to ``\"h\"``.
- If the string contains ``\"d\"``, translate ``\"D\"`` to ``\"d\"``.
Thus ``''`` doesn't do any unsafe translations, whereas ``'shd'``
does all of them.
Returns
-------
success : int
Returns ``0`` for success; ``-1`` if no change required.
"""
velangl = """
``double`` Velocity angle.
The angle in degrees that should be used to decompose an observed
velocity into radial and transverse components.
An undefined value is represented by NaN.
"""
velosys = """
``double`` Relative radial velocity.
The relative radial velocity (m/s) between the observer and the
selected standard of rest in the direction of the celestial reference
coordinate, ``VELOSYSa``.
An undefined value is represented by NaN.
See also
--------
astropy.wcs.Wcsprm.specsys, astropy.wcs.Wcsprm.ssysobs
"""
velref = """
``int`` AIPS velocity code.
From ``VELREF`` keyword.
"""
wcs = """
A `~astropy.wcs.Wcsprm` object to perform the basic `wcslib`_ WCS
transformation.
"""
Wcs = """
Wcs(*sip, cpdis, wcsprm, det2im*)
Wcs objects amalgamate basic WCS (as provided by `wcslib`_), with
`SIP`_ and `distortion paper`_ operations.
To perform all distortion corrections and WCS transformation, use
``all_pix2world``.
Parameters
----------
sip : `~astropy.wcs.Sip` object or `None`
cpdis : A pair of `~astropy.wcs.DistortionLookupTable` objects, or
``(None, None)``.
wcsprm : `~astropy.wcs.Wcsprm` object
det2im : A pair of `~astropy.wcs.DistortionLookupTable` objects, or
``(None, None)``.
"""
Wcsprm = """
Wcsprm(header=None, key=' ', relax=False, naxis=2, keysel=0, colsel=None)
`~astropy.wcs.Wcsprm` performs the core WCS transformations.
.. note::
The members of this object correspond roughly to the key/value
pairs in the FITS header. However, they are adjusted and
normalized in a number of ways that make performing the WCS
transformation easier. Therefore, they can not be relied upon to
get the original values in the header. For that, use
`astropy.io.fits.Header` directly.
The FITS header parsing enforces correct FITS "keyword = value" syntax
with regard to the equals sign occurring in columns 9 and 10.
However, it does recognize free-format character (NOST 100-2.0,
Sect. 5.2.1), integer (Sect. 5.2.3), and floating-point values
(Sect. 5.2.4) for all keywords.
Parameters
----------
header : An `astropy.io.fits.Header`, string, or `None`.
If ``None``, the object will be initialized to default values.
key : str, optional
The key referring to a particular WCS transform in the header.
This may be either ``' '`` or ``'A'``-``'Z'`` and corresponds to
the ``\"a\"`` part of ``\"CTYPEia\"``. (*key* may only be
provided if *header* is also provided.)
relax : bool or int, optional
Degree of permissiveness:
- `False`: Recognize only FITS keywords defined by the published
WCS standard.
- `True`: Admit all recognized informal extensions of the WCS
standard.
- `int`: a bit field selecting specific extensions to accept. See
:ref:`relaxread` for details.
naxis : int, optional
The number of world coordinates axes for the object. (*naxis* may
only be provided if *header* is `None`.)
keysel : sequence of flag bits, optional
Vector of flag bits that may be used to restrict the keyword types
considered:
- ``WCSHDR_IMGHEAD``: Image header keywords.
- ``WCSHDR_BIMGARR``: Binary table image array.
- ``WCSHDR_PIXLIST``: Pixel list keywords.
If zero, there is no restriction. If -1, the underlying wcslib
function ``wcspih()`` is called, rather than ``wcstbh()``.
colsel : sequence of int
A sequence of table column numbers used to restrict the keywords
considered. `None` indicates no restriction.
Raises
------
MemoryError
Memory allocation failed.
ValueError
Invalid key.
KeyError
Key not found in FITS header.
"""
Wtbarr = """
Classes to construct coordinate lookup tables from a binary table
extension (BINTABLE).
This class can not be constructed directly from Python, but instead is
returned from `~astropy.wcs.Wcsprm.wtb`.
"""
zsource = """
``double`` The redshift, ``ZSOURCEa``, of the source.
An undefined value is represented by NaN.
"""
WcsError = """
Base class of all invalid WCS errors.
"""
SingularMatrix = """
SingularMatrixError()
The linear transformation matrix is singular.
"""
InconsistentAxisTypes = """
InconsistentAxisTypesError()
The WCS header inconsistent or unrecognized coordinate axis type(s).
"""
InvalidTransform = """
InvalidTransformError()
The WCS transformation is invalid, or the transformation parameters
are invalid.
"""
InvalidCoordinate = """
InvalidCoordinateError()
One or more of the world coordinates is invalid.
"""
NoSolution = """
NoSolutionError()
No solution can be found in the given interval.
"""
InvalidSubimageSpecification = """
InvalidSubimageSpecificationError()
The subimage specification is invalid.
"""
NonseparableSubimageCoordinateSystem = """
NonseparableSubimageCoordinateSystemError()
Non-separable subimage coordinate system.
"""
NoWcsKeywordsFound = """
NoWcsKeywordsFoundError()
No WCS keywords were found in the given header.
"""
InvalidTabularParameters = """
InvalidTabularParametersError()
The given tabular parameters are invalid.
"""
|
50bf4573c518b9a1b1ab74cd7341b285efbd06f2fef45f2395a3af90ca47e715 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
The astropy.time package provides functionality for manipulating times and
dates. Specific emphasis is placed on supporting time scales (e.g. UTC, TAI,
UT1) and time representations (e.g. JD, MJD, ISO 8601) that are used in
astronomy.
"""
import copy
import operator
from datetime import datetime
import numpy as np
from ..utils.compat import NUMPY_LT_1_11_2
from .. import units as u, constants as const
from .. import _erfa as erfa
from ..units import UnitConversionError
from ..utils import ShapedLikeNDArray
from ..utils.compat.misc import override__dir__
from ..utils.data_info import MixinInfo, data_info_factory
from .utils import day_frac
from .formats import (TIME_FORMATS, TIME_DELTA_FORMATS,
TimeJD, TimeUnique, TimeAstropyTime, TimeDatetime)
# Import TimeFromEpoch to avoid breaking code that followed the old example of
# making a custom timescale in the documentation.
from .formats import TimeFromEpoch # pylint: disable=W0611
__all__ = ['Time', 'TimeDelta', 'TIME_SCALES', 'TIME_DELTA_SCALES',
'ScaleValueError', 'OperandTypeError', 'TimeInfo']
TIME_SCALES = ('tai', 'tcb', 'tcg', 'tdb', 'tt', 'ut1', 'utc')
MULTI_HOPS = {('tai', 'tcb'): ('tt', 'tdb'),
('tai', 'tcg'): ('tt',),
('tai', 'ut1'): ('utc',),
('tai', 'tdb'): ('tt',),
('tcb', 'tcg'): ('tdb', 'tt'),
('tcb', 'tt'): ('tdb',),
('tcb', 'ut1'): ('tdb', 'tt', 'tai', 'utc'),
('tcb', 'utc'): ('tdb', 'tt', 'tai'),
('tcg', 'tdb'): ('tt',),
('tcg', 'ut1'): ('tt', 'tai', 'utc'),
('tcg', 'utc'): ('tt', 'tai'),
('tdb', 'ut1'): ('tt', 'tai', 'utc'),
('tdb', 'utc'): ('tt', 'tai'),
('tt', 'ut1'): ('tai', 'utc'),
('tt', 'utc'): ('tai',),
}
GEOCENTRIC_SCALES = ('tai', 'tt', 'tcg')
BARYCENTRIC_SCALES = ('tcb', 'tdb')
ROTATIONAL_SCALES = ('ut1',)
TIME_DELTA_TYPES = dict((scale, scales)
for scales in (GEOCENTRIC_SCALES, BARYCENTRIC_SCALES,
ROTATIONAL_SCALES) for scale in scales)
TIME_DELTA_SCALES = TIME_DELTA_TYPES.keys()
# For time scale changes, we need L_G and L_B, which are stored in erfam.h as
# /* L_G = 1 - d(TT)/d(TCG) */
# define ERFA_ELG (6.969290134e-10)
# /* L_B = 1 - d(TDB)/d(TCB), and TDB (s) at TAI 1977/1/1.0 */
# define ERFA_ELB (1.550519768e-8)
# These are exposed in erfa as erfa.ELG and erfa.ELB.
# Implied: d(TT)/d(TCG) = 1-L_G
# and d(TCG)/d(TT) = 1/(1-L_G) = 1 + (1-(1-L_G))/(1-L_G) = 1 + L_G/(1-L_G)
# scale offsets as second = first + first * scale_offset[(first,second)]
SCALE_OFFSETS = {('tt', 'tai'): None,
('tai', 'tt'): None,
('tcg', 'tt'): -erfa.ELG,
('tt', 'tcg'): erfa.ELG / (1. - erfa.ELG),
('tcg', 'tai'): -erfa.ELG,
('tai', 'tcg'): erfa.ELG / (1. - erfa.ELG),
('tcb', 'tdb'): -erfa.ELB,
('tdb', 'tcb'): erfa.ELB / (1. - erfa.ELB)}
# triple-level dictionary, yay!
SIDEREAL_TIME_MODELS = {
'mean': {
'IAU2006': {'function': erfa.gmst06, 'scales': ('ut1', 'tt')},
'IAU2000': {'function': erfa.gmst00, 'scales': ('ut1', 'tt')},
'IAU1982': {'function': erfa.gmst82, 'scales': ('ut1',)}},
'apparent': {
'IAU2006A': {'function': erfa.gst06a, 'scales': ('ut1', 'tt')},
'IAU2000A': {'function': erfa.gst00a, 'scales': ('ut1', 'tt')},
'IAU2000B': {'function': erfa.gst00b, 'scales': ('ut1',)},
'IAU1994': {'function': erfa.gst94, 'scales': ('ut1',)}}}
class TimeInfo(MixinInfo):
"""
Container for meta information like name, description, format. This is
required when the object is used as a mixin column within a table, but can
be used as a general way to store meta information.
"""
attrs_from_parent = set(['unit']) # unit is read-only and None
attr_names = MixinInfo.attr_names | {'serialize_method'}
_supports_indexing = True
# The usual tuple of attributes needed for serialization is replaced
# by a property, since Time can be serialized different ways.
_represent_as_dict_extra_attrs = ('format', 'scale', 'precision',
'in_subfmt', 'out_subfmt', 'location',
'_delta_ut1_utc', '_delta_tdb_tt')
mask_val = np.ma.masked
@property
def _represent_as_dict_attrs(self):
method = self.serialize_method[self._serialize_context]
if method == 'formatted_value':
out = ('value',)
elif method == 'jd1_jd2':
out = ('jd1', 'jd2')
else:
raise ValueError("serialize method must be 'formatted_value' or 'jd1_jd2'")
return out + self._represent_as_dict_extra_attrs
def __init__(self, bound=False):
super().__init__(bound)
# If bound to a data object instance then create the dict of attributes
# which stores the info attribute values.
if bound:
# Specify how to serialize this object depending on context.
# If ``True`` for a context, then use formatted ``value`` attribute
# (e.g. the ISO time string). If ``False`` then use float jd1 and jd2.
self.serialize_method = {'fits': 'jd1_jd2',
'ecsv': 'formatted_value',
'hdf5': 'jd1_jd2',
'yaml': 'jd1_jd2',
None: 'jd1_jd2'}
@property
def unit(self):
return None
info_summary_stats = staticmethod(
data_info_factory(names=MixinInfo._stats,
funcs=[getattr(np, stat) for stat in MixinInfo._stats]))
# When Time has mean, std, min, max methods:
# funcs = [lambda x: getattr(x, stat)() for stat_name in MixinInfo._stats])
def _construct_from_dict_base(self, map):
if 'jd1' in map and 'jd2' in map:
format = map.pop('format')
map['format'] = 'jd'
map['val'] = map.pop('jd1')
map['val2'] = map.pop('jd2')
else:
format = map['format']
map['val'] = map.pop('value')
out = self._parent_cls(**map)
out.format = format
return out
def _construct_from_dict(self, map):
delta_ut1_utc = map.pop('_delta_ut1_utc', None)
delta_tdb_tt = map.pop('_delta_tdb_tt', None)
out = self._construct_from_dict_base(map)
if delta_ut1_utc is not None:
out._delta_ut1_utc = delta_ut1_utc
if delta_tdb_tt is not None:
out._delta_tdb_tt = delta_tdb_tt
return out
class TimeDeltaInfo(TimeInfo):
_represent_as_dict_extra_attrs = ('format', 'scale')
def _construct_from_dict(self, map):
return self._construct_from_dict_base(map)
class Time(ShapedLikeNDArray):
"""
Represent and manipulate times and dates for astronomy.
A `Time` object is initialized with one or more times in the ``val``
argument. The input times in ``val`` must conform to the specified
``format`` and must correspond to the specified time ``scale``. The
optional ``val2`` time input should be supplied only for numeric input
formats (e.g. JD) where very high precision (better than 64-bit precision)
is required.
The allowed values for ``format`` can be listed with::
>>> list(Time.FORMATS)
['jd', 'mjd', 'decimalyear', 'unix', 'cxcsec', 'gps', 'plot_date',
'datetime', 'iso', 'isot', 'yday', 'fits', 'byear', 'jyear', 'byear_str',
'jyear_str']
Parameters
----------
val : sequence, ndarray, number, str, bytes, or `~astropy.time.Time` object
Value(s) to initialize the time or times. Bytes are decoded as ascii.
val2 : sequence, ndarray, or number; optional
Value(s) to initialize the time or times. Only used for numerical
input, to help preserve precision.
format : str, optional
Format of input value(s)
scale : str, optional
Time scale of input value(s), must be one of the following:
('tai', 'tcb', 'tcg', 'tdb', 'tt', 'ut1', 'utc')
precision : int, optional
Digits of precision in string representation of time
in_subfmt : str, optional
Subformat for inputting string times
out_subfmt : str, optional
Subformat for outputting string times
location : `~astropy.coordinates.EarthLocation` or tuple, optional
If given as an tuple, it should be able to initialize an
an EarthLocation instance, i.e., either contain 3 items with units of
length for geocentric coordinates, or contain a longitude, latitude,
and an optional height for geodetic coordinates.
Can be a single location, or one for each input time.
copy : bool, optional
Make a copy of the input values
"""
SCALES = TIME_SCALES
"""List of time scales"""
FORMATS = TIME_FORMATS
"""Dict of time formats"""
# Make sure that reverse arithmetic (e.g., TimeDelta.__rmul__)
# gets called over the __mul__ of Numpy arrays.
__array_priority__ = 20000
# Declare that Time can be used as a Table column by defining the
# attribute where column attributes will be stored.
_astropy_column_attrs = None
def __new__(cls, val, val2=None, format=None, scale=None,
precision=None, in_subfmt=None, out_subfmt=None,
location=None, copy=False):
if isinstance(val, cls):
self = val.replicate(format=format, copy=copy)
else:
self = super().__new__(cls)
return self
def __getnewargs__(self):
return (self._time,)
def __init__(self, val, val2=None, format=None, scale=None,
precision=None, in_subfmt=None, out_subfmt=None,
location=None, copy=False):
if location is not None:
from ..coordinates import EarthLocation
if isinstance(location, EarthLocation):
self.location = location
else:
self.location = EarthLocation(*location)
else:
self.location = None
if isinstance(val, Time):
# Update _time formatting parameters if explicitly specified
if precision is not None:
self._time.precision = precision
if in_subfmt is not None:
self._time.in_subfmt = in_subfmt
if out_subfmt is not None:
self._time.out_subfmt = out_subfmt
if scale is not None:
self._set_scale(scale)
else:
self._init_from_vals(val, val2, format, scale, copy,
precision, in_subfmt, out_subfmt)
if self.location is not None and (self.location.size > 1 and
self.location.shape != self.shape):
try:
# check the location can be broadcast to self's shape.
self.location = np.broadcast_to(self.location, self.shape,
subok=True)
except Exception:
raise ValueError('The location with shape {0} cannot be '
'broadcast against time with shape {1}. '
'Typically, either give a single location or '
'one for each time.'
.format(self.location.shape, self.shape))
def _init_from_vals(self, val, val2, format, scale, copy,
precision=None, in_subfmt=None, out_subfmt=None):
"""
Set the internal _format, scale, and _time attrs from user
inputs. This handles coercion into the correct shapes and
some basic input validation.
"""
if precision is None:
precision = 3
if in_subfmt is None:
in_subfmt = '*'
if out_subfmt is None:
out_subfmt = '*'
# Coerce val into an array
val = _make_array(val, copy)
# If val2 is not None, ensure consistency
if val2 is not None:
val2 = _make_array(val2, copy)
try:
np.broadcast(val, val2)
except ValueError:
raise ValueError('Input val and val2 have inconsistent shape; '
'they cannot be broadcast together.')
if scale is not None:
if not (isinstance(scale, str) and
scale.lower() in self.SCALES):
raise ScaleValueError("Scale {0!r} is not in the allowed scales "
"{1}".format(scale,
sorted(self.SCALES)))
# If either of the input val, val2 are masked arrays then
# find the masked elements and fill them.
mask, val, val2 = _check_for_masked_and_fill(val, val2)
# Parse / convert input values into internal jd1, jd2 based on format
self._time = self._get_time_fmt(val, val2, format, scale,
precision, in_subfmt, out_subfmt)
self._format = self._time.name
# If any inputs were masked then masked jd2 accordingly. From above
# routine ``mask`` must be either Python bool False or an bool ndarray
# with shape broadcastable to jd2.
if mask is not False:
mask = np.broadcast_to(mask, self._time.jd2.shape)
self._time.jd2[mask] = np.nan
def _get_time_fmt(self, val, val2, format, scale,
precision, in_subfmt, out_subfmt):
"""
Given the supplied val, val2, format and scale try to instantiate
the corresponding TimeFormat class to convert the input values into
the internal jd1 and jd2.
If format is `None` and the input is a string-type or object array then
guess available formats and stop when one matches.
"""
if format is None and val.dtype.kind in ('S', 'U', 'O'):
formats = [(name, cls) for name, cls in self.FORMATS.items()
if issubclass(cls, TimeUnique)]
err_msg = ('any of the formats where the format keyword is '
'optional {0}'.format([name for name, cls in formats]))
# AstropyTime is a pseudo-format that isn't in the TIME_FORMATS registry,
# but try to guess it at the end.
formats.append(('astropy_time', TimeAstropyTime))
elif not (isinstance(format, str) and
format.lower() in self.FORMATS):
if format is None:
raise ValueError("No time format was given, and the input is "
"not unique")
else:
raise ValueError("Format {0!r} is not one of the allowed "
"formats {1}".format(format,
sorted(self.FORMATS)))
else:
formats = [(format, self.FORMATS[format])]
err_msg = 'the format class {0}'.format(format)
for format, FormatClass in formats:
try:
return FormatClass(val, val2, scale, precision, in_subfmt, out_subfmt)
except UnitConversionError:
raise
except (ValueError, TypeError):
pass
else:
raise ValueError('Input values did not match {0}'.format(err_msg))
@classmethod
def now(cls):
"""
Creates a new object corresponding to the instant in time this
method is called.
.. note::
"Now" is determined using the `~datetime.datetime.utcnow`
function, so its accuracy and precision is determined by that
function. Generally that means it is set by the accuracy of
your system clock.
Returns
-------
nowtime
A new `Time` object (or a subclass of `Time` if this is called from
such a subclass) at the current time.
"""
# call `utcnow` immediately to be sure it's ASAP
dtnow = datetime.utcnow()
return cls(val=dtnow, format='datetime', scale='utc')
info = TimeInfo()
@property
def writeable(self):
return self._time.jd1.flags.writeable & self._time.jd2.flags.writeable
@writeable.setter
def writeable(self, value):
self._time.jd1.flags.writeable = value
self._time.jd2.flags.writeable = value
@property
def format(self):
"""
Get or set time format.
The format defines the way times are represented when accessed via the
``.value`` attribute. By default it is the same as the format used for
initializing the `Time` instance, but it can be set to any other value
that could be used for initialization. These can be listed with::
>>> list(Time.FORMATS)
['jd', 'mjd', 'decimalyear', 'unix', 'cxcsec', 'gps', 'plot_date',
'datetime', 'iso', 'isot', 'yday', 'fits', 'byear', 'jyear', 'byear_str',
'jyear_str']
"""
return self._format
@format.setter
def format(self, format):
"""Set time format"""
if format not in self.FORMATS:
raise ValueError('format must be one of {0}'
.format(list(self.FORMATS)))
format_cls = self.FORMATS[format]
# If current output subformat is not in the new format then replace
# with default '*'
if hasattr(format_cls, 'subfmts'):
subfmt_names = [subfmt[0] for subfmt in format_cls.subfmts]
if self.out_subfmt not in subfmt_names:
self.out_subfmt = '*'
self._time = format_cls(self._time.jd1, self._time.jd2,
self._time._scale, self.precision,
in_subfmt=self.in_subfmt,
out_subfmt=self.out_subfmt,
from_jd=True)
self._format = format
def __repr__(self):
return ("<{0} object: scale='{1}' format='{2}' value={3}>"
.format(self.__class__.__name__, self.scale, self.format,
getattr(self, self.format)))
def __str__(self):
return str(getattr(self, self.format))
@property
def scale(self):
"""Time scale"""
return self._time.scale
def _set_scale(self, scale):
"""
This is the key routine that actually does time scale conversions.
This is not public and not connected to the read-only scale property.
"""
if scale == self.scale:
return
if scale not in self.SCALES:
raise ValueError("Scale {0!r} is not in the allowed scales {1}"
.format(scale, sorted(self.SCALES)))
# Determine the chain of scale transformations to get from the current
# scale to the new scale. MULTI_HOPS contains a dict of all
# transformations (xforms) that require intermediate xforms.
# The MULTI_HOPS dict is keyed by (sys1, sys2) in alphabetical order.
xform = (self.scale, scale)
xform_sort = tuple(sorted(xform))
multi = MULTI_HOPS.get(xform_sort, ())
xforms = xform_sort[:1] + multi + xform_sort[-1:]
# If we made the reverse xform then reverse it now.
if xform_sort != xform:
xforms = tuple(reversed(xforms))
# Transform the jd1,2 pairs through the chain of scale xforms.
jd1, jd2 = self._time.jd1, self._time.jd2_filled
for sys1, sys2 in zip(xforms[:-1], xforms[1:]):
# Some xforms require an additional delta_ argument that is
# provided through Time methods. These values may be supplied by
# the user or computed based on available approximations. The
# get_delta_ methods are available for only one combination of
# sys1, sys2 though the property applies for both xform directions.
args = [jd1, jd2]
for sys12 in ((sys1, sys2), (sys2, sys1)):
dt_method = '_get_delta_{0}_{1}'.format(*sys12)
try:
get_dt = getattr(self, dt_method)
except AttributeError:
pass
else:
args.append(get_dt(jd1, jd2))
break
conv_func = getattr(erfa, sys1 + sys2)
jd1, jd2 = conv_func(*args)
if self.masked:
jd2[self.mask] = np.nan
self._time = self.FORMATS[self.format](jd1, jd2, scale, self.precision,
self.in_subfmt, self.out_subfmt,
from_jd=True)
@property
def precision(self):
"""
Decimal precision when outputting seconds as floating point (int
value between 0 and 9 inclusive).
"""
return self._time.precision
@precision.setter
def precision(self, val):
del self.cache
if not isinstance(val, int) or val < 0 or val > 9:
raise ValueError('precision attribute must be an int between '
'0 and 9')
self._time.precision = val
@property
def in_subfmt(self):
"""
Unix wildcard pattern to select subformats for parsing string input
times.
"""
return self._time.in_subfmt
@in_subfmt.setter
def in_subfmt(self, val):
del self.cache
if not isinstance(val, str):
raise ValueError('in_subfmt attribute must be a string')
self._time.in_subfmt = val
@property
def out_subfmt(self):
"""
Unix wildcard pattern to select subformats for outputting times.
"""
return self._time.out_subfmt
@out_subfmt.setter
def out_subfmt(self, val):
del self.cache
if not isinstance(val, str):
raise ValueError('out_subfmt attribute must be a string')
self._time.out_subfmt = val
@property
def shape(self):
"""The shape of the time instances.
Like `~numpy.ndarray.shape`, can be set to a new shape by assigning a
tuple. Note that if different instances share some but not all
underlying data, setting the shape of one instance can make the other
instance unusable. Hence, it is strongly recommended to get new,
reshaped instances with the ``reshape`` method.
Raises
------
AttributeError
If the shape of the ``jd1``, ``jd2``, ``location``,
``delta_ut1_utc``, or ``delta_tdb_tt`` attributes cannot be changed
without the arrays being copied. For these cases, use the
`Time.reshape` method (which copies any arrays that cannot be
reshaped in-place).
"""
return self._time.jd1.shape
@shape.setter
def shape(self, shape):
del self.cache
# We have to keep track of arrays that were already reshaped,
# since we may have to return those to their original shape if a later
# shape-setting fails.
reshaped = []
oldshape = self.shape
# In-place reshape of data/attributes. Need to access _time.jd1/2 not
# self.jd1/2 because the latter are not guaranteed to be the actual
# data, and in fact should not be directly changeable from the public
# API.
for obj, attr in ((self._time, 'jd1'),
(self._time, 'jd2'),
(self, '_delta_ut1_utc'),
(self, '_delta_tdb_tt'),
(self, 'location')):
val = getattr(obj, attr, None)
if val is not None and val.size > 1:
try:
val.shape = shape
except AttributeError:
for val2 in reshaped:
val2.shape = oldshape
raise
else:
reshaped.append(val)
def _shaped_like_input(self, value):
out = value
if not self._time.jd1.shape and not np.ma.is_masked(value):
out = value.item()
return out
@property
def jd1(self):
"""
First of the two doubles that internally store time value(s) in JD.
"""
jd1 = self._time.mask_if_needed(self._time.jd1)
return self._shaped_like_input(jd1)
@property
def jd2(self):
"""
Second of the two doubles that internally store time value(s) in JD.
"""
jd2 = self._time.mask_if_needed(self._time.jd2)
return self._shaped_like_input(jd2)
@property
def value(self):
"""Time value(s) in current format"""
# The underlying way to get the time values for the current format is:
# self._shaped_like_input(self._time.to_value(parent=self))
# This is done in __getattr__. By calling getattr(self, self.format)
# the ``value`` attribute is cached.
return getattr(self, self.format)
@property
def masked(self):
return self._time.masked
@property
def mask(self):
return self._time.mask
def _make_value_equivalent(self, item, value):
"""Coerce setitem value into an equivalent Time object"""
# If there is a vector location then broadcast to the Time shape
# and then select with ``item``
if self.location is not None and self.location.shape:
self_location = np.broadcast_to(self.location, self.shape, subok=True)[item]
else:
self_location = self.location
if isinstance(value, Time):
# Make sure locations are compatible. Location can be either None or
# a Location object.
if self_location is None and value.location is None:
match = True
elif ((self_location is None and value.location is not None) or
(self_location is not None and value.location is None)):
match = False
else:
match = np.all(self_location == value.location)
if not match:
raise ValueError('cannot set to Time with different location: '
'expected location={} and '
'got location={}'
.format(self_location, value.location))
else:
try:
value = self.__class__(value, scale=self.scale, location=self_location)
except Exception:
try:
value = self.__class__(value, scale=self.scale, format=self.format,
location=self_location)
except Exception as err:
raise ValueError('cannot convert value to a compatible Time object: {}'
.format(err))
return value
def __setitem__(self, item, value):
if not self.writeable:
if self.shape:
raise ValueError('{} object is read-only. Make a '
'copy() or set "writeable" attribute to True.'
.format(self.__class__.__name__))
else:
raise ValueError('scalar {} object is read-only.'
.format(self.__class__.__name__))
# Any use of setitem results in immediate cache invalidation
del self.cache
# Setting invalidates transform deltas
for attr in ('_delta_tdb_tt', '_delta_ut1_utc'):
if hasattr(self, attr):
delattr(self, attr)
if value in (np.ma.masked, np.nan):
self._time.jd2[item] = np.nan
return
value = self._make_value_equivalent(item, value)
# Finally directly set the jd1/2 values. Locations are known to match.
if self.scale is not None:
value = getattr(value, self.scale)
self._time.jd1[item] = value._time.jd1
self._time.jd2[item] = value._time.jd2
def light_travel_time(self, skycoord, kind='barycentric', location=None, ephemeris=None):
"""Light travel time correction to the barycentre or heliocentre.
The frame transformations used to calculate the location of the solar
system barycentre and the heliocentre rely on the erfa routine epv00,
which is consistent with the JPL DE405 ephemeris to an accuracy of
11.2 km, corresponding to a light travel time of 4 microseconds.
The routine assumes the source(s) are at large distance, i.e., neglects
finite-distance effects.
Parameters
----------
skycoord : `~astropy.coordinates.SkyCoord`
The sky location to calculate the correction for.
kind : str, optional
``'barycentric'`` (default) or ``'heliocentric'``
location : `~astropy.coordinates.EarthLocation`, optional
The location of the observatory to calculate the correction for.
If no location is given, the ``location`` attribute of the Time
object is used
ephemeris : str, optional
Solar system ephemeris to use (e.g., 'builtin', 'jpl'). By default,
use the one set with ``astropy.coordinates.solar_system_ephemeris.set``.
For more information, see `~astropy.coordinates.solar_system_ephemeris`.
Returns
-------
time_offset : `~astropy.time.TimeDelta`
The time offset between the barycentre or Heliocentre and Earth,
in TDB seconds. Should be added to the original time to get the
time in the Solar system barycentre or the Heliocentre.
"""
if kind.lower() not in ('barycentric', 'heliocentric'):
raise ValueError("'kind' parameter must be one of 'heliocentric' "
"or 'barycentric'")
if location is None:
if self.location is None:
raise ValueError('An EarthLocation needs to be set or passed '
'in to calculate bary- or heliocentric '
'corrections')
location = self.location
from ..coordinates import (UnitSphericalRepresentation, CartesianRepresentation,
HCRS, ICRS, GCRS, solar_system_ephemeris)
# ensure sky location is ICRS compatible
if not skycoord.is_transformable_to(ICRS()):
raise ValueError("Given skycoord is not transformable to the ICRS")
# get location of observatory in ITRS coordinates at this Time
try:
itrs = location.get_itrs(obstime=self)
except Exception:
raise ValueError("Supplied location does not have a valid `get_itrs` method")
with solar_system_ephemeris.set(ephemeris):
if kind.lower() == 'heliocentric':
# convert to heliocentric coordinates, aligned with ICRS
cpos = itrs.transform_to(HCRS(obstime=self)).cartesian.xyz
else:
# first we need to convert to GCRS coordinates with the correct
# obstime, since ICRS coordinates have no frame time
gcrs_coo = itrs.transform_to(GCRS(obstime=self))
# convert to barycentric (BCRS) coordinates, aligned with ICRS
cpos = gcrs_coo.transform_to(ICRS()).cartesian.xyz
# get unit ICRS vector to star
spos = (skycoord.icrs.represent_as(UnitSphericalRepresentation).
represent_as(CartesianRepresentation).xyz)
# Move X,Y,Z to last dimension, to enable possible broadcasting below.
cpos = np.rollaxis(cpos, 0, cpos.ndim)
spos = np.rollaxis(spos, 0, spos.ndim)
# calculate light travel time correction
tcor_val = (spos * cpos).sum(axis=-1) / const.c
return TimeDelta(tcor_val, scale='tdb')
def sidereal_time(self, kind, longitude=None, model=None):
"""Calculate sidereal time.
Parameters
---------------
kind : str
``'mean'`` or ``'apparent'``, i.e., accounting for precession
only, or also for nutation.
longitude : `~astropy.units.Quantity`, `str`, or `None`; optional
The longitude on the Earth at which to compute the sidereal time.
Can be given as a `~astropy.units.Quantity` with angular units
(or an `~astropy.coordinates.Angle` or
`~astropy.coordinates.Longitude`), or as a name of an
observatory (currently, only ``'greenwich'`` is supported,
equivalent to 0 deg). If `None` (default), the ``lon`` attribute of
the Time object is used.
model : str or `None`; optional
Precession (and nutation) model to use. The available ones are:
- {0}: {1}
- {2}: {3}
If `None` (default), the last (most recent) one from the appropriate
list above is used.
Returns
-------
sidereal time : `~astropy.coordinates.Longitude`
Sidereal time as a quantity with units of hourangle
""" # docstring is formatted below
from ..coordinates import Longitude
if kind.lower() not in SIDEREAL_TIME_MODELS.keys():
raise ValueError('The kind of sidereal time has to be {0}'.format(
' or '.join(sorted(SIDEREAL_TIME_MODELS.keys()))))
available_models = SIDEREAL_TIME_MODELS[kind.lower()]
if model is None:
model = sorted(available_models.keys())[-1]
else:
if model.upper() not in available_models:
raise ValueError(
'Model {0} not implemented for {1} sidereal time; '
'available models are {2}'
.format(model, kind, sorted(available_models.keys())))
if longitude is None:
if self.location is None:
raise ValueError('No longitude is given but the location for '
'the Time object is not set.')
longitude = self.location.lon
elif longitude == 'greenwich':
longitude = Longitude(0., u.degree,
wrap_angle=180.*u.degree)
else:
# sanity check on input
longitude = Longitude(longitude, u.degree,
wrap_angle=180.*u.degree)
gst = self._erfa_sidereal_time(available_models[model.upper()])
return Longitude(gst + longitude, u.hourangle)
if isinstance(sidereal_time.__doc__, str):
sidereal_time.__doc__ = sidereal_time.__doc__.format(
'apparent', sorted(SIDEREAL_TIME_MODELS['apparent'].keys()),
'mean', sorted(SIDEREAL_TIME_MODELS['mean'].keys()))
def _erfa_sidereal_time(self, model):
"""Calculate a sidereal time using a IAU precession/nutation model."""
from ..coordinates import Longitude
erfa_function = model['function']
erfa_parameters = [getattr(getattr(self, scale)._time, jd_part)
for scale in model['scales']
for jd_part in ('jd1', 'jd2_filled')]
sidereal_time = erfa_function(*erfa_parameters)
if self.masked:
sidereal_time[self.mask] = np.nan
return Longitude(sidereal_time, u.radian).to(u.hourangle)
def copy(self, format=None):
"""
Return a fully independent copy the Time object, optionally changing
the format.
If ``format`` is supplied then the time format of the returned Time
object will be set accordingly, otherwise it will be unchanged from the
original.
In this method a full copy of the internal time arrays will be made.
The internal time arrays are normally not changeable by the user so in
most cases the ``replicate()`` method should be used.
Parameters
----------
format : str, optional
Time format of the copy.
Returns
-------
tm : Time object
Copy of this object
"""
return self._apply('copy', format=format)
def replicate(self, format=None, copy=False):
"""
Return a replica of the Time object, optionally changing the format.
If ``format`` is supplied then the time format of the returned Time
object will be set accordingly, otherwise it will be unchanged from the
original.
If ``copy`` is set to `True` then a full copy of the internal time arrays
will be made. By default the replica will use a reference to the
original arrays when possible to save memory. The internal time arrays
are normally not changeable by the user so in most cases it should not
be necessary to set ``copy`` to `True`.
The convenience method copy() is available in which ``copy`` is `True`
by default.
Parameters
----------
format : str, optional
Time format of the replica.
copy : bool, optional
Return a true copy instead of using references where possible.
Returns
-------
tm : Time object
Replica of this object
"""
return self._apply('copy' if copy else 'replicate', format=format)
def _apply(self, method, *args, format=None, **kwargs):
"""Create a new time object, possibly applying a method to the arrays.
Parameters
----------
method : str or callable
If string, can be 'replicate' or the name of a relevant
`~numpy.ndarray` method. In the former case, a new time instance
with unchanged internal data is created, while in the latter the
method is applied to the internal ``jd1`` and ``jd2`` arrays, as
well as to possible ``location``, ``_delta_ut1_utc``, and
``_delta_tdb_tt`` arrays.
If a callable, it is directly applied to the above arrays.
Examples: 'copy', '__getitem__', 'reshape', `~numpy.broadcast_to`.
args : tuple
Any positional arguments for ``method``.
kwargs : dict
Any keyword arguments for ``method``. If the ``format`` keyword
argument is present, this will be used as the Time format of the
replica.
Examples
--------
Some ways this is used internally::
copy : ``_apply('copy')``
replicate : ``_apply('replicate')``
reshape : ``_apply('reshape', new_shape)``
index or slice : ``_apply('__getitem__', item)``
broadcast : ``_apply(np.broadcast, shape=new_shape)``
"""
new_format = self.format if format is None else format
if callable(method):
apply_method = lambda array: method(array, *args, **kwargs)
else:
if method == 'replicate':
apply_method = None
else:
apply_method = operator.methodcaller(method, *args, **kwargs)
jd1, jd2 = self._time.jd1, self._time.jd2
if apply_method:
jd1 = apply_method(jd1)
jd2 = apply_method(jd2)
# Get a new instance of our class and set its attributes directly.
tm = super().__new__(self.__class__)
tm._time = TimeJD(jd1, jd2, self.scale, self.precision,
self.in_subfmt, self.out_subfmt, from_jd=True)
# Optional ndarray attributes.
for attr in ('_delta_ut1_utc', '_delta_tdb_tt', 'location',
'precision', 'in_subfmt', 'out_subfmt'):
try:
val = getattr(self, attr)
except AttributeError:
continue
if apply_method:
# Apply the method to any value arrays (though skip if there is
# only a single element and the method would return a view,
# since in that case nothing would change).
if getattr(val, 'size', 1) > 1:
val = apply_method(val)
elif method == 'copy' or method == 'flatten':
# flatten should copy also for a single element array, but
# we cannot use it directly for array scalars, since it
# always returns a one-dimensional array. So, just copy.
val = copy.copy(val)
setattr(tm, attr, val)
# Copy other 'info' attr only if it has actually been defined.
# See PR #3898 for further explanation and justification, along
# with Quantity.__array_finalize__
if 'info' in self.__dict__:
tm.info = self.info
# Make the new internal _time object corresponding to the format
# in the copy. If the format is unchanged this process is lightweight
# and does not create any new arrays.
if new_format not in tm.FORMATS:
raise ValueError('format must be one of {0}'
.format(list(tm.FORMATS)))
NewFormat = tm.FORMATS[new_format]
tm._time = NewFormat(tm._time.jd1, tm._time.jd2,
tm._time._scale, tm.precision,
tm.in_subfmt, tm.out_subfmt,
from_jd=True)
tm._format = new_format
return tm
def __copy__(self):
"""
Overrides the default behavior of the `copy.copy` function in
the python stdlib to behave like `Time.copy`. Does *not* make a
copy of the JD arrays - only copies by reference.
"""
return self.replicate()
def __deepcopy__(self, memo):
"""
Overrides the default behavior of the `copy.deepcopy` function
in the python stdlib to behave like `Time.copy`. Does make a
copy of the JD arrays.
"""
return self.copy()
def _advanced_index(self, indices, axis=None, keepdims=False):
"""Turn argmin, argmax output into an advanced index.
Argmin, argmax output contains indices along a given axis in an array
shaped like the other dimensions. To use this to get values at the
correct location, a list is constructed in which the other axes are
indexed sequentially. For ``keepdims`` is ``True``, the net result is
the same as constructing an index grid with ``np.ogrid`` and then
replacing the ``axis`` item with ``indices`` with its shaped expanded
at ``axis``. For ``keepdims`` is ``False``, the result is the same but
with the ``axis`` dimension removed from all list entries.
For ``axis`` is ``None``, this calls :func:`~numpy.unravel_index`.
Parameters
----------
indices : array
Output of argmin or argmax.
axis : int or None
axis along which argmin or argmax was used.
keepdims : bool
Whether to construct indices that keep or remove the axis along
which argmin or argmax was used. Default: ``False``.
Returns
-------
advanced_index : list of arrays
Suitable for use as an advanced index.
"""
if axis is None:
return np.unravel_index(indices, self.shape)
ndim = self.ndim
if axis < 0:
axis = axis + ndim
if keepdims and indices.ndim < self.ndim:
indices = np.expand_dims(indices, axis)
return [(indices if i == axis else np.arange(s).reshape(
(1,)*(i if keepdims or i < axis else i-1) + (s,) +
(1,)*(ndim-i-(1 if keepdims or i > axis else 2))))
for i, s in enumerate(self.shape)]
def argmin(self, axis=None, out=None):
"""Return indices of the minimum values along the given axis.
This is similar to :meth:`~numpy.ndarray.argmin`, but adapted to ensure
that the full precision given by the two doubles ``jd1`` and ``jd2``
is used. See :func:`~numpy.argmin` for detailed documentation.
"""
# first get the minimum at normal precision.
jd = self.jd1 + self.jd2
if NUMPY_LT_1_11_2:
# MaskedArray.min ignores keepdims so do it by hand
approx = np.min(jd, axis)
if axis is not None:
approx = np.expand_dims(approx, axis)
else:
approx = np.min(jd, axis, keepdims=True)
# Approx is very close to the true minimum, and by subtracting it at
# full precision, all numbers near 0 can be represented correctly,
# so we can be sure we get the true minimum.
# The below is effectively what would be done for
# dt = (self - self.__class__(approx, format='jd')).jd
# which translates to:
# approx_jd1, approx_jd2 = day_frac(approx, 0.)
# dt = (self.jd1 - approx_jd1) + (self.jd2 - approx_jd2)
dt = (self.jd1 - approx) + self.jd2
return dt.argmin(axis, out)
def argmax(self, axis=None, out=None):
"""Return indices of the maximum values along the given axis.
This is similar to :meth:`~numpy.ndarray.argmax`, but adapted to ensure
that the full precision given by the two doubles ``jd1`` and ``jd2``
is used. See :func:`~numpy.argmax` for detailed documentation.
"""
# For procedure, see comment on argmin.
jd = self.jd1 + self.jd2
if NUMPY_LT_1_11_2:
# MaskedArray.max ignores keepdims so do it by hand (numpy <= 1.10)
approx = np.max(jd, axis)
if axis is not None:
approx = np.expand_dims(approx, axis)
else:
approx = np.max(jd, axis, keepdims=True)
dt = (self.jd1 - approx) + self.jd2
return dt.argmax(axis, out)
def argsort(self, axis=-1):
"""Returns the indices that would sort the time array.
This is similar to :meth:`~numpy.ndarray.argsort`, but adapted to ensure
that the full precision given by the two doubles ``jd1`` and ``jd2``
is used, and that corresponding attributes are copied. Internally,
it uses :func:`~numpy.lexsort`, and hence no sort method can be chosen.
"""
jd_approx = self.jd
jd_remainder = (self - self.__class__(jd_approx, format='jd')).jd
if axis is None:
return np.lexsort((jd_remainder.ravel(), jd_approx.ravel()))
else:
return np.lexsort(keys=(jd_remainder, jd_approx), axis=axis)
def min(self, axis=None, out=None, keepdims=False):
"""Minimum along a given axis.
This is similar to :meth:`~numpy.ndarray.min`, but adapted to ensure
that the full precision given by the two doubles ``jd1`` and ``jd2``
is used, and that corresponding attributes are copied.
Note that the ``out`` argument is present only for compatibility with
``np.min``; since `Time` instances are immutable, it is not possible
to have an actual ``out`` to store the result in.
"""
if out is not None:
raise ValueError("Since `Time` instances are immutable, ``out`` "
"cannot be set to anything but ``None``.")
return self[self._advanced_index(self.argmin(axis), axis, keepdims)]
def max(self, axis=None, out=None, keepdims=False):
"""Maximum along a given axis.
This is similar to :meth:`~numpy.ndarray.max`, but adapted to ensure
that the full precision given by the two doubles ``jd1`` and ``jd2``
is used, and that corresponding attributes are copied.
Note that the ``out`` argument is present only for compatibility with
``np.max``; since `Time` instances are immutable, it is not possible
to have an actual ``out`` to store the result in.
"""
if out is not None:
raise ValueError("Since `Time` instances are immutable, ``out`` "
"cannot be set to anything but ``None``.")
return self[self._advanced_index(self.argmax(axis), axis, keepdims)]
def ptp(self, axis=None, out=None, keepdims=False):
"""Peak to peak (maximum - minimum) along a given axis.
This is similar to :meth:`~numpy.ndarray.ptp`, but adapted to ensure
that the full precision given by the two doubles ``jd1`` and ``jd2``
is used.
Note that the ``out`` argument is present only for compatibility with
`~numpy.ptp`; since `Time` instances are immutable, it is not possible
to have an actual ``out`` to store the result in.
"""
if out is not None:
raise ValueError("Since `Time` instances are immutable, ``out`` "
"cannot be set to anything but ``None``.")
return (self.max(axis, keepdims=keepdims) -
self.min(axis, keepdims=keepdims))
def sort(self, axis=-1):
"""Return a copy sorted along the specified axis.
This is similar to :meth:`~numpy.ndarray.sort`, but internally uses
indexing with :func:`~numpy.lexsort` to ensure that the full precision
given by the two doubles ``jd1`` and ``jd2`` is kept, and that
corresponding attributes are properly sorted and copied as well.
Parameters
----------
axis : int or None
Axis to be sorted. If ``None``, the flattened array is sorted.
By default, sort over the last axis.
"""
return self[self._advanced_index(self.argsort(axis), axis,
keepdims=True)]
@property
def cache(self):
"""
Return the cache associated with this instance.
"""
return self._time.cache
@cache.deleter
def cache(self):
del self._time.cache
def __getattr__(self, attr):
"""
Get dynamic attributes to output format or do timescale conversion.
"""
if attr in self.SCALES and self.scale is not None:
cache = self.cache['scale']
if attr not in cache:
if attr == self.scale:
tm = self
else:
tm = self.replicate()
tm._set_scale(attr)
if tm.shape:
# Prevent future modification of cached array-like object
tm.writeable = False
cache[attr] = tm
return cache[attr]
elif attr in self.FORMATS:
cache = self.cache['format']
if attr not in cache:
if attr == self.format:
tm = self
else:
tm = self.replicate(format=attr)
value = tm._shaped_like_input(tm._time.to_value(parent=tm))
cache[attr] = value
return cache[attr]
elif attr in TIME_SCALES: # allowed ones done above (self.SCALES)
if self.scale is None:
raise ScaleValueError("Cannot convert TimeDelta with "
"undefined scale to any defined scale.")
else:
raise ScaleValueError("Cannot convert {0} with scale "
"'{1}' to scale '{2}'"
.format(self.__class__.__name__,
self.scale, attr))
else:
# Should raise AttributeError
return self.__getattribute__(attr)
@override__dir__
def __dir__(self):
result = set(self.SCALES)
result.update(self.FORMATS)
return result
def _match_shape(self, val):
"""
Ensure that `val` is matched to length of self. If val has length 1
then broadcast, otherwise cast to double and make sure shape matches.
"""
val = _make_array(val, copy=True) # be conservative and copy
if val.size > 1 and val.shape != self.shape:
try:
# check the value can be broadcast to the shape of self.
val = np.broadcast_to(val, self.shape, subok=True)
except Exception:
raise ValueError('Attribute shape must match or be '
'broadcastable to that of Time object. '
'Typically, give either a single value or '
'one for each time.')
return val
def get_delta_ut1_utc(self, iers_table=None, return_status=False):
"""Find UT1 - UTC differences by interpolating in IERS Table.
Parameters
----------
iers_table : ``astropy.utils.iers.IERS`` table, optional
Table containing UT1-UTC differences from IERS Bulletins A
and/or B. If `None`, use default version (see
``astropy.utils.iers``)
return_status : bool
Whether to return status values. If `False` (default), iers
raises `IndexError` if any time is out of the range
covered by the IERS table.
Returns
-------
ut1_utc : float or float array
UT1-UTC, interpolated in IERS Table
status : int or int array
Status values (if ``return_status=`True```)::
``astropy.utils.iers.FROM_IERS_B``
``astropy.utils.iers.FROM_IERS_A``
``astropy.utils.iers.FROM_IERS_A_PREDICTION``
``astropy.utils.iers.TIME_BEFORE_IERS_RANGE``
``astropy.utils.iers.TIME_BEYOND_IERS_RANGE``
Notes
-----
In normal usage, UT1-UTC differences are calculated automatically
on the first instance ut1 is needed.
Examples
--------
To check in code whether any times are before the IERS table range::
>>> from astropy.utils.iers import TIME_BEFORE_IERS_RANGE
>>> t = Time(['1961-01-01', '2000-01-01'], scale='utc')
>>> delta, status = t.get_delta_ut1_utc(return_status=True)
>>> status == TIME_BEFORE_IERS_RANGE
array([ True, False]...)
"""
if iers_table is None:
from ..utils.iers import IERS
iers_table = IERS.open()
return iers_table.ut1_utc(self.utc, return_status=return_status)
# Property for ERFA DUT arg = UT1 - UTC
def _get_delta_ut1_utc(self, jd1=None, jd2=None):
"""
Get ERFA DUT arg = UT1 - UTC. This getter takes optional jd1 and
jd2 args because it gets called that way when converting time scales.
If delta_ut1_utc is not yet set, this will interpolate them from the
the IERS table.
"""
# Sec. 4.3.1: the arg DUT is the quantity delta_UT1 = UT1 - UTC in
# seconds. It is obtained from tables published by the IERS.
if not hasattr(self, '_delta_ut1_utc'):
from ..utils.iers import IERS_Auto
iers_table = IERS_Auto.open()
# jd1, jd2 are normally set (see above), except if delta_ut1_utc
# is access directly; ensure we behave as expected for that case
if jd1 is None:
self_utc = self.utc
jd1, jd2 = self_utc._time.jd1, self_utc._time.jd2_filled
scale = 'utc'
else:
scale = self.scale
# interpolate UT1-UTC in IERS table
delta = iers_table.ut1_utc(jd1, jd2)
# if we interpolated using UT1 jds, we may be off by one
# second near leap seconds (and very slightly off elsewhere)
if scale == 'ut1':
# calculate UTC using the offset we got; the ERFA routine
# is tolerant of leap seconds, so will do this right
jd1_utc, jd2_utc = erfa.ut1utc(jd1, jd2, delta)
# calculate a better estimate using the nearly correct UTC
delta = iers_table.ut1_utc(jd1_utc, jd2_utc)
self._set_delta_ut1_utc(delta)
return self._delta_ut1_utc
def _set_delta_ut1_utc(self, val):
del self.cache
if hasattr(val, 'to'): # Matches Quantity but also TimeDelta.
val = val.to(u.second).value
val = self._match_shape(val)
self._delta_ut1_utc = val
# Note can't use @property because _get_delta_tdb_tt is explicitly
# called with the optional jd1 and jd2 args.
delta_ut1_utc = property(_get_delta_ut1_utc, _set_delta_ut1_utc)
"""UT1 - UTC time scale offset"""
# Property for ERFA DTR arg = TDB - TT
def _get_delta_tdb_tt(self, jd1=None, jd2=None):
if not hasattr(self, '_delta_tdb_tt'):
# If jd1 and jd2 are not provided (which is the case for property
# attribute access) then require that the time scale is TT or TDB.
# Otherwise the computations here are not correct.
if jd1 is None or jd2 is None:
if self.scale not in ('tt', 'tdb'):
raise ValueError('Accessing the delta_tdb_tt attribute '
'is only possible for TT or TDB time '
'scales')
else:
jd1 = self._time.jd1
jd2 = self._time.jd2_filled
# First go from the current input time (which is either
# TDB or TT) to an approximate UT1. Since TT and TDB are
# pretty close (few msec?), assume TT. Similarly, since the
# UT1 terms are very small, use UTC instead of UT1.
njd1, njd2 = erfa.tttai(jd1, jd2)
njd1, njd2 = erfa.taiutc(njd1, njd2)
# subtract 0.5, so UT is fraction of the day from midnight
ut = day_frac(njd1 - 0.5, njd2)[1]
if self.location is None:
from ..coordinates import EarthLocation
location = EarthLocation.from_geodetic(0., 0., 0.)
else:
location = self.location
# Geodetic params needed for d_tdb_tt()
lon = location.lon
rxy = np.hypot(location.x, location.y)
z = location.z
self._delta_tdb_tt = erfa.dtdb(
jd1, jd2, ut, lon.to_value(u.radian),
rxy.to_value(u.km), z.to_value(u.km))
return self._delta_tdb_tt
def _set_delta_tdb_tt(self, val):
del self.cache
if hasattr(val, 'to'): # Matches Quantity but also TimeDelta.
val = val.to(u.second).value
val = self._match_shape(val)
self._delta_tdb_tt = val
# Note can't use @property because _get_delta_tdb_tt is explicitly
# called with the optional jd1 and jd2 args.
delta_tdb_tt = property(_get_delta_tdb_tt, _set_delta_tdb_tt)
"""TDB - TT time scale offset"""
def __sub__(self, other):
if not isinstance(other, Time):
try:
other = TimeDelta(other)
except Exception:
raise OperandTypeError(self, other, '-')
# Tdelta - something is dealt with in TimeDelta, so we have
# T - Tdelta = T
# T - T = Tdelta
other_is_delta = isinstance(other, TimeDelta)
# we need a constant scale to calculate, which is guaranteed for
# TimeDelta, but not for Time (which can be UTC)
if other_is_delta: # T - Tdelta
out = self.replicate()
if self.scale in other.SCALES:
if other.scale not in (out.scale, None):
other = getattr(other, out.scale)
else:
out._set_scale(other.scale if other.scale is not None
else 'tai')
# remove attributes that are invalidated by changing time
for attr in ('_delta_ut1_utc', '_delta_tdb_tt'):
if hasattr(out, attr):
delattr(out, attr)
else: # T - T
self_time = (self._time if self.scale in TIME_DELTA_SCALES
else self.tai._time)
# set up TimeDelta, subtraction to be done shortly
out = TimeDelta(self_time.jd1, self_time.jd2, format='jd',
scale=self_time.scale)
if other.scale != out.scale:
other = getattr(other, out.scale)
jd1 = out._time.jd1 - other._time.jd1
jd2 = out._time.jd2 - other._time.jd2
out._time.jd1, out._time.jd2 = day_frac(jd1, jd2)
if other_is_delta:
# Go back to left-side scale if needed
out._set_scale(self.scale)
return out
def __add__(self, other):
if not isinstance(other, Time):
try:
other = TimeDelta(other)
except Exception:
raise OperandTypeError(self, other, '+')
# Tdelta + something is dealt with in TimeDelta, so we have
# T + Tdelta = T
# T + T = error
if not isinstance(other, TimeDelta):
raise OperandTypeError(self, other, '+')
# ideally, we calculate in the scale of the Time item, since that is
# what we want the output in, but this may not be possible, since
# TimeDelta cannot be converted arbitrarily
out = self.replicate()
if self.scale in other.SCALES:
if other.scale not in (out.scale, None):
other = getattr(other, out.scale)
else:
out._set_scale(other.scale if other.scale is not None else 'tai')
# remove attributes that are invalidated by changing time
for attr in ('_delta_ut1_utc', '_delta_tdb_tt'):
if hasattr(out, attr):
delattr(out, attr)
jd1 = out._time.jd1 + other._time.jd1
jd2 = out._time.jd2 + other._time.jd2
out._time.jd1, out._time.jd2 = day_frac(jd1, jd2)
# Go back to left-side scale if needed
out._set_scale(self.scale)
return out
def __radd__(self, other):
return self.__add__(other)
def __rsub__(self, other):
out = self.__sub__(other)
return -out
def _time_difference(self, other, op=None):
"""If other is of same class as self, return difference in self.scale.
Otherwise, raise OperandTypeError.
"""
if other.__class__ is not self.__class__:
try:
other = self.__class__(other, scale=self.scale)
except Exception:
raise OperandTypeError(self, other, op)
if(self.scale is not None and self.scale not in other.SCALES or
other.scale is not None and other.scale not in self.SCALES):
raise TypeError("Cannot compare TimeDelta instances with scales "
"'{0}' and '{1}'".format(self.scale, other.scale))
if self.scale is not None and other.scale is not None:
other = getattr(other, self.scale)
return (self.jd1 - other.jd1) + (self.jd2 - other.jd2)
def __lt__(self, other):
return self._time_difference(other, '<') < 0.
def __le__(self, other):
return self._time_difference(other, '<=') <= 0.
def __eq__(self, other):
"""
If other is an incompatible object for comparison, return `False`.
Otherwise, return `True` if the time difference between self and
other is zero.
"""
try:
diff = self._time_difference(other)
except OperandTypeError:
return False
return diff == 0.
def __ne__(self, other):
"""
If other is an incompatible object for comparison, return `True`.
Otherwise, return `False` if the time difference between self and
other is zero.
"""
try:
diff = self._time_difference(other)
except OperandTypeError:
return True
return diff != 0.
def __gt__(self, other):
return self._time_difference(other, '>') > 0.
def __ge__(self, other):
return self._time_difference(other, '>=') >= 0.
def to_datetime(self, timezone=None):
tm = self.replicate(format='datetime')
return tm._shaped_like_input(tm._time.to_value(timezone))
to_datetime.__doc__ = TimeDatetime.to_value.__doc__
class TimeDelta(Time):
"""
Represent the time difference between two times.
A TimeDelta object is initialized with one or more times in the ``val``
argument. The input times in ``val`` must conform to the specified
``format``. The optional ``val2`` time input should be supplied only for
numeric input formats (e.g. JD) where very high precision (better than
64-bit precision) is required.
The allowed values for ``format`` can be listed with::
>>> list(TimeDelta.FORMATS)
['sec', 'jd']
Note that for time differences, the scale can be among three groups:
geocentric ('tai', 'tt', 'tcg'), barycentric ('tcb', 'tdb'), and rotational
('ut1'). Within each of these, the scales for time differences are the
same. Conversion between geocentric and barycentric is possible, as there
is only a scale factor change, but one cannot convert to or from 'ut1', as
this requires knowledge of the actual times, not just their difference. For
a similar reason, 'utc' is not a valid scale for a time difference: a UTC
day is not always 86400 seconds.
Parameters
----------
val : sequence, ndarray, number, or `~astropy.time.TimeDelta` object
Value(s) to initialize the time difference(s).
val2 : numpy ndarray, list, str, or number; optional
Additional values, as needed to preserve precision.
format : str, optional
Format of input value(s)
scale : str, optional
Time scale of input value(s), must be one of the following values:
('tdb', 'tt', 'ut1', 'tcg', 'tcb', 'tai'). If not given (or
``None``), the scale is arbitrary; when added or subtracted from a
``Time`` instance, it will be used without conversion.
copy : bool, optional
Make a copy of the input values
"""
SCALES = TIME_DELTA_SCALES
"""List of time delta scales."""
FORMATS = TIME_DELTA_FORMATS
"""Dict of time delta formats."""
info = TimeDeltaInfo()
def __init__(self, val, val2=None, format=None, scale=None, copy=False):
if isinstance(val, TimeDelta):
if scale is not None:
self._set_scale(scale)
else:
if format is None:
try:
val = val.to(u.day)
if val2 is not None:
val2 = val2.to(u.day)
except Exception:
raise ValueError('Only Quantities with Time units can '
'be used to initiate {0} instances .'
.format(self.__class__.__name__))
format = 'jd'
self._init_from_vals(val, val2, format, scale, copy)
if scale is not None:
self.SCALES = TIME_DELTA_TYPES[scale]
def replicate(self, *args, **kwargs):
out = super().replicate(*args, **kwargs)
out.SCALES = self.SCALES
return out
def _set_scale(self, scale):
"""
This is the key routine that actually does time scale conversions.
This is not public and not connected to the read-only scale property.
"""
if scale == self.scale:
return
if scale not in self.SCALES:
raise ValueError("Scale {0!r} is not in the allowed scales {1}"
.format(scale, sorted(self.SCALES)))
# For TimeDelta, there can only be a change in scale factor,
# which is written as time2 - time1 = scale_offset * time1
scale_offset = SCALE_OFFSETS[(self.scale, scale)]
if scale_offset is None:
self._time.scale = scale
else:
jd1, jd2 = self._time.jd1, self._time.jd2
offset1, offset2 = day_frac(jd1, jd2, factor=scale_offset)
self._time = self.FORMATS[self.format](
jd1 + offset1, jd2 + offset2, scale,
self.precision, self.in_subfmt,
self.out_subfmt, from_jd=True)
def __add__(self, other):
# only deal with TimeDelta + TimeDelta
if isinstance(other, Time):
if not isinstance(other, TimeDelta):
return other.__add__(self)
else:
try:
other = TimeDelta(other)
except Exception:
raise OperandTypeError(self, other, '+')
# the scales should be compatible (e.g., cannot convert TDB to TAI)
if(self.scale is not None and self.scale not in other.SCALES or
other.scale is not None and other.scale not in self.SCALES):
raise TypeError("Cannot add TimeDelta instances with scales "
"'{0}' and '{1}'".format(self.scale, other.scale))
# adjust the scale of other if the scale of self is set (or no scales)
if self.scale is not None or other.scale is None:
out = self.replicate()
if other.scale is not None:
other = getattr(other, self.scale)
else:
out = other.replicate()
jd1 = self._time.jd1 + other._time.jd1
jd2 = self._time.jd2 + other._time.jd2
out._time.jd1, out._time.jd2 = day_frac(jd1, jd2)
return out
def __sub__(self, other):
# only deal with TimeDelta - TimeDelta
if isinstance(other, Time):
if not isinstance(other, TimeDelta):
raise OperandTypeError(self, other, '-')
else:
try:
other = TimeDelta(other)
except Exception:
raise OperandTypeError(self, other, '-')
# the scales should be compatible (e.g., cannot convert TDB to TAI)
if(self.scale is not None and self.scale not in other.SCALES or
other.scale is not None and other.scale not in self.SCALES):
raise TypeError("Cannot subtract TimeDelta instances with scales "
"'{0}' and '{1}'".format(self.scale, other.scale))
# adjust the scale of other if the scale of self is set (or no scales)
if self.scale is not None or other.scale is None:
out = self.replicate()
if other.scale is not None:
other = getattr(other, self.scale)
else:
out = other.replicate()
jd1 = self._time.jd1 - other._time.jd1
jd2 = self._time.jd2 - other._time.jd2
out._time.jd1, out._time.jd2 = day_frac(jd1, jd2)
return out
def __neg__(self):
"""Negation of a `TimeDelta` object."""
new = self.copy()
new._time.jd1 = -self._time.jd1
new._time.jd2 = -self._time.jd2
return new
def __abs__(self):
"""Absolute value of a `TimeDelta` object."""
jd1, jd2 = self._time.jd1, self._time.jd2
negative = jd1 + jd2 < 0
new = self.copy()
new._time.jd1 = np.where(negative, -jd1, jd1)
new._time.jd2 = np.where(negative, -jd2, jd2)
return new
def __mul__(self, other):
"""Multiplication of `TimeDelta` objects by numbers/arrays."""
# check needed since otherwise the self.jd1 * other multiplication
# would enter here again (via __rmul__)
if isinstance(other, Time):
raise OperandTypeError(self, other, '*')
try: # convert to straight float if dimensionless quantity
other = other.to(1)
except Exception:
pass
try:
jd1, jd2 = day_frac(self.jd1, self.jd2, factor=other)
out = TimeDelta(jd1, jd2, format='jd', scale=self.scale)
except Exception as err: # try downgrading self to a quantity
try:
return self.to(u.day) * other
except Exception:
raise err
if self.format != 'jd':
out = out.replicate(format=self.format)
return out
def __rmul__(self, other):
"""Multiplication of numbers/arrays with `TimeDelta` objects."""
return self.__mul__(other)
def __div__(self, other):
"""Division of `TimeDelta` objects by numbers/arrays."""
return self.__truediv__(other)
def __rdiv__(self, other):
"""Division by `TimeDelta` objects of numbers/arrays."""
return self.__rtruediv__(other)
def __truediv__(self, other):
"""Division of `TimeDelta` objects by numbers/arrays."""
# cannot do __mul__(1./other) as that looses precision
try:
other = other.to(1)
except Exception:
pass
try: # convert to straight float if dimensionless quantity
jd1, jd2 = day_frac(self.jd1, self.jd2, divisor=other)
out = TimeDelta(jd1, jd2, format='jd', scale=self.scale)
except Exception as err: # try downgrading self to a quantity
try:
return self.to(u.day) / other
except Exception:
raise err
if self.format != 'jd':
out = out.replicate(format=self.format)
return out
def __rtruediv__(self, other):
"""Division by `TimeDelta` objects of numbers/arrays."""
return other / self.to(u.day)
def to(self, *args, **kwargs):
return u.Quantity(self._time.jd1 + self._time.jd2,
u.day).to(*args, **kwargs)
def _make_value_equivalent(self, item, value):
"""Coerce setitem value into an equivalent TimeDelta object"""
if not isinstance(value, TimeDelta):
try:
value = self.__class__(value, scale=self.scale)
except Exception:
try:
value = self.__class__(value, scale=self.scale, format=self.format)
except Exception as err:
raise ValueError('cannot convert value to a compatible TimeDelta '
'object: {}'.format(err))
return value
class ScaleValueError(Exception):
pass
def _make_array(val, copy=False):
"""
Take ``val`` and convert/reshape to an array. If ``copy`` is `True`
then copy input values.
Returns
-------
val : ndarray
Array version of ``val``.
"""
val = np.array(val, copy=copy, subok=True)
# Allow only float64, string or object arrays as input
# (object is for datetime, maybe add more specific test later?)
# This also ensures the right byteorder for float64 (closes #2942).
if not (val.dtype == np.float64 or val.dtype.kind in 'OSUa'):
val = np.asanyarray(val, dtype=np.float64)
return val
def _check_for_masked_and_fill(val, val2):
"""
If ``val`` or ``val2`` are masked arrays then fill them and cast
to ndarray.
Returns a mask corresponding to the logical-or of masked elements
in ``val`` and ``val2``. If neither is masked then the return ``mask``
is ``None``.
If either ``val`` or ``val2`` are masked then they are replaced
with filled versions of themselves.
Parameters
----------
val : ndarray or MaskedArray
Input val
val2 : ndarray or MaskedArray
Input val2
Returns
-------
mask, val, val2: ndarray or None
Mask: (None or bool ndarray), val, val2: ndarray
"""
def get_as_filled_ndarray(mask, val):
"""
Fill the given MaskedArray ``val`` from the first non-masked
element in the array. This ensures that upstream Time initialization
will succeed.
Note that nothing happens if there are no masked elements.
"""
fill_value = None
if np.any(val.mask):
# Final mask is the logical-or of inputs
mask = mask | val.mask
# First unmasked element. If all elements are masked then
# use fill_value=None from above which will use val.fill_value.
# As long as the user has set this appropriately then all will
# be fine.
val_unmasked = val.compressed() # 1-d ndarray of unmasked values
if len(val_unmasked) > 0:
fill_value = val_unmasked[0]
# Fill the input ``val``. If fill_value is None then this just returns
# an ndarray view of val (no copy).
val = val.filled(fill_value)
return mask, val
mask = False
if isinstance(val, np.ma.MaskedArray):
mask, val = get_as_filled_ndarray(mask, val)
if isinstance(val2, np.ma.MaskedArray):
mask, val2 = get_as_filled_ndarray(mask, val2)
return mask, val, val2
class OperandTypeError(TypeError):
def __init__(self, left, right, op=None):
op_string = '' if op is None else ' for {0}'.format(op)
super().__init__(
"Unsupported operand type(s){0}: "
"'{1}' and '{2}'".format(op_string,
left.__class__.__name__,
right.__class__.__name__))
|
a3c5e37f7199380d0243f348fc06b5553214b7a71a429636412c8f77f9f03ec0 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
from .formats import *
from .core import *
|
ee3290b62e1ef54c315362e5d6e336dabb108d3b3044cbee9a54e14cfb1e782a | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""Time utilities.
In particular, routines to do basic arithmetic on numbers represented by two
doubles, using the procedure of Shewchuk, 1997, Discrete & Computational
Geometry 18(3):305-363 -- http://www.cs.berkeley.edu/~jrs/papers/robustr.pdf
"""
import numpy as np
def day_frac(val1, val2, factor=1., divisor=1.):
"""
Return the sum of ``val1`` and ``val2`` as two float64s, an integer part
and the fractional remainder. If ``factor`` is not 1.0 then multiply the
sum by ``factor``. If ``divisor`` is not 1.0 then divide the sum by
``divisor``.
The arithmetic is all done with exact floating point operations so no
precision is lost to rounding error. This routine assumes the sum is less
than about 1e16, otherwise the ``frac`` part will be greater than 1.0.
Returns
-------
day, frac : float64
Integer and fractional part of val1 + val2.
"""
# Add val1 and val2 exactly, returning the result as two float64s.
# The first is the approximate sum (with some floating point error)
# and the second is the error of the float64 sum.
sum12, err12 = two_sum(val1, val2)
if np.any(factor != 1.):
sum12, carry = two_product(sum12, factor)
carry += err12 * factor
sum12, err12 = two_sum(sum12, carry)
if np.any(divisor != 1.):
q1 = sum12 / divisor
p1, p2 = two_product(q1, divisor)
d1, d2 = two_sum(sum12, -p1)
d2 += err12
d2 -= p2
q2 = (d1 + d2) / divisor # 3-part float fine here; nothing can be lost
sum12, err12 = two_sum(q1, q2)
# get integer fraction
day = np.round(sum12)
extra, frac = two_sum(sum12, -day)
frac += extra + err12
return day, frac
def two_sum(a, b):
"""
Add ``a`` and ``b`` exactly, returning the result as two float64s.
The first is the approximate sum (with some floating point error)
and the second is the error of the float64 sum.
Using the procedure of Shewchuk, 1997,
Discrete & Computational Geometry 18(3):305-363
http://www.cs.berkeley.edu/~jrs/papers/robustr.pdf
Returns
-------
sum, err : float64
Approximate sum of a + b and the exact floating point error
"""
x = a + b
eb = x - a
eb = b - eb
ea = x - b
ea = a - ea
return x, ea + eb
def two_product(a, b):
"""
Multiple ``a`` and ``b`` exactly, returning the result as two float64s.
The first is the approximate product (with some floating point error)
and the second is the error of the float64 product.
Uses the procedure of Shewchuk, 1997,
Discrete & Computational Geometry 18(3):305-363
http://www.cs.berkeley.edu/~jrs/papers/robustr.pdf
Returns
-------
prod, err : float64
Approximate product a * b and the exact floating point error
"""
x = a * b
ah, al = split(a)
bh, bl = split(b)
y1 = ah * bh
y = x - y1
y2 = al * bh
y -= y2
y3 = ah * bl
y -= y3
y4 = al * bl
y = y4 - y
return x, y
def split(a):
"""
Split float64 in two aligned parts.
Uses the procedure of Shewchuk, 1997,
Discrete & Computational Geometry 18(3):305-363
http://www.cs.berkeley.edu/~jrs/papers/robustr.pdf
"""
c = 134217729. * a # 2**27+1.
abig = c - a
ah = c - abig
al = a - ah
return ah, al
|
010f5ae304e453501cb5889f35faac8aca55953fe720522f260e2574686c1e37 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
import fnmatch
import time
import re
import datetime
from collections import OrderedDict, defaultdict
import numpy as np
from ..utils.decorators import lazyproperty
from .. import units as u
from .. import _erfa as erfa
from .utils import day_frac, two_sum
__all__ = ['TimeFormat', 'TimeJD', 'TimeMJD', 'TimeFromEpoch', 'TimeUnix',
'TimeCxcSec', 'TimeGPS', 'TimeDecimalYear',
'TimePlotDate', 'TimeUnique', 'TimeDatetime', 'TimeString',
'TimeISO', 'TimeISOT', 'TimeFITS', 'TimeYearDayTime',
'TimeEpochDate', 'TimeBesselianEpoch', 'TimeJulianEpoch',
'TimeDeltaFormat', 'TimeDeltaSec', 'TimeDeltaJD',
'TimeEpochDateString', 'TimeBesselianEpochString',
'TimeJulianEpochString', 'TIME_FORMATS', 'TIME_DELTA_FORMATS',
'TimezoneInfo']
__doctest_skip__ = ['TimePlotDate']
# These both get filled in at end after TimeFormat subclasses defined.
# Use an OrderedDict to fix the order in which formats are tried.
# This ensures, e.g., that 'isot' gets tried before 'fits'.
TIME_FORMATS = OrderedDict()
TIME_DELTA_FORMATS = OrderedDict()
# Translations between deprecated FITS timescales defined by
# Rots et al. 2015, A&A 574:A36, and timescales used here.
FITS_DEPRECATED_SCALES = {'TDT': 'tt', 'ET': 'tt',
'GMT': 'utc', 'UT': 'utc', 'IAT': 'tai'}
def _regexify_subfmts(subfmts):
"""
Iterate through each of the sub-formats and try substituting simple
regular expressions for the strptime codes for year, month, day-of-month,
hour, minute, second. If no % characters remain then turn the final string
into a compiled regex. This assumes time formats do not have a % in them.
This is done both to speed up parsing of strings and to allow mixed formats
where strptime does not quite work well enough.
"""
new_subfmts = []
for subfmt_tuple in subfmts:
subfmt_in = subfmt_tuple[1]
for strptime_code, regex in (('%Y', r'(?P<year>\d\d\d\d)'),
('%m', r'(?P<mon>\d{1,2})'),
('%d', r'(?P<mday>\d{1,2})'),
('%H', r'(?P<hour>\d{1,2})'),
('%M', r'(?P<min>\d{1,2})'),
('%S', r'(?P<sec>\d{1,2})')):
subfmt_in = subfmt_in.replace(strptime_code, regex)
if '%' not in subfmt_in:
subfmt_tuple = (subfmt_tuple[0],
re.compile(subfmt_in + '$'),
subfmt_tuple[2])
new_subfmts.append(subfmt_tuple)
return tuple(new_subfmts)
class TimeFormatMeta(type):
"""
Metaclass that adds `TimeFormat` and `TimeDeltaFormat` to the
`TIME_FORMATS` and `TIME_DELTA_FORMATS` registries, respectively.
"""
_registry = TIME_FORMATS
def __new__(mcls, name, bases, members):
cls = super().__new__(mcls, name, bases, members)
# Register time formats that have a name, but leave out astropy_time since
# it is not a user-accessible format and is only used for initialization into
# a different format.
if 'name' in members and cls.name != 'astropy_time':
mcls._registry[cls.name] = cls
if 'subfmts' in members:
cls.subfmts = _regexify_subfmts(members['subfmts'])
return cls
class TimeFormat(metaclass=TimeFormatMeta):
"""
Base class for time representations.
Parameters
----------
val1 : numpy ndarray, list, number, str, or bytes
Values to initialize the time or times. Bytes are decoded as ascii.
val2 : numpy ndarray, list, or number; optional
Value(s) to initialize the time or times. Only used for numerical
input, to help preserve precision.
scale : str
Time scale of input value(s)
precision : int
Precision for seconds as floating point
in_subfmt : str
Select subformat for inputting string times
out_subfmt : str
Select subformat for outputting string times
from_jd : bool
If true then val1, val2 are jd1, jd2
"""
def __init__(self, val1, val2, scale, precision,
in_subfmt, out_subfmt, from_jd=False):
self.scale = scale # validation of scale done later with _check_scale
self.precision = precision
self.in_subfmt = in_subfmt
self.out_subfmt = out_subfmt
if from_jd:
self.jd1 = val1
self.jd2 = val2
else:
val1, val2 = self._check_val_type(val1, val2)
self.set_jds(val1, val2)
def __len__(self):
return len(self.jd1)
@property
def scale(self):
"""Time scale"""
self._scale = self._check_scale(self._scale)
return self._scale
@scale.setter
def scale(self, val):
self._scale = val
def mask_if_needed(self, value):
if self.masked:
value = np.ma.array(value, mask=self.mask, copy=False)
return value
@property
def mask(self):
if 'mask' not in self.cache:
self.cache['mask'] = np.isnan(self.jd2)
if self.cache['mask'].shape:
self.cache['mask'].flags.writeable = False
return self.cache['mask']
@property
def masked(self):
if 'masked' not in self.cache:
self.cache['masked'] = bool(np.any(self.mask))
return self.cache['masked']
@property
def jd2_filled(self):
return np.nan_to_num(self.jd2) if self.masked else self.jd2
@lazyproperty
def cache(self):
"""
Return the cache associated with this instance.
"""
return defaultdict(dict)
def _check_val_type(self, val1, val2):
"""Input value validation, typically overridden by derived classes"""
# val1 cannot contain nan, but val2 can contain nan
ok1 = val1.dtype == np.double and np.all(np.isfinite(val1))
ok2 = val2 is None or (val2.dtype == np.double and not np.any(np.isinf(val2)))
if not (ok1 and ok2):
raise TypeError('Input values for {0} class must be finite doubles'
.format(self.name))
if getattr(val1, 'unit', None) is not None:
# Possibly scaled unit any quantity-likes should be converted to
_unit = u.CompositeUnit(getattr(self, 'unit', 1.), [u.day], [1])
val1 = u.Quantity(val1, copy=False).to_value(_unit)
if val2 is not None:
val2 = u.Quantity(val2, copy=False).to_value(_unit)
elif getattr(val2, 'unit', None) is not None:
raise TypeError('Cannot mix float and Quantity inputs')
if val2 is None:
val2 = np.zeros_like(val1)
def asarray_or_scalar(val):
"""
Remove ndarray subclasses since for jd1/jd2 we want a pure ndarray
or a Python or numpy scalar.
"""
return np.asarray(val) if isinstance(val, np.ndarray) else val
return asarray_or_scalar(val1), asarray_or_scalar(val2)
def _check_scale(self, scale):
"""
Return a validated scale value.
If there is a class attribute 'scale' then that defines the default /
required time scale for this format. In this case if a scale value was
provided that needs to match the class default, otherwise return
the class default.
Otherwise just make sure that scale is in the allowed list of
scales. Provide a different error message if `None` (no value) was
supplied.
"""
if hasattr(self.__class__, 'epoch_scale') and scale is None:
scale = self.__class__.epoch_scale
if scale is None:
scale = 'utc' # Default scale as of astropy 0.4
if scale not in TIME_SCALES:
raise ScaleValueError("Scale value '{0}' not in "
"allowed values {1}"
.format(scale, TIME_SCALES))
return scale
def set_jds(self, val1, val2):
"""
Set internal jd1 and jd2 from val1 and val2. Must be provided
by derived classes.
"""
raise NotImplementedError
def to_value(self, parent=None):
"""
Return time representation from internal jd1 and jd2. This is
the base method that ignores ``parent`` and requires that
subclasses implement the ``value`` property. Subclasses that
require ``parent`` or have other optional args for ``to_value``
should compute and return the value directly.
"""
return self.mask_if_needed(self.value)
@property
def value(self):
raise NotImplementedError
class TimeJD(TimeFormat):
"""
Julian Date time format.
This represents the number of days since the beginning of
the Julian Period.
For example, 2451544.5 in JD is midnight on January 1, 2000.
"""
name = 'jd'
def set_jds(self, val1, val2):
self._check_scale(self._scale) # Validate scale.
self.jd1, self.jd2 = day_frac(val1, val2)
@property
def value(self):
return self.jd1 + self.jd2
class TimeMJD(TimeFormat):
"""
Modified Julian Date time format.
This represents the number of days since midnight on November 17, 1858.
For example, 51544.0 in MJD is midnight on January 1, 2000.
"""
name = 'mjd'
def set_jds(self, val1, val2):
# TODO - this routine and vals should be Cythonized to follow the ERFA
# convention of preserving precision by adding to the larger of the two
# values in a vectorized operation. But in most practical cases the
# first one is probably biggest.
self._check_scale(self._scale) # Validate scale.
jd1, jd2 = day_frac(val1, val2)
jd1 += erfa.DJM0 # erfa.DJM0=2400000.5 (from erfam.h)
self.jd1, self.jd2 = day_frac(jd1, jd2)
@property
def value(self):
return (self.jd1 - erfa.DJM0) + self.jd2
class TimeDecimalYear(TimeFormat):
"""
Time as a decimal year, with integer values corresponding to midnight
of the first day of each year. For example 2000.5 corresponds to the
ISO time '2000-07-02 00:00:00'.
"""
name = 'decimalyear'
def set_jds(self, val1, val2):
self._check_scale(self._scale) # Validate scale.
sum12, err12 = two_sum(val1, val2)
iy_start = np.trunc(sum12).astype(int)
extra, y_frac = two_sum(sum12, -iy_start)
y_frac += extra + err12
val = (val1 + val2).astype(np.double)
iy_start = np.trunc(val).astype(int)
imon = np.ones_like(iy_start)
iday = np.ones_like(iy_start)
ihr = np.zeros_like(iy_start)
imin = np.zeros_like(iy_start)
isec = np.zeros_like(y_frac)
# Possible enhancement: use np.unique to only compute start, stop
# for unique values of iy_start.
scale = self.scale.upper().encode('ascii')
jd1_start, jd2_start = erfa.dtf2d(scale, iy_start, imon, iday,
ihr, imin, isec)
jd1_end, jd2_end = erfa.dtf2d(scale, iy_start + 1, imon, iday,
ihr, imin, isec)
t_start = Time(jd1_start, jd2_start, scale=self.scale, format='jd')
t_end = Time(jd1_end, jd2_end, scale=self.scale, format='jd')
t_frac = t_start + (t_end - t_start) * y_frac
self.jd1, self.jd2 = day_frac(t_frac.jd1, t_frac.jd2)
@property
def value(self):
scale = self.scale.upper().encode('ascii')
iy_start, ims, ids, ihmsfs = erfa.d2dtf(scale, 0, # precision=0
self.jd1, self.jd2_filled)
imon = np.ones_like(iy_start)
iday = np.ones_like(iy_start)
ihr = np.zeros_like(iy_start)
imin = np.zeros_like(iy_start)
isec = np.zeros_like(self.jd1)
# Possible enhancement: use np.unique to only compute start, stop
# for unique values of iy_start.
scale = self.scale.upper().encode('ascii')
jd1_start, jd2_start = erfa.dtf2d(scale, iy_start, imon, iday,
ihr, imin, isec)
jd1_end, jd2_end = erfa.dtf2d(scale, iy_start + 1, imon, iday,
ihr, imin, isec)
dt = (self.jd1 - jd1_start) + (self.jd2 - jd2_start)
dt_end = (jd1_end - jd1_start) + (jd2_end - jd2_start)
decimalyear = iy_start + dt / dt_end
return decimalyear
class TimeFromEpoch(TimeFormat):
"""
Base class for times that represent the interval from a particular
epoch as a floating point multiple of a unit time interval (e.g. seconds
or days).
"""
def __init__(self, val1, val2, scale, precision,
in_subfmt, out_subfmt, from_jd=False):
self.scale = scale
# Initialize the reference epoch (a single time defined in subclasses)
epoch = Time(self.epoch_val, self.epoch_val2, scale=self.epoch_scale,
format=self.epoch_format)
self.epoch = epoch
# Now create the TimeFormat object as normal
super().__init__(val1, val2, scale, precision, in_subfmt, out_subfmt,
from_jd)
def set_jds(self, val1, val2):
"""
Initialize the internal jd1 and jd2 attributes given val1 and val2.
For an TimeFromEpoch subclass like TimeUnix these will be floats giving
the effective seconds since an epoch time (e.g. 1970-01-01 00:00:00).
"""
# Form new JDs based on epoch time + time from epoch (converted to JD).
# One subtlety that might not be obvious is that 1.000 Julian days in
# UTC can be 86400 or 86401 seconds. For the TimeUnix format the
# assumption is that every day is exactly 86400 seconds, so this is, in
# principle, doing the math incorrectly, *except* that it matches the
# definition of Unix time which does not include leap seconds.
# note: use divisor=1./self.unit, since this is either 1 or 1/86400,
# and 1/86400 is not exactly representable as a float64, so multiplying
# by that will cause rounding errors. (But inverting it as a float64
# recovers the exact number)
day, frac = day_frac(val1, val2, divisor=1. / self.unit)
jd1 = self.epoch.jd1 + day
jd2 = self.epoch.jd2 + frac
# Create a temporary Time object corresponding to the new (jd1, jd2) in
# the epoch scale (e.g. UTC for TimeUnix) then convert that to the
# desired time scale for this object.
#
# A known limitation is that the transform from self.epoch_scale to
# self.scale cannot involve any metadata like lat or lon.
try:
tm = getattr(Time(jd1, jd2, scale=self.epoch_scale,
format='jd'), self.scale)
except Exception as err:
raise ScaleValueError("Cannot convert from '{0}' epoch scale '{1}'"
"to specified scale '{2}', got error:\n{3}"
.format(self.name, self.epoch_scale,
self.scale, err))
self.jd1, self.jd2 = day_frac(tm._time.jd1, tm._time.jd2)
def to_value(self, parent=None):
# Make sure that scale is the same as epoch scale so we can just
# subtract the epoch and convert
if self.scale != self.epoch_scale:
if parent is None:
raise ValueError('cannot compute value without parent Time object')
tm = getattr(parent, self.epoch_scale)
jd1, jd2 = tm._time.jd1, tm._time.jd2
else:
jd1, jd2 = self.jd1, self.jd2
time_from_epoch = ((jd1 - self.epoch.jd1) +
(jd2 - self.epoch.jd2)) / self.unit
return self.mask_if_needed(time_from_epoch)
value = property(to_value)
class TimeUnix(TimeFromEpoch):
"""
Unix time: seconds from 1970-01-01 00:00:00 UTC.
For example, 946684800.0 in Unix time is midnight on January 1, 2000.
NOTE: this quantity is not exactly unix time and differs from the strict
POSIX definition by up to 1 second on days with a leap second. POSIX
unix time actually jumps backward by 1 second at midnight on leap second
days while this class value is monotonically increasing at 86400 seconds
per UTC day.
"""
name = 'unix'
unit = 1.0 / erfa.DAYSEC # in days (1 day == 86400 seconds)
epoch_val = '1970-01-01 00:00:00'
epoch_val2 = None
epoch_scale = 'utc'
epoch_format = 'iso'
class TimeCxcSec(TimeFromEpoch):
"""
Chandra X-ray Center seconds from 1998-01-01 00:00:00 TT.
For example, 63072064.184 is midnight on January 1, 2000.
"""
name = 'cxcsec'
unit = 1.0 / erfa.DAYSEC # in days (1 day == 86400 seconds)
epoch_val = '1998-01-01 00:00:00'
epoch_val2 = None
epoch_scale = 'tt'
epoch_format = 'iso'
class TimeGPS(TimeFromEpoch):
"""GPS time: seconds from 1980-01-06 00:00:00 UTC
For example, 630720013.0 is midnight on January 1, 2000.
Notes
=====
This implementation is strictly a representation of the number of seconds
(including leap seconds) since midnight UTC on 1980-01-06. GPS can also be
considered as a time scale which is ahead of TAI by a fixed offset
(to within about 100 nanoseconds).
For details, see http://tycho.usno.navy.mil/gpstt.html
"""
name = 'gps'
unit = 1.0 / erfa.DAYSEC # in days (1 day == 86400 seconds)
epoch_val = '1980-01-06 00:00:19'
# above epoch is the same as Time('1980-01-06 00:00:00', scale='utc').tai
epoch_val2 = None
epoch_scale = 'tai'
epoch_format = 'iso'
class TimePlotDate(TimeFromEpoch):
"""
Matplotlib `~matplotlib.pyplot.plot_date` input:
1 + number of days from 0001-01-01 00:00:00 UTC
This can be used directly in the matplotlib `~matplotlib.pyplot.plot_date`
function::
>>> import matplotlib.pyplot as plt
>>> jyear = np.linspace(2000, 2001, 20)
>>> t = Time(jyear, format='jyear', scale='utc')
>>> plt.plot_date(t.plot_date, jyear)
>>> plt.gcf().autofmt_xdate() # orient date labels at a slant
>>> plt.draw()
For example, 730120.0003703703 is midnight on January 1, 2000.
"""
# This corresponds to the zero reference time for matplotlib plot_date().
# Note that TAI and UTC are equivalent at the reference time.
name = 'plot_date'
unit = 1.0
epoch_val = 1721424.5 # Time('0001-01-01 00:00:00', scale='tai').jd - 1
epoch_val2 = None
epoch_scale = 'utc'
epoch_format = 'jd'
class TimeUnique(TimeFormat):
"""
Base class for time formats that can uniquely create a time object
without requiring an explicit format specifier. This class does
nothing but provide inheritance to identify a class as unique.
"""
class TimeAstropyTime(TimeUnique):
"""
Instantiate date from an Astropy Time object (or list thereof).
This is purely for instantiating from a Time object. The output
format is the same as the first time instance.
"""
name = 'astropy_time'
def __new__(cls, val1, val2, scale, precision,
in_subfmt, out_subfmt, from_jd=False):
"""
Use __new__ instead of __init__ to output a class instance that
is the same as the class of the first Time object in the list.
"""
val1_0 = val1.flat[0]
if not (isinstance(val1_0, Time) and all(type(val) is type(val1_0)
for val in val1.flat)):
raise TypeError('Input values for {0} class must all be same '
'astropy Time type.'.format(cls.name))
if scale is None:
scale = val1_0.scale
if val1.shape:
vals = [getattr(val, scale)._time for val in val1]
jd1 = np.concatenate([np.atleast_1d(val.jd1) for val in vals])
jd2 = np.concatenate([np.atleast_1d(val.jd2) for val in vals])
else:
val = getattr(val1_0, scale)._time
jd1, jd2 = val.jd1, val.jd2
OutTimeFormat = val1_0._time.__class__
self = OutTimeFormat(jd1, jd2, scale, precision, in_subfmt, out_subfmt,
from_jd=True)
return self
class TimeDatetime(TimeUnique):
"""
Represent date as Python standard library `~datetime.datetime` object
Example::
>>> from astropy.time import Time
>>> from datetime import datetime
>>> t = Time(datetime(2000, 1, 2, 12, 0, 0), scale='utc')
>>> t.iso
'2000-01-02 12:00:00.000'
>>> t.tt.datetime
datetime.datetime(2000, 1, 2, 12, 1, 4, 184000)
"""
name = 'datetime'
def _check_val_type(self, val1, val2):
# Note: don't care about val2 for this class
if not all(isinstance(val, datetime.datetime) for val in val1.flat):
raise TypeError('Input values for {0} class must be '
'datetime objects'.format(self.name))
return val1, None
def set_jds(self, val1, val2):
"""Convert datetime object contained in val1 to jd1, jd2"""
# Iterate through the datetime objects, getting year, month, etc.
iterator = np.nditer([val1, None, None, None, None, None, None],
flags=['refs_ok'],
op_dtypes=[object] + 5*[np.intc] + [np.double])
for val, iy, im, id, ihr, imin, dsec in iterator:
dt = val.item()
if dt.tzinfo is not None:
dt = (dt - dt.utcoffset()).replace(tzinfo=None)
iy[...] = dt.year
im[...] = dt.month
id[...] = dt.day
ihr[...] = dt.hour
imin[...] = dt.minute
dsec[...] = dt.second + dt.microsecond / 1e6
jd1, jd2 = erfa.dtf2d(self.scale.upper().encode('ascii'),
*iterator.operands[1:])
self.jd1, self.jd2 = day_frac(jd1, jd2)
def to_value(self, timezone=None, parent=None):
"""
Convert to (potentially timezone-aware) `~datetime.datetime` object.
If ``timezone`` is not ``None``, return a timezone-aware datetime
object.
Parameters
----------
timezone : {`~datetime.tzinfo`, None} (optional)
If not `None`, return timezone-aware datetime.
Returns
-------
`~datetime.datetime`
If ``timezone`` is not ``None``, output will be timezone-aware.
"""
if timezone is not None:
if self._scale != 'utc':
raise ScaleValueError("scale is {}, must be 'utc' when timezone "
"is supplied.".format(self._scale))
# Rather than define a value property directly, we have a function,
# since we want to be able to pass in timezone information.
scale = self.scale.upper().encode('ascii')
iys, ims, ids, ihmsfs = erfa.d2dtf(scale, 6, # 6 for microsec
self.jd1, self.jd2_filled)
ihrs = ihmsfs[..., 0]
imins = ihmsfs[..., 1]
isecs = ihmsfs[..., 2]
ifracs = ihmsfs[..., 3]
iterator = np.nditer([iys, ims, ids, ihrs, imins, isecs, ifracs, None],
flags=['refs_ok'],
op_dtypes=7*[iys.dtype] + [object])
for iy, im, id, ihr, imin, isec, ifracsec, out in iterator:
if isec >= 60:
raise ValueError('Time {} is within a leap second but datetime '
'does not support leap seconds'
.format((iy, im, id, ihr, imin, isec, ifracsec)))
if timezone is not None:
out[...] = datetime.datetime(iy, im, id, ihr, imin, isec, ifracsec,
tzinfo=TimezoneInfo()).astimezone(timezone)
else:
out[...] = datetime.datetime(iy, im, id, ihr, imin, isec, ifracsec)
return self.mask_if_needed(iterator.operands[-1])
value = property(to_value)
class TimezoneInfo(datetime.tzinfo):
"""
Subclass of the `~datetime.tzinfo` object, used in the
to_datetime method to specify timezones.
It may be safer in most cases to use a timezone database package like
pytz rather than defining your own timezones - this class is mainly
a workaround for users without pytz.
"""
@u.quantity_input(utc_offset=u.day, dst=u.day)
def __init__(self, utc_offset=0*u.day, dst=0*u.day, tzname=None):
"""
Parameters
----------
utc_offset : `~astropy.units.Quantity` (optional)
Offset from UTC in days. Defaults to zero.
dst : `~astropy.units.Quantity` (optional)
Daylight Savings Time offset in days. Defaults to zero
(no daylight savings).
tzname : string, `None` (optional)
Name of timezone
Examples
--------
>>> from datetime import datetime
>>> from astropy.time import TimezoneInfo # Specifies a timezone
>>> import astropy.units as u
>>> utc = TimezoneInfo() # Defaults to UTC
>>> utc_plus_one_hour = TimezoneInfo(utc_offset=1*u.hour) # UTC+1
>>> dt_aware = datetime(2000, 1, 1, 0, 0, 0, tzinfo=utc_plus_one_hour)
>>> print(dt_aware)
2000-01-01 00:00:00+01:00
>>> print(dt_aware.astimezone(utc))
1999-12-31 23:00:00+00:00
"""
if utc_offset == 0 and dst == 0 and tzname is None:
tzname = 'UTC'
self._utcoffset = datetime.timedelta(utc_offset.to_value(u.day))
self._tzname = tzname
self._dst = datetime.timedelta(dst.to_value(u.day))
def utcoffset(self, dt):
return self._utcoffset
def tzname(self, dt):
return str(self._tzname)
def dst(self, dt):
return self._dst
class TimeString(TimeUnique):
"""
Base class for string-like time representations.
This class assumes that anything following the last decimal point to the
right is a fraction of a second.
This is a reference implementation can be made much faster with effort.
"""
def _check_val_type(self, val1, val2):
# Note: don't care about val2 for these classes
if val1.dtype.kind not in ('S', 'U'):
raise TypeError('Input values for {0} class must be strings'
.format(self.name))
return val1, None
def parse_string(self, timestr, subfmts):
"""Read time from a single string, using a set of possible formats."""
# Datetime components required for conversion to JD by ERFA, along
# with the default values.
components = ('year', 'mon', 'mday', 'hour', 'min', 'sec')
defaults = (None, 1, 1, 0, 0, 0)
# Assume that anything following "." on the right side is a
# floating fraction of a second.
try:
idot = timestr.rindex('.')
except Exception:
fracsec = 0.0
else:
timestr, fracsec = timestr[:idot], timestr[idot:]
fracsec = float(fracsec)
for _, strptime_fmt_or_regex, _ in subfmts:
if isinstance(strptime_fmt_or_regex, str):
try:
tm = time.strptime(timestr, strptime_fmt_or_regex)
except ValueError:
continue
else:
vals = [getattr(tm, 'tm_' + component)
for component in components]
else:
tm = re.match(strptime_fmt_or_regex, timestr)
if tm is None:
continue
tm = tm.groupdict()
vals = [int(tm.get(component, default)) for component, default
in zip(components, defaults)]
# Add fractional seconds
vals[-1] = vals[-1] + fracsec
return vals
else:
raise ValueError('Time {0} does not match {1} format'
.format(timestr, self.name))
def set_jds(self, val1, val2):
"""Parse the time strings contained in val1 and set jd1, jd2"""
# Select subformats based on current self.in_subfmt
subfmts = self._select_subfmts(self.in_subfmt)
# Be liberal in what we accept: convert bytes to ascii.
# Here .item() is needed for arrays with entries of unequal length,
# to strip trailing 0 bytes.
to_string = (str if val1.dtype.kind == 'U' else
lambda x: str(x.item(), encoding='ascii'))
iterator = np.nditer([val1, None, None, None, None, None, None],
op_dtypes=[val1.dtype] + 5*[np.intc] + [np.double])
for val, iy, im, id, ihr, imin, dsec in iterator:
val = to_string(val)
iy[...], im[...], id[...], ihr[...], imin[...], dsec[...] = (
self.parse_string(val, subfmts))
jd1, jd2 = erfa.dtf2d(self.scale.upper().encode('ascii'),
*iterator.operands[1:])
self.jd1, self.jd2 = day_frac(jd1, jd2)
def str_kwargs(self):
"""
Generator that yields a dict of values corresponding to the
calendar date and time for the internal JD values.
"""
scale = self.scale.upper().encode('ascii'),
iys, ims, ids, ihmsfs = erfa.d2dtf(scale, self.precision,
self.jd1, self.jd2_filled)
# Get the str_fmt element of the first allowed output subformat
_, _, str_fmt = self._select_subfmts(self.out_subfmt)[0]
if '{yday:' in str_fmt:
has_yday = True
else:
has_yday = False
yday = None
ihrs = ihmsfs[..., 0]
imins = ihmsfs[..., 1]
isecs = ihmsfs[..., 2]
ifracs = ihmsfs[..., 3]
for iy, im, id, ihr, imin, isec, ifracsec in np.nditer(
[iys, ims, ids, ihrs, imins, isecs, ifracs]):
if has_yday:
yday = datetime.datetime(iy, im, id).timetuple().tm_yday
yield {'year': int(iy), 'mon': int(im), 'day': int(id),
'hour': int(ihr), 'min': int(imin), 'sec': int(isec),
'fracsec': int(ifracsec), 'yday': yday}
def format_string(self, str_fmt, **kwargs):
"""Write time to a string using a given format.
By default, just interprets str_fmt as a format string,
but subclasses can add to this.
"""
return str_fmt.format(**kwargs)
@property
def value(self):
# Select the first available subformat based on current
# self.out_subfmt
subfmts = self._select_subfmts(self.out_subfmt)
_, _, str_fmt = subfmts[0]
# TODO: fix this ugly hack
if self.precision > 0 and str_fmt.endswith('{sec:02d}'):
str_fmt += '.{fracsec:0' + str(self.precision) + 'd}'
# Try to optimize this later. Can't pre-allocate because length of
# output could change, e.g. year rolls from 999 to 1000.
outs = []
for kwargs in self.str_kwargs():
outs.append(str(self.format_string(str_fmt, **kwargs)))
return np.array(outs).reshape(self.jd1.shape)
def _select_subfmts(self, pattern):
"""
Return a list of subformats where name matches ``pattern`` using
fnmatch.
"""
fnmatchcase = fnmatch.fnmatchcase
subfmts = [x for x in self.subfmts if fnmatchcase(x[0], pattern)]
if len(subfmts) == 0:
raise ValueError('No subformats match {0}'.format(pattern))
return subfmts
class TimeISO(TimeString):
"""
ISO 8601 compliant date-time format "YYYY-MM-DD HH:MM:SS.sss...".
For example, 2000-01-01 00:00:00.000 is midnight on January 1, 2000.
The allowed subformats are:
- 'date_hms': date + hours, mins, secs (and optional fractional secs)
- 'date_hm': date + hours, mins
- 'date': date
"""
name = 'iso'
subfmts = (('date_hms',
'%Y-%m-%d %H:%M:%S',
# XXX To Do - use strftime for output ??
'{year:d}-{mon:02d}-{day:02d} {hour:02d}:{min:02d}:{sec:02d}'),
('date_hm',
'%Y-%m-%d %H:%M',
'{year:d}-{mon:02d}-{day:02d} {hour:02d}:{min:02d}'),
('date',
'%Y-%m-%d',
'{year:d}-{mon:02d}-{day:02d}'))
def parse_string(self, timestr, subfmts):
# Handle trailing 'Z' for UTC time
if timestr.endswith('Z'):
if self.scale != 'utc':
raise ValueError("Time input terminating in 'Z' must have "
"scale='UTC'")
timestr = timestr[:-1]
return super().parse_string(timestr, subfmts)
class TimeISOT(TimeISO):
"""
ISO 8601 compliant date-time format "YYYY-MM-DDTHH:MM:SS.sss...".
This is the same as TimeISO except for a "T" instead of space between
the date and time.
For example, 2000-01-01T00:00:00.000 is midnight on January 1, 2000.
The allowed subformats are:
- 'date_hms': date + hours, mins, secs (and optional fractional secs)
- 'date_hm': date + hours, mins
- 'date': date
"""
name = 'isot'
subfmts = (('date_hms',
'%Y-%m-%dT%H:%M:%S',
'{year:d}-{mon:02d}-{day:02d}T{hour:02d}:{min:02d}:{sec:02d}'),
('date_hm',
'%Y-%m-%dT%H:%M',
'{year:d}-{mon:02d}-{day:02d}T{hour:02d}:{min:02d}'),
('date',
'%Y-%m-%d',
'{year:d}-{mon:02d}-{day:02d}'))
class TimeYearDayTime(TimeISO):
"""
Year, day-of-year and time as "YYYY:DOY:HH:MM:SS.sss...".
The day-of-year (DOY) goes from 001 to 365 (366 in leap years).
For example, 2000:001:00:00:00.000 is midnight on January 1, 2000.
The allowed subformats are:
- 'date_hms': date + hours, mins, secs (and optional fractional secs)
- 'date_hm': date + hours, mins
- 'date': date
"""
name = 'yday'
subfmts = (('date_hms',
'%Y:%j:%H:%M:%S',
'{year:d}:{yday:03d}:{hour:02d}:{min:02d}:{sec:02d}'),
('date_hm',
'%Y:%j:%H:%M',
'{year:d}:{yday:03d}:{hour:02d}:{min:02d}'),
('date',
'%Y:%j',
'{year:d}:{yday:03d}'))
class TimeFITS(TimeString):
"""
FITS format: "[±Y]YYYY-MM-DD[THH:MM:SS[.sss]][(SCALE[(REALIZATION)])]".
ISOT with two extensions:
- Can give signed five-digit year (mostly for negative years);
- A possible time scale (and realization) appended in parentheses.
Note: FITS supports some deprecated names for timescales; these are
translated to the formal names upon initialization. Furthermore, any
specific realization information is stored only as long as the time scale
is not changed.
The allowed subformats are:
- 'date_hms': date + hours, mins, secs (and optional fractional secs)
- 'date': date
- 'longdate_hms': as 'date_hms', but with signed 5-digit year
- 'longdate': as 'date', but with signed 5-digit year
See Rots et al., 2015, A&A 574:A36 (arXiv:1409.7583).
"""
name = 'fits'
subfmts = (
('date_hms',
(r'(?P<year>\d{4})-(?P<mon>\d\d)-(?P<mday>\d\d)T'
r'(?P<hour>\d\d):(?P<min>\d\d):(?P<sec>\d\d(\.\d*)?)'),
'{year:04d}-{mon:02d}-{day:02d}T{hour:02d}:{min:02d}:{sec:02d}'),
('date',
r'(?P<year>\d{4})-(?P<mon>\d\d)-(?P<mday>\d\d)',
'{year:04d}-{mon:02d}-{day:02d}'),
('longdate_hms',
(r'(?P<year>[+-]\d{5})-(?P<mon>\d\d)-(?P<mday>\d\d)T'
r'(?P<hour>\d\d):(?P<min>\d\d):(?P<sec>\d\d(\.\d*)?)'),
'{year:+06d}-{mon:02d}-{day:02d}T{hour:02d}:{min:02d}:{sec:02d}'),
('longdate',
r'(?P<year>[+-]\d{5})-(?P<mon>\d\d)-(?P<mday>\d\d)',
'{year:+06d}-{mon:02d}-{day:02d}'))
# Add the regex that parses the scale and possible realization.
subfmts = tuple(
(subfmt[0],
subfmt[1] + r'(\((?P<scale>\w+)(\((?P<realization>\w+)\))?\))?',
subfmt[2]) for subfmt in subfmts)
_fits_scale = None
_fits_realization = None
def parse_string(self, timestr, subfmts):
"""Read time and set scale according to trailing scale codes."""
# Try parsing with any of the allowed sub-formats.
for _, regex, _ in subfmts:
tm = re.match(regex, timestr)
if tm:
break
else:
raise ValueError('Time {0} does not match {1} format'
.format(timestr, self.name))
tm = tm.groupdict()
if tm['scale'] is not None:
# If a scale was given, translate from a possible deprecated
# timescale identifier to the scale used by Time.
fits_scale = tm['scale'].upper()
scale = FITS_DEPRECATED_SCALES.get(fits_scale, fits_scale.lower())
if scale not in TIME_SCALES:
raise ValueError("Scale {0!r} is not in the allowed scales {1}"
.format(scale, sorted(TIME_SCALES)))
# If no scale was given in the initialiser, set the scale to
# that given in the string. Also store a possible realization,
# so we can round-trip (as long as no scale changes are made).
fits_realization = (tm['realization'].upper()
if tm['realization'] else None)
if self._fits_scale is None:
self._fits_scale = fits_scale
self._fits_realization = fits_realization
if self._scale is None:
self._scale = scale
if (scale != self.scale or fits_scale != self._fits_scale or
fits_realization != self._fits_realization):
raise ValueError("Input strings for {0} class must all "
"have consistent time scales."
.format(self.name))
return [int(tm['year']), int(tm['mon']), int(tm['mday']),
int(tm.get('hour', 0)), int(tm.get('min', 0)),
float(tm.get('sec', 0.))]
def format_string(self, str_fmt, **kwargs):
"""Format time-string: append the scale to the normal ISOT format."""
time_str = super().format_string(str_fmt, **kwargs)
if self._fits_scale and self._fits_realization:
return '{0}({1}({2}))'.format(time_str, self._fits_scale,
self._fits_realization)
else:
return '{0}({1})'.format(time_str, self._scale.upper())
@property
def value(self):
"""Convert times to strings, using signed 5 digit if necessary."""
if 'long' not in self.out_subfmt:
# If we have times before year 0 or after year 9999, we can
# output only in a "long" format, using signed 5-digit years.
jd = self.jd1 + self.jd2
if jd.min() < 1721425.5 or jd.max() >= 5373484.5:
self.out_subfmt = 'long' + self.out_subfmt
return super().value
class TimeEpochDate(TimeFormat):
"""
Base class for support floating point Besselian and Julian epoch dates
"""
def set_jds(self, val1, val2):
self._check_scale(self._scale) # validate scale.
epoch_to_jd = getattr(erfa, self.epoch_to_jd)
jd1, jd2 = epoch_to_jd(val1 + val2)
self.jd1, self.jd2 = day_frac(jd1, jd2)
@property
def value(self):
jd_to_epoch = getattr(erfa, self.jd_to_epoch)
return jd_to_epoch(self.jd1, self.jd2)
class TimeBesselianEpoch(TimeEpochDate):
"""Besselian Epoch year as floating point value(s) like 1950.0"""
name = 'byear'
epoch_to_jd = 'epb2jd'
jd_to_epoch = 'epb'
def _check_val_type(self, val1, val2):
"""Input value validation, typically overridden by derived classes"""
if hasattr(val1, 'to') and hasattr(val1, 'unit'):
raise ValueError("Cannot use Quantities for 'byear' format, "
"as the interpretation would be ambiguous. "
"Use float with Besselian year instead. ")
return super()._check_val_type(val1, val2)
class TimeJulianEpoch(TimeEpochDate):
"""Julian Epoch year as floating point value(s) like 2000.0"""
name = 'jyear'
unit = erfa.DJY # 365.25, the Julian year, for conversion to quantities
epoch_to_jd = 'epj2jd'
jd_to_epoch = 'epj'
class TimeEpochDateString(TimeString):
"""
Base class to support string Besselian and Julian epoch dates
such as 'B1950.0' or 'J2000.0' respectively.
"""
def set_jds(self, val1, val2):
epoch_prefix = self.epoch_prefix
# Be liberal in what we accept: convert bytes to ascii.
to_string = (str if val1.dtype.kind == 'U' else
lambda x: str(x.item(), encoding='ascii'))
iterator = np.nditer([val1, None], op_dtypes=[val1.dtype, np.double])
for val, years in iterator:
try:
time_str = to_string(val)
epoch_type, year_str = time_str[0], time_str[1:]
year = float(year_str)
if epoch_type.upper() != epoch_prefix:
raise ValueError
except (IndexError, ValueError, UnicodeEncodeError):
raise ValueError('Time {0} does not match {1} format'
.format(time_str, self.name))
else:
years[...] = year
self._check_scale(self._scale) # validate scale.
epoch_to_jd = getattr(erfa, self.epoch_to_jd)
jd1, jd2 = epoch_to_jd(iterator.operands[-1])
self.jd1, self.jd2 = day_frac(jd1, jd2)
@property
def value(self):
jd_to_epoch = getattr(erfa, self.jd_to_epoch)
years = jd_to_epoch(self.jd1, self.jd2)
# Use old-style format since it is a factor of 2 faster
str_fmt = self.epoch_prefix + '%.' + str(self.precision) + 'f'
outs = [str_fmt % year for year in years.flat]
return np.array(outs).reshape(self.jd1.shape)
class TimeBesselianEpochString(TimeEpochDateString):
"""Besselian Epoch year as string value(s) like 'B1950.0'"""
name = 'byear_str'
epoch_to_jd = 'epb2jd'
jd_to_epoch = 'epb'
epoch_prefix = 'B'
class TimeJulianEpochString(TimeEpochDateString):
"""Julian Epoch year as string value(s) like 'J2000.0'"""
name = 'jyear_str'
epoch_to_jd = 'epj2jd'
jd_to_epoch = 'epj'
epoch_prefix = 'J'
class TimeDeltaFormatMeta(TimeFormatMeta):
_registry = TIME_DELTA_FORMATS
class TimeDeltaFormat(TimeFormat, metaclass=TimeDeltaFormatMeta):
"""Base class for time delta representations"""
def _check_scale(self, scale):
"""
Check that the scale is in the allowed list of scales, or is `None`
"""
if scale is not None and scale not in TIME_DELTA_SCALES:
raise ScaleValueError("Scale value '{0}' not in "
"allowed values {1}"
.format(scale, TIME_DELTA_SCALES))
return scale
def set_jds(self, val1, val2):
self._check_scale(self._scale) # Validate scale.
self.jd1, self.jd2 = day_frac(val1, val2, divisor=1./self.unit)
@property
def value(self):
return (self.jd1 + self.jd2) / self.unit
class TimeDeltaSec(TimeDeltaFormat):
"""Time delta in SI seconds"""
name = 'sec'
unit = 1. / erfa.DAYSEC # for quantity input
class TimeDeltaJD(TimeDeltaFormat):
"""Time delta in Julian days (86400 SI seconds)"""
name = 'jd'
unit = 1.
from .core import Time, TIME_SCALES, TIME_DELTA_SCALES, ScaleValueError
|
f70d081b536f685fd13fe69b0eeffefdd97407ca466efe657d93fd71eeab769c | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
__all__ = ['quantity_input']
import inspect
from ..utils.decorators import wraps
from ..utils.misc import isiterable
from .core import Unit, UnitsError, add_enabled_equivalencies
from .physical import _unit_physical_mapping
def _get_allowed_units(targets):
"""
From a list of target units (either as strings or unit objects) and physical
types, return a list of Unit objects.
"""
allowed_units = []
for target in targets:
try: # unit passed in as a string
target_unit = Unit(target)
except ValueError:
try: # See if the function writer specified a physical type
physical_type_id = _unit_physical_mapping[target]
except KeyError: # Function argument target is invalid
raise ValueError("Invalid unit or physical type '{0}'."
.format(target))
# get unit directly from physical type id
target_unit = Unit._from_physical_type_id(physical_type_id)
allowed_units.append(target_unit)
return allowed_units
def _validate_arg_value(param_name, func_name, arg, targets, equivalencies):
"""
Validates the object passed in to the wrapped function, ``arg``, with target
unit or physical type, ``target``.
"""
allowed_units = _get_allowed_units(targets)
for allowed_unit in allowed_units:
try:
is_equivalent = arg.unit.is_equivalent(allowed_unit,
equivalencies=equivalencies)
if is_equivalent:
break
except AttributeError: # Either there is no .unit or no .is_equivalent
if hasattr(arg, "unit"):
error_msg = "a 'unit' attribute without an 'is_equivalent' method"
else:
error_msg = "no 'unit' attribute"
raise TypeError("Argument '{0}' to function '{1}' has {2}. "
"You may want to pass in an astropy Quantity instead."
.format(param_name, func_name, error_msg))
else:
if len(targets) > 1:
raise UnitsError("Argument '{0}' to function '{1}' must be in units"
" convertible to one of: {2}."
.format(param_name, func_name,
[str(targ) for targ in targets]))
else:
raise UnitsError("Argument '{0}' to function '{1}' must be in units"
" convertible to '{2}'."
.format(param_name, func_name,
str(targets[0])))
class QuantityInput:
@classmethod
def as_decorator(cls, func=None, **kwargs):
r"""
A decorator for validating the units of arguments to functions.
Unit specifications can be provided as keyword arguments to the decorator,
or by using function annotation syntax. Arguments to the decorator
take precedence over any function annotations present.
A `~astropy.units.UnitsError` will be raised if the unit attribute of
the argument is not equivalent to the unit specified to the decorator
or in the annotation.
If the argument has no unit attribute, i.e. it is not a Quantity object, a
`ValueError` will be raised.
Where an equivalency is specified in the decorator, the function will be
executed with that equivalency in force.
Notes
-----
The checking of arguments inside variable arguments to a function is not
supported (i.e. \*arg or \**kwargs).
Examples
--------
.. code-block:: python
import astropy.units as u
@u.quantity_input(myangle=u.arcsec)
def myfunction(myangle):
return myangle**2
.. code-block:: python
import astropy.units as u
@u.quantity_input
def myfunction(myangle: u.arcsec):
return myangle**2
Also you can specify a return value annotation, which will
cause the function to always return a `~astropy.units.Quantity` in that
unit.
.. code-block:: python
import astropy.units as u
@u.quantity_input
def myfunction(myangle: u.arcsec) -> u.deg**2:
return myangle**2
Using equivalencies::
import astropy.units as u
@u.quantity_input(myenergy=u.eV, equivalencies=u.mass_energy())
def myfunction(myenergy):
return myenergy**2
"""
self = cls(**kwargs)
if func is not None and not kwargs:
return self(func)
else:
return self
def __init__(self, func=None, **kwargs):
self.equivalencies = kwargs.pop('equivalencies', [])
self.decorator_kwargs = kwargs
def __call__(self, wrapped_function):
# Extract the function signature for the function we are wrapping.
wrapped_signature = inspect.signature(wrapped_function)
# Define a new function to return in place of the wrapped one
@wraps(wrapped_function)
def wrapper(*func_args, **func_kwargs):
# Bind the arguments to our new function to the signature of the original.
bound_args = wrapped_signature.bind(*func_args, **func_kwargs)
# Iterate through the parameters of the original signature
for param in wrapped_signature.parameters.values():
# We do not support variable arguments (*args, **kwargs)
if param.kind in (inspect.Parameter.VAR_KEYWORD,
inspect.Parameter.VAR_POSITIONAL):
continue
# Catch the (never triggered) case where bind relied on a default value.
if param.name not in bound_args.arguments and param.default is not param.empty:
bound_args.arguments[param.name] = param.default
# Get the value of this parameter (argument to new function)
arg = bound_args.arguments[param.name]
# Get target unit or physical type, either from decorator kwargs
# or annotations
if param.name in self.decorator_kwargs:
targets = self.decorator_kwargs[param.name]
else:
targets = param.annotation
# If the targets is empty, then no target units or physical
# types were specified so we can continue to the next arg
if targets is inspect.Parameter.empty:
continue
# If the argument value is None, and the default value is None,
# pass through the None even if there is a target unit
if arg is None and param.default is None:
continue
# Here, we check whether multiple target unit/physical type's
# were specified in the decorator/annotation, or whether a
# single string (unit or physical type) or a Unit object was
# specified
if isinstance(targets, str) or not isiterable(targets):
valid_targets = [targets]
# Check for None in the supplied list of allowed units and, if
# present and the passed value is also None, ignore.
elif None in targets:
if arg is None:
continue
else:
valid_targets = [t for t in targets if t is not None]
else:
valid_targets = targets
# Now we loop over the allowed units/physical types and validate
# the value of the argument:
_validate_arg_value(param.name, wrapped_function.__name__,
arg, valid_targets, self.equivalencies)
# Call the original function with any equivalencies in force.
with add_enabled_equivalencies(self.equivalencies):
return_ = wrapped_function(*func_args, **func_kwargs)
if wrapped_signature.return_annotation is not inspect.Signature.empty:
return return_.to(wrapped_signature.return_annotation)
else:
return return_
return wrapper
quantity_input = QuantityInput.as_decorator
|
6788ec87c476eae976198a64ffa49cc009095c8f147dcf3d97c2ee5e020db45d | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This package defines colloquially used Imperial units. They are
available in the `astropy.units.imperial` namespace, but not in the
top-level `astropy.units` namespace, e.g.::
>>> import astropy.units as u
>>> mph = u.imperial.mile / u.hour
>>> mph
Unit("mi / h")
To include them in `~astropy.units.UnitBase.compose` and the results of
`~astropy.units.UnitBase.find_equivalent_units`, do::
>>> import astropy.units as u
>>> u.imperial.enable() # doctest: +SKIP
"""
from .core import UnitBase, def_unit
from . import si
_ns = globals()
###########################################################################
# LENGTH
def_unit(['inch'], 2.54 * si.cm, namespace=_ns,
doc="International inch")
def_unit(['ft', 'foot'], 12 * inch, namespace=_ns,
doc="International foot")
def_unit(['yd', 'yard'], 3 * ft, namespace=_ns,
doc="International yard")
def_unit(['mi', 'mile'], 5280 * ft, namespace=_ns,
doc="International mile")
def_unit(['mil', 'thou'], 0.001 * inch, namespace=_ns,
doc="Thousandth of an inch")
def_unit(['nmi', 'nauticalmile', 'NM'], 1852 * si.m, namespace=_ns,
doc="Nautical mile")
def_unit(['fur', 'furlong'], 660 * ft, namespace=_ns,
doc="Furlong")
###########################################################################
# AREAS
def_unit(['ac', 'acre'], 43560 * ft ** 2, namespace=_ns,
doc="International acre")
###########################################################################
# VOLUMES
def_unit(['gallon'], si.liter / 0.264172052, namespace=_ns,
doc="U.S. liquid gallon")
def_unit(['quart'], gallon / 4, namespace=_ns,
doc="U.S. liquid quart")
def_unit(['pint'], quart / 2, namespace=_ns,
doc="U.S. liquid pint")
def_unit(['cup'], pint / 2, namespace=_ns,
doc="U.S. customary cup")
def_unit(['foz', 'fluid_oz', 'fluid_ounce'], cup / 8, namespace=_ns,
doc="U.S. fluid ounce")
def_unit(['tbsp', 'tablespoon'], foz / 2, namespace=_ns,
doc="U.S. customary tablespoon")
def_unit(['tsp', 'teaspoon'], tbsp / 3, namespace=_ns,
doc="U.S. customary teaspoon")
###########################################################################
# MASS
def_unit(['oz', 'ounce'], 28.349523125 * si.g, namespace=_ns,
doc="International avoirdupois ounce: mass")
def_unit(['lb', 'lbm', 'pound'], 16 * oz, namespace=_ns,
doc="International avoirdupois pound: mass")
def_unit(['st', 'stone'], 14 * lb, namespace=_ns,
doc="International avoirdupois stone: mass")
def_unit(['ton'], 2000 * lb, namespace=_ns,
doc="International avoirdupois ton: mass")
def_unit(['slug'], 32.174049 * lb, namespace=_ns,
doc="slug: mass")
###########################################################################
# SPEED
def_unit(['kn', 'kt', 'knot', 'NMPH'], nmi / si.h, namespace=_ns,
doc="nautical unit of speed: 1 nmi per hour")
###########################################################################
# FORCE
def_unit('lbf', slug * ft * si.s**-2, namespace=_ns,
doc="Pound: force")
def_unit(['kip', 'kilopound'], 1000 * lbf, namespace=_ns,
doc="Kilopound: force")
##########################################################################
# ENERGY
def_unit(['BTU', 'btu'], 1.05505585 * si.kJ, namespace=_ns,
doc="British thermal unit")
def_unit(['cal', 'calorie'], 4.184 * si.J, namespace=_ns,
doc="Thermochemical calorie: pre-SI metric unit of energy")
def_unit(['kcal', 'Cal', 'Calorie', 'kilocal', 'kilocalorie'],
1000 * cal, namespace=_ns,
doc="Calorie: colloquial definition of Calorie")
##########################################################################
# PRESSURE
def_unit('psi', lbf * inch ** -2, namespace=_ns,
doc="Pound per square inch: pressure")
###########################################################################
# POWER
# Imperial units
def_unit(['hp', 'horsepower'], si.W / 0.00134102209, namespace=_ns,
doc="Electrical horsepower")
###########################################################################
# TEMPERATURE
def_unit(['deg_F', 'Fahrenheit'], namespace=_ns, doc='Degrees Fahrenheit',
format={'latex': r'{}^{\circ}F', 'unicode': '°F'})
###########################################################################
# CLEANUP
del UnitBase
del def_unit
###########################################################################
# DOCSTRING
# This generates a docstring for this module that describes all of the
# standard units defined here.
from .utils import generate_unit_summary as _generate_unit_summary
if __doc__ is not None:
__doc__ += _generate_unit_summary(globals())
def enable():
"""
Enable Imperial units so they appear in results of
`~astropy.units.UnitBase.find_equivalent_units` and
`~astropy.units.UnitBase.compose`.
This may be used with the ``with`` statement to enable Imperial
units only temporarily.
"""
# Local import to avoid cyclical import
from .core import add_enabled_units
# Local import to avoid polluting namespace
import inspect
return add_enabled_units(inspect.getmodule(enable))
|
ab0750b6b603468d21f9302ee9d542964a9b329a68985b6d9c9889cdf04fd830 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This package defines units used in the CDS format, both the units
defined in `Centre de Données astronomiques de Strasbourg
<http://cds.u-strasbg.fr/>`_ `Standards for Astronomical Catalogues 2.0
<http://cds.u-strasbg.fr/doc/catstd-3.2.htx>`_ format and the `complete
set of supported units <http://vizier.u-strasbg.fr/cgi-bin/Unit>`_.
This format is used by VOTable up to version 1.2.
These units are not available in the top-level `astropy.units`
namespace. To use these units, you must import the `astropy.units.cds`
module::
>>> from astropy.units import cds
>>> q = 10. * cds.lyr # doctest: +SKIP
To include them in `~astropy.units.UnitBase.compose` and the results of
`~astropy.units.UnitBase.find_equivalent_units`, do::
>>> from astropy.units import cds
>>> cds.enable() # doctest: +SKIP
"""
_ns = globals()
def _initialize_module():
# Local imports to avoid polluting top-level namespace
import numpy as np
from . import core
from .. import units as u
from ..constants import si as _si
# The CDS format also supports power-of-2 prefixes as defined here:
# http://physics.nist.gov/cuu/Units/binary.html
prefixes = core.si_prefixes + core.binary_prefixes
# CDS only uses the short prefixes
prefixes = [(short, short, factor) for (short, long, factor) in prefixes]
# The following units are defined in alphabetical order, directly from
# here: http://vizier.u-strasbg.fr/cgi-bin/Unit
mapping = [
(['A'], u.A, "Ampere"),
(['a'], u.a, "year", ['P']),
(['a0'], _si.a0, "Bohr radius"),
(['al'], u.lyr, "Light year", ['c', 'd']),
(['lyr'], u.lyr, "Light year"),
(['alpha'], _si.alpha, "Fine structure constant"),
((['AA', 'Å'], ['Angstrom', 'Angstroem']), u.AA, "Angstrom"),
(['arcm', 'arcmin'], u.arcminute, "minute of arc"),
(['arcs', 'arcsec'], u.arcsecond, "second of arc"),
(['atm'], _si.atm, "atmosphere"),
(['AU', 'au'], u.au, "astronomical unit"),
(['bar'], u.bar, "bar"),
(['barn'], u.barn, "barn"),
(['bit'], u.bit, "bit"),
(['byte'], u.byte, "byte"),
(['C'], u.C, "Coulomb"),
(['c'], _si.c, "speed of light", ['p']),
(['cal'], 4.1854 * u.J, "calorie"),
(['cd'], u.cd, "candela"),
(['ct'], u.ct, "count"),
(['D'], u.D, "Debye (dipole)"),
(['d'], u.d, "Julian day", ['c']),
((['deg', '°'], ['degree']), u.degree, "degree"),
(['dyn'], u.dyn, "dyne"),
(['e'], _si.e, "electron charge", ['m']),
(['eps0'], _si.eps0, "electric constant"),
(['erg'], u.erg, "erg"),
(['eV'], u.eV, "electron volt"),
(['F'], u.F, "Farad"),
(['G'], _si.G, "Gravitation constant"),
(['g'], u.g, "gram"),
(['gauss'], u.G, "Gauss"),
(['geoMass', 'Mgeo'], u.M_earth, "Earth mass"),
(['H'], u.H, "Henry"),
(['h'], u.h, "hour", ['p']),
(['hr'], u.h, "hour"),
(['\\h'], _si.h, "Planck constant"),
(['Hz'], u.Hz, "Hertz"),
(['inch'], 0.0254 * u.m, "inch"),
(['J'], u.J, "Joule"),
(['JD'], u.d, "Julian day", ['M']),
(['jovMass', 'Mjup'], u.M_jup, "Jupiter mass"),
(['Jy'], u.Jy, "Jansky"),
(['K'], u.K, "Kelvin"),
(['k'], _si.k_B, "Boltzmann"),
(['l'], u.l, "litre", ['a']),
(['lm'], u.lm, "lumen"),
(['Lsun', 'solLum'], u.solLum, "solar luminosity"),
(['lx'], u.lx, "lux"),
(['m'], u.m, "meter"),
(['mag'], u.mag, "magnitude"),
(['me'], _si.m_e, "electron mass"),
(['min'], u.minute, "minute"),
(['MJD'], u.d, "Julian day"),
(['mmHg'], 133.322387415 * u.Pa, "millimeter of mercury"),
(['mol'], u.mol, "mole"),
(['mp'], _si.m_p, "proton mass"),
(['Msun', 'solMass'], u.solMass, "solar mass"),
((['mu0', 'µ0'], []), _si.mu0, "magnetic constant"),
(['muB'], _si.muB, "Bohr magneton"),
(['N'], u.N, "Newton"),
(['Ohm'], u.Ohm, "Ohm"),
(['Pa'], u.Pa, "Pascal"),
(['pc'], u.pc, "parsec"),
(['ph'], u.ph, "photon"),
(['pi'], u.Unit(np.pi), "π"),
(['pix'], u.pix, "pixel"),
(['ppm'], u.Unit(1e-6), "parts per million"),
(['R'], _si.R, "gas constant"),
(['rad'], u.radian, "radian"),
(['Rgeo'], _si.R_earth, "Earth equatorial radius"),
(['Rjup'], _si.R_jup, "Jupiter equatorial radius"),
(['Rsun', 'solRad'], u.solRad, "solar radius"),
(['Ry'], u.Ry, "Rydberg"),
(['S'], u.S, "Siemens"),
(['s', 'sec'], u.s, "second"),
(['sr'], u.sr, "steradian"),
(['Sun'], u.Sun, "solar unit"),
(['T'], u.T, "Tesla"),
(['t'], 1e3 * u.kg, "metric tonne", ['c']),
(['u'], _si.u, "atomic mass", ['da', 'a']),
(['V'], u.V, "Volt"),
(['W'], u.W, "Watt"),
(['Wb'], u.Wb, "Weber"),
(['yr'], u.a, "year"),
]
for entry in mapping:
if len(entry) == 3:
names, unit, doc = entry
excludes = []
else:
names, unit, doc, excludes = entry
core.def_unit(names, unit, prefixes=prefixes, namespace=_ns, doc=doc,
exclude_prefixes=excludes)
core.def_unit(['µas'], u.microarcsecond,
doc="microsecond of arc", namespace=_ns)
core.def_unit(['mas'], u.milliarcsecond,
doc="millisecond of arc", namespace=_ns)
core.def_unit(['---'], u.dimensionless_unscaled,
doc="dimensionless and unscaled", namespace=_ns)
core.def_unit(['%'], u.percent,
doc="percent", namespace=_ns)
# The Vizier "standard" defines this in units of "kg s-3", but
# that may not make a whole lot of sense, so here we just define
# it as its own new disconnected unit.
core.def_unit(['Crab'], prefixes=prefixes, namespace=_ns,
doc="Crab (X-ray) flux")
_initialize_module()
###########################################################################
# DOCSTRING
# This generates a docstring for this module that describes all of the
# standard units defined here.
from .utils import generate_unit_summary as _generate_unit_summary
if __doc__ is not None:
__doc__ += _generate_unit_summary(globals())
def enable():
"""
Enable CDS units so they appear in results of
`~astropy.units.UnitBase.find_equivalent_units` and
`~astropy.units.UnitBase.compose`. This will disable
all of the "default" `astropy.units` units, since there
are some namespace clashes between the two.
This may be used with the ``with`` statement to enable CDS
units only temporarily.
"""
# Local import to avoid cyclical import
from .core import set_enabled_units
# Local import to avoid polluting namespace
import inspect
return set_enabled_units(inspect.getmodule(enable))
|
6bc080b4767391365d78381917a9a9977a5de63909c656fa7686af3c90a53581 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
# The idea for this module (but no code) was borrowed from the
# quantities (http://pythonhosted.org/quantities/) package.
"""Helper functions for Quantity.
In particular, this implements the logic that determines scaling and result
units for a given ufunc, given input units.
"""
from fractions import Fraction
import numpy as np
from .core import (UnitsError, UnitConversionError, UnitTypeError,
dimensionless_unscaled, get_current_unit_registry)
def _d(unit):
if unit is None:
return dimensionless_unscaled
else:
return unit
def get_converter(from_unit, to_unit):
"""Like Unit._get_converter, except returns None if no scaling is needed,
i.e., if the inferred scale is unity."""
try:
scale = from_unit._to(to_unit)
except UnitsError:
return from_unit._apply_equivalencies(
from_unit, to_unit, get_current_unit_registry().equivalencies)
except AttributeError:
raise UnitTypeError("Unit '{0}' cannot be converted to '{1}'"
.format(from_unit, to_unit))
if scale == 1.:
return None
else:
return lambda val: scale * val
def get_converters_and_unit(f, unit1, unit2):
converters = [None, None]
# By default, we try adjusting unit2 to unit1, so that the result will
# be unit1 as well. But if there is no second unit, we have to try
# adjusting unit1 (to dimensionless, see below).
if unit2 is None:
if unit1 is None:
# No units for any input -- e.g., np.add(a1, a2, out=q)
return converters, dimensionless_unscaled
changeable = 0
# swap units.
unit2 = unit1
unit1 = None
elif unit2 is unit1:
# ensure identical units is fast ("==" is slow, so avoid that).
return converters, unit1
else:
changeable = 1
# Try to get a converter from unit2 to unit1.
if unit1 is None:
try:
converters[changeable] = get_converter(unit2,
dimensionless_unscaled)
except UnitsError:
# special case: would be OK if unitless number is zero, inf, nan
converters[1-changeable] = False
return converters, unit2
else:
return converters, dimensionless_unscaled
else:
try:
converters[changeable] = get_converter(unit2, unit1)
except UnitsError:
raise UnitConversionError(
"Can only apply '{0}' function to quantities "
"with compatible dimensions"
.format(f.__name__))
return converters, unit1
def can_have_arbitrary_unit(value):
"""Test whether the items in value can have arbitrary units
Numbers whose value does not change upon a unit change, i.e.,
zero, infinity, or not-a-number
Parameters
----------
value : number or array
Returns
-------
`True` if each member is either zero or not finite, `False` otherwise
"""
return np.all(np.logical_or(np.equal(value, 0.), ~np.isfinite(value)))
# SINGLE ARGUMENT UFUNC HELPERS
#
# The functions below take a single argument, which is the quantity upon which
# the ufunc is being used. The output of the helper function should be two
# values: a list with a single converter to be used to scale the input before
# it is being passed to the ufunc (or None if no conversion is needed), and
# the unit the output will be in.
def helper_onearg_test(f, unit):
return ([None], None)
def helper_invariant(f, unit):
return ([None], _d(unit))
def helper_sqrt(f, unit):
return ([None], unit ** Fraction(1, 2) if unit is not None
else dimensionless_unscaled)
def helper_square(f, unit):
return ([None], unit ** 2 if unit is not None else dimensionless_unscaled)
def helper_reciprocal(f, unit):
return ([None], unit ** -1 if unit is not None else dimensionless_unscaled)
def helper_cbrt(f, unit):
return ([None], (unit ** Fraction(1, 3) if unit is not None
else dimensionless_unscaled))
def helper_modf(f, unit):
if unit is None:
return [None], (dimensionless_unscaled, dimensionless_unscaled)
try:
return ([get_converter(unit, dimensionless_unscaled)],
(dimensionless_unscaled, dimensionless_unscaled))
except UnitsError:
raise UnitTypeError("Can only apply '{0}' function to "
"dimensionless quantities"
.format(f.__name__))
def helper__ones_like(f, unit):
return [None], dimensionless_unscaled
def helper_dimensionless_to_dimensionless(f, unit):
if unit is None:
return [None], dimensionless_unscaled
try:
return ([get_converter(unit, dimensionless_unscaled)],
dimensionless_unscaled)
except UnitsError:
raise UnitTypeError("Can only apply '{0}' function to "
"dimensionless quantities"
.format(f.__name__))
def helper_dimensionless_to_radian(f, unit):
from .si import radian
if unit is None:
return [None], radian
try:
return [get_converter(unit, dimensionless_unscaled)], radian
except UnitsError:
raise UnitTypeError("Can only apply '{0}' function to "
"dimensionless quantities"
.format(f.__name__))
def helper_degree_to_radian(f, unit):
from .si import degree, radian
try:
return [get_converter(unit, degree)], radian
except UnitsError:
raise UnitTypeError("Can only apply '{0}' function to "
"quantities with angle units"
.format(f.__name__))
def helper_radian_to_degree(f, unit):
from .si import degree, radian
try:
return [get_converter(unit, radian)], degree
except UnitsError:
raise UnitTypeError("Can only apply '{0}' function to "
"quantities with angle units"
.format(f.__name__))
def helper_radian_to_dimensionless(f, unit):
from .si import radian
try:
return [get_converter(unit, radian)], dimensionless_unscaled
except UnitsError:
raise UnitTypeError("Can only apply '{0}' function to "
"quantities with angle units"
.format(f.__name__))
def helper_frexp(f, unit):
if not unit.is_unity():
raise UnitTypeError("Can only apply '{0}' function to "
"unscaled dimensionless quantities"
.format(f.__name__))
return [None], (None, None)
# TWO ARGUMENT UFUNC HELPERS
#
# The functions below take a two arguments. The output of the helper function
# should be two values: a tuple of two converters to be used to scale the
# inputs before being passed to the ufunc (None if no conversion is needed),
# and the unit the output will be in.
def helper_multiplication(f, unit1, unit2):
return [None, None], _d(unit1) * _d(unit2)
def helper_division(f, unit1, unit2):
return [None, None], _d(unit1) / _d(unit2)
def helper_power(f, unit1, unit2):
# TODO: find a better way to do this, currently need to signal that one
# still needs to raise power of unit1 in main code
if unit2 is None:
return [None, None], False
try:
return [None, get_converter(unit2, dimensionless_unscaled)], False
except UnitsError:
raise UnitTypeError("Can only raise something to a "
"dimensionless quantity")
def helper_ldexp(f, unit1, unit2):
if unit2 is not None:
raise TypeError("Cannot use ldexp with a quantity "
"as second argument.")
else:
return [None, None], _d(unit1)
def helper_copysign(f, unit1, unit2):
# if first arg is not a quantity, just return plain array
if unit1 is None:
return [None, None], None
else:
return [None, None], unit1
def helper_heaviside(f, unit1, unit2):
try:
converter2 = (get_converter(unit2, dimensionless_unscaled)
if unit2 is not None else None)
except UnitsError:
raise UnitTypeError("Can only apply 'heaviside' function with a "
"dimensionless second argument.")
return ([None, converter2], dimensionless_unscaled)
def helper_two_arg_dimensionless(f, unit1, unit2):
try:
converter1 = (get_converter(unit1, dimensionless_unscaled)
if unit1 is not None else None)
converter2 = (get_converter(unit2, dimensionless_unscaled)
if unit2 is not None else None)
except UnitsError:
raise UnitTypeError("Can only apply '{0}' function to "
"dimensionless quantities"
.format(f.__name__))
return ([converter1, converter2], dimensionless_unscaled)
# This used to be a separate function that just called get_converters_and_unit.
# Using it directly saves a few us; keeping the clearer name.
helper_twoarg_invariant = get_converters_and_unit
def helper_twoarg_comparison(f, unit1, unit2):
converters, _ = get_converters_and_unit(f, unit1, unit2)
return converters, None
def helper_twoarg_invtrig(f, unit1, unit2):
from .si import radian
converters, _ = get_converters_and_unit(f, unit1, unit2)
return converters, radian
def helper_twoarg_floor_divide(f, unit1, unit2):
converters, _ = get_converters_and_unit(f, unit1, unit2)
return converters, dimensionless_unscaled
def helper_divmod(f, unit1, unit2):
converters, result_unit = get_converters_and_unit(f, unit1, unit2)
return converters, (dimensionless_unscaled, result_unit)
def helper_degree_to_dimensionless(f, unit):
from .si import degree
try:
return [get_converter(unit, degree)], dimensionless_unscaled
except UnitsError:
raise UnitTypeError("Can only apply '{0}' function to "
"quantities with angle units"
.format(f.__name__))
def helper_degree_minute_second_to_radian(f, unit1, unit2, unit3):
from .si import degree, arcmin, arcsec, radian
try:
return [get_converter(unit1, degree),
get_converter(unit2, arcmin),
get_converter(unit3, arcsec)], radian
except UnitsError:
raise UnitTypeError("Can only apply '{0}' function to "
"quantities with angle units"
.format(f.__name__))
# list of ufuncs:
# http://docs.scipy.org/doc/numpy/reference/ufuncs.html#available-ufuncs
UFUNC_HELPERS = {}
UNSUPPORTED_UFUNCS = {
np.bitwise_and, np.bitwise_or, np.bitwise_xor, np.invert, np.left_shift,
np.right_shift, np.logical_and, np.logical_or, np.logical_xor,
np.logical_not}
for name in 'isnat', 'gcd', 'lcm':
# isnat was introduced in numpy 1.14, gcd+lcm in 1.15
ufunc = getattr(np, name, None)
if isinstance(ufunc, np.ufunc):
UNSUPPORTED_UFUNCS |= {ufunc}
# SINGLE ARGUMENT UFUNCS
# ufuncs that return a boolean and do not care about the unit
onearg_test_ufuncs = (np.isfinite, np.isinf, np.isnan, np.sign, np.signbit)
for ufunc in onearg_test_ufuncs:
UFUNC_HELPERS[ufunc] = helper_onearg_test
# ufuncs that return a value with the same unit as the input
invariant_ufuncs = (np.absolute, np.fabs, np.conj, np.conjugate, np.negative,
np.spacing, np.rint, np.floor, np.ceil, np.trunc)
for ufunc in invariant_ufuncs:
UFUNC_HELPERS[ufunc] = helper_invariant
# positive was added in numpy 1.13
if isinstance(getattr(np, 'positive', None), np.ufunc):
UFUNC_HELPERS[np.positive] = helper_invariant
# ufuncs that require dimensionless input and and give dimensionless output
dimensionless_to_dimensionless_ufuncs = (np.exp, np.expm1, np.exp2, np.log,
np.log10, np.log2, np.log1p)
for ufunc in dimensionless_to_dimensionless_ufuncs:
UFUNC_HELPERS[ufunc] = helper_dimensionless_to_dimensionless
# ufuncs that require dimensionless input and give output in radians
dimensionless_to_radian_ufuncs = (np.arccos, np.arcsin, np.arctan, np.arccosh,
np.arcsinh, np.arctanh)
for ufunc in dimensionless_to_radian_ufuncs:
UFUNC_HELPERS[ufunc] = helper_dimensionless_to_radian
# ufuncs that require input in degrees and give output in radians
degree_to_radian_ufuncs = (np.radians, np.deg2rad)
for ufunc in degree_to_radian_ufuncs:
UFUNC_HELPERS[ufunc] = helper_degree_to_radian
# ufuncs that require input in radians and give output in degrees
radian_to_degree_ufuncs = (np.degrees, np.rad2deg)
for ufunc in radian_to_degree_ufuncs:
UFUNC_HELPERS[ufunc] = helper_radian_to_degree
# ufuncs that require input in radians and give dimensionless output
radian_to_dimensionless_ufuncs = (np.cos, np.sin, np.tan, np.cosh, np.sinh,
np.tanh)
for ufunc in radian_to_dimensionless_ufuncs:
UFUNC_HELPERS[ufunc] = helper_radian_to_dimensionless
# ufuncs handled as special cases
UFUNC_HELPERS[np.sqrt] = helper_sqrt
UFUNC_HELPERS[np.square] = helper_square
UFUNC_HELPERS[np.reciprocal] = helper_reciprocal
UFUNC_HELPERS[np.cbrt] = helper_cbrt
UFUNC_HELPERS[np.core.umath._ones_like] = helper__ones_like
UFUNC_HELPERS[np.modf] = helper_modf
UFUNC_HELPERS[np.frexp] = helper_frexp
# TWO ARGUMENT UFUNCS
# two argument ufuncs that require dimensionless input and and give
# dimensionless output
two_arg_dimensionless_ufuncs = (np.logaddexp, np.logaddexp2)
for ufunc in two_arg_dimensionless_ufuncs:
UFUNC_HELPERS[ufunc] = helper_two_arg_dimensionless
# two argument ufuncs that return a value with the same unit as the input
twoarg_invariant_ufuncs = (np.add, np.subtract, np.hypot, np.maximum,
np.minimum, np.fmin, np.fmax, np.nextafter,
np.remainder, np.mod, np.fmod)
for ufunc in twoarg_invariant_ufuncs:
UFUNC_HELPERS[ufunc] = helper_twoarg_invariant
# two argument ufuncs that need compatible inputs and return a boolean
twoarg_comparison_ufuncs = (np.greater, np.greater_equal, np.less,
np.less_equal, np.not_equal, np.equal)
for ufunc in twoarg_comparison_ufuncs:
UFUNC_HELPERS[ufunc] = helper_twoarg_comparison
# two argument ufuncs that do inverse trigonometry
twoarg_invtrig_ufuncs = (np.arctan2,)
# another private function in numpy; use getattr in case it disappears
if isinstance(getattr(np.core.umath, '_arg', None), np.ufunc):
twoarg_invtrig_ufuncs += (np.core.umath._arg,)
for ufunc in twoarg_invtrig_ufuncs:
UFUNC_HELPERS[ufunc] = helper_twoarg_invtrig
# ufuncs handled as special cases
UFUNC_HELPERS[np.multiply] = helper_multiplication
UFUNC_HELPERS[np.divide] = helper_division
UFUNC_HELPERS[np.true_divide] = helper_division
UFUNC_HELPERS[np.power] = helper_power
UFUNC_HELPERS[np.ldexp] = helper_ldexp
UFUNC_HELPERS[np.copysign] = helper_copysign
UFUNC_HELPERS[np.floor_divide] = helper_twoarg_floor_divide
# heaviside only was added in numpy 1.13
if isinstance(getattr(np, 'heaviside', None), np.ufunc):
UFUNC_HELPERS[np.heaviside] = helper_heaviside
# float_power was added in numpy 1.12
if isinstance(getattr(np, 'float_power', None), np.ufunc):
UFUNC_HELPERS[np.float_power] = helper_power
# divmod only was added in numpy 1.13
if isinstance(getattr(np, 'divmod', None), np.ufunc):
UFUNC_HELPERS[np.divmod] = helper_divmod
# UFUNCS FROM SCIPY.SPECIAL
# available ufuncs in this module are at
# https://docs.scipy.org/doc/scipy/reference/special.html
try:
import scipy.special as sps
except ImportError:
pass
else:
# ufuncs that require dimensionless input and give dimensionless output
dimensionless_to_dimensionless_sps_ufuncs = (
sps.erf, sps.gamma, sps.loggamma, sps.gammasgn,
sps.psi, sps.rgamma, sps.erfc, sps.erfcx, sps.erfi, sps.wofz,
sps.dawsn, sps.entr, sps.exprel, sps.expm1, sps.log1p, sps.exp2,
sps.exp10, sps.j0, sps.j1, sps.y0, sps.y1, sps.i0, sps.i0e, sps.i1,
sps.i1e, sps.k0, sps.k0e, sps.k1, sps.k1e, sps.itj0y0,
sps.it2j0y0, sps.iti0k0, sps.it2i0k0)
for ufunc in dimensionless_to_dimensionless_sps_ufuncs:
UFUNC_HELPERS[ufunc] = helper_dimensionless_to_dimensionless
# ufuncs that require input in degrees and give dimensionless output
degree_to_dimensionless_sps_ufuncs = (
sps.cosdg, sps.sindg, sps.tandg, sps.cotdg)
for ufunc in degree_to_dimensionless_sps_ufuncs:
UFUNC_HELPERS[ufunc] = helper_degree_to_dimensionless
# ufuncs that require 2 dimensionless inputs and give dimensionless output.
# note: sps.jv and sps.jn are aliases in some scipy versions, which will
# cause the same key to be written twice, but since both are handled by the
# same helper there is no harm done.
two_arg_dimensionless_sps_ufuncs = (
sps.jv, sps.jn, sps.jve, sps.yn, sps.yv, sps.yve, sps.kn, sps.kv,
sps.kve, sps.iv, sps.ive, sps.hankel1, sps.hankel1e, sps.hankel2,
sps.hankel2e)
for ufunc in two_arg_dimensionless_sps_ufuncs:
UFUNC_HELPERS[ufunc] = helper_two_arg_dimensionless
# ufuncs handled as special cases
UFUNC_HELPERS[sps.cbrt] = helper_cbrt
UFUNC_HELPERS[sps.radian] = helper_degree_minute_second_to_radian
def converters_and_unit(function, method, *args):
"""Determine the required converters and the unit of the ufunc result.
Converters are functions required to convert to a ufunc's expected unit,
e.g., radian for np.sin; or to ensure units of two inputs are consistent,
e.g., for np.add. In these examples, the unit of the result would be
dimensionless_unscaled for np.sin, and the same consistent unit for np.add.
Parameters
----------
function : `~numpy.ufunc`
Numpy universal function
method : str
Method with which the function is evaluated, e.g.,
'__call__', 'reduce', etc.
*args : Quantity or other ndarray subclass
Input arguments to the function
Raises
------
TypeError : when the specified function cannot be used with Quantities
(e.g., np.logical_or), or when the routine does not know how to handle
the specified function (in which case an issue should be raised on
https://github.com/astropy/astropy).
UnitTypeError : when the conversion to the required (or consistent) units
is not possible.
"""
# Check whether we support this ufunc, by getting the helper function
# (defined above) which returns a list of function(s) that convert the
# input(s) to the unit required for the ufunc, as well as the unit the
# result will have (a tuple of units if there are multiple outputs).
try:
ufunc_helper = UFUNC_HELPERS[function]
except KeyError:
if function in UNSUPPORTED_UFUNCS:
raise TypeError("Cannot use function '{0}' with quantities"
.format(function.__name__))
else:
raise TypeError("Unknown ufunc {0}. Please raise issue on "
"https://github.com/astropy/astropy"
.format(function.__name__))
if method == '__call__' or (method == 'outer' and function.nin == 2):
# Find out the units of the arguments passed to the ufunc; usually,
# at least one is a quantity, but for two-argument ufuncs, the second
# could also be a Numpy array, etc. These are given unit=None.
units = [getattr(arg, 'unit', None) for arg in args]
# Determine possible conversion functions, and the result unit.
converters, result_unit = ufunc_helper(function, *units)
if any(converter is False for converter in converters):
# for two-argument ufuncs with a quantity and a non-quantity,
# the quantity normally needs to be dimensionless, *except*
# if the non-quantity can have arbitrary unit, i.e., when it
# is all zero, infinity or NaN. In that case, the non-quantity
# can just have the unit of the quantity
# (this allows, e.g., `q > 0.` independent of unit)
maybe_arbitrary_arg = args[converters.index(False)]
try:
if can_have_arbitrary_unit(maybe_arbitrary_arg):
converters = [None, None]
else:
raise UnitsError("Can only apply '{0}' function to "
"dimensionless quantities when other "
"argument is not a quantity (unless the "
"latter is all zero/infinity/nan)"
.format(function.__name__))
except TypeError:
# _can_have_arbitrary_unit failed: arg could not be compared
# with zero or checked to be finite. Then, ufunc will fail too.
raise TypeError("Unsupported operand type(s) for ufunc {0}: "
"'{1}' and '{2}'"
.format(function.__name__,
args[0].__class__.__name__,
args[1].__class__.__name__))
# In the case of np.power and np.float_power, the unit itself needs to
# be modified by an amount that depends on one of the input values,
# so we need to treat this as a special case.
# TODO: find a better way to deal with this.
if result_unit is False:
if units[0] is None or units[0] == dimensionless_unscaled:
result_unit = dimensionless_unscaled
else:
if units[1] is None:
p = args[1]
else:
p = args[1].to(dimensionless_unscaled).value
try:
result_unit = units[0] ** p
except ValueError as exc:
# Changing the unit does not work for, e.g., array-shaped
# power, but this is OK if we're (scaled) dimensionless.
try:
converters[0] = units[0]._get_converter(
dimensionless_unscaled)
except UnitConversionError:
raise exc
else:
result_unit = dimensionless_unscaled
else: # methods for which the unit should stay the same
nin = function.nin
unit = getattr(args[0], 'unit', None)
if method == 'at' and nin <= 2:
if nin == 1:
units = [unit]
else:
units = [unit, getattr(args[2], 'unit', None)]
converters, result_unit = ufunc_helper(function, *units)
# ensure there is no 'converter' for indices (2nd argument)
converters.insert(1, None)
elif method in {'reduce', 'accumulate', 'reduceat'} and nin == 2:
converters, result_unit = ufunc_helper(function, unit, unit)
converters = converters[:1]
if method == 'reduceat':
# add 'scale' for indices (2nd argument)
converters += [None]
else:
if method in {'reduce', 'accumulate',
'reduceat', 'outer'} and nin != 2:
raise ValueError("{0} only supported for binary functions"
.format(method))
raise TypeError("Unexpected ufunc method {0}. If this should "
"work, please raise an issue on"
"https://github.com/astropy/astropy"
.format(method))
# for all but __call__ method, scaling is not allowed
if unit is not None and result_unit is None:
raise TypeError("Cannot use '{1}' method on ufunc {0} with a "
"Quantity instance as the result is not a "
"Quantity.".format(function.__name__, method))
if (converters[0] is not None or
(unit is not None and unit is not result_unit and
(not result_unit.is_equivalent(unit) or
result_unit.to(unit) != 1.))):
raise UnitsError("Cannot use '{1}' method on ufunc {0} with a "
"Quantity instance as it would change the unit."
.format(function.__name__, method))
return converters, result_unit
def check_output(output, unit, inputs, function=None):
"""Check that function output can be stored in the output array given.
Parameters
----------
output : array or `~astropy.units.Quantity` or tuple
Array that should hold the function output (or tuple of such arrays).
unit : `~astropy.units.Unit` or None, or tuple
Unit that the output will have, or `None` for pure numbers (should be
tuple of same if output is a tuple of outputs).
inputs : tuple
Any input arguments. These should be castable to the output.
function : callable
The function that will be producing the output. If given, used to
give a more informative error message.
Returns
-------
arrays : `~numpy.ndarray` view of ``output`` (or tuple of such views).
Raises
------
UnitTypeError : If ``unit`` is inconsistent with the class of ``output``
TypeError : If the ``inputs`` cannot be cast safely to ``output``.
"""
if isinstance(output, tuple):
return tuple(check_output(output_, unit_, inputs, function)
for output_, unit_ in zip(output, unit))
# ``None`` indicates no actual array is needed. This can happen, e.g.,
# with np.modf(a, out=(None, b)).
if output is None:
return None
if hasattr(output, '__quantity_subclass__'):
# Check that we're not trying to store a plain Numpy array or a
# Quantity with an inconsistent unit (e.g., not angular for Angle).
if unit is None:
raise TypeError("Cannot store non-quantity output{0} in {1} "
"instance".format(
(" from {0} function".format(function.__name__)
if function is not None else ""),
type(output)))
if output.__quantity_subclass__(unit)[0] is not type(output):
raise UnitTypeError(
"Cannot store output with unit '{0}'{1} "
"in {2} instance. Use {3} instance instead."
.format(unit, (" from {0} function".format(function.__name__)
if function is not None else ""), type(output),
output.__quantity_subclass__(unit)[0]))
# Turn into ndarray, so we do not loop into array_wrap/array_ufunc
# if the output is used to store results of a function.
output = output.view(np.ndarray)
else:
# output is not a Quantity, so cannot obtain a unit.
if not (unit is None or unit is dimensionless_unscaled):
raise UnitTypeError("Cannot store quantity with dimension "
"{0}in a non-Quantity instance."
.format("" if function is None else
"resulting from {0} function "
.format(function.__name__)))
# check we can handle the dtype (e.g., that we are not int
# when float is required).
if not np.can_cast(np.result_type(*inputs), output.dtype,
casting='same_kind'):
raise TypeError("Arguments cannot be cast safely to inplace "
"output with dtype={0}".format(output.dtype))
return output
|
7a831eaa86e8cfcfc12cf3862bafcb3ae4b168950c7d61dcd365577744da5796 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Core units classes and functions
"""
import inspect
import operator
import textwrap
import warnings
import numpy as np
from ..utils.decorators import lazyproperty
from ..utils.exceptions import AstropyWarning
from ..utils.misc import isiterable, InheritDocstrings
from .utils import (is_effectively_unity, sanitize_scale, validate_power,
resolve_fractions)
from . import format as unit_format
__all__ = [
'UnitsError', 'UnitsWarning', 'UnitConversionError', 'UnitTypeError',
'UnitBase', 'NamedUnit', 'IrreducibleUnit', 'Unit', 'CompositeUnit',
'PrefixUnit', 'UnrecognizedUnit', 'def_unit', 'get_current_unit_registry',
'set_enabled_units', 'add_enabled_units',
'set_enabled_equivalencies', 'add_enabled_equivalencies',
'dimensionless_unscaled', 'one']
def _flatten_units_collection(items):
"""
Given a list of sequences, modules or dictionaries of units, or
single units, return a flat set of all the units found.
"""
if not isinstance(items, list):
items = [items]
result = set()
for item in items:
if isinstance(item, UnitBase):
result.add(item)
else:
if isinstance(item, dict):
units = item.values()
elif inspect.ismodule(item):
units = vars(item).values()
elif isiterable(item):
units = item
else:
continue
for unit in units:
if isinstance(unit, UnitBase):
result.add(unit)
return result
def _normalize_equivalencies(equivalencies):
"""
Normalizes equivalencies, ensuring each is a 4-tuple of the form::
(from_unit, to_unit, forward_func, backward_func)
Parameters
----------
equivalencies : list of equivalency pairs
Raises
------
ValueError if an equivalency cannot be interpreted
"""
if equivalencies is None:
return []
normalized = []
for i, equiv in enumerate(equivalencies):
if len(equiv) == 2:
funit, tunit = equiv
a = b = lambda x: x
elif len(equiv) == 3:
funit, tunit, a = equiv
b = a
elif len(equiv) == 4:
funit, tunit, a, b = equiv
else:
raise ValueError(
"Invalid equivalence entry {0}: {1!r}".format(i, equiv))
if not (funit is Unit(funit) and
(tunit is None or tunit is Unit(tunit)) and
callable(a) and
callable(b)):
raise ValueError(
"Invalid equivalence entry {0}: {1!r}".format(i, equiv))
normalized.append((funit, tunit, a, b))
return normalized
class _UnitRegistry:
"""
Manages a registry of the enabled units.
"""
def __init__(self, init=[], equivalencies=[]):
if isinstance(init, _UnitRegistry):
# If passed another registry we don't need to rebuild everything.
# but because these are mutable types we don't want to create
# conflicts so everything needs to be copied.
self._equivalencies = init._equivalencies.copy()
self._all_units = init._all_units.copy()
self._registry = init._registry.copy()
self._non_prefix_units = init._non_prefix_units.copy()
# The physical type is a dictionary containing sets as values.
# All of these must be copied otherwise we could alter the old
# registry.
self._by_physical_type = {k: v.copy() for k, v in
init._by_physical_type.items()}
else:
self._reset_units()
self._reset_equivalencies()
self.add_enabled_units(init)
self.add_enabled_equivalencies(equivalencies)
def _reset_units(self):
self._all_units = set()
self._non_prefix_units = set()
self._registry = {}
self._by_physical_type = {}
def _reset_equivalencies(self):
self._equivalencies = set()
@property
def registry(self):
return self._registry
@property
def all_units(self):
return self._all_units
@property
def non_prefix_units(self):
return self._non_prefix_units
def set_enabled_units(self, units):
"""
Sets the units enabled in the unit registry.
These units are searched when using
`UnitBase.find_equivalent_units`, for example.
Parameters
----------
units : list of sequences, dicts, or modules containing units, or units
This is a list of things in which units may be found
(sequences, dicts or modules), or units themselves. The
entire set will be "enabled" for searching through by
methods like `UnitBase.find_equivalent_units` and
`UnitBase.compose`.
"""
self._reset_units()
return self.add_enabled_units(units)
def add_enabled_units(self, units):
"""
Adds to the set of units enabled in the unit registry.
These units are searched when using
`UnitBase.find_equivalent_units`, for example.
Parameters
----------
units : list of sequences, dicts, or modules containing units, or units
This is a list of things in which units may be found
(sequences, dicts or modules), or units themselves. The
entire set will be added to the "enabled" set for
searching through by methods like
`UnitBase.find_equivalent_units` and `UnitBase.compose`.
"""
units = _flatten_units_collection(units)
for unit in units:
# Loop through all of the names first, to ensure all of them
# are new, then add them all as a single "transaction" below.
for st in unit._names:
if (st in self._registry and unit != self._registry[st]):
raise ValueError(
"Object with name {0!r} already exists in namespace. "
"Filter the set of units to avoid name clashes before "
"enabling them.".format(st))
for st in unit._names:
self._registry[st] = unit
self._all_units.add(unit)
if not isinstance(unit, PrefixUnit):
self._non_prefix_units.add(unit)
hash = unit._get_physical_type_id()
self._by_physical_type.setdefault(hash, set()).add(unit)
def get_units_with_physical_type(self, unit):
"""
Get all units in the registry with the same physical type as
the given unit.
Parameters
----------
unit : UnitBase instance
"""
return self._by_physical_type.get(unit._get_physical_type_id(), set())
@property
def equivalencies(self):
return list(self._equivalencies)
def set_enabled_equivalencies(self, equivalencies):
"""
Sets the equivalencies enabled in the unit registry.
These equivalencies are used if no explicit equivalencies are given,
both in unit conversion and in finding equivalent units.
This is meant in particular for allowing angles to be dimensionless.
Use with care.
Parameters
----------
equivalencies : list of equivalent pairs
E.g., as returned by
`~astropy.units.equivalencies.dimensionless_angles`.
"""
self._reset_equivalencies()
return self.add_enabled_equivalencies(equivalencies)
def add_enabled_equivalencies(self, equivalencies):
"""
Adds to the set of equivalencies enabled in the unit registry.
These equivalencies are used if no explicit equivalencies are given,
both in unit conversion and in finding equivalent units.
This is meant in particular for allowing angles to be dimensionless.
Use with care.
Parameters
----------
equivalencies : list of equivalent pairs
E.g., as returned by
`~astropy.units.equivalencies.dimensionless_angles`.
"""
# pre-normalize list to help catch mistakes
equivalencies = _normalize_equivalencies(equivalencies)
self._equivalencies |= set(equivalencies)
class _UnitContext:
def __init__(self, init=[], equivalencies=[]):
_unit_registries.append(
_UnitRegistry(init=init, equivalencies=equivalencies))
def __enter__(self):
pass
def __exit__(self, type, value, tb):
_unit_registries.pop()
_unit_registries = [_UnitRegistry()]
def get_current_unit_registry():
return _unit_registries[-1]
def set_enabled_units(units):
"""
Sets the units enabled in the unit registry.
These units are searched when using
`UnitBase.find_equivalent_units`, for example.
This may be used either permanently, or as a context manager using
the ``with`` statement (see example below).
Parameters
----------
units : list of sequences, dicts, or modules containing units, or units
This is a list of things in which units may be found
(sequences, dicts or modules), or units themselves. The
entire set will be "enabled" for searching through by methods
like `UnitBase.find_equivalent_units` and `UnitBase.compose`.
Examples
--------
>>> from astropy import units as u
>>> with u.set_enabled_units([u.pc]):
... u.m.find_equivalent_units()
...
Primary name | Unit definition | Aliases
[
pc | 3.08568e+16 m | parsec ,
]
>>> u.m.find_equivalent_units()
Primary name | Unit definition | Aliases
[
AU | 1.49598e+11 m | au, astronomical_unit ,
Angstrom | 1e-10 m | AA, angstrom ,
cm | 0.01 m | centimeter ,
earthRad | 6.3781e+06 m | R_earth, Rearth ,
jupiterRad | 7.1492e+07 m | R_jup, Rjup, R_jupiter, Rjupiter ,
lyr | 9.46073e+15 m | lightyear ,
m | irreducible | meter ,
micron | 1e-06 m | ,
pc | 3.08568e+16 m | parsec ,
solRad | 6.957e+08 m | R_sun, Rsun ,
]
"""
# get a context with a new registry, using equivalencies of the current one
context = _UnitContext(
equivalencies=get_current_unit_registry().equivalencies)
# in this new current registry, enable the units requested
get_current_unit_registry().set_enabled_units(units)
return context
def add_enabled_units(units):
"""
Adds to the set of units enabled in the unit registry.
These units are searched when using
`UnitBase.find_equivalent_units`, for example.
This may be used either permanently, or as a context manager using
the ``with`` statement (see example below).
Parameters
----------
units : list of sequences, dicts, or modules containing units, or units
This is a list of things in which units may be found
(sequences, dicts or modules), or units themselves. The
entire set will be added to the "enabled" set for searching
through by methods like `UnitBase.find_equivalent_units` and
`UnitBase.compose`.
Examples
--------
>>> from astropy import units as u
>>> from astropy.units import imperial
>>> with u.add_enabled_units(imperial):
... u.m.find_equivalent_units()
...
Primary name | Unit definition | Aliases
[
AU | 1.49598e+11 m | au, astronomical_unit ,
Angstrom | 1e-10 m | AA, angstrom ,
cm | 0.01 m | centimeter ,
earthRad | 6.3781e+06 m | R_earth, Rearth ,
ft | 0.3048 m | foot ,
fur | 201.168 m | furlong ,
inch | 0.0254 m | ,
jupiterRad | 7.1492e+07 m | R_jup, Rjup, R_jupiter, Rjupiter ,
lyr | 9.46073e+15 m | lightyear ,
m | irreducible | meter ,
mi | 1609.34 m | mile ,
micron | 1e-06 m | ,
mil | 2.54e-05 m | thou ,
nmi | 1852 m | nauticalmile, NM ,
pc | 3.08568e+16 m | parsec ,
solRad | 6.957e+08 m | R_sun, Rsun ,
yd | 0.9144 m | yard ,
]
"""
# get a context with a new registry, which is a copy of the current one
context = _UnitContext(get_current_unit_registry())
# in this new current registry, enable the further units requested
get_current_unit_registry().add_enabled_units(units)
return context
def set_enabled_equivalencies(equivalencies):
"""
Sets the equivalencies enabled in the unit registry.
These equivalencies are used if no explicit equivalencies are given,
both in unit conversion and in finding equivalent units.
This is meant in particular for allowing angles to be dimensionless.
Use with care.
Parameters
----------
equivalencies : list of equivalent pairs
E.g., as returned by
`~astropy.units.equivalencies.dimensionless_angles`.
Examples
--------
Exponentiation normally requires dimensionless quantities. To avoid
problems with complex phases::
>>> from astropy import units as u
>>> with u.set_enabled_equivalencies(u.dimensionless_angles()):
... phase = 0.5 * u.cycle
... np.exp(1j*phase) # doctest: +SKIP
<Quantity -1. +1.22464680e-16j>
"""
# doctest skipped as the complex number formatting changed in numpy 1.14.
#
# get a context with a new registry, using all units of the current one
context = _UnitContext(get_current_unit_registry())
# in this new current registry, enable the equivalencies requested
get_current_unit_registry().set_enabled_equivalencies(equivalencies)
return context
def add_enabled_equivalencies(equivalencies):
"""
Adds to the equivalencies enabled in the unit registry.
These equivalencies are used if no explicit equivalencies are given,
both in unit conversion and in finding equivalent units.
This is meant in particular for allowing angles to be dimensionless.
Since no equivalencies are enabled by default, generally it is recommended
to use `set_enabled_equivalencies`.
Parameters
----------
equivalencies : list of equivalent pairs
E.g., as returned by
`~astropy.units.equivalencies.dimensionless_angles`.
"""
# get a context with a new registry, which is a copy of the current one
context = _UnitContext(get_current_unit_registry())
# in this new current registry, enable the further equivalencies requested
get_current_unit_registry().add_enabled_equivalencies(equivalencies)
return context
class UnitsError(Exception):
"""
The base class for unit-specific exceptions.
"""
class UnitScaleError(UnitsError, ValueError):
"""
Used to catch the errors involving scaled units,
which are not recognized by FITS format.
"""
pass
class UnitConversionError(UnitsError, ValueError):
"""
Used specifically for errors related to converting between units or
interpreting units in terms of other units.
"""
class UnitTypeError(UnitsError, TypeError):
"""
Used specifically for errors in setting to units not allowed by a class.
E.g., would be raised if the unit of an `~astropy.coordinates.Angle`
instances were set to a non-angular unit.
"""
class UnitsWarning(AstropyWarning):
"""
The base class for unit-specific warnings.
"""
class UnitBase(metaclass=InheritDocstrings):
"""
Abstract base class for units.
Most of the arithmetic operations on units are defined in this
base class.
Should not be instantiated by users directly.
"""
# Make sure that __rmul__ of units gets called over the __mul__ of Numpy
# arrays to avoid element-wise multiplication.
__array_priority__ = 1000
def __deepcopy__(self, memo):
# This may look odd, but the units conversion will be very
# broken after deep-copying if we don't guarantee that a given
# physical unit corresponds to only one instance
return self
def _repr_latex_(self):
"""
Generate latex representation of unit name. This is used by
the IPython notebook to print a unit with a nice layout.
Returns
-------
Latex string
"""
return unit_format.Latex.to_string(self)
def __bytes__(self):
"""Return string representation for unit"""
return unit_format.Generic.to_string(self).encode('unicode_escape')
def __str__(self):
"""Return string representation for unit"""
return unit_format.Generic.to_string(self)
def __repr__(self):
string = unit_format.Generic.to_string(self)
return 'Unit("{0}")'.format(string)
def _get_physical_type_id(self):
"""
Returns an identifier that uniquely identifies the physical
type of this unit. It is comprised of the bases and powers of
this unit, without the scale. Since it is hashable, it is
useful as a dictionary key.
"""
unit = self.decompose()
r = zip([x.name for x in unit.bases], unit.powers)
# bases and powers are already sorted in a unique way
# r.sort()
r = tuple(r)
return r
@property
def names(self):
"""
Returns all of the names associated with this unit.
"""
raise AttributeError(
"Can not get names from unnamed units. "
"Perhaps you meant to_string()?")
@property
def name(self):
"""
Returns the canonical (short) name associated with this unit.
"""
raise AttributeError(
"Can not get names from unnamed units. "
"Perhaps you meant to_string()?")
@property
def aliases(self):
"""
Returns the alias (long) names for this unit.
"""
raise AttributeError(
"Can not get aliases from unnamed units. "
"Perhaps you meant to_string()?")
@property
def scale(self):
"""
Return the scale of the unit.
"""
return 1.0
@property
def bases(self):
"""
Return the bases of the unit.
"""
return [self]
@property
def powers(self):
"""
Return the powers of the unit.
"""
return [1]
def to_string(self, format=unit_format.Generic):
"""
Output the unit in the given format as a string.
Parameters
----------
format : `astropy.units.format.Base` instance or str
The name of a format or a formatter object. If not
provided, defaults to the generic format.
"""
f = unit_format.get_format(format)
return f.to_string(self)
def __format__(self, format_spec):
"""Try to format units using a formatter."""
try:
return self.to_string(format=format_spec)
except ValueError:
return format(str(self), format_spec)
@staticmethod
def _normalize_equivalencies(equivalencies):
"""
Normalizes equivalencies, ensuring each is a 4-tuple of the form::
(from_unit, to_unit, forward_func, backward_func)
Parameters
----------
equivalencies : list of equivalency pairs, or `None`
Returns
-------
A normalized list, including possible global defaults set by, e.g.,
`set_enabled_equivalencies`, except when `equivalencies`=`None`,
in which case the returned list is always empty.
Raises
------
ValueError if an equivalency cannot be interpreted
"""
normalized = _normalize_equivalencies(equivalencies)
if equivalencies is not None:
normalized += get_current_unit_registry().equivalencies
return normalized
def __pow__(self, p):
return CompositeUnit(1, [self], [p])
def __div__(self, m):
if isinstance(m, (bytes, str)):
m = Unit(m)
if isinstance(m, UnitBase):
if m.is_unity():
return self
return CompositeUnit(1, [self, m], [1, -1], _error_check=False)
try:
# Cannot handle this as Unit, re-try as Quantity
from .quantity import Quantity
return Quantity(1, self) / m
except TypeError:
return NotImplemented
def __rdiv__(self, m):
if isinstance(m, (bytes, str)):
return Unit(m) / self
try:
# Cannot handle this as Unit. Here, m cannot be a Quantity,
# so we make it into one, fasttracking when it does not have a
# unit, for the common case of <array> / <unit>.
from .quantity import Quantity
if hasattr(m, 'unit'):
result = Quantity(m)
result /= self
return result
else:
return Quantity(m, self**(-1))
except TypeError:
return NotImplemented
__truediv__ = __div__
__rtruediv__ = __rdiv__
def __mul__(self, m):
if isinstance(m, (bytes, str)):
m = Unit(m)
if isinstance(m, UnitBase):
if m.is_unity():
return self
elif self.is_unity():
return m
return CompositeUnit(1, [self, m], [1, 1], _error_check=False)
# Cannot handle this as Unit, re-try as Quantity.
try:
from .quantity import Quantity
return Quantity(1, self) * m
except TypeError:
return NotImplemented
def __rmul__(self, m):
if isinstance(m, (bytes, str)):
return Unit(m) * self
# Cannot handle this as Unit. Here, m cannot be a Quantity,
# so we make it into one, fasttracking when it does not have a unit
# for the common case of <array> * <unit>.
try:
from .quantity import Quantity
if hasattr(m, 'unit'):
result = Quantity(m)
result *= self
return result
else:
return Quantity(m, self)
except TypeError:
return NotImplemented
def __hash__(self):
# This must match the hash used in CompositeUnit for a unit
# with only one base and no scale or power.
return hash((str(self.scale), self.name, str('1')))
def __eq__(self, other):
if self is other:
return True
try:
other = Unit(other, parse_strict='silent')
except (ValueError, UnitsError, TypeError):
return False
# Other is Unit-like, but the test below requires it is a UnitBase
# instance; if it is not, give up (so that other can try).
if not isinstance(other, UnitBase):
return NotImplemented
try:
return is_effectively_unity(self._to(other))
except UnitsError:
return False
def __ne__(self, other):
return not (self == other)
def __le__(self, other):
scale = self._to(Unit(other))
return scale <= 1. or is_effectively_unity(scale)
def __ge__(self, other):
scale = self._to(Unit(other))
return scale >= 1. or is_effectively_unity(scale)
def __lt__(self, other):
return not (self >= other)
def __gt__(self, other):
return not (self <= other)
def __neg__(self):
return self * -1.
def is_equivalent(self, other, equivalencies=[]):
"""
Returns `True` if this unit is equivalent to ``other``.
Parameters
----------
other : unit object or string or tuple
The unit to convert to. If a tuple of units is specified, this
method returns true if the unit matches any of those in the tuple.
equivalencies : list of equivalence pairs, optional
A list of equivalence pairs to try if the units are not
directly convertible. See :ref:`unit_equivalencies`.
This list is in addition to possible global defaults set by, e.g.,
`set_enabled_equivalencies`.
Use `None` to turn off all equivalencies.
Returns
-------
bool
"""
equivalencies = self._normalize_equivalencies(equivalencies)
if isinstance(other, tuple):
return any(self.is_equivalent(u, equivalencies=equivalencies)
for u in other)
other = Unit(other, parse_strict='silent')
return self._is_equivalent(other, equivalencies)
def _is_equivalent(self, other, equivalencies=[]):
"""Returns `True` if this unit is equivalent to `other`.
See `is_equivalent`, except that a proper Unit object should be
given (i.e., no string) and that the equivalency list should be
normalized using `_normalize_equivalencies`.
"""
if isinstance(other, UnrecognizedUnit):
return False
if (self._get_physical_type_id() ==
other._get_physical_type_id()):
return True
elif len(equivalencies):
unit = self.decompose()
other = other.decompose()
for a, b, forward, backward in equivalencies:
if b is None:
# after canceling, is what's left convertible
# to dimensionless (according to the equivalency)?
try:
(other/unit).decompose([a])
return True
except Exception:
pass
else:
if(a._is_equivalent(unit) and b._is_equivalent(other) or
b._is_equivalent(unit) and a._is_equivalent(other)):
return True
return False
def _apply_equivalencies(self, unit, other, equivalencies):
"""
Internal function (used from `_get_converter`) to apply
equivalence pairs.
"""
def make_converter(scale1, func, scale2):
def convert(v):
return func(_condition_arg(v) / scale1) * scale2
return convert
for funit, tunit, a, b in equivalencies:
if tunit is None:
try:
ratio_in_funit = (other.decompose() /
unit.decompose()).decompose([funit])
return make_converter(ratio_in_funit.scale, a, 1.)
except UnitsError:
pass
else:
try:
scale1 = funit._to(unit)
scale2 = tunit._to(other)
return make_converter(scale1, a, scale2)
except UnitsError:
pass
try:
scale1 = tunit._to(unit)
scale2 = funit._to(other)
return make_converter(scale1, b, scale2)
except UnitsError:
pass
def get_err_str(unit):
unit_str = unit.to_string('unscaled')
physical_type = unit.physical_type
if physical_type != 'unknown':
unit_str = "'{0}' ({1})".format(
unit_str, physical_type)
else:
unit_str = "'{0}'".format(unit_str)
return unit_str
unit_str = get_err_str(unit)
other_str = get_err_str(other)
raise UnitConversionError(
"{0} and {1} are not convertible".format(
unit_str, other_str))
def _get_converter(self, other, equivalencies=[]):
other = Unit(other)
# First see if it is just a scaling.
try:
scale = self._to(other)
except UnitsError:
pass
else:
return lambda val: scale * _condition_arg(val)
# if that doesn't work, maybe we can do it with equivalencies?
try:
return self._apply_equivalencies(
self, other, self._normalize_equivalencies(equivalencies))
except UnitsError as exc:
# Last hope: maybe other knows how to do it?
# We assume the equivalencies have the unit itself as first item.
# TODO: maybe better for other to have a `_back_converter` method?
if hasattr(other, 'equivalencies'):
for funit, tunit, a, b in other.equivalencies:
if other is funit:
try:
return lambda v: b(self._get_converter(
tunit, equivalencies=equivalencies)(v))
except Exception:
pass
raise exc
def _to(self, other):
"""
Returns the scale to the specified unit.
See `to`, except that a Unit object should be given (i.e., no
string), and that all defaults are used, i.e., no
equivalencies and value=1.
"""
# There are many cases where we just want to ensure a Quantity is
# of a particular unit, without checking whether it's already in
# a particular unit. If we're being asked to convert from a unit
# to itself, we can short-circuit all of this.
if self is other:
return 1.0
# Don't presume decomposition is possible; e.g.,
# conversion to function units is through equivalencies.
if isinstance(other, UnitBase):
self_decomposed = self.decompose()
other_decomposed = other.decompose()
# Check quickly whether equivalent. This is faster than
# `is_equivalent`, because it doesn't generate the entire
# physical type list of both units. In other words it "fails
# fast".
if(self_decomposed.powers == other_decomposed.powers and
all(self_base is other_base for (self_base, other_base)
in zip(self_decomposed.bases, other_decomposed.bases))):
return self_decomposed.scale / other_decomposed.scale
raise UnitConversionError(
"'{0!r}' is not a scaled version of '{1!r}'".format(self, other))
def to(self, other, value=1.0, equivalencies=[]):
"""
Return the converted values in the specified unit.
Parameters
----------
other : unit object or string
The unit to convert to.
value : scalar int or float, or sequence convertible to array, optional
Value(s) in the current unit to be converted to the
specified unit. If not provided, defaults to 1.0
equivalencies : list of equivalence pairs, optional
A list of equivalence pairs to try if the units are not
directly convertible. See :ref:`unit_equivalencies`.
This list is in addition to possible global defaults set by, e.g.,
`set_enabled_equivalencies`.
Use `None` to turn off all equivalencies.
Returns
-------
values : scalar or array
Converted value(s). Input value sequences are returned as
numpy arrays.
Raises
------
UnitsError
If units are inconsistent
"""
return self._get_converter(other, equivalencies=equivalencies)(value)
def in_units(self, other, value=1.0, equivalencies=[]):
"""
Alias for `to` for backward compatibility with pynbody.
"""
return self.to(
other, value=value, equivalencies=equivalencies)
def decompose(self, bases=set()):
"""
Return a unit object composed of only irreducible units.
Parameters
----------
bases : sequence of UnitBase, optional
The bases to decompose into. When not provided,
decomposes down to any irreducible units. When provided,
the decomposed result will only contain the given units.
This will raises a `UnitsError` if it's not possible
to do so.
Returns
-------
unit : CompositeUnit object
New object containing only irreducible unit objects.
"""
raise NotImplementedError()
def _compose(self, equivalencies=[], namespace=[], max_depth=2, depth=0,
cached_results=None):
def is_final_result(unit):
# Returns True if this result contains only the expected
# units
for base in unit.bases:
if base not in namespace:
return False
return True
unit = self.decompose()
key = hash(unit)
cached = cached_results.get(key)
if cached is not None:
if isinstance(cached, Exception):
raise cached
return cached
# Prevent too many levels of recursion
# And special case for dimensionless unit
if depth >= max_depth:
cached_results[key] = [unit]
return [unit]
# Make a list including all of the equivalent units
units = [unit]
for funit, tunit, a, b in equivalencies:
if tunit is not None:
if self._is_equivalent(funit):
scale = funit.decompose().scale / unit.scale
units.append(Unit(a(1.0 / scale) * tunit).decompose())
elif self._is_equivalent(tunit):
scale = tunit.decompose().scale / unit.scale
units.append(Unit(b(1.0 / scale) * funit).decompose())
else:
if self._is_equivalent(funit):
units.append(Unit(unit.scale))
# Store partial results
partial_results = []
# Store final results that reduce to a single unit or pair of
# units
if len(unit.bases) == 0:
final_results = [set([unit]), set()]
else:
final_results = [set(), set()]
for tunit in namespace:
tunit_decomposed = tunit.decompose()
for u in units:
# If the unit is a base unit, look for an exact match
# to one of the bases of the target unit. If found,
# factor by the same power as the target unit's base.
# This allows us to factor out fractional powers
# without needing to do an exhaustive search.
if len(tunit_decomposed.bases) == 1:
for base, power in zip(u.bases, u.powers):
if tunit_decomposed._is_equivalent(base):
tunit = tunit ** power
tunit_decomposed = tunit_decomposed ** power
break
composed = (u / tunit_decomposed).decompose()
factored = composed * tunit
len_bases = len(composed.bases)
if is_final_result(factored) and len_bases <= 1:
final_results[len_bases].add(factored)
else:
partial_results.append(
(len_bases, composed, tunit))
# Do we have any minimal results?
for final_result in final_results:
if len(final_result):
results = final_results[0].union(final_results[1])
cached_results[key] = results
return results
partial_results.sort(key=operator.itemgetter(0))
# ...we have to recurse and try to further compose
results = []
for len_bases, composed, tunit in partial_results:
try:
composed_list = composed._compose(
equivalencies=equivalencies,
namespace=namespace,
max_depth=max_depth, depth=depth + 1,
cached_results=cached_results)
except UnitsError:
composed_list = []
for subcomposed in composed_list:
results.append(
(len(subcomposed.bases), subcomposed, tunit))
if len(results):
results.sort(key=operator.itemgetter(0))
min_length = results[0][0]
subresults = set()
for len_bases, composed, tunit in results:
if len_bases > min_length:
break
else:
factored = composed * tunit
if is_final_result(factored):
subresults.add(factored)
if len(subresults):
cached_results[key] = subresults
return subresults
if not is_final_result(self):
result = UnitsError(
"Cannot represent unit {0} in terms of the given "
"units".format(self))
cached_results[key] = result
raise result
cached_results[key] = [self]
return [self]
def compose(self, equivalencies=[], units=None, max_depth=2,
include_prefix_units=None):
"""
Return the simplest possible composite unit(s) that represent
the given unit. Since there may be multiple equally simple
compositions of the unit, a list of units is always returned.
Parameters
----------
equivalencies : list of equivalence pairs, optional
A list of equivalence pairs to also list. See
:ref:`unit_equivalencies`.
This list is in addition to possible global defaults set by, e.g.,
`set_enabled_equivalencies`.
Use `None` to turn off all equivalencies.
units : set of units to compose to, optional
If not provided, any known units may be used to compose
into. Otherwise, ``units`` is a dict, module or sequence
containing the units to compose into.
max_depth : int, optional
The maximum recursion depth to use when composing into
composite units.
include_prefix_units : bool, optional
When `True`, include prefixed units in the result.
Default is `True` if a sequence is passed in to ``units``,
`False` otherwise.
Returns
-------
units : list of `CompositeUnit`
A list of candidate compositions. These will all be
equally simple, but it may not be possible to
automatically determine which of the candidates are
better.
"""
# if units parameter is specified and is a sequence (list|tuple),
# include_prefix_units is turned on by default. Ex: units=[u.kpc]
if include_prefix_units is None:
include_prefix_units = isinstance(units, (list, tuple))
# Pre-normalize the equivalencies list
equivalencies = self._normalize_equivalencies(equivalencies)
# The namespace of units to compose into should be filtered to
# only include units with bases in common with self, otherwise
# they can't possibly provide useful results. Having too many
# destination units greatly increases the search space.
def has_bases_in_common(a, b):
if len(a.bases) == 0 and len(b.bases) == 0:
return True
for ab in a.bases:
for bb in b.bases:
if ab == bb:
return True
return False
def has_bases_in_common_with_equiv(unit, other):
if has_bases_in_common(unit, other):
return True
for funit, tunit, a, b in equivalencies:
if tunit is not None:
if unit._is_equivalent(funit):
if has_bases_in_common(tunit.decompose(), other):
return True
elif unit._is_equivalent(tunit):
if has_bases_in_common(funit.decompose(), other):
return True
else:
if unit._is_equivalent(funit):
if has_bases_in_common(dimensionless_unscaled, other):
return True
return False
def filter_units(units):
filtered_namespace = set()
for tunit in units:
if (isinstance(tunit, UnitBase) and
(include_prefix_units or
not isinstance(tunit, PrefixUnit)) and
has_bases_in_common_with_equiv(
decomposed, tunit.decompose())):
filtered_namespace.add(tunit)
return filtered_namespace
decomposed = self.decompose()
if units is None:
units = filter_units(self._get_units_with_same_physical_type(
equivalencies=equivalencies))
if len(units) == 0:
units = get_current_unit_registry().non_prefix_units
elif isinstance(units, dict):
units = set(filter_units(units.values()))
elif inspect.ismodule(units):
units = filter_units(vars(units).values())
else:
units = filter_units(_flatten_units_collection(units))
def sort_results(results):
if not len(results):
return []
# Sort the results so the simplest ones appear first.
# Simplest is defined as "the minimum sum of absolute
# powers" (i.e. the fewest bases), and preference should
# be given to results where the sum of powers is positive
# and the scale is exactly equal to 1.0
results = list(results)
results.sort(key=lambda x: np.abs(x.scale))
results.sort(key=lambda x: np.sum(np.abs(x.powers)))
results.sort(key=lambda x: np.sum(x.powers) < 0.0)
results.sort(key=lambda x: not is_effectively_unity(x.scale))
last_result = results[0]
filtered = [last_result]
for result in results[1:]:
if str(result) != str(last_result):
filtered.append(result)
last_result = result
return filtered
return sort_results(self._compose(
equivalencies=equivalencies, namespace=units,
max_depth=max_depth, depth=0, cached_results={}))
def to_system(self, system):
"""
Converts this unit into ones belonging to the given system.
Since more than one result may be possible, a list is always
returned.
Parameters
----------
system : module
The module that defines the unit system. Commonly used
ones include `astropy.units.si` and `astropy.units.cgs`.
To use your own module it must contain unit objects and a
sequence member named ``bases`` containing the base units of
the system.
Returns
-------
units : list of `CompositeUnit`
The list is ranked so that units containing only the base
units of that system will appear first.
"""
bases = set(system.bases)
def score(compose):
# In case that compose._bases has no elements we return
# 'np.inf' as 'score value'. It does not really matter which
# number we would return. This case occurs for instance for
# dimensionless quantities:
compose_bases = compose.bases
if len(compose_bases) == 0:
return np.inf
else:
sum = 0
for base in compose_bases:
if base in bases:
sum += 1
return sum / float(len(compose_bases))
x = self.decompose(bases=bases)
composed = x.compose(units=system)
composed = sorted(composed, key=score, reverse=True)
return composed
@lazyproperty
def si(self):
"""
Returns a copy of the current `Unit` instance in SI units.
"""
from . import si
return self.to_system(si)[0]
@lazyproperty
def cgs(self):
"""
Returns a copy of the current `Unit` instance with CGS units.
"""
from . import cgs
return self.to_system(cgs)[0]
@property
def physical_type(self):
"""
Return the physical type on the unit.
Examples
--------
>>> from astropy import units as u
>>> print(u.m.physical_type)
length
"""
from . import physical
return physical.get_physical_type(self)
def _get_units_with_same_physical_type(self, equivalencies=[]):
"""
Return a list of registered units with the same physical type
as this unit.
This function is used by Quantity to add its built-in
conversions to equivalent units.
This is a private method, since end users should be encouraged
to use the more powerful `compose` and `find_equivalent_units`
methods (which use this under the hood).
Parameters
----------
equivalencies : list of equivalence pairs, optional
A list of equivalence pairs to also pull options from.
See :ref:`unit_equivalencies`. It must already be
normalized using `_normalize_equivalencies`.
"""
unit_registry = get_current_unit_registry()
units = set(unit_registry.get_units_with_physical_type(self))
for funit, tunit, a, b in equivalencies:
if tunit is not None:
if self.is_equivalent(funit) and tunit not in units:
units.update(
unit_registry.get_units_with_physical_type(tunit))
if self._is_equivalent(tunit) and funit not in units:
units.update(
unit_registry.get_units_with_physical_type(funit))
else:
if self.is_equivalent(funit):
units.add(dimensionless_unscaled)
return units
class EquivalentUnitsList(list):
"""
A class to handle pretty-printing the result of
`find_equivalent_units`.
"""
def __repr__(self):
if len(self) == 0:
return "[]"
else:
lines = []
for u in self:
irred = u.decompose().to_string()
if irred == u.name:
irred = "irreducible"
lines.append((u.name, irred, ', '.join(u.aliases)))
lines.sort()
lines.insert(0, ('Primary name', 'Unit definition', 'Aliases'))
widths = [0, 0, 0]
for line in lines:
for i, col in enumerate(line):
widths[i] = max(widths[i], len(col))
f = " {{0:<{0}s}} | {{1:<{1}s}} | {{2:<{2}s}}".format(*widths)
lines = [f.format(*line) for line in lines]
lines = (lines[0:1] +
['['] +
['{0} ,'.format(x) for x in lines[1:]] +
[']'])
return '\n'.join(lines)
def find_equivalent_units(self, equivalencies=[], units=None,
include_prefix_units=False):
"""
Return a list of all the units that are the same type as ``self``.
Parameters
----------
equivalencies : list of equivalence pairs, optional
A list of equivalence pairs to also list. See
:ref:`unit_equivalencies`.
Any list given, including an empty one, supercedes global defaults
that may be in effect (as set by `set_enabled_equivalencies`)
units : set of units to search in, optional
If not provided, all defined units will be searched for
equivalencies. Otherwise, may be a dict, module or
sequence containing the units to search for equivalencies.
include_prefix_units : bool, optional
When `True`, include prefixed units in the result.
Default is `False`.
Returns
-------
units : list of `UnitBase`
A list of unit objects that match ``u``. A subclass of
`list` (``EquivalentUnitsList``) is returned that
pretty-prints the list of units when output.
"""
results = self.compose(
equivalencies=equivalencies, units=units, max_depth=1,
include_prefix_units=include_prefix_units)
results = set(
x.bases[0] for x in results if len(x.bases) == 1)
return self.EquivalentUnitsList(results)
def is_unity(self):
"""
Returns `True` if the unit is unscaled and dimensionless.
"""
return False
class NamedUnit(UnitBase):
"""
The base class of units that have a name.
Parameters
----------
st : str, list of str, 2-tuple
The name of the unit. If a list of strings, the first element
is the canonical (short) name, and the rest of the elements
are aliases. If a tuple of lists, the first element is a list
of short names, and the second element is a list of long
names; all but the first short name are considered "aliases".
Each name *should* be a valid Python identifier to make it
easy to access, but this is not required.
namespace : dict, optional
When provided, inject the unit, and all of its aliases, in the
given namespace dictionary. If a unit by the same name is
already in the namespace, a ValueError is raised.
doc : str, optional
A docstring describing the unit.
format : dict, optional
A mapping to format-specific representations of this unit.
For example, for the ``Ohm`` unit, it might be nice to have it
displayed as ``\\Omega`` by the ``latex`` formatter. In that
case, `format` argument should be set to::
{'latex': r'\\Omega'}
Raises
------
ValueError
If any of the given unit names are already in the registry.
ValueError
If any of the given unit names are not valid Python tokens.
"""
def __init__(self, st, doc=None, format=None, namespace=None):
UnitBase.__init__(self)
if isinstance(st, (bytes, str)):
self._names = [st]
self._short_names = [st]
self._long_names = []
elif isinstance(st, tuple):
if not len(st) == 2:
raise ValueError("st must be string, list or 2-tuple")
self._names = st[0] + [n for n in st[1] if n not in st[0]]
if not len(self._names):
raise ValueError("must provide at least one name")
self._short_names = st[0][:]
self._long_names = st[1][:]
else:
if len(st) == 0:
raise ValueError(
"st list must have at least one entry")
self._names = st[:]
self._short_names = [st[0]]
self._long_names = st[1:]
if format is None:
format = {}
self._format = format
if doc is None:
doc = self._generate_doc()
else:
doc = textwrap.dedent(doc)
doc = textwrap.fill(doc)
self.__doc__ = doc
self._inject(namespace)
def _generate_doc(self):
"""
Generate a docstring for the unit if the user didn't supply
one. This is only used from the constructor and may be
overridden in subclasses.
"""
names = self.names
if len(self.names) > 1:
return "{1} ({0})".format(*names[:2])
else:
return names[0]
def get_format_name(self, format):
"""
Get a name for this unit that is specific to a particular
format.
Uses the dictionary passed into the `format` kwarg in the
constructor.
Parameters
----------
format : str
The name of the format
Returns
-------
name : str
The name of the unit for the given format.
"""
return self._format.get(format, self.name)
@property
def names(self):
"""
Returns all of the names associated with this unit.
"""
return self._names
@property
def name(self):
"""
Returns the canonical (short) name associated with this unit.
"""
return self._names[0]
@property
def aliases(self):
"""
Returns the alias (long) names for this unit.
"""
return self._names[1:]
@property
def short_names(self):
"""
Returns all of the short names associated with this unit.
"""
return self._short_names
@property
def long_names(self):
"""
Returns all of the long names associated with this unit.
"""
return self._long_names
def _inject(self, namespace=None):
"""
Injects the unit, and all of its aliases, in the given
namespace dictionary.
"""
if namespace is None:
return
# Loop through all of the names first, to ensure all of them
# are new, then add them all as a single "transaction" below.
for name in self._names:
if name in namespace and self != namespace[name]:
raise ValueError(
"Object with name {0!r} already exists in "
"given namespace ({1!r}).".format(
name, namespace[name]))
for name in self._names:
namespace[name] = self
def _recreate_irreducible_unit(cls, names, registered):
"""
This is used to reconstruct units when passed around by
multiprocessing.
"""
registry = get_current_unit_registry().registry
if names[0] in registry:
# If in local registry return that object.
return registry[names[0]]
else:
# otherwise, recreate the unit.
unit = cls(names)
if registered:
# If not in local registry but registered in origin registry,
# enable unit in local registry.
get_current_unit_registry().add_enabled_units([unit])
return unit
class IrreducibleUnit(NamedUnit):
"""
Irreducible units are the units that all other units are defined
in terms of.
Examples are meters, seconds, kilograms, amperes, etc. There is
only once instance of such a unit per type.
"""
def __reduce__(self):
# When IrreducibleUnit objects are passed to other processes
# over multiprocessing, they need to be recreated to be the
# ones already in the subprocesses' namespace, not new
# objects, or they will be considered "unconvertible".
# Therefore, we have a custom pickler/unpickler that
# understands how to recreate the Unit on the other side.
registry = get_current_unit_registry().registry
return (_recreate_irreducible_unit,
(self.__class__, list(self.names), self.name in registry),
self.__dict__)
@property
def represents(self):
"""The unit that this named unit represents.
For an irreducible unit, that is always itself.
"""
return self
def decompose(self, bases=set()):
if len(bases) and self not in bases:
for base in bases:
try:
scale = self._to(base)
except UnitsError:
pass
else:
if is_effectively_unity(scale):
return base
else:
return CompositeUnit(scale, [base], [1],
_error_check=False)
raise UnitConversionError(
"Unit {0} can not be decomposed into the requested "
"bases".format(self))
return self
class UnrecognizedUnit(IrreducibleUnit):
"""
A unit that did not parse correctly. This allows for
roundtripping it as a string, but no unit operations actually work
on it.
Parameters
----------
st : str
The name of the unit.
"""
# For UnrecognizedUnits, we want to use "standard" Python
# pickling, not the special case that is used for
# IrreducibleUnits.
__reduce__ = object.__reduce__
def __repr__(self):
return "UnrecognizedUnit({0})".format(str(self))
def __bytes__(self):
return self.name.encode('ascii', 'replace')
def __str__(self):
return self.name
def to_string(self, format=None):
return self.name
def _unrecognized_operator(self, *args, **kwargs):
raise ValueError(
"The unit {0!r} is unrecognized, so all arithmetic operations "
"with it are invalid.".format(self.name))
__pow__ = __div__ = __rdiv__ = __truediv__ = __rtruediv__ = __mul__ = \
__rmul__ = __lt__ = __gt__ = __le__ = __ge__ = __neg__ = \
_unrecognized_operator
def __eq__(self, other):
other = Unit(other, parse_strict='silent')
return isinstance(other, UnrecognizedUnit) and self.name == other.name
def __ne__(self, other):
return not (self == other)
def is_equivalent(self, other, equivalencies=None):
self._normalize_equivalencies(equivalencies)
return self == other
def _get_converter(self, other, equivalencies=None):
self._normalize_equivalencies(equivalencies)
raise ValueError(
"The unit {0!r} is unrecognized. It can not be converted "
"to other units.".format(self.name))
def get_format_name(self, format):
return self.name
def is_unity(self):
return False
class _UnitMetaClass(InheritDocstrings):
"""
This metaclass exists because the Unit constructor should
sometimes return instances that already exist. This "overrides"
the constructor before the new instance is actually created, so we
can return an existing one.
"""
def __call__(self, s, represents=None, format=None, namespace=None,
doc=None, parse_strict='raise'):
# Short-circuit if we're already a unit
if hasattr(s, '_get_physical_type_id'):
return s
# turn possible Quantity input for s or represents into a Unit
from .quantity import Quantity
if isinstance(represents, Quantity):
if is_effectively_unity(represents.value):
represents = represents.unit
else:
# cannot use _error_check=False: scale may be effectively unity
represents = CompositeUnit(represents.value *
represents.unit.scale,
bases=represents.unit.bases,
powers=represents.unit.powers)
if isinstance(s, Quantity):
if is_effectively_unity(s.value):
s = s.unit
else:
s = CompositeUnit(s.value * s.unit.scale,
bases=s.unit.bases,
powers=s.unit.powers)
# now decide what we really need to do; define derived Unit?
if isinstance(represents, UnitBase):
# This has the effect of calling the real __new__ and
# __init__ on the Unit class.
return super().__call__(
s, represents, format=format, namespace=namespace, doc=doc)
# or interpret a Quantity (now became unit), string or number?
if isinstance(s, UnitBase):
return s
elif isinstance(s, (bytes, str)):
if len(s.strip()) == 0:
# Return the NULL unit
return dimensionless_unscaled
if format is None:
format = unit_format.Generic
f = unit_format.get_format(format)
if isinstance(s, bytes):
s = s.decode('ascii')
try:
return f.parse(s)
except Exception as e:
if parse_strict == 'silent':
pass
else:
# Deliberately not issubclass here. Subclasses
# should use their name.
if f is not unit_format.Generic:
format_clause = f.name + ' '
else:
format_clause = ''
msg = ("'{0}' did not parse as {1}unit: {2}"
.format(s, format_clause, str(e)))
if parse_strict == 'raise':
raise ValueError(msg)
elif parse_strict == 'warn':
warnings.warn(msg, UnitsWarning)
else:
raise ValueError("'parse_strict' must be 'warn', "
"'raise' or 'silent'")
return UnrecognizedUnit(s)
elif isinstance(s, (int, float, np.floating, np.integer)):
return CompositeUnit(s, [], [])
elif s is None:
raise TypeError("None is not a valid Unit")
else:
raise TypeError("{0} can not be converted to a Unit".format(s))
class Unit(NamedUnit, metaclass=_UnitMetaClass):
"""
The main unit class.
There are a number of different ways to construct a Unit, but
always returns a `UnitBase` instance. If the arguments refer to
an already-existing unit, that existing unit instance is returned,
rather than a new one.
- From a string::
Unit(s, format=None, parse_strict='silent')
Construct from a string representing a (possibly compound) unit.
The optional `format` keyword argument specifies the format the
string is in, by default ``"generic"``. For a description of
the available formats, see `astropy.units.format`.
The optional ``parse_strict`` keyword controls what happens when an
unrecognized unit string is passed in. It may be one of the following:
- ``'raise'``: (default) raise a ValueError exception.
- ``'warn'``: emit a Warning, and return an
`UnrecognizedUnit` instance.
- ``'silent'``: return an `UnrecognizedUnit` instance.
- From a number::
Unit(number)
Creates a dimensionless unit.
- From a `UnitBase` instance::
Unit(unit)
Returns the given unit unchanged.
- From `None`::
Unit()
Returns the null unit.
- The last form, which creates a new `Unit` is described in detail
below.
Parameters
----------
st : str or list of str
The name of the unit. If a list, the first element is the
canonical (short) name, and the rest of the elements are
aliases.
represents : UnitBase instance
The unit that this named unit represents.
doc : str, optional
A docstring describing the unit.
format : dict, optional
A mapping to format-specific representations of this unit.
For example, for the ``Ohm`` unit, it might be nice to have it
displayed as ``\\Omega`` by the ``latex`` formatter. In that
case, `format` argument should be set to::
{'latex': r'\\Omega'}
namespace : dictionary, optional
When provided, inject the unit (and all of its aliases) into
the given namespace.
Raises
------
ValueError
If any of the given unit names are already in the registry.
ValueError
If any of the given unit names are not valid Python tokens.
"""
def __init__(self, st, represents=None, doc=None,
format=None, namespace=None):
represents = Unit(represents)
self._represents = represents
NamedUnit.__init__(self, st, namespace=namespace, doc=doc,
format=format)
@property
def represents(self):
"""The unit that this named unit represents."""
return self._represents
def decompose(self, bases=set()):
return self._represents.decompose(bases=bases)
def is_unity(self):
return self._represents.is_unity()
def __hash__(self):
return hash(self.name) + hash(self._represents)
@classmethod
def _from_physical_type_id(cls, physical_type_id):
# get string bases and powers from the ID tuple
bases = [cls(base) for base, _ in physical_type_id]
powers = [power for _, power in physical_type_id]
if len(physical_type_id) == 1 and powers[0] == 1:
unit = bases[0]
else:
unit = CompositeUnit(1, bases, powers)
return unit
class PrefixUnit(Unit):
"""
A unit that is simply a SI-prefixed version of another unit.
For example, ``mm`` is a `PrefixUnit` of ``.001 * m``.
The constructor is the same as for `Unit`.
"""
class CompositeUnit(UnitBase):
"""
Create a composite unit using expressions of previously defined
units.
Direct use of this class is not recommended. Instead use the
factory function `Unit` and arithmetic operators to compose
units.
Parameters
----------
scale : number
A scaling factor for the unit.
bases : sequence of `UnitBase`
A sequence of units this unit is composed of.
powers : sequence of numbers
A sequence of powers (in parallel with ``bases``) for each
of the base units.
"""
def __init__(self, scale, bases, powers, decompose=False,
decompose_bases=set(), _error_check=True):
# There are many cases internal to astropy.units where we
# already know that all the bases are Unit objects, and the
# powers have been validated. In those cases, we can skip the
# error checking for performance reasons. When the private
# kwarg `_error_check` is False, the error checking is turned
# off.
if _error_check:
scale = sanitize_scale(scale)
for base in bases:
if not isinstance(base, UnitBase):
raise TypeError(
"bases must be sequence of UnitBase instances")
powers = [validate_power(p) for p in powers]
self._scale = scale
self._bases = bases
self._powers = powers
self._decomposed_cache = None
self._expand_and_gather(decompose=decompose, bases=decompose_bases)
self._hash = None
def __repr__(self):
if len(self._bases):
return super().__repr__()
else:
if self._scale != 1.0:
return 'Unit(dimensionless with a scale of {0})'.format(
self._scale)
else:
return 'Unit(dimensionless)'
def __hash__(self):
if self._hash is None:
parts = ([str(self._scale)] +
[x.name for x in self._bases] +
[str(x) for x in self._powers])
self._hash = hash(tuple(parts))
return self._hash
@property
def scale(self):
"""
Return the scale of the composite unit.
"""
return self._scale
@property
def bases(self):
"""
Return the bases of the composite unit.
"""
return self._bases
@property
def powers(self):
"""
Return the powers of the composite unit.
"""
return self._powers
def _expand_and_gather(self, decompose=False, bases=set()):
def add_unit(unit, power, scale):
if unit not in bases:
for base in bases:
try:
scale *= unit._to(base) ** power
except UnitsError:
pass
else:
unit = base
break
if unit in new_parts:
a, b = resolve_fractions(new_parts[unit], power)
new_parts[unit] = a + b
else:
new_parts[unit] = power
return scale
new_parts = {}
scale = self.scale
for b, p in zip(self.bases, self.powers):
if decompose and b not in bases:
b = b.decompose(bases=bases)
if isinstance(b, CompositeUnit):
scale *= b._scale ** p
for b_sub, p_sub in zip(b._bases, b._powers):
a, b = resolve_fractions(p_sub, p)
scale = add_unit(b_sub, a * b, scale)
else:
scale = add_unit(b, p, scale)
new_parts = [x for x in new_parts.items() if x[1] != 0]
new_parts.sort(key=lambda x: (-x[1], getattr(x[0], 'name', '')))
self._bases = [x[0] for x in new_parts]
self._powers = [validate_power(x[1]) for x in new_parts]
self._scale = sanitize_scale(scale)
def __copy__(self):
"""
For compatibility with python copy module.
"""
return CompositeUnit(self._scale, self._bases[:], self._powers[:])
def decompose(self, bases=set()):
if len(bases) == 0 and self._decomposed_cache is not None:
return self._decomposed_cache
for base in self.bases:
if (not isinstance(base, IrreducibleUnit) or
(len(bases) and base not in bases)):
break
else:
if len(bases) == 0:
self._decomposed_cache = self
return self
x = CompositeUnit(self.scale, self.bases, self.powers, decompose=True,
decompose_bases=bases)
if len(bases) == 0:
self._decomposed_cache = x
return x
def is_unity(self):
unit = self.decompose()
return len(unit.bases) == 0 and unit.scale == 1.0
si_prefixes = [
(['Y'], ['yotta'], 1e24),
(['Z'], ['zetta'], 1e21),
(['E'], ['exa'], 1e18),
(['P'], ['peta'], 1e15),
(['T'], ['tera'], 1e12),
(['G'], ['giga'], 1e9),
(['M'], ['mega'], 1e6),
(['k'], ['kilo'], 1e3),
(['h'], ['hecto'], 1e2),
(['da'], ['deka', 'deca'], 1e1),
(['d'], ['deci'], 1e-1),
(['c'], ['centi'], 1e-2),
(['m'], ['milli'], 1e-3),
(['u'], ['micro'], 1e-6),
(['n'], ['nano'], 1e-9),
(['p'], ['pico'], 1e-12),
(['f'], ['femto'], 1e-15),
(['a'], ['atto'], 1e-18),
(['z'], ['zepto'], 1e-21),
(['y'], ['yocto'], 1e-24)
]
binary_prefixes = [
(['Ki'], ['kibi'], 2. ** 10),
(['Mi'], ['mebi'], 2. ** 20),
(['Gi'], ['gibi'], 2. ** 30),
(['Ti'], ['tebi'], 2. ** 40),
(['Pi'], ['pebi'], 2. ** 50),
(['Ei'], ['exbi'], 2. ** 60)
]
def _add_prefixes(u, excludes=[], namespace=None, prefixes=False):
"""
Set up all of the standard metric prefixes for a unit. This
function should not be used directly, but instead use the
`prefixes` kwarg on `def_unit`.
Parameters
----------
excludes : list of str, optional
Any prefixes to exclude from creation to avoid namespace
collisions.
namespace : dict, optional
When provided, inject the unit (and all of its aliases) into
the given namespace dictionary.
prefixes : list, optional
When provided, it is a list of prefix definitions of the form:
(short_names, long_tables, factor)
"""
if prefixes is True:
prefixes = si_prefixes
elif prefixes is False:
prefixes = []
for short, full, factor in prefixes:
names = []
format = {}
for prefix in short:
if prefix in excludes:
continue
for alias in u.short_names:
names.append(prefix + alias)
# This is a hack to use Greek mu as a prefix
# for some formatters.
if prefix == 'u':
format['latex'] = r'\mu ' + u.get_format_name('latex')
format['unicode'] = 'μ' + u.get_format_name('unicode')
for key, val in u._format.items():
format.setdefault(key, prefix + val)
for prefix in full:
if prefix in excludes:
continue
for alias in u.long_names:
names.append(prefix + alias)
if len(names):
PrefixUnit(names, CompositeUnit(factor, [u], [1],
_error_check=False),
namespace=namespace, format=format)
def def_unit(s, represents=None, doc=None, format=None, prefixes=False,
exclude_prefixes=[], namespace=None):
"""
Factory function for defining new units.
Parameters
----------
s : str or list of str
The name of the unit. If a list, the first element is the
canonical (short) name, and the rest of the elements are
aliases.
represents : UnitBase instance, optional
The unit that this named unit represents. If not provided,
a new `IrreducibleUnit` is created.
doc : str, optional
A docstring describing the unit.
format : dict, optional
A mapping to format-specific representations of this unit.
For example, for the ``Ohm`` unit, it might be nice to
have it displayed as ``\\Omega`` by the ``latex``
formatter. In that case, `format` argument should be set
to::
{'latex': r'\\Omega'}
prefixes : bool or list, optional
When `True`, generate all of the SI prefixed versions of the
unit as well. For example, for a given unit ``m``, will
generate ``mm``, ``cm``, ``km``, etc. When a list, it is a list of
prefix definitions of the form:
(short_names, long_tables, factor)
Default is `False`. This function always returns the base
unit object, even if multiple scaled versions of the unit were
created.
exclude_prefixes : list of str, optional
If any of the SI prefixes need to be excluded, they may be
listed here. For example, ``Pa`` can be interpreted either as
"petaannum" or "Pascal". Therefore, when defining the
prefixes for ``a``, ``exclude_prefixes`` should be set to
``["P"]``.
namespace : dict, optional
When provided, inject the unit (and all of its aliases and
prefixes), into the given namespace dictionary.
Returns
-------
unit : `UnitBase` object
The newly-defined unit, or a matching unit that was already
defined.
"""
if represents is not None:
result = Unit(s, represents, namespace=namespace, doc=doc,
format=format)
else:
result = IrreducibleUnit(
s, namespace=namespace, doc=doc, format=format)
if prefixes:
_add_prefixes(result, excludes=exclude_prefixes, namespace=namespace,
prefixes=prefixes)
return result
def _condition_arg(value):
"""
Validate value is acceptable for conversion purposes.
Will convert into an array if not a scalar, and can be converted
into an array
Parameters
----------
value : int or float value, or sequence of such values
Returns
-------
Scalar value or numpy array
Raises
------
ValueError
If value is not as expected
"""
if isinstance(value, (float, int, complex)):
return value
if isinstance(value, np.ndarray) and value.dtype.kind in ['i', 'f', 'c']:
return value
avalue = np.array(value)
if avalue.dtype.kind not in ['i', 'f', 'c']:
raise ValueError("Value not scalar compatible or convertible to "
"an int, float, or complex array")
return avalue
dimensionless_unscaled = CompositeUnit(1, [], [], _error_check=False)
# Abbreviation of the above, see #1980
one = dimensionless_unscaled
# Maintain error in old location for backward compatibility
# TODO: Is this still needed? Should there be a deprecation warning?
unit_format.fits.UnitScaleError = UnitScaleError
|
b9c21d05b91041941137420d546ad8e7662543c8e876163c164a1fbfe7a3b85a | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This subpackage contains classes and functions for defining and converting
between different physical units.
This code is adapted from the `pynbody
<https://github.com/pynbody/pynbody>`_ units module written by Andrew
Pontzen, who has granted the Astropy project permission to use the
code under a BSD license.
"""
from .core import *
from .quantity import *
from .decorators import *
from . import si
from . import cgs
from . import astrophys
from .function import units as function_units
from .si import *
from .astrophys import *
from .cgs import *
from .physical import *
from .function.units import *
from .equivalencies import *
from .function.core import *
from .function.logarithmic import *
from .function import magnitude_zero_points
del bases
# Enable the set of default units. This notably does *not* include
# Imperial units.
set_enabled_units([si, cgs, astrophys, function_units])
|
5150bf1925ed74c36f8610b5a7d9248655995468b75889200fcc501e93e0d314 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This package defines the astrophysics-specific units. They are also
available in the `astropy.units` namespace.
"""
from . import si
from ..constants import si as _si
from .core import (UnitBase, def_unit, si_prefixes, binary_prefixes,
set_enabled_units)
# To ensure si units of the constants can be interpreted.
set_enabled_units([si])
import numpy as _numpy
_ns = globals()
###########################################################################
# LENGTH
def_unit((['AU', 'au'], ['astronomical_unit']), _si.au, namespace=_ns, prefixes=True,
doc="astronomical unit: approximately the mean Earth--Sun "
"distance.")
def_unit(['pc', 'parsec'], _si.pc, namespace=_ns, prefixes=True,
doc="parsec: approximately 3.26 light-years.")
def_unit(['solRad', 'R_sun', 'Rsun'], _si.R_sun, namespace=_ns,
doc="Solar radius", prefixes=False,
format={'latex': r'R_{\odot}', 'unicode': 'R⊙'})
def_unit(['jupiterRad', 'R_jup', 'Rjup', 'R_jupiter', 'Rjupiter'],
_si.R_jup, namespace=_ns, prefixes=False, doc="Jupiter radius",
# LaTeX jupiter symbol requires wasysym
format={'latex': r'R_{\rm J}', 'unicode': 'R♃'})
def_unit(['earthRad', 'R_earth', 'Rearth'], _si.R_earth, namespace=_ns,
prefixes=False, doc="Earth radius",
# LaTeX earth symbol requires wasysym
format={'latex': r'R_{\oplus}', 'unicode': 'R⊕'})
def_unit(['lyr', 'lightyear'], (_si.c * si.yr).to(si.m),
namespace=_ns, prefixes=True, doc="Light year")
###########################################################################
# AREAS
def_unit(['barn', 'barn'], 10 ** -28 * si.m ** 2, namespace=_ns, prefixes=True,
doc="barn: unit of area used in HEP")
###########################################################################
# ANGULAR MEASUREMENTS
def_unit(['cycle', 'cy'], 2.0 * _numpy.pi * si.rad,
namespace=_ns, prefixes=False,
doc="cycle: angular measurement, a full turn or rotation")
###########################################################################
# MASS
def_unit(['solMass', 'M_sun', 'Msun'], _si.M_sun, namespace=_ns,
prefixes=False, doc="Solar mass",
format={'latex': r'M_{\odot}', 'unicode': 'M⊙'})
def_unit(['jupiterMass', 'M_jup', 'Mjup', 'M_jupiter', 'Mjupiter'],
_si.M_jup, namespace=_ns, prefixes=False, doc="Jupiter mass",
# LaTeX jupiter symbol requires wasysym
format={'latex': r'M_{\rm J}', 'unicode': 'M♃'})
def_unit(['earthMass', 'M_earth', 'Mearth'], _si.M_earth, namespace=_ns,
prefixes=False, doc="Earth mass",
# LaTeX earth symbol requires wasysym
format={'latex': r'M_{\oplus}', 'unicode': 'M⊕'})
def_unit(['M_p'], _si.m_p, namespace=_ns, doc="Proton mass",
format={'latex': r'M_{p}', 'unicode': 'Mₚ'})
def_unit(['M_e'], _si.m_e, namespace=_ns, doc="Electron mass",
format={'latex': r'M_{e}', 'unicode': 'Mₑ'})
# Unified atomic mass unit
def_unit(['u', 'Da', 'Dalton'], _si.u, namespace=_ns,
prefixes=True, exclude_prefixes=['a', 'da'],
doc="Unified atomic mass unit")
##########################################################################
# ENERGY
# Here, explicitly convert the planck constant to 'eV s' since the constant
# can override that to give a more precise value that takes into account
# covariances between e and h. Eventually, this may also be replaced with
# just `_si.Ryd.to(eV)`.
def_unit(['Ry', 'rydberg'],
(_si.Ryd * _si.c * _si.h.to(si.eV * si.s)).to(si.eV),
namespace=_ns, prefixes=True,
doc="Rydberg: Energy of a photon whose wavenumber is the Rydberg "
"constant",
format={'latex': r'R_{\infty}', 'unicode': 'R∞'})
###########################################################################
# ILLUMINATION
def_unit(['solLum', 'L_sun', 'Lsun'], _si.L_sun, namespace=_ns,
prefixes=False, doc="Solar luminance",
format={'latex': r'L_{\odot}', 'unicode': 'L⊙'})
###########################################################################
# SPECTRAL DENSITY
def_unit((['ph', 'photon'], ['photon']),
format={'ogip': 'photon', 'vounit': 'photon'},
namespace=_ns, prefixes=True)
def_unit(['Jy', 'Jansky', 'jansky'], 1e-26 * si.W / si.m ** 2 / si.Hz,
namespace=_ns, prefixes=True,
doc="Jansky: spectral flux density")
def_unit(['R', 'Rayleigh', 'rayleigh'],
(1e10 / (4 * _numpy.pi)) *
ph * si.m ** -2 * si.s ** -1 * si.sr ** -1,
namespace=_ns, prefixes=True,
doc="Rayleigh: photon flux")
###########################################################################
# MISCELLANEOUS
# Some of these are very FITS-specific and perhaps considered a mistake.
# Maybe they should be moved into the FITS format class?
# TODO: This is defined by the FITS standard as "relative to the sun".
# Is that mass, volume, what?
def_unit(['Sun'], namespace=_ns)
###########################################################################
# EVENTS
def_unit((['ct', 'count'], ['count']),
format={'fits': 'count', 'ogip': 'count', 'vounit': 'count'},
namespace=_ns, prefixes=True, exclude_prefixes=['p'])
def_unit((['pix', 'pixel'], ['pixel']),
format={'ogip': 'pixel', 'vounit': 'pixel'},
namespace=_ns, prefixes=True)
###########################################################################
# MISCELLANEOUS
def_unit(['chan'], namespace=_ns, prefixes=True)
def_unit(['bin'], namespace=_ns, prefixes=True)
def_unit((['vox', 'voxel'], ['voxel']),
format={'fits': 'voxel', 'ogip': 'voxel', 'vounit': 'voxel'},
namespace=_ns, prefixes=True)
def_unit((['bit', 'b'], ['bit']), namespace=_ns,
prefixes=si_prefixes + binary_prefixes)
def_unit((['byte', 'B'], ['byte']), 8 * bit, namespace=_ns,
format={'vounit': 'byte'},
prefixes=si_prefixes + binary_prefixes,
exclude_prefixes=['d'])
def_unit(['adu'], namespace=_ns, prefixes=True)
def_unit(['beam'], namespace=_ns, prefixes=True)
def_unit(['electron'], doc="Number of electrons", namespace=_ns,
format={'latex': r'e^{-}', 'unicode': 'e⁻'})
###########################################################################
# CLEANUP
del UnitBase
del def_unit
del si
###########################################################################
# DOCSTRING
# This generates a docstring for this module that describes all of the
# standard units defined here.
from .utils import generate_unit_summary as _generate_unit_summary
if __doc__ is not None:
__doc__ += _generate_unit_summary(globals())
|
b51df8024d38d6753c46210c340641005da690ad54737e6ff6aac55afaff16b0 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Defines physical unit names.
This module is not intended for use by user code directly. Instead,
the physical unit name of a `Unit` can be obtained using its `ptype`
property.
"""
from . import core
from . import si
from . import astrophys
from . import cgs
from . import imperial
__all__ = ['def_physical_type', 'get_physical_type']
_physical_unit_mapping = {}
_unit_physical_mapping = {}
def def_physical_type(unit, name):
"""
Adds a new physical unit mapping.
Parameters
----------
unit : `~astropy.units.UnitBase` instance
The unit to map from.
name : str
The physical name of the unit.
"""
r = unit._get_physical_type_id()
if r in _physical_unit_mapping:
raise ValueError(
"{0!r} ({1!r}) already defined as {2!r}".format(
r, name, _physical_unit_mapping[r]))
_physical_unit_mapping[r] = name
_unit_physical_mapping[name] = r
def get_physical_type(unit):
"""
Given a unit, returns the name of the physical quantity it
represents. If it represents an unknown physical quantity,
``"unknown"`` is returned.
Parameters
----------
unit : `~astropy.units.UnitBase` instance
The unit to lookup
Returns
-------
physical : str
The name of the physical quantity, or unknown if not
known.
"""
r = unit._get_physical_type_id()
return _physical_unit_mapping.get(r, 'unknown')
for unit, name in [
(core.Unit(1), 'dimensionless'),
(si.m, 'length'),
(si.m ** 2, 'area'),
(si.m ** 3, 'volume'),
(si.s, 'time'),
(si.rad, 'angle'),
(si.sr, 'solid angle'),
(si.m / si.s, 'speed'),
(si.m / si.s ** 2, 'acceleration'),
(si.Hz, 'frequency'),
(si.g, 'mass'),
(si.mol, 'amount of substance'),
(si.K, 'temperature'),
(si.deg_C, 'temperature'),
(imperial.deg_F, 'temperature'),
(si.N, 'force'),
(si.J, 'energy'),
(si.Pa, 'pressure'),
(si.W, 'power'),
(si.kg / si.m ** 3, 'mass density'),
(si.m ** 3 / si.kg, 'specific volume'),
(si.mol / si.m ** 3, 'molar volume'),
(si.kg * si.m / si.s, 'momentum/impulse'),
(si.kg * si.m ** 2 / si.s, 'angular momentum'),
(si.rad / si.s, 'angular speed'),
(si.rad / si.s ** 2, 'angular acceleration'),
(si.g / (si.m * si.s), 'dynamic viscosity'),
(si.m ** 2 / si.s, 'kinematic viscosity'),
(si.m ** -1, 'wavenumber'),
(si.A, 'electrical current'),
(si.C, 'electrical charge'),
(si.V, 'electrical potential'),
(si.Ohm, 'electrical resistance'),
(si.S, 'electrical conductance'),
(si.F, 'electrical capacitance'),
(si.C * si.m, 'electrical dipole moment'),
(si.A / si.m ** 2, 'electrical current density'),
(si.V / si.m, 'electrical field strength'),
(si.C / si.m ** 2, 'electrical flux density'),
(si.C / si.m ** 3, 'electrical charge density'),
(si.F / si.m, 'permittivity'),
(si.Wb, 'magnetic flux'),
(si.T, 'magnetic flux density'),
(si.A / si.m, 'magnetic field strength'),
(si.H / si.m, 'electromagnetic field strength'),
(si.H, 'inductance'),
(si.cd, 'luminous intensity'),
(si.lm, 'luminous flux'),
(si.lx, 'luminous emittence/illuminance'),
(si.W / si.sr, 'radiant intensity'),
(si.cd / si.m ** 2, 'luminance'),
(astrophys.Jy, 'spectral flux density'),
(cgs.erg / si.angstrom / si.cm ** 2 / si.s, 'spectral flux density wav'),
(astrophys.photon / si.Hz / si.cm ** 2 / si.s, 'photon flux density'),
(astrophys.photon / si.AA / si.cm ** 2 / si.s, 'photon flux density wav'),
(astrophys.R, 'photon flux'),
(astrophys.bit, 'data quantity'),
(astrophys.bit / si.s, 'bandwidth'),
(cgs.Franklin, 'electrical charge (ESU)'),
(cgs.statampere, 'electrical current (ESU)'),
(cgs.Biot, 'electrical current (EMU)'),
(cgs.abcoulomb, 'electrical charge (EMU)')
]:
def_physical_type(unit, name)
|
912cf6d1104ff23ab398a28eb3c6a74d60733e05fdd649603a6aaad7930fa3d9 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Miscellaneous utilities for `astropy.units`.
None of the functions in the module are meant for use outside of the
package.
"""
import numbers
import io
import re
from fractions import Fraction
import numpy as np
from numpy import finfo
_float_finfo = finfo(float)
# take float here to ensure comparison with another float is fast
# give a little margin since often multiple calculations happened
_JUST_BELOW_UNITY = float(1.-4.*_float_finfo.epsneg)
_JUST_ABOVE_UNITY = float(1.+4.*_float_finfo.eps)
def _get_first_sentence(s):
"""
Get the first sentence from a string and remove any carriage
returns.
"""
x = re.match(r".*?\S\.\s", s)
if x is not None:
s = x.group(0)
return s.replace('\n', ' ')
def _iter_unit_summary(namespace):
"""
Generates the ``(unit, doc, represents, aliases, prefixes)``
tuple used to format the unit summary docs in `generate_unit_summary`.
"""
from . import core
# Get all of the units, and keep track of which ones have SI
# prefixes
units = []
has_prefixes = set()
for key, val in namespace.items():
# Skip non-unit items
if not isinstance(val, core.UnitBase):
continue
# Skip aliases
if key != val.name:
continue
if isinstance(val, core.PrefixUnit):
# This will return the root unit that is scaled by the prefix
# attached to it
has_prefixes.add(val._represents.bases[0].name)
else:
units.append(val)
# Sort alphabetically, case insensitive
units.sort(key=lambda x: x.name.lower())
for unit in units:
doc = _get_first_sentence(unit.__doc__).strip()
represents = ''
if isinstance(unit, core.Unit):
represents = ":math:`{0}`".format(
unit._represents.to_string('latex')[1:-1])
aliases = ', '.join('``{0}``'.format(x) for x in unit.aliases)
yield (unit, doc, represents, aliases, 'Yes' if unit.name in has_prefixes else 'No')
def generate_unit_summary(namespace):
"""
Generates a summary of units from a given namespace. This is used
to generate the docstring for the modules that define the actual
units.
Parameters
----------
namespace : dict
A namespace containing units.
Returns
-------
docstring : str
A docstring containing a summary table of the units.
"""
docstring = io.StringIO()
docstring.write("""
.. list-table:: Available Units
:header-rows: 1
:widths: 10 20 20 20 1
* - Unit
- Description
- Represents
- Aliases
- SI Prefixes
""")
for unit_summary in _iter_unit_summary(namespace):
docstring.write("""
* - ``{0}``
- {1}
- {2}
- {3}
- {4}
""".format(*unit_summary))
return docstring.getvalue()
def generate_prefixonly_unit_summary(namespace):
"""
Generates table entries for units in a namespace that are just prefixes
without the base unit. Note that this is intended to be used *after*
`generate_unit_summary` and therefore does not include the table header.
Parameters
----------
namespace : dict
A namespace containing units that are prefixes but do *not* have the
base unit in their namespace.
Returns
-------
docstring : str
A docstring containing a summary table of the units.
"""
from . import PrefixUnit
faux_namespace = {}
for nm, unit in namespace.items():
if isinstance(unit, PrefixUnit):
base_unit = unit.represents.bases[0]
faux_namespace[base_unit.name] = base_unit
docstring = io.StringIO()
for unit_summary in _iter_unit_summary(faux_namespace):
docstring.write("""
* - Prefixes for ``{0}``
- {1} prefixes
- {2}
- {3}
- Only
""".format(*unit_summary))
return docstring.getvalue()
def is_effectively_unity(value):
# value is *almost* always real, except, e.g., for u.mag**0.5, when
# it will be complex. Use try/except to ensure normal case is fast
try:
return _JUST_BELOW_UNITY <= value <= _JUST_ABOVE_UNITY
except TypeError: # value is complex
return (_JUST_BELOW_UNITY <= value.real <= _JUST_ABOVE_UNITY and
_JUST_BELOW_UNITY <= value.imag + 1 <= _JUST_ABOVE_UNITY)
def sanitize_scale(scale):
if is_effectively_unity(scale):
return 1.0
if np.iscomplex(scale): # scale is complex
if scale == 0.0:
return 0.0
if abs(scale.real) > abs(scale.imag):
if is_effectively_unity(scale.imag/scale.real + 1):
scale = scale.real
else:
if is_effectively_unity(scale.real/scale.imag + 1):
scale = complex(0., scale.imag)
return scale
def validate_power(p, support_tuples=False):
"""Convert a power to a floating point value, an integer, or a Fraction.
If a fractional power can be represented exactly as a floating point
number, convert it to a float, to make the math much faster; otherwise,
retain it as a `fractions.Fraction` object to avoid losing precision.
Conversely, if the value is indistinguishable from a rational number with a
low-numbered denominator, convert to a Fraction object.
Parameters
----------
p : float, int, Rational, Fraction
Power to be converted
"""
if isinstance(p, (numbers.Rational, Fraction)):
denom = p.denominator
if denom == 1:
p = int(p.numerator)
# This is bit-twiddling hack to see if the integer is a
# power of two
elif (denom & (denom - 1)) == 0:
p = float(p)
else:
try:
p = float(p)
except Exception:
if not np.isscalar(p):
raise ValueError("Quantities and Units may only be raised "
"to a scalar power")
else:
raise
if (p % 1.0) == 0.0:
# Denominators of 1 can just be integers.
p = int(p)
elif (p * 8.0) % 1.0 == 0.0:
# Leave alone if the denominator is exactly 2, 4 or 8, since this
# can be perfectly represented as a float, which means subsequent
# operations are much faster.
pass
else:
# Convert floats indistinguishable from a rational to Fraction.
# Here, we do not need to test values that are divisors of a higher
# number, such as 3, since it is already addressed by 6.
for i in (10, 9, 7, 6):
scaled = p * float(i)
if((scaled + 4. * _float_finfo.eps) % 1.0 <
8. * _float_finfo.eps):
p = Fraction(int(round(scaled)), i)
break
return p
def resolve_fractions(a, b):
"""
If either input is a Fraction, convert the other to a Fraction.
This ensures that any operation involving a Fraction will use
rational arithmetic and preserve precision.
"""
a_is_fraction = isinstance(a, Fraction)
b_is_fraction = isinstance(b, Fraction)
if a_is_fraction and not b_is_fraction:
b = Fraction(b)
elif not a_is_fraction and b_is_fraction:
a = Fraction(a)
return a, b
def quantity_asanyarray(a, dtype=None):
from .quantity import Quantity
if not isinstance(a, np.ndarray) and not np.isscalar(a) and any(isinstance(x, Quantity) for x in a):
return Quantity(a, dtype=dtype)
else:
return np.asanyarray(a, dtype=dtype)
|
7b8da1ec271399651d2059db06f63125d185cab8010bd3d4fcac3ad7c0089824 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module defines the `Quantity` object, which represents a number with some
associated units. `Quantity` objects support operations like ordinary numbers,
but will deal with unit conversions internally.
"""
# Standard library
import re
import numbers
from fractions import Fraction
import warnings
import numpy as np
# AstroPy
from .core import (Unit, dimensionless_unscaled, get_current_unit_registry,
UnitBase, UnitsError, UnitTypeError)
from .utils import is_effectively_unity
from .format.latex import Latex
from ..utils.compat import NUMPY_LT_1_13, NUMPY_LT_1_14
from ..utils.compat.misc import override__dir__
from ..utils.exceptions import AstropyDeprecationWarning
from ..utils.misc import isiterable, InheritDocstrings
from ..utils.data_info import ParentDtypeInfo
from .. import config as _config
from .quantity_helper import (converters_and_unit, can_have_arbitrary_unit,
check_output)
__all__ = ["Quantity", "SpecificTypeQuantity",
"QuantityInfoBase", "QuantityInfo"]
# We don't want to run doctests in the docstrings we inherit from Numpy
__doctest_skip__ = ['Quantity.*']
_UNIT_NOT_INITIALISED = "(Unit not initialised)"
_UFUNCS_FILTER_WARNINGS = {np.arcsin, np.arccos, np.arccosh, np.arctanh}
class Conf(_config.ConfigNamespace):
"""
Configuration parameters for Quantity
"""
latex_array_threshold = _config.ConfigItem(100,
'The maximum size an array Quantity can be before its LaTeX '
'representation for IPython gets "summarized" (meaning only the first '
'and last few elements are shown with "..." between). Setting this to a '
'negative number means that the value will instead be whatever numpy '
'gets from get_printoptions.')
conf = Conf()
class QuantityIterator:
"""
Flat iterator object to iterate over Quantities
A `QuantityIterator` iterator is returned by ``q.flat`` for any Quantity
``q``. It allows iterating over the array as if it were a 1-D array,
either in a for-loop or by calling its `next` method.
Iteration is done in C-contiguous style, with the last index varying the
fastest. The iterator can also be indexed using basic slicing or
advanced indexing.
See Also
--------
Quantity.flatten : Returns a flattened copy of an array.
Notes
-----
`QuantityIterator` is inspired by `~numpy.ma.core.MaskedIterator`. It
is not exported by the `~astropy.units` module. Instead of
instantiating a `QuantityIterator` directly, use `Quantity.flat`.
"""
def __init__(self, q):
self._quantity = q
self._dataiter = q.view(np.ndarray).flat
def __iter__(self):
return self
def __getitem__(self, indx):
out = self._dataiter.__getitem__(indx)
# For single elements, ndarray.flat.__getitem__ returns scalars; these
# need a new view as a Quantity.
if isinstance(out, type(self._quantity)):
return out
else:
return self._quantity._new_view(out)
def __setitem__(self, index, value):
self._dataiter[index] = self._quantity._to_own_unit(value)
def __next__(self):
"""
Return the next value, or raise StopIteration.
"""
out = next(self._dataiter)
# ndarray.flat._dataiter returns scalars, so need a view as a Quantity.
return self._quantity._new_view(out)
next = __next__
class QuantityInfoBase(ParentDtypeInfo):
# This is on a base class rather than QuantityInfo directly, so that
# it can be used for EarthLocationInfo yet make clear that that class
# should not be considered a typical Quantity subclass by Table.
attrs_from_parent = {'dtype', 'unit'} # dtype and unit taken from parent
_supports_indexing = True
@staticmethod
def default_format(val):
return '{0.value:}'.format(val)
@staticmethod
def possible_string_format_functions(format_):
"""Iterate through possible string-derived format functions.
A string can either be a format specifier for the format built-in,
a new-style format string, or an old-style format string.
This method is overridden in order to suppress printing the unit
in each row since it is already at the top in the column header.
"""
yield lambda format_, val: format(val.value, format_)
yield lambda format_, val: format_.format(val.value)
yield lambda format_, val: format_ % val.value
class QuantityInfo(QuantityInfoBase):
"""
Container for meta information like name, description, format. This is
required when the object is used as a mixin column within a table, but can
be used as a general way to store meta information.
"""
_represent_as_dict_attrs = ('value', 'unit')
def _construct_from_dict(self, map):
# Need to pop value because different Quantity subclasses use
# different first arg name for the value. :-(
value = map.pop('value')
return self._parent_cls(value, **map)
def new_like(self, cols, length, metadata_conflicts='warn', name=None):
"""
Return a new Quantity instance which is consistent with the
input ``cols`` and has ``length`` rows.
This is intended for creating an empty column object whose elements can
be set in-place for table operations like join or vstack.
Parameters
----------
cols : list
List of input columns
length : int
Length of the output column object
metadata_conflicts : str ('warn'|'error'|'silent')
How to handle metadata conflicts
name : str
Output column name
Returns
-------
col : Quantity (or subclass)
Empty instance of this class consistent with ``cols``
"""
# Get merged info attributes like shape, dtype, format, description, etc.
attrs = self.merge_cols_attributes(cols, metadata_conflicts, name,
('meta', 'format', 'description'))
# Make an empty quantity using the unit of the last one.
shape = (length,) + attrs.pop('shape')
dtype = attrs.pop('dtype')
# Use zeros so we do not get problems for Quantity subclasses such
# as Longitude and Latitude, which cannot take arbitrary values.
data = np.zeros(shape=shape, dtype=dtype)
# Get arguments needed to reconstruct class
map = {key: (data if key == 'value' else getattr(cols[-1], key))
for key in self._represent_as_dict_attrs}
map['copy'] = False
out = self._construct_from_dict(map)
# Set remaining info attributes
for attr, value in attrs.items():
setattr(out.info, attr, value)
return out
class Quantity(np.ndarray, metaclass=InheritDocstrings):
"""A `~astropy.units.Quantity` represents a number with some associated unit.
Parameters
----------
value : number, `~numpy.ndarray`, `Quantity` object (sequence), str
The numerical value of this quantity in the units given by unit. If a
`Quantity` or sequence of them (or any other valid object with a
``unit`` attribute), creates a new `Quantity` object, converting to
`unit` units as needed. If a string, it is converted to a number or
`Quantity`, depending on whether a unit is present.
unit : `~astropy.units.UnitBase` instance, str
An object that represents the unit associated with the input value.
Must be an `~astropy.units.UnitBase` object or a string parseable by
the :mod:`~astropy.units` package.
dtype : ~numpy.dtype, optional
The dtype of the resulting Numpy array or scalar that will
hold the value. If not provided, it is determined from the input,
except that any input that cannot represent float (integer and bool)
is converted to float.
copy : bool, optional
If `True` (default), then the value is copied. Otherwise, a copy will
only be made if ``__array__`` returns a copy, if value is a nested
sequence, or if a copy is needed to satisfy an explicitly given
``dtype``. (The `False` option is intended mostly for internal use,
to speed up initialization where a copy is known to have been made.
Use with care.)
order : {'C', 'F', 'A'}, optional
Specify the order of the array. As in `~numpy.array`. This parameter
is ignored if the input is a `Quantity` and ``copy=False``.
subok : bool, optional
If `False` (default), the returned array will be forced to be a
`Quantity`. Otherwise, `Quantity` subclasses will be passed through,
or a subclass appropriate for the unit will be used (such as
`~astropy.units.Dex` for ``u.dex(u.AA)``).
ndmin : int, optional
Specifies the minimum number of dimensions that the resulting array
should have. Ones will be pre-pended to the shape as needed to meet
this requirement. This parameter is ignored if the input is a
`Quantity` and ``copy=False``.
Raises
------
TypeError
If the value provided is not a Python numeric type.
TypeError
If the unit provided is not either a :class:`~astropy.units.Unit`
object or a parseable string unit.
Notes
-----
Quantities can also be created by multiplying a number or array with a
:class:`~astropy.units.Unit`. See http://docs.astropy.org/en/latest/units/
"""
# Need to set a class-level default for _equivalencies, or
# Constants can not initialize properly
_equivalencies = []
# Default unit for initialization; can be overridden by subclasses,
# possibly to `None` to indicate there is no default unit.
_default_unit = dimensionless_unscaled
# Ensures views have an undefined unit.
_unit = None
__array_priority__ = 10000
def __new__(cls, value, unit=None, dtype=None, copy=True, order=None,
subok=False, ndmin=0):
if unit is not None:
# convert unit first, to avoid multiple string->unit conversions
unit = Unit(unit)
# if we allow subclasses, allow a class from the unit.
if subok:
qcls = getattr(unit, '_quantity_class', cls)
if issubclass(qcls, cls):
cls = qcls
# optimize speed for Quantity with no dtype given, copy=False
if isinstance(value, Quantity):
if unit is not None and unit is not value.unit:
value = value.to(unit)
# the above already makes a copy (with float dtype)
copy = False
if type(value) is not cls and not (subok and
isinstance(value, cls)):
value = value.view(cls)
if dtype is None:
if not copy:
return value
if not np.can_cast(np.float32, value.dtype):
dtype = float
return np.array(value, dtype=dtype, copy=copy, order=order,
subok=True, ndmin=ndmin)
# Maybe str, or list/tuple of Quantity? If so, this may set value_unit.
# To ensure array remains fast, we short-circuit it.
value_unit = None
if not isinstance(value, np.ndarray):
if isinstance(value, str):
# The first part of the regex string matches any integer/float;
# the second parts adds possible trailing .+-, which will break
# the float function below and ensure things like 1.2.3deg
# will not work.
pattern = (r'\s*[+-]?'
r'((\d+\.?\d*)|(\.\d+)|([nN][aA][nN])|'
r'([iI][nN][fF]([iI][nN][iI][tT][yY]){0,1}))'
r'([eE][+-]?\d+)?'
r'[.+-]?')
v = re.match(pattern, value)
unit_string = None
try:
value = float(v.group())
except Exception:
raise TypeError('Cannot parse "{0}" as a {1}. It does not '
'start with a number.'
.format(value, cls.__name__))
unit_string = v.string[v.end():].strip()
if unit_string:
value_unit = Unit(unit_string)
if unit is None:
unit = value_unit # signal no conversion needed below.
elif (isiterable(value) and len(value) > 0 and
all(isinstance(v, Quantity) for v in value)):
# Convert all quantities to the same unit.
if unit is None:
unit = value[0].unit
value = [q.to_value(unit) for q in value]
value_unit = unit # signal below that conversion has been done
if value_unit is None:
# If the value has a `unit` attribute and if not None
# (for Columns with uninitialized unit), treat it like a quantity.
value_unit = getattr(value, 'unit', None)
if value_unit is None:
# Default to dimensionless for no (initialized) unit attribute.
if unit is None:
unit = cls._default_unit
value_unit = unit # signal below that no conversion is needed
else:
try:
value_unit = Unit(value_unit)
except Exception as exc:
raise TypeError("The unit attribute {0!r} of the input could "
"not be parsed as an astropy Unit, raising "
"the following exception:\n{1}"
.format(value.unit, exc))
if unit is None:
unit = value_unit
elif unit is not value_unit:
copy = False # copy will be made in conversion at end
value = np.array(value, dtype=dtype, copy=copy, order=order,
subok=False, ndmin=ndmin)
# check that array contains numbers or long int objects
if (value.dtype.kind in 'OSU' and
not (value.dtype.kind == 'O' and
isinstance(value.item(() if value.ndim == 0 else 0),
numbers.Number))):
raise TypeError("The value must be a valid Python or "
"Numpy numeric type.")
# by default, cast any integer, boolean, etc., to float
if dtype is None and (not np.can_cast(np.float32, value.dtype)
or value.dtype.kind == 'O'):
value = value.astype(float)
value = value.view(cls)
value._set_unit(value_unit)
if unit is value_unit:
return value
else:
# here we had non-Quantity input that had a "unit" attribute
# with a unit different from the desired one. So, convert.
return value.to(unit)
def __array_finalize__(self, obj):
# If we're a new object or viewing an ndarray, nothing has to be done.
if obj is None or obj.__class__ is np.ndarray:
return
# If our unit is not set and obj has a valid one, use it.
if self._unit is None:
unit = getattr(obj, '_unit', None)
if unit is not None:
self._set_unit(unit)
# Copy info if the original had `info` defined. Because of the way the
# DataInfo works, `'info' in obj.__dict__` is False until the
# `info` attribute is accessed or set.
if 'info' in obj.__dict__:
self.info = obj.info
def __array_prepare__(self, obj, context=None):
# This method gets called by Numpy whenever a ufunc is called on the
# array. The object passed in ``obj`` is an empty version of the
# output array which we can e.g. change to an array sub-class, add
# attributes to, etc. After this is called, then the ufunc is called
# and the values in this empty array are set.
# In principle, this should not be needed any more in numpy >= 1.13,
# but it is still called in some np.linalg modules.
# If no context is set, just return the input
if context is None:
return obj
# Find out which ufunc is being used
function = context[0]
args = context[1][:function.nin]
# determine required converter functions -- to bring the unit of the
# input to that expected (e.g., radian for np.sin), or to get
# consistent units between two inputs (e.g., in np.add) --
# and the unit of the result
converters, result_unit = converters_and_unit(function, '__call__',
*args)
if function.nout > 1:
result_unit = result_unit[context[2]]
# We now prepare the output object
if self is obj:
# this happens if the output object is self, which happens
# for in-place operations such as q1 += q2
# Check that we're not trying to store a plain Numpy array or a
# Quantity with an inconsistent unit (e.g., not angular for Angle),
# and that we can handle the type (e.g., that we are not int when
# float is required).
check_output(obj, result_unit, (args + tuple(
(np.float16 if converter and converter(1.) % 1. != 0.
else np.int8)
for converter in converters)),
function=function)
result = self # no view needed since already a Quantity.
# in principle, if self is also an argument, it could be rescaled
# here, since it won't be needed anymore. But maybe not change
# inputs before the calculation even if they will get destroyed
else: # normal case: set up output as a Quantity
result = self._new_view(obj, result_unit)
# We now need to treat the case where the inputs have to be converted -
# the issue is that we can't actually convert the inputs since that
# would be changing the objects passed to the ufunc, which would not
# be expected by the user.
if any(converters):
# If self is both output and input (which happens for in-place
# operations), input will get overwritten with junk. To avoid
# that, hide it in a new object
if self is obj and any(self is arg for arg in args):
# but with two outputs it would become unhidden too soon
# [ie., np.modf(q1, q1, other)]. Bail.
if context[2] < function.nout - 1:
raise TypeError("Cannot apply multi-output {0} function "
"to quantities with in-place replacement "
"of an input by any but the last output."
.format(function.__name__))
# If self is already contiguous, we don't need to do
# an additional copy back into the original array, so
# we store it in `result._result`. Otherwise, we
# store it in `result._contiguous`. `__array_wrap__`
# knows how to handle putting either form back into
# the original array.
if self.flags['C_CONTIGUOUS']:
result = self.copy()
result._result = self
else:
result._contiguous = self.copy()
# ensure we remember the converter functions we need
result._converters = converters
if function in _UFUNCS_FILTER_WARNINGS:
# Filter out RuntimeWarning's caused by the ufunc being called on
# the unscaled quantity first (e.g., np.arcsin(15*u.pc/u.kpc))
self._catch_warnings = warnings.catch_warnings()
self._catch_warnings.__enter__()
warnings.filterwarnings('ignore',
message='invalid value encountered in',
category=RuntimeWarning)
# unit output will get (setting _unit could prematurely change input
# if obj is self, which happens for in-place operations; see above)
result._result_unit = result_unit
return result
def __array_wrap__(self, obj, context=None):
if context is None:
# Methods like .squeeze() created a new `ndarray` and then call
# __array_wrap__ to turn the array into self's subclass.
return self._new_view(obj)
else:
# with context defined, we are continuing after a ufunc evaluation.
if hasattr(obj, '_result_unit'):
result_unit = obj._result_unit
del obj._result_unit
else:
result_unit = None
# We now need to re-calculate quantities for which the input
# needed to be scaled.
if hasattr(obj, '_converters'):
converters = obj._converters
del obj._converters
if hasattr(self, '_catch_warnings'):
self._catch_warnings.__exit__()
del self._catch_warnings
# For in-place operations, input will get overwritten with
# junk. To avoid that, we hid it in a new object in
# __array_prepare__ and retrieve it here.
if hasattr(obj, '_result'):
obj = obj._result
elif hasattr(obj, '_contiguous'):
obj[()] = obj._contiguous
del obj._contiguous
# take array view to which output can be written without
# getting back here
obj_array = obj.view(np.ndarray)
# Find out which ufunc was called and with which inputs
function = context[0]
args = context[1][:function.nin]
# Set the inputs, rescaling as necessary
inputs = []
for arg, converter in zip(args, converters):
if converter:
inputs.append(converter(arg.value))
else: # with no conversion, input can be non-Quantity.
inputs.append(getattr(arg, 'value', arg))
# For output arrays that require scaling, we can reuse the
# output array to perform the scaling in place, as long as the
# array is not integral. Here, we set the obj_array to `None`
# when it cannot be used to store the scaled result.
# Use a try/except, since np.result_type can fail, which would
# break the wrapping #4770.
try:
tmp_dtype = np.result_type(*inputs)
# Catch the appropriate exceptions: TypeError or ValueError in
# case the result_type raised an Exception, i.e. inputs is list
except (TypeError, ValueError):
obj_array = None
else:
# Explicitly check if it can store the result.
if not (result_unit is None or
np.can_cast(tmp_dtype, obj_array.dtype)):
obj_array = None
# Re-compute the output using the ufunc
if context[2] == 0:
inputs.append(obj_array)
else:
inputs += [None, obj_array]
out = function(*inputs)
if obj_array is None:
if function.nout > 1:
out = out[context[2]]
obj = self._new_view(out, result_unit)
if result_unit is None: # return a plain array
return obj.view(np.ndarray)
elif obj is self: # all OK now, so set unit.
obj._set_unit(result_unit)
return obj
else:
return obj
def __array_ufunc__(self, function, method, *inputs, **kwargs):
"""Wrap numpy ufuncs, taking care of units.
Parameters
----------
function : callable
ufunc to wrap.
method : str
Ufunc method: ``__call__``, ``at``, ``reduce``, etc.
inputs : tuple
Input arrays.
kwargs : keyword arguments
As passed on, with ``out`` containing possible quantity output.
Returns
-------
result : `~astropy.units.Quantity`
Results of the ufunc, with the unit set properly.
"""
# Determine required conversion functions -- to bring the unit of the
# input to that expected (e.g., radian for np.sin), or to get
# consistent units between two inputs (e.g., in np.add) --
# and the unit of the result (or tuple of units for nout > 1).
converters, unit = converters_and_unit(function, method, *inputs)
out = kwargs.get('out', None)
# Avoid loop back by turning any Quantity output into array views.
if out is not None:
# If pre-allocated output is used, check it is suitable.
# This also returns array view, to ensure we don't loop back.
if function.nout == 1:
out = out[0]
out_array = check_output(out, unit, inputs, function=function)
# Ensure output argument remains a tuple.
kwargs['out'] = (out_array,) if function.nout == 1 else out_array
# Same for inputs, but here also convert if necessary.
arrays = [(converter(input_.value) if converter else
getattr(input_, 'value', input_))
for input_, converter in zip(inputs, converters)]
# Call our superclass's __array_ufunc__
result = super().__array_ufunc__(function, method, *arrays, **kwargs)
# If unit is None, a plain array is expected (e.g., comparisons), which
# means we're done.
# We're also done if the result was None (for method 'at') or
# NotImplemented, which can happen if other inputs/outputs override
# __array_ufunc__; hopefully, they can then deal with us.
if unit is None or result is None or result is NotImplemented:
return result
return self._result_as_quantity(result, unit, out)
def _result_as_quantity(self, result, unit, out):
"""Turn result into a quantity with the given unit.
If no output is given, it will take a view of the array as a quantity,
and set the unit. If output is given, those should be quantity views
of the result arrays, and the function will just set the unit.
Parameters
----------
result : `~numpy.ndarray` or tuple of `~numpy.ndarray`
Array(s) which need to be turned into quantity.
unit : `~astropy.units.Unit` or None
Unit for the quantities to be returned (or `None` if the result
should not be a quantity). Should be tuple if result is a tuple.
out : `~astropy.units.Quantity` or None
Possible output quantity. Should be `None` or a tuple if result
is a tuple.
Returns
-------
out : `~astropy.units.Quantity`
With units set.
"""
if isinstance(result, tuple):
if out is None:
out = (None,) * len(result)
return tuple(self._result_as_quantity(result_, unit_, out_)
for (result_, unit_, out_) in
zip(result, unit, out))
if out is None:
# View the result array as a Quantity with the proper unit.
return result if unit is None else self._new_view(result, unit)
# For given output, just set the unit. We know the unit is not None and
# the output is of the correct Quantity subclass, as it was passed
# through check_output.
out._set_unit(unit)
return out
def __quantity_subclass__(self, unit):
"""
Overridden by subclasses to change what kind of view is
created based on the output unit of an operation.
Parameters
----------
unit : UnitBase
The unit for which the appropriate class should be returned
Returns
-------
tuple :
- `Quantity` subclass
- bool: True if subclasses of the given class are ok
"""
return Quantity, True
def _new_view(self, obj=None, unit=None):
"""
Create a Quantity view of some array-like input, and set the unit
By default, return a view of ``obj`` of the same class as ``self`` and
with the same unit. Subclasses can override the type of class for a
given unit using ``__quantity_subclass__``, and can ensure properties
other than the unit are copied using ``__array_finalize__``.
If the given unit defines a ``_quantity_class`` of which ``self``
is not an instance, a view using this class is taken.
Parameters
----------
obj : ndarray or scalar, optional
The array to create a view of. If obj is a numpy or python scalar,
it will be converted to an array scalar. By default, ``self``
is converted.
unit : `UnitBase`, or anything convertible to a :class:`~astropy.units.Unit`, optional
The unit of the resulting object. It is used to select a
subclass, and explicitly assigned to the view if given.
If not given, the subclass and unit will be that of ``self``.
Returns
-------
view : Quantity subclass
"""
# Determine the unit and quantity subclass that we need for the view.
if unit is None:
unit = self.unit
quantity_subclass = self.__class__
else:
# In principle, could gain time by testing unit is self.unit
# as well, and then quantity_subclass = self.__class__, but
# Constant relies on going through `__quantity_subclass__`.
unit = Unit(unit)
quantity_subclass = getattr(unit, '_quantity_class', Quantity)
if isinstance(self, quantity_subclass):
quantity_subclass, subok = self.__quantity_subclass__(unit)
if subok:
quantity_subclass = self.__class__
# We only want to propagate information from ``self`` to our new view,
# so obj should be a regular array. By using ``np.array``, we also
# convert python and numpy scalars, which cannot be viewed as arrays
# and thus not as Quantity either, to zero-dimensional arrays.
# (These are turned back into scalar in `.value`)
# Note that for an ndarray input, the np.array call takes only double
# ``obj.__class is np.ndarray``. So, not worth special-casing.
if obj is None:
obj = self.view(np.ndarray)
else:
obj = np.array(obj, copy=False)
# Take the view, set the unit, and update possible other properties
# such as ``info``, ``wrap_angle`` in `Longitude`, etc.
view = obj.view(quantity_subclass)
view._set_unit(unit)
view.__array_finalize__(self)
return view
def _set_unit(self, unit):
"""Set the unit.
This is used anywhere the unit is set or modified, i.e., in the
initilizer, in ``__imul__`` and ``__itruediv__`` for in-place
multiplication and division by another unit, as well as in
``__array_finalize__`` for wrapping up views. For Quantity, it just
sets the unit, but subclasses can override it to check that, e.g.,
a unit is consistent.
"""
if not isinstance(unit, UnitBase):
# Trying to go through a string ensures that, e.g., Magnitudes with
# dimensionless physical unit become Quantity with units of mag.
unit = Unit(str(unit), parse_strict='silent')
if not isinstance(unit, UnitBase):
raise UnitTypeError(
"{0} instances require {1} units, not {2} instances."
.format(type(self).__name__, UnitBase, type(unit)))
self._unit = unit
def __deepcopy__(self, memo):
# If we don't define this, ``copy.deepcopy(quantity)`` will
# return a bare Numpy array.
return self.copy()
def __reduce__(self):
# patch to pickle Quantity objects (ndarray subclasses), see
# http://www.mail-archive.com/[email protected]/msg02446.html
object_state = list(super().__reduce__())
object_state[2] = (object_state[2], self.__dict__)
return tuple(object_state)
def __setstate__(self, state):
# patch to unpickle Quantity objects (ndarray subclasses), see
# http://www.mail-archive.com/[email protected]/msg02446.html
nd_state, own_state = state
super().__setstate__(nd_state)
self.__dict__.update(own_state)
info = QuantityInfo()
def _to_value(self, unit, equivalencies=[]):
"""Helper method for to and to_value."""
if equivalencies == []:
equivalencies = self._equivalencies
return self.unit.to(unit, self.view(np.ndarray),
equivalencies=equivalencies)
def to(self, unit, equivalencies=[]):
"""
Return a new `~astropy.units.Quantity` object with the specified unit.
Parameters
----------
unit : `~astropy.units.UnitBase` instance, str
An object that represents the unit to convert to. Must be
an `~astropy.units.UnitBase` object or a string parseable
by the `~astropy.units` package.
equivalencies : list of equivalence pairs, optional
A list of equivalence pairs to try if the units are not
directly convertible. See :ref:`unit_equivalencies`.
If not provided or ``[]``, class default equivalencies will be used
(none for `~astropy.units.Quantity`, but may be set for subclasses)
If `None`, no equivalencies will be applied at all, not even any
set globally or within a context.
See also
--------
to_value : get the numerical value in a given unit.
"""
# We don't use `to_value` below since we always want to make a copy
# and don't want to slow down this method (esp. the scalar case).
unit = Unit(unit)
return self._new_view(self._to_value(unit, equivalencies), unit)
def to_value(self, unit=None, equivalencies=[]):
"""
The numerical value, possibly in a different unit.
Parameters
----------
unit : `~astropy.units.UnitBase` instance or str, optional
The unit in which the value should be given. If not given or `None`,
use the current unit.
equivalencies : list of equivalence pairs, optional
A list of equivalence pairs to try if the units are not directly
convertible (see :ref:`unit_equivalencies`). If not provided or
``[]``, class default equivalencies will be used (none for
`~astropy.units.Quantity`, but may be set for subclasses).
If `None`, no equivalencies will be applied at all, not even any
set globally or within a context.
Returns
-------
value : `~numpy.ndarray` or scalar
The value in the units specified. For arrays, this will be a view
of the data if no unit conversion was necessary.
See also
--------
to : Get a new instance in a different unit.
"""
if unit is None or unit is self.unit:
value = self.view(np.ndarray)
else:
unit = Unit(unit)
# We want a view if the unit does not change. One could check
# with "==", but that calculates the scale that we need anyway.
# TODO: would be better for `unit.to` to have an in-place flag.
try:
scale = self.unit._to(unit)
except Exception:
# Short-cut failed; try default (maybe equivalencies help).
value = self._to_value(unit, equivalencies)
else:
value = self.view(np.ndarray)
if not is_effectively_unity(scale):
# not in-place!
value = value * scale
return value if self.shape else value.item()
value = property(to_value,
doc="""The numerical value of this instance.
See also
--------
to_value : Get the numerical value in a given unit.
""")
@property
def unit(self):
"""
A `~astropy.units.UnitBase` object representing the unit of this
quantity.
"""
return self._unit
@property
def equivalencies(self):
"""
A list of equivalencies that will be applied by default during
unit conversions.
"""
return self._equivalencies
@property
def si(self):
"""
Returns a copy of the current `Quantity` instance with SI units. The
value of the resulting object will be scaled.
"""
si_unit = self.unit.si
return self._new_view(self.value * si_unit.scale,
si_unit / si_unit.scale)
@property
def cgs(self):
"""
Returns a copy of the current `Quantity` instance with CGS units. The
value of the resulting object will be scaled.
"""
cgs_unit = self.unit.cgs
return self._new_view(self.value * cgs_unit.scale,
cgs_unit / cgs_unit.scale)
@property
def isscalar(self):
"""
True if the `value` of this quantity is a scalar, or False if it
is an array-like object.
.. note::
This is subtly different from `numpy.isscalar` in that
`numpy.isscalar` returns False for a zero-dimensional array
(e.g. ``np.array(1)``), while this is True for quantities,
since quantities cannot represent true numpy scalars.
"""
return not self.shape
# This flag controls whether convenience conversion members, such
# as `q.m` equivalent to `q.to_value(u.m)` are available. This is
# not turned on on Quantity itself, but is on some subclasses of
# Quantity, such as `astropy.coordinates.Angle`.
_include_easy_conversion_members = False
@override__dir__
def __dir__(self):
"""
Quantities are able to directly convert to other units that
have the same physical type. This function is implemented in
order to make autocompletion still work correctly in IPython.
"""
if not self._include_easy_conversion_members:
return []
extra_members = set()
equivalencies = Unit._normalize_equivalencies(self.equivalencies)
for equivalent in self.unit._get_units_with_same_physical_type(
equivalencies):
extra_members.update(equivalent.names)
return extra_members
def __getattr__(self, attr):
"""
Quantities are able to directly convert to other units that
have the same physical type.
"""
if not self._include_easy_conversion_members:
raise AttributeError(
"'{0}' object has no '{1}' member".format(
self.__class__.__name__,
attr))
def get_virtual_unit_attribute():
registry = get_current_unit_registry().registry
to_unit = registry.get(attr, None)
if to_unit is None:
return None
try:
return self.unit.to(
to_unit, self.value, equivalencies=self.equivalencies)
except UnitsError:
return None
value = get_virtual_unit_attribute()
if value is None:
raise AttributeError(
"{0} instance has no attribute '{1}'".format(
self.__class__.__name__, attr))
else:
return value
# Equality (return False if units do not match) needs to be handled
# explicitly for numpy >=1.9, since it no longer traps errors.
def __eq__(self, other):
try:
try:
return super().__eq__(other)
except DeprecationWarning:
# We treat the DeprecationWarning separately, since it may
# mask another Exception. But we do not want to just use
# np.equal, since super's __eq__ treats recarrays correctly.
return np.equal(self, other)
except UnitsError:
return False
except TypeError:
return NotImplemented
def __ne__(self, other):
try:
try:
return super().__ne__(other)
except DeprecationWarning:
return np.not_equal(self, other)
except UnitsError:
return True
except TypeError:
return NotImplemented
# Arithmetic operations
def __mul__(self, other):
""" Multiplication between `Quantity` objects and other objects."""
if isinstance(other, (UnitBase, str)):
try:
return self._new_view(self.copy(), other * self.unit)
except UnitsError: # let other try to deal with it
return NotImplemented
return super().__mul__(other)
def __imul__(self, other):
"""In-place multiplication between `Quantity` objects and others."""
if isinstance(other, (UnitBase, str)):
self._set_unit(other * self.unit)
return self
return super().__imul__(other)
def __rmul__(self, other):
""" Right Multiplication between `Quantity` objects and other
objects.
"""
return self.__mul__(other)
def __truediv__(self, other):
""" Division between `Quantity` objects and other objects."""
if isinstance(other, (UnitBase, str)):
try:
return self._new_view(self.copy(), self.unit / other)
except UnitsError: # let other try to deal with it
return NotImplemented
return super().__truediv__(other)
def __itruediv__(self, other):
"""Inplace division between `Quantity` objects and other objects."""
if isinstance(other, (UnitBase, str)):
self._set_unit(self.unit / other)
return self
return super().__itruediv__(other)
def __rtruediv__(self, other):
""" Right Division between `Quantity` objects and other objects."""
if isinstance(other, (UnitBase, str)):
return self._new_view(1. / self.value, other / self.unit)
return super().__rtruediv__(other)
def __div__(self, other):
""" Division between `Quantity` objects. """
return self.__truediv__(other)
def __idiv__(self, other):
""" Division between `Quantity` objects. """
return self.__itruediv__(other)
def __rdiv__(self, other):
""" Division between `Quantity` objects. """
return self.__rtruediv__(other)
if not hasattr(np, 'divmod'): # NUMPY_LT_1_13
# In numpy 1.13, divmod goes via a ufunc and thus works without change.
def __divmod__(self, other):
other_value = self._to_own_unit(other)
result_tuple = divmod(self.value, other_value)
return (self._new_view(result_tuple[0], dimensionless_unscaled),
self._new_view(result_tuple[1]))
def __pow__(self, other):
if isinstance(other, Fraction):
# Avoid getting object arrays by raising the value to a Fraction.
return self._new_view(self.value ** float(other),
self.unit ** other)
return super().__pow__(other)
# For Py>=3.5
def __matmul__(self, other, reverse=False):
result_unit = self.unit * getattr(other, 'unit', dimensionless_unscaled)
result_array = np.matmul(self.value, getattr(other, 'value', other))
return self._new_view(result_array, result_unit)
def __rmatmul__(self, other):
result_unit = self.unit * getattr(other, 'unit', dimensionless_unscaled)
result_array = np.matmul(getattr(other, 'value', other), self.value)
return self._new_view(result_array, result_unit)
if NUMPY_LT_1_13:
# Pre-numpy 1.13, there was no np.positive ufunc and the copy done
# by ndarray did not properly work for scalar quantities.
def __pos__(self):
"""Plus the quantity."""
return self.copy()
else:
# In numpy 1.13, a np.positive ufunc exists, but ndarray.__pos__
# does not yet go through it, so we still need to define it, to allow
# subclasses to override it inside __array_ufunc__.
# Presumably, this can eventually be removed.
def __pos__(self):
"""Plus the quantity."""
return np.positive(self)
# other overrides of special functions
def __hash__(self):
return hash(self.value) ^ hash(self.unit)
def __iter__(self):
if self.isscalar:
raise TypeError(
"'{cls}' object with a scalar value is not iterable"
.format(cls=self.__class__.__name__))
# Otherwise return a generator
def quantity_iter():
for val in self.value:
yield self._new_view(val)
return quantity_iter()
def __getitem__(self, key):
try:
out = super().__getitem__(key)
except IndexError:
# We want zero-dimensional Quantity objects to behave like scalars,
# so they should raise a TypeError rather than an IndexError.
if self.isscalar:
raise TypeError(
"'{cls}' object with a scalar value does not support "
"indexing".format(cls=self.__class__.__name__))
else:
raise
# For single elements, ndarray.__getitem__ returns scalars; these
# need a new view as a Quantity.
if type(out) is not type(self):
out = self._new_view(out)
return out
def __setitem__(self, i, value):
# update indices in info if the info property has been accessed
# (in which case 'info' in self.__dict__ is True; this is guaranteed
# to be the case if we're part of a table).
if not self.isscalar and 'info' in self.__dict__:
self.info.adjust_indices(i, value, len(self))
self.view(np.ndarray).__setitem__(i, self._to_own_unit(value))
# __contains__ is OK
def __bool__(self):
"""Quantities should always be treated as non-False; there is too much
potential for ambiguity otherwise.
"""
warnings.warn('The truth value of a Quantity is ambiguous. '
'In the future this will raise a ValueError.',
AstropyDeprecationWarning)
return True
def __len__(self):
if self.isscalar:
raise TypeError("'{cls}' object with a scalar value has no "
"len()".format(cls=self.__class__.__name__))
else:
return len(self.value)
# Numerical types
def __float__(self):
try:
return float(self.to_value(dimensionless_unscaled))
except (UnitsError, TypeError):
raise TypeError('only dimensionless scalar quantities can be '
'converted to Python scalars')
def __int__(self):
try:
return int(self.to_value(dimensionless_unscaled))
except (UnitsError, TypeError):
raise TypeError('only dimensionless scalar quantities can be '
'converted to Python scalars')
def __index__(self):
# for indices, we do not want to mess around with scaling at all,
# so unlike for float, int, we insist here on unscaled dimensionless
try:
assert self.unit.is_unity()
return self.value.__index__()
except Exception:
raise TypeError('only integer dimensionless scalar quantities '
'can be converted to a Python index')
@property
def _unitstr(self):
if self.unit is None:
unitstr = _UNIT_NOT_INITIALISED
else:
unitstr = str(self.unit)
if unitstr:
unitstr = ' ' + unitstr
return unitstr
# Display
# TODO: we may want to add a hook for dimensionless quantities?
def __str__(self):
return '{0}{1:s}'.format(self.value, self._unitstr)
def __repr__(self):
prefixstr = '<' + self.__class__.__name__ + ' '
sep = ',' if NUMPY_LT_1_14 else ', '
arrstr = np.array2string(self.view(np.ndarray), separator=sep,
prefix=prefixstr)
return '{0}{1}{2:s}>'.format(prefixstr, arrstr, self._unitstr)
def _repr_latex_(self):
"""
Generate a latex representation of the quantity and its unit.
The behavior of this function can be altered via the
`numpy.set_printoptions` function and its various keywords. The
exception to this is the ``threshold`` keyword, which is controlled via
the ``[units.quantity]`` configuration item ``latex_array_threshold``.
This is treated separately because the numpy default of 1000 is too big
for most browsers to handle.
Returns
-------
lstr
A LaTeX string with the contents of this Quantity
"""
# need to do try/finally because "threshold" cannot be overridden
# with array2string
pops = np.get_printoptions()
format_spec = '.{}g'.format(pops['precision'])
def float_formatter(value):
return Latex.format_exponential_notation(value,
format_spec=format_spec)
try:
formatter = {'float_kind': float_formatter}
if conf.latex_array_threshold > -1:
np.set_printoptions(threshold=conf.latex_array_threshold,
formatter=formatter)
# the view is needed for the scalar case - value might be float
if NUMPY_LT_1_14: # style deprecated in 1.14
latex_value = np.array2string(
self.view(np.ndarray),
style=(float_formatter if self.dtype.kind == 'f'
else repr),
max_line_width=np.inf, separator=',~')
else:
latex_value = np.array2string(
self.view(np.ndarray),
max_line_width=np.inf, separator=',~')
latex_value = latex_value.replace('...', r'\dots')
finally:
np.set_printoptions(**pops)
# Format unit
# [1:-1] strips the '$' on either side needed for math mode
latex_unit = (self.unit._repr_latex_()[1:-1] # note this is unicode
if self.unit is not None
else _UNIT_NOT_INITIALISED)
return r'${0} \; {1}$'.format(latex_value, latex_unit)
def __format__(self, format_spec):
"""
Format quantities using the new-style python formatting codes
as specifiers for the number.
If the format specifier correctly applies itself to the value,
then it is used to format only the value. If it cannot be
applied to the value, then it is applied to the whole string.
"""
try:
value = format(self.value, format_spec)
full_format_spec = "s"
except ValueError:
value = self.value
full_format_spec = format_spec
return format("{0}{1:s}".format(value, self._unitstr),
full_format_spec)
def decompose(self, bases=[]):
"""
Generates a new `Quantity` with the units
decomposed. Decomposed units have only irreducible units in
them (see `astropy.units.UnitBase.decompose`).
Parameters
----------
bases : sequence of UnitBase, optional
The bases to decompose into. When not provided,
decomposes down to any irreducible units. When provided,
the decomposed result will only contain the given units.
This will raises a `~astropy.units.UnitsError` if it's not possible
to do so.
Returns
-------
newq : `~astropy.units.Quantity`
A new object equal to this quantity with units decomposed.
"""
return self._decompose(False, bases=bases)
def _decompose(self, allowscaledunits=False, bases=[]):
"""
Generates a new `Quantity` with the units decomposed. Decomposed
units have only irreducible units in them (see
`astropy.units.UnitBase.decompose`).
Parameters
----------
allowscaledunits : bool
If True, the resulting `Quantity` may have a scale factor
associated with it. If False, any scaling in the unit will
be subsumed into the value of the resulting `Quantity`
bases : sequence of UnitBase, optional
The bases to decompose into. When not provided,
decomposes down to any irreducible units. When provided,
the decomposed result will only contain the given units.
This will raises a `~astropy.units.UnitsError` if it's not possible
to do so.
Returns
-------
newq : `~astropy.units.Quantity`
A new object equal to this quantity with units decomposed.
"""
new_unit = self.unit.decompose(bases=bases)
# Be careful here because self.value usually is a view of self;
# be sure that the original value is not being modified.
if not allowscaledunits and hasattr(new_unit, 'scale'):
new_value = self.value * new_unit.scale
new_unit = new_unit / new_unit.scale
return self._new_view(new_value, new_unit)
else:
return self._new_view(self.copy(), new_unit)
# These functions need to be overridden to take into account the units
# Array conversion
# http://docs.scipy.org/doc/numpy/reference/arrays.ndarray.html#array-conversion
def item(self, *args):
return self._new_view(super().item(*args))
def tolist(self):
raise NotImplementedError("cannot make a list of Quantities. Get "
"list of values with q.value.list()")
def _to_own_unit(self, value, check_precision=True):
try:
_value = value.to_value(self.unit)
except AttributeError:
# We're not a Quantity, so let's try a more general conversion.
# Plain arrays will be converted to dimensionless in the process,
# but anything with a unit attribute will use that.
try:
_value = Quantity(value).to_value(self.unit)
except UnitsError as exc:
# last chance: if this was not something with a unit
# and is all 0, inf, or nan, we treat it as arbitrary unit.
if (not hasattr(value, 'unit') and
can_have_arbitrary_unit(value)):
_value = value
else:
raise exc
if check_precision:
value_dtype = getattr(value, 'dtype', None)
if self.dtype != value_dtype:
self_dtype_array = np.array(_value, self.dtype)
value_dtype_array = np.array(_value, dtype=value_dtype,
copy=False)
if not np.all(np.logical_or(self_dtype_array ==
value_dtype_array,
np.isnan(value_dtype_array))):
raise TypeError("cannot convert value type to array type "
"without precision loss")
return _value
def itemset(self, *args):
if len(args) == 0:
raise ValueError("itemset must have at least one argument")
self.view(np.ndarray).itemset(*(args[:-1] +
(self._to_own_unit(args[-1]),)))
def tostring(self, order='C'):
raise NotImplementedError("cannot write Quantities to string. Write "
"array with q.value.tostring(...).")
def tofile(self, fid, sep="", format="%s"):
raise NotImplementedError("cannot write Quantities to file. Write "
"array with q.value.tofile(...)")
def dump(self, file):
raise NotImplementedError("cannot dump Quantities to file. Write "
"array with q.value.dump()")
def dumps(self):
raise NotImplementedError("cannot dump Quantities to string. Write "
"array with q.value.dumps()")
# astype, byteswap, copy, view, getfield, setflags OK as is
def fill(self, value):
self.view(np.ndarray).fill(self._to_own_unit(value))
# Shape manipulation: resize cannot be done (does not own data), but
# shape, transpose, swapaxes, flatten, ravel, squeeze all OK. Only
# the flat iterator needs to be overwritten, otherwise single items are
# returned as numbers.
@property
def flat(self):
"""A 1-D iterator over the Quantity array.
This returns a ``QuantityIterator`` instance, which behaves the same
as the `~numpy.flatiter` instance returned by `~numpy.ndarray.flat`,
and is similar to, but not a subclass of, Python's built-in iterator
object.
"""
return QuantityIterator(self)
@flat.setter
def flat(self, value):
y = self.ravel()
y[:] = value
# Item selection and manipulation
# take, repeat, sort, compress, diagonal OK
def put(self, indices, values, mode='raise'):
self.view(np.ndarray).put(indices, self._to_own_unit(values), mode)
def choose(self, choices, out=None, mode='raise'):
raise NotImplementedError("cannot choose based on quantity. Choose "
"using array with q.value.choose(...)")
# ensure we do not return indices as quantities
def argsort(self, axis=-1, kind='quicksort', order=None):
return self.view(np.ndarray).argsort(axis=axis, kind=kind, order=order)
def searchsorted(self, v, *args, **kwargs):
return np.searchsorted(np.array(self),
self._to_own_unit(v, check_precision=False),
*args, **kwargs) # avoid numpy 1.6 problem
def argmax(self, axis=None, out=None):
return self.view(np.ndarray).argmax(axis, out=out)
def argmin(self, axis=None, out=None):
return self.view(np.ndarray).argmin(axis, out=out)
# Calculation -- override ndarray methods to take into account units.
# We use the corresponding numpy functions to evaluate the results, since
# the methods do not always allow calling with keyword arguments.
# For instance, np.array([0.,2.]).clip(a_min=0., a_max=1.) gives
# TypeError: 'a_max' is an invalid keyword argument for this function.
def _wrap_function(self, function, *args, unit=None, out=None, **kwargs):
"""Wrap a numpy function that processes self, returning a Quantity.
Parameters
----------
function : callable
Numpy function to wrap.
args : positional arguments
Any positional arguments to the function beyond the first argument
(which will be set to ``self``).
kwargs : keyword arguments
Keyword arguments to the function.
If present, the following arguments are treated specially:
unit : `~astropy.units.Unit`
Unit of the output result. If not given, the unit of ``self``.
out : `~astropy.units.Quantity`
A Quantity instance in which to store the output.
Notes
-----
Output should always be assigned via a keyword argument, otherwise
no proper account of the unit is taken.
Returns
-------
out : `~astropy.units.Quantity`
Result of the function call, with the unit set properly.
"""
if unit is None:
unit = self.unit
# Ensure we don't loop back by turning any Quantity into array views.
args = (self.value,) + tuple((arg.value if isinstance(arg, Quantity)
else arg) for arg in args)
if out is not None:
# If pre-allocated output is used, check it is suitable.
# This also returns array view, to ensure we don't loop back.
arrays = tuple(arg for arg in args if isinstance(arg, np.ndarray))
kwargs['out'] = check_output(out, unit, arrays, function=function)
# Apply the function and turn it back into a Quantity.
result = function(*args, **kwargs)
return self._result_as_quantity(result, unit, out)
def clip(self, a_min, a_max, out=None):
return self._wrap_function(np.clip, self._to_own_unit(a_min),
self._to_own_unit(a_max), out=out)
def trace(self, offset=0, axis1=0, axis2=1, dtype=None, out=None):
return self._wrap_function(np.trace, offset, axis1, axis2, dtype,
out=out)
def var(self, axis=None, dtype=None, out=None, ddof=0):
return self._wrap_function(np.var, axis, dtype,
out=out, ddof=ddof, unit=self.unit**2)
def std(self, axis=None, dtype=None, out=None, ddof=0):
return self._wrap_function(np.std, axis, dtype, out=out, ddof=ddof)
def mean(self, axis=None, dtype=None, out=None):
return self._wrap_function(np.mean, axis, dtype, out=out)
def ptp(self, axis=None, out=None):
return self._wrap_function(np.ptp, axis, out=out)
def round(self, decimals=0, out=None):
return self._wrap_function(np.round, decimals, out=out)
def max(self, axis=None, out=None, keepdims=False):
return self._wrap_function(np.max, axis, out=out, keepdims=keepdims)
def min(self, axis=None, out=None, keepdims=False):
return self._wrap_function(np.min, axis, out=out, keepdims=keepdims)
def sum(self, axis=None, dtype=None, out=None, keepdims=False):
return self._wrap_function(np.sum, axis, dtype, out=out,
keepdims=keepdims)
def prod(self, axis=None, dtype=None, out=None, keepdims=False):
if not self.unit.is_unity():
raise ValueError("cannot use prod on scaled or "
"non-dimensionless Quantity arrays")
return self._wrap_function(np.prod, axis, dtype, out=out,
keepdims=keepdims)
def dot(self, b, out=None):
result_unit = self.unit * getattr(b, 'unit', dimensionless_unscaled)
return self._wrap_function(np.dot, b, out=out, unit=result_unit)
def cumsum(self, axis=None, dtype=None, out=None):
return self._wrap_function(np.cumsum, axis, dtype, out=out)
def cumprod(self, axis=None, dtype=None, out=None):
if not self.unit.is_unity():
raise ValueError("cannot use cumprod on scaled or "
"non-dimensionless Quantity arrays")
return self._wrap_function(np.cumprod, axis, dtype, out=out)
# Calculation: override methods that do not make sense.
def all(self, axis=None, out=None):
raise NotImplementedError("cannot evaluate truth value of quantities. "
"Evaluate array with q.value.all(...)")
def any(self, axis=None, out=None):
raise NotImplementedError("cannot evaluate truth value of quantities. "
"Evaluate array with q.value.any(...)")
# Calculation: numpy functions that can be overridden with methods.
def diff(self, n=1, axis=-1):
return self._wrap_function(np.diff, n, axis)
def ediff1d(self, to_end=None, to_begin=None):
return self._wrap_function(np.ediff1d, to_end, to_begin)
def nansum(self, axis=None, out=None, keepdims=False):
return self._wrap_function(np.nansum, axis,
out=out, keepdims=keepdims)
def insert(self, obj, values, axis=None):
"""
Insert values along the given axis before the given indices and return
a new `~astropy.units.Quantity` object.
This is a thin wrapper around the `numpy.insert` function.
Parameters
----------
obj : int, slice or sequence of ints
Object that defines the index or indices before which ``values`` is
inserted.
values : array-like
Values to insert. If the type of ``values`` is different
from that of quantity, ``values`` is converted to the matching type.
``values`` should be shaped so that it can be broadcast appropriately
The unit of ``values`` must be consistent with this quantity.
axis : int, optional
Axis along which to insert ``values``. If ``axis`` is None then
the quantity array is flattened before insertion.
Returns
-------
out : `~astropy.units.Quantity`
A copy of quantity with ``values`` inserted. Note that the
insertion does not occur in-place: a new quantity array is returned.
Examples
--------
>>> import astropy.units as u
>>> q = [1, 2] * u.m
>>> q.insert(0, 50 * u.cm)
<Quantity [ 0.5, 1., 2.] m>
>>> q = [[1, 2], [3, 4]] * u.m
>>> q.insert(1, [10, 20] * u.m, axis=0)
<Quantity [[ 1., 2.],
[ 10., 20.],
[ 3., 4.]] m>
>>> q.insert(1, 10 * u.m, axis=1)
<Quantity [[ 1., 10., 2.],
[ 3., 10., 4.]] m>
"""
out_array = np.insert(self.value, obj, self._to_own_unit(values), axis)
return self._new_view(out_array)
class SpecificTypeQuantity(Quantity):
"""Superclass for Quantities of specific physical type.
Subclasses of these work just like :class:`~astropy.units.Quantity`, except
that they are for specific physical types (and may have methods that are
only appropriate for that type). Astropy examples are
:class:`~astropy.coordinates.Angle` and
:class:`~astropy.coordinates.Distance`
At a minimum, subclasses should set ``_equivalent_unit`` to the unit
associated with the physical type.
"""
# The unit for the specific physical type. Instances can only be created
# with units that are equivalent to this.
_equivalent_unit = None
# The default unit used for views. Even with `None`, views of arrays
# without units are possible, but will have an uninitalized unit.
_unit = None
# Default unit for initialization through the constructor.
_default_unit = None
# ensure that we get precedence over our superclass.
__array_priority__ = Quantity.__array_priority__ + 10
def __quantity_subclass__(self, unit):
if unit.is_equivalent(self._equivalent_unit):
return type(self), True
else:
return super().__quantity_subclass__(unit)[0], False
def _set_unit(self, unit):
if unit is None or not unit.is_equivalent(self._equivalent_unit):
raise UnitTypeError(
"{0} instances require units equivalent to '{1}'"
.format(type(self).__name__, self._equivalent_unit) +
(", but no unit was given." if unit is None else
", so cannot set it to '{0}'.".format(unit)))
super()._set_unit(unit)
|
a1094edb71bd0130c16b3df31ee6148ba85165dbb06ee16b467627149dc4db06 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This package defines the SI units. They are also available in the
`astropy.units` namespace.
"""
from ..constants import si as _si
from .core import UnitBase, Unit, def_unit
import numpy as _numpy
_ns = globals()
###########################################################################
# DIMENSIONLESS
def_unit(['percent', 'pct'], Unit(0.01), namespace=_ns, prefixes=False,
doc="percent: one hundredth of unity, factor 0.01",
format={'generic': '%', 'console': '%', 'cds': '%',
'latex': r'\%', 'unicode': '%'})
###########################################################################
# LENGTH
def_unit(['m', 'meter'], namespace=_ns, prefixes=True,
doc="meter: base unit of length in SI")
def_unit(['micron'], um, namespace=_ns,
doc="micron: alias for micrometer (um)",
format={'latex': r'\mu m', 'unicode': 'μm'})
def_unit(['Angstrom', 'AA', 'angstrom'], 0.1 * nm, namespace=_ns,
doc="ångström: 10 ** -10 m",
format={'latex': r'\mathring{A}', 'unicode': 'Å',
'vounit': 'Angstrom'})
###########################################################################
# VOLUMES
def_unit((['l', 'L'], ['liter']), 1000 * cm ** 3.0, namespace=_ns, prefixes=True,
format={'latex': r'\mathcal{l}', 'unicode': 'ℓ'},
doc="liter: metric unit of volume")
###########################################################################
# ANGULAR MEASUREMENTS
def_unit(['rad', 'radian'], namespace=_ns, prefixes=True,
doc="radian: angular measurement of the ratio between the length "
"on an arc and its radius")
def_unit(['deg', 'degree'], _numpy.pi / 180.0 * rad, namespace=_ns,
prefixes=True,
doc="degree: angular measurement 1/360 of full rotation",
format={'latex': r'{}^{\circ}', 'unicode': '°'})
def_unit(['hourangle'], 15.0 * deg, namespace=_ns, prefixes=False,
doc="hour angle: angular measurement with 24 in a full circle",
format={'latex': r'{}^{h}', 'unicode': 'ʰ'})
def_unit(['arcmin', 'arcminute'], 1.0 / 60.0 * deg, namespace=_ns,
prefixes=True,
doc="arc minute: angular measurement",
format={'latex': r'{}^{\prime}', 'unicode': '′'})
def_unit(['arcsec', 'arcsecond'], 1.0 / 3600.0 * deg, namespace=_ns,
prefixes=True,
doc="arc second: angular measurement")
# These special formats should only be used for the non-prefix versions
arcsec._format = {'latex': r'{}^{\prime\prime}', 'unicode': '″'}
def_unit(['mas'], 0.001 * arcsec, namespace=_ns,
doc="milli arc second: angular measurement")
def_unit(['uas'], 0.000001 * arcsec, namespace=_ns,
doc="micro arc second: angular measurement",
format={'latex': r'\mu as', 'unicode': 'μas'})
def_unit(['sr', 'steradian'], rad ** 2, namespace=_ns, prefixes=True,
doc="steradian: unit of solid angle in SI")
###########################################################################
# TIME
def_unit(['s', 'second'], namespace=_ns, prefixes=True,
exclude_prefixes=['a'],
doc="second: base unit of time in SI.")
def_unit(['min', 'minute'], 60 * s, prefixes=True, namespace=_ns)
def_unit(['h', 'hour', 'hr'], 3600 * s, namespace=_ns, prefixes=True,
exclude_prefixes=['p'])
def_unit(['d', 'day'], 24 * h, namespace=_ns, prefixes=True,
exclude_prefixes=['c', 'y'])
def_unit(['sday'], 86164.09053 * s, namespace=_ns,
doc="Sidereal day (sday) is the time of one rotation of the Earth.")
def_unit(['wk', 'week'], 7 * day, namespace=_ns)
def_unit(['fortnight'], 2 * wk, namespace=_ns)
def_unit(['a', 'annum'], 365.25 * d, namespace=_ns, prefixes=True,
exclude_prefixes=['P'])
def_unit(['yr', 'year'], 365.25 * d, namespace=_ns, prefixes=True)
###########################################################################
# FREQUENCY
def_unit(['Hz', 'Hertz', 'hertz'], 1 / s, namespace=_ns, prefixes=True,
doc="Frequency")
###########################################################################
# MASS
def_unit(['kg', 'kilogram'], namespace=_ns,
doc="kilogram: base unit of mass in SI.")
def_unit(['g', 'gram'], 1.0e-3 * kg, namespace=_ns, prefixes=True,
exclude_prefixes=['k', 'kilo'])
def_unit(['t', 'tonne'], 1000 * kg, namespace=_ns,
doc="Metric tonne")
###########################################################################
# AMOUNT OF SUBSTANCE
def_unit(['mol', 'mole'], namespace=_ns, prefixes=True,
doc="mole: amount of a chemical substance in SI.")
###########################################################################
# TEMPERATURE
def_unit(
['K', 'Kelvin'], namespace=_ns, prefixes=True,
doc="Kelvin: temperature with a null point at absolute zero.")
def_unit(
['deg_C', 'Celsius'], namespace=_ns, doc='Degrees Celsius',
format={'latex': r'{}^{\circ}C', 'unicode': '°C'})
###########################################################################
# FORCE
def_unit(['N', 'Newton', 'newton'], kg * m * s ** -2, namespace=_ns,
prefixes=True, doc="Newton: force")
##########################################################################
# ENERGY
def_unit(['J', 'Joule', 'joule'], N * m, namespace=_ns, prefixes=True,
doc="Joule: energy")
def_unit(['eV', 'electronvolt'], _si.e.value * J, namespace=_ns, prefixes=True,
doc="Electron Volt")
##########################################################################
# PRESSURE
def_unit(['Pa', 'Pascal', 'pascal'], J * m ** -3, namespace=_ns, prefixes=True,
doc="Pascal: pressure")
def_unit(['bar'], 1e5 * Pa, namespace=_ns,
doc="bar: pressure")
###########################################################################
# POWER
def_unit(['W', 'Watt', 'watt'], J / s, namespace=_ns, prefixes=True,
doc="Watt: power")
###########################################################################
# ELECTRICAL
def_unit(['A', 'ampere', 'amp'], namespace=_ns, prefixes=True,
doc="ampere: base unit of electric current in SI")
def_unit(['C', 'coulomb'], A * s, namespace=_ns, prefixes=True,
doc="coulomb: electric charge")
def_unit(['V', 'Volt', 'volt'], J * C ** -1, namespace=_ns, prefixes=True,
doc="Volt: electric potential or electromotive force")
def_unit((['Ohm', 'ohm'], ['Ohm']), V * A ** -1, namespace=_ns, prefixes=True,
doc="Ohm: electrical resistance",
format={'latex': r'\Omega', 'unicode': 'Ω'})
def_unit(['S', 'Siemens', 'siemens'], A * V ** -1, namespace=_ns,
prefixes=True, doc="Siemens: electrical conductance")
def_unit(['F', 'Farad', 'farad'], C * V ** -1, namespace=_ns, prefixes=True,
doc="Farad: electrical capacitance")
###########################################################################
# MAGNETIC
def_unit(['Wb', 'Weber', 'weber'], V * s, namespace=_ns, prefixes=True,
doc="Weber: magnetic flux")
def_unit(['T', 'Tesla', 'tesla'], Wb * m ** -2, namespace=_ns, prefixes=True,
doc="Tesla: magnetic flux density")
def_unit(['H', 'Henry', 'henry'], Wb * A ** -1, namespace=_ns, prefixes=True,
doc="Henry: inductance")
###########################################################################
# ILLUMINATION
def_unit(['cd', 'candela'], namespace=_ns, prefixes=True,
doc="candela: base unit of luminous intensity in SI")
def_unit(['lm', 'lumen'], cd * sr, namespace=_ns, prefixes=True,
doc="lumen: luminous flux")
def_unit(['lx', 'lux'], lm * m ** -2, namespace=_ns, prefixes=True,
doc="lux: luminous emittence")
###########################################################################
# RADIOACTIVITY
def_unit(['Bq', 'becquerel'], Hz, namespace=_ns, prefixes=False,
doc="becquerel: unit of radioactivity")
def_unit(['Ci', 'curie'], Bq * 3.7e10, namespace=_ns, prefixes=False,
doc="curie: unit of radioactivity")
###########################################################################
# BASES
bases = set([m, s, kg, A, cd, rad, K, mol])
###########################################################################
# CLEANUP
del UnitBase
del Unit
del def_unit
###########################################################################
# DOCSTRING
# This generates a docstring for this module that describes all of the
# standard units defined here.
from .utils import generate_unit_summary as _generate_unit_summary
if __doc__ is not None:
__doc__ += _generate_unit_summary(globals())
|
54883c28ada7e386c882b4e18bc6726bf2a8292ccefc473eb7f13af21a71dd35 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""A set of standard astronomical equivalencies."""
# THIRD-PARTY
import numpy as np
import warnings
# LOCAL
from ..constants import si as _si
from . import si
from . import cgs
from . import astrophys
from .function import units as function_units
from . import dimensionless_unscaled
from .core import UnitsError, Unit
__all__ = ['parallax', 'spectral', 'spectral_density', 'doppler_radio',
'doppler_optical', 'doppler_relativistic', 'mass_energy',
'brightness_temperature', 'beam_angular_area',
'dimensionless_angles', 'logarithmic', 'temperature',
'temperature_energy', 'molar_mass_amu', 'pixel_scale',
'plate_scale']
def dimensionless_angles():
"""Allow angles to be equivalent to dimensionless (with 1 rad = 1 m/m = 1).
It is special compared to other equivalency pairs in that it
allows this independent of the power to which the angle is raised,
and independent of whether it is part of a more complicated unit.
"""
return [(si.radian, None)]
def logarithmic():
"""Allow logarithmic units to be converted to dimensionless fractions"""
return [
(dimensionless_unscaled, function_units.dex,
np.log10, lambda x: 10.**x)
]
def parallax():
"""
Returns a list of equivalence pairs that handle the conversion
between parallax angle and distance.
"""
return [
(si.arcsecond, astrophys.parsec, lambda x: 1. / x)
]
def spectral():
"""
Returns a list of equivalence pairs that handle spectral
wavelength, wave number, frequency, and energy equivalences.
Allows conversions between wavelength units, wave number units,
frequency units, and energy units as they relate to light.
There are two types of wave number:
* spectroscopic - :math:`1 / \\lambda` (per meter)
* angular - :math:`2 \\pi / \\lambda` (radian per meter)
"""
hc = _si.h.value * _si.c.value
two_pi = 2.0 * np.pi
inv_m_spec = si.m ** -1
inv_m_ang = si.radian / si.m
return [
(si.m, si.Hz, lambda x: _si.c.value / x),
(si.m, si.J, lambda x: hc / x),
(si.Hz, si.J, lambda x: _si.h.value * x, lambda x: x / _si.h.value),
(si.m, inv_m_spec, lambda x: 1.0 / x),
(si.Hz, inv_m_spec, lambda x: x / _si.c.value,
lambda x: _si.c.value * x),
(si.J, inv_m_spec, lambda x: x / hc, lambda x: hc * x),
(inv_m_spec, inv_m_ang, lambda x: x * two_pi, lambda x: x / two_pi),
(si.m, inv_m_ang, lambda x: two_pi / x),
(si.Hz, inv_m_ang, lambda x: two_pi * x / _si.c.value,
lambda x: _si.c.value * x / two_pi),
(si.J, inv_m_ang, lambda x: x * two_pi / hc, lambda x: hc * x / two_pi)
]
def spectral_density(wav, factor=None):
"""
Returns a list of equivalence pairs that handle spectral density
with regard to wavelength and frequency.
Parameters
----------
wav : `~astropy.units.Quantity`
`~astropy.units.Quantity` associated with values being converted
(e.g., wavelength or frequency).
Notes
-----
The ``factor`` argument is left for backward-compatibility with the syntax
``spectral_density(unit, factor)`` but users are encouraged to use
``spectral_density(factor * unit)`` instead.
"""
from .core import UnitBase
if isinstance(wav, UnitBase):
if factor is None:
raise ValueError(
'If `wav` is specified as a unit, `factor` should be set')
wav = factor * wav # Convert to Quantity
c_Aps = _si.c.to_value(si.AA / si.s) # Angstrom/s
h_cgs = _si.h.cgs.value # erg * s
hc = c_Aps * h_cgs
# flux density
f_la = cgs.erg / si.angstrom / si.cm ** 2 / si.s
f_nu = cgs.erg / si.Hz / si.cm ** 2 / si.s
nu_f_nu = cgs.erg / si.cm ** 2 / si.s
la_f_la = nu_f_nu
phot_f_la = astrophys.photon / (si.cm ** 2 * si.s * si.AA)
phot_f_nu = astrophys.photon / (si.cm ** 2 * si.s * si.Hz)
# luminosity density
L_nu = cgs.erg / si.s / si.Hz
L_la = cgs.erg / si.s / si.angstrom
nu_L_nu = cgs.erg / si.s
la_L_la = nu_L_nu
phot_L_la = astrophys.photon / (si.s * si.AA)
phot_L_nu = astrophys.photon / (si.s * si.Hz)
def converter(x):
return x * (wav.to_value(si.AA, spectral()) ** 2 / c_Aps)
def iconverter(x):
return x / (wav.to_value(si.AA, spectral()) ** 2 / c_Aps)
def converter_f_nu_to_nu_f_nu(x):
return x * wav.to_value(si.Hz, spectral())
def iconverter_f_nu_to_nu_f_nu(x):
return x / wav.to_value(si.Hz, spectral())
def converter_f_la_to_la_f_la(x):
return x * wav.to_value(si.AA, spectral())
def iconverter_f_la_to_la_f_la(x):
return x / wav.to_value(si.AA, spectral())
def converter_phot_f_la_to_f_la(x):
return hc * x / wav.to_value(si.AA, spectral())
def iconverter_phot_f_la_to_f_la(x):
return x * wav.to_value(si.AA, spectral()) / hc
def converter_phot_f_la_to_f_nu(x):
return h_cgs * x * wav.to_value(si.AA, spectral())
def iconverter_phot_f_la_to_f_nu(x):
return x / (wav.to_value(si.AA, spectral()) * h_cgs)
def converter_phot_f_la_phot_f_nu(x):
return x * wav.to_value(si.AA, spectral()) ** 2 / c_Aps
def iconverter_phot_f_la_phot_f_nu(x):
return c_Aps * x / wav.to_value(si.AA, spectral()) ** 2
converter_phot_f_nu_to_f_nu = converter_phot_f_la_to_f_la
iconverter_phot_f_nu_to_f_nu = iconverter_phot_f_la_to_f_la
def converter_phot_f_nu_to_f_la(x):
return x * hc * c_Aps / wav.to_value(si.AA, spectral()) ** 3
def iconverter_phot_f_nu_to_f_la(x):
return x * wav.to_value(si.AA, spectral()) ** 3 / (hc * c_Aps)
# for luminosity density
converter_L_nu_to_nu_L_nu = converter_f_nu_to_nu_f_nu
iconverter_L_nu_to_nu_L_nu = iconverter_f_nu_to_nu_f_nu
converter_L_la_to_la_L_la = converter_f_la_to_la_f_la
iconverter_L_la_to_la_L_la = iconverter_f_la_to_la_f_la
converter_phot_L_la_to_L_la = converter_phot_f_la_to_f_la
iconverter_phot_L_la_to_L_la = iconverter_phot_f_la_to_f_la
converter_phot_L_la_to_L_nu = converter_phot_f_la_to_f_nu
iconverter_phot_L_la_to_L_nu = iconverter_phot_f_la_to_f_nu
converter_phot_L_la_phot_L_nu = converter_phot_f_la_phot_f_nu
iconverter_phot_L_la_phot_L_nu = iconverter_phot_f_la_phot_f_nu
converter_phot_L_nu_to_L_nu = converter_phot_f_nu_to_f_nu
iconverter_phot_L_nu_to_L_nu = iconverter_phot_f_nu_to_f_nu
converter_phot_L_nu_to_L_la = converter_phot_f_nu_to_f_la
iconverter_phot_L_nu_to_L_la = iconverter_phot_f_nu_to_f_la
return [
# flux
(f_la, f_nu, converter, iconverter),
(f_nu, nu_f_nu, converter_f_nu_to_nu_f_nu, iconverter_f_nu_to_nu_f_nu),
(f_la, la_f_la, converter_f_la_to_la_f_la, iconverter_f_la_to_la_f_la),
(phot_f_la, f_la, converter_phot_f_la_to_f_la, iconverter_phot_f_la_to_f_la),
(phot_f_la, f_nu, converter_phot_f_la_to_f_nu, iconverter_phot_f_la_to_f_nu),
(phot_f_la, phot_f_nu, converter_phot_f_la_phot_f_nu, iconverter_phot_f_la_phot_f_nu),
(phot_f_nu, f_nu, converter_phot_f_nu_to_f_nu, iconverter_phot_f_nu_to_f_nu),
(phot_f_nu, f_la, converter_phot_f_nu_to_f_la, iconverter_phot_f_nu_to_f_la),
# luminosity
(L_la, L_nu, converter, iconverter),
(L_nu, nu_L_nu, converter_L_nu_to_nu_L_nu, iconverter_L_nu_to_nu_L_nu),
(L_la, la_L_la, converter_L_la_to_la_L_la, iconverter_L_la_to_la_L_la),
(phot_L_la, L_la, converter_phot_L_la_to_L_la, iconverter_phot_L_la_to_L_la),
(phot_L_la, L_nu, converter_phot_L_la_to_L_nu, iconverter_phot_L_la_to_L_nu),
(phot_L_la, phot_L_nu, converter_phot_L_la_phot_L_nu, iconverter_phot_L_la_phot_L_nu),
(phot_L_nu, L_nu, converter_phot_L_nu_to_L_nu, iconverter_phot_L_nu_to_L_nu),
(phot_L_nu, L_la, converter_phot_L_nu_to_L_la, iconverter_phot_L_nu_to_L_la),
]
def doppler_radio(rest):
r"""
Return the equivalency pairs for the radio convention for velocity.
The radio convention for the relation between velocity and frequency is:
:math:`V = c \frac{f_0 - f}{f_0} ; f(V) = f_0 ( 1 - V/c )`
Parameters
----------
rest : `~astropy.units.Quantity`
Any quantity supported by the standard spectral equivalencies
(wavelength, energy, frequency, wave number).
References
----------
`NRAO site defining the conventions <http://www.gb.nrao.edu/~fghigo/gbtdoc/doppler.html>`_
Examples
--------
>>> import astropy.units as u
>>> CO_restfreq = 115.27120*u.GHz # rest frequency of 12 CO 1-0 in GHz
>>> radio_CO_equiv = u.doppler_radio(CO_restfreq)
>>> measured_freq = 115.2832*u.GHz
>>> radio_velocity = measured_freq.to(u.km/u.s, equivalencies=radio_CO_equiv)
>>> radio_velocity # doctest: +FLOAT_CMP
<Quantity -31.209092088877583 km / s>
"""
assert_is_spectral_unit(rest)
ckms = _si.c.to_value('km/s')
def to_vel_freq(x):
restfreq = rest.to_value(si.Hz, equivalencies=spectral())
return (restfreq-x) / (restfreq) * ckms
def from_vel_freq(x):
restfreq = rest.to_value(si.Hz, equivalencies=spectral())
voverc = x/ckms
return restfreq * (1-voverc)
def to_vel_wav(x):
restwav = rest.to_value(si.AA, spectral())
return (x-restwav) / (x) * ckms
def from_vel_wav(x):
restwav = rest.to_value(si.AA, spectral())
return restwav * ckms / (ckms-x)
def to_vel_en(x):
resten = rest.to_value(si.eV, equivalencies=spectral())
return (resten-x) / (resten) * ckms
def from_vel_en(x):
resten = rest.to_value(si.eV, equivalencies=spectral())
voverc = x/ckms
return resten * (1-voverc)
return [(si.Hz, si.km/si.s, to_vel_freq, from_vel_freq),
(si.AA, si.km/si.s, to_vel_wav, from_vel_wav),
(si.eV, si.km/si.s, to_vel_en, from_vel_en),
]
def doppler_optical(rest):
r"""
Return the equivalency pairs for the optical convention for velocity.
The optical convention for the relation between velocity and frequency is:
:math:`V = c \frac{f_0 - f}{f } ; f(V) = f_0 ( 1 + V/c )^{-1}`
Parameters
----------
rest : `~astropy.units.Quantity`
Any quantity supported by the standard spectral equivalencies
(wavelength, energy, frequency, wave number).
References
----------
`NRAO site defining the conventions <http://www.gb.nrao.edu/~fghigo/gbtdoc/doppler.html>`_
Examples
--------
>>> import astropy.units as u
>>> CO_restfreq = 115.27120*u.GHz # rest frequency of 12 CO 1-0 in GHz
>>> optical_CO_equiv = u.doppler_optical(CO_restfreq)
>>> measured_freq = 115.2832*u.GHz
>>> optical_velocity = measured_freq.to(u.km/u.s, equivalencies=optical_CO_equiv)
>>> optical_velocity # doctest: +FLOAT_CMP
<Quantity -31.20584348799674 km / s>
"""
assert_is_spectral_unit(rest)
ckms = _si.c.to_value('km/s')
def to_vel_freq(x):
restfreq = rest.to_value(si.Hz, equivalencies=spectral())
return ckms * (restfreq-x) / x
def from_vel_freq(x):
restfreq = rest.to_value(si.Hz, equivalencies=spectral())
voverc = x/ckms
return restfreq / (1+voverc)
def to_vel_wav(x):
restwav = rest.to_value(si.AA, spectral())
return ckms * (x/restwav-1)
def from_vel_wav(x):
restwav = rest.to_value(si.AA, spectral())
voverc = x/ckms
return restwav * (1+voverc)
def to_vel_en(x):
resten = rest.to_value(si.eV, equivalencies=spectral())
return ckms * (resten-x) / x
def from_vel_en(x):
resten = rest.to_value(si.eV, equivalencies=spectral())
voverc = x/ckms
return resten / (1+voverc)
return [(si.Hz, si.km/si.s, to_vel_freq, from_vel_freq),
(si.AA, si.km/si.s, to_vel_wav, from_vel_wav),
(si.eV, si.km/si.s, to_vel_en, from_vel_en),
]
def doppler_relativistic(rest):
r"""
Return the equivalency pairs for the relativistic convention for velocity.
The full relativistic convention for the relation between velocity and frequency is:
:math:`V = c \frac{f_0^2 - f^2}{f_0^2 + f^2} ; f(V) = f_0 \frac{\left(1 - (V/c)^2\right)^{1/2}}{(1+V/c)}`
Parameters
----------
rest : `~astropy.units.Quantity`
Any quantity supported by the standard spectral equivalencies
(wavelength, energy, frequency, wave number).
References
----------
`NRAO site defining the conventions <http://www.gb.nrao.edu/~fghigo/gbtdoc/doppler.html>`_
Examples
--------
>>> import astropy.units as u
>>> CO_restfreq = 115.27120*u.GHz # rest frequency of 12 CO 1-0 in GHz
>>> relativistic_CO_equiv = u.doppler_relativistic(CO_restfreq)
>>> measured_freq = 115.2832*u.GHz
>>> relativistic_velocity = measured_freq.to(u.km/u.s, equivalencies=relativistic_CO_equiv)
>>> relativistic_velocity # doctest: +FLOAT_CMP
<Quantity -31.207467619351537 km / s>
>>> measured_velocity = 1250 * u.km/u.s
>>> relativistic_frequency = measured_velocity.to(u.GHz, equivalencies=relativistic_CO_equiv)
>>> relativistic_frequency # doctest: +FLOAT_CMP
<Quantity 114.79156866993588 GHz>
>>> relativistic_wavelength = measured_velocity.to(u.mm, equivalencies=relativistic_CO_equiv)
>>> relativistic_wavelength # doctest: +FLOAT_CMP
<Quantity 2.6116243681798923 mm>
"""
assert_is_spectral_unit(rest)
ckms = _si.c.to_value('km/s')
def to_vel_freq(x):
restfreq = rest.to_value(si.Hz, equivalencies=spectral())
return (restfreq**2-x**2) / (restfreq**2+x**2) * ckms
def from_vel_freq(x):
restfreq = rest.to_value(si.Hz, equivalencies=spectral())
voverc = x/ckms
return restfreq * ((1-voverc) / (1+(voverc)))**0.5
def to_vel_wav(x):
restwav = rest.to_value(si.AA, spectral())
return (x**2-restwav**2) / (restwav**2+x**2) * ckms
def from_vel_wav(x):
restwav = rest.to_value(si.AA, spectral())
voverc = x/ckms
return restwav * ((1+voverc) / (1-voverc))**0.5
def to_vel_en(x):
resten = rest.to_value(si.eV, spectral())
return (resten**2-x**2) / (resten**2+x**2) * ckms
def from_vel_en(x):
resten = rest.to_value(si.eV, spectral())
voverc = x/ckms
return resten * ((1-voverc) / (1+(voverc)))**0.5
return [(si.Hz, si.km/si.s, to_vel_freq, from_vel_freq),
(si.AA, si.km/si.s, to_vel_wav, from_vel_wav),
(si.eV, si.km/si.s, to_vel_en, from_vel_en),
]
def molar_mass_amu():
"""
Returns the equivalence between amu and molar mass.
"""
return [
(si.g/si.mol, astrophys.u)
]
def mass_energy():
"""
Returns a list of equivalence pairs that handle the conversion
between mass and energy.
"""
return [(si.kg, si.J, lambda x: x * _si.c.value ** 2,
lambda x: x / _si.c.value ** 2),
(si.kg / si.m ** 2, si.J / si.m ** 2,
lambda x: x * _si.c.value ** 2,
lambda x: x / _si.c.value ** 2),
(si.kg / si.m ** 3, si.J / si.m ** 3,
lambda x: x * _si.c.value ** 2,
lambda x: x / _si.c.value ** 2),
(si.kg / si.s, si.J / si.s, lambda x: x * _si.c.value ** 2,
lambda x: x / _si.c.value ** 2),
]
def brightness_temperature(frequency, beam_area=None):
r"""
Defines the conversion between Jy/sr and "brightness temperature",
:math:`T_B`, in Kelvins. The brightness temperature is a unit very
commonly used in radio astronomy. See, e.g., "Tools of Radio Astronomy"
(Wilson 2009) eqn 8.16 and eqn 8.19 (these pages are available on `google
books
<http://books.google.com/books?id=9KHw6R8rQEMC&pg=PA179&source=gbs_toc_r&cad=4#v=onepage&q&f=false>`__).
:math:`T_B \equiv S_\nu / \left(2 k \nu^2 / c^2 \right)`
If the input is in Jy/beam or Jy (assuming it came from a single beam), the
beam area is essential for this computation: the brightness temperature is
inversely proportional to the beam area.
Parameters
----------
frequency : `~astropy.units.Quantity` with spectral units
The observed ``spectral`` equivalent `~astropy.units.Unit` (e.g.,
frequency or wavelength). The variable is named 'frequency' because it
is more commonly used in radio astronomy.
BACKWARD COMPATIBILITY NOTE: previous versions of the brightness
temperature equivalency used the keyword ``disp``, which is no longer
supported.
beam_area : angular area equivalent
Beam area in angular units, i.e. steradian equivalent
Examples
--------
Arecibo C-band beam::
>>> import numpy as np
>>> from astropy import units as u
>>> beam_sigma = 50*u.arcsec
>>> beam_area = 2*np.pi*(beam_sigma)**2
>>> freq = 5*u.GHz
>>> equiv = u.brightness_temperature(freq)
>>> (1*u.Jy/beam_area).to(u.K, equivalencies=equiv) # doctest: +FLOAT_CMP
<Quantity 3.526295144567176 K>
VLA synthetic beam::
>>> bmaj = 15*u.arcsec
>>> bmin = 15*u.arcsec
>>> fwhm_to_sigma = 1./(8*np.log(2))**0.5
>>> beam_area = 2.*np.pi*(bmaj*bmin*fwhm_to_sigma**2)
>>> freq = 5*u.GHz
>>> equiv = u.brightness_temperature(freq)
>>> (u.Jy/beam_area).to(u.K, equivalencies=equiv) # doctest: +FLOAT_CMP
<Quantity 217.2658703625732 K>
Any generic surface brightness:
>>> surf_brightness = 1e6*u.MJy/u.sr
>>> surf_brightness.to(u.K, equivalencies=u.brightness_temperature(500*u.GHz)) # doctest: +FLOAT_CMP
<Quantity 130.1931904778803 K>
"""
if frequency.unit.is_equivalent(si.sr):
if not beam_area.unit.is_equivalent(si.Hz):
raise ValueError("The inputs to `brightness_temperature` are "
"frequency and angular area.")
warnings.warn("The inputs to `brightness_temperature` have changed. "
"Frequency is now the first input, and angular area "
"is the second, optional input.",
DeprecationWarning)
frequency, beam_area = beam_area, frequency
nu = frequency.to(si.GHz, spectral())
if beam_area is not None:
beam = beam_area.to_value(si.sr)
def convert_Jy_to_K(x_jybm):
factor = (2 * _si.k_B * si.K * nu**2 / _si.c**2).to(astrophys.Jy).value
return (x_jybm / beam / factor)
def convert_K_to_Jy(x_K):
factor = (astrophys.Jy / (2 * _si.k_B * nu**2 / _si.c**2)).to(si.K).value
return (x_K * beam / factor)
return [(astrophys.Jy, si.K, convert_Jy_to_K, convert_K_to_Jy),
(astrophys.Jy/astrophys.beam, si.K, convert_Jy_to_K, convert_K_to_Jy)
]
else:
def convert_JySr_to_K(x_jysr):
factor = (2 * _si.k_B * si.K * nu**2 / _si.c**2).to(astrophys.Jy).value
return (x_jysr / factor)
def convert_K_to_JySr(x_K):
factor = (astrophys.Jy / (2 * _si.k_B * nu**2 / _si.c**2)).to(si.K).value
return (x_K / factor) # multiplied by 1x for 1 steradian
return [(astrophys.Jy/si.sr, si.K, convert_JySr_to_K, convert_K_to_JySr)]
def beam_angular_area(beam_area):
"""
Convert between the ``beam`` unit, which is commonly used to express the area
of a radio telescope resolution element, and an area on the sky.
This equivalency also supports direct conversion between ``Jy/beam`` and
``Jy/steradian`` units, since that is a common operation.
Parameters
----------
beam_area : angular area equivalent
The area of the beam in angular area units (e.g., steradians)
"""
return [(astrophys.beam, Unit(beam_area)),
(astrophys.beam**-1, Unit(beam_area)**-1),
(astrophys.Jy/astrophys.beam, astrophys.Jy/Unit(beam_area)),
]
def temperature():
"""Convert between Kelvin, Celsius, and Fahrenheit here because
Unit and CompositeUnit cannot do addition or subtraction properly.
"""
from .imperial import deg_F
return [
(si.K, si.deg_C, lambda x: x - 273.15, lambda x: x + 273.15),
(si.deg_C, deg_F, lambda x: x * 1.8 + 32.0, lambda x: (x - 32.0) / 1.8),
(si.K, deg_F, lambda x: (x - 273.15) * 1.8 + 32.0,
lambda x: ((x - 32.0) / 1.8) + 273.15)]
def temperature_energy():
"""Convert between Kelvin and keV(eV) to an equivalent amount."""
return [
(si.K, si.eV, lambda x: x / (_si.e.value / _si.k_B.value),
lambda x: x * (_si.e.value / _si.k_B.value))]
def assert_is_spectral_unit(value):
try:
value.to(si.Hz, spectral())
except (AttributeError, UnitsError) as ex:
raise UnitsError("The 'rest' value must be a spectral equivalent "
"(frequency, wavelength, or energy).")
def pixel_scale(pixscale):
"""
Convert between pixel distances (in units of ``pix``) and angular units,
given a particular ``pixscale``.
Parameters
----------
pixscale : `~astropy.units.Quantity`
The pixel scale either in units of angle/pixel or pixel/angle.
"""
if pixscale.unit.is_equivalent(si.arcsec/astrophys.pix):
pixscale_val = pixscale.to_value(si.radian/astrophys.pix)
elif pixscale.unit.is_equivalent(astrophys.pix/si.arcsec):
pixscale_val = (1/pixscale).to_value(si.radian/astrophys.pix)
else:
raise UnitsError("The pixel scale must be in angle/pixel or "
"pixel/angle")
return [(astrophys.pix, si.radian, lambda px: px*pixscale_val, lambda rad: rad/pixscale_val)]
def plate_scale(platescale):
"""
Convert between lengths (to be interpreted as lengths in the focal plane)
and angular units with a specified ``platescale``.
Parameters
----------
platescale : `~astropy.units.Quantity`
The pixel scale either in units of distance/pixel or distance/angle.
"""
if platescale.unit.is_equivalent(si.arcsec/si.m):
platescale_val = platescale.to_value(si.radian/si.m)
elif platescale.unit.is_equivalent(si.m/si.arcsec):
platescale_val = (1/platescale).to_value(si.radian/si.m)
else:
raise UnitsError("The pixel scale must be in angle/distance or "
"distance/angle")
return [(si.m, si.radian, lambda d: d*platescale_val, lambda rad: rad/platescale_val)]
|
48921bf628672772221f1eca1d7ef60f1adbd10d05570acc3585cea35228e72a | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module contains convenience functions for retrieving solar system
ephemerides from jplephem.
"""
from urllib.parse import urlparse
from collections import OrderedDict
import numpy as np
from .sky_coordinate import SkyCoord
from ..utils.data import download_file
from ..utils.decorators import classproperty
from ..utils.state import ScienceState
from ..utils import indent
from .. import units as u
from .. import _erfa as erfa
from ..constants import c as speed_of_light
from .representation import CartesianRepresentation
from .orbital_elements import calc_moon
from .builtin_frames import GCRS, ICRS
from .builtin_frames.utils import get_jd12
__all__ = ["get_body", "get_moon", "get_body_barycentric",
"get_body_barycentric_posvel", "solar_system_ephemeris"]
DEFAULT_JPL_EPHEMERIS = 'de430'
"""List of kernel pairs needed to calculate positions of a given object."""
BODY_NAME_TO_KERNEL_SPEC = OrderedDict(
(('sun', [(0, 10)]),
('mercury', [(0, 1), (1, 199)]),
('venus', [(0, 2), (2, 299)]),
('earth-moon-barycenter', [(0, 3)]),
('earth', [(0, 3), (3, 399)]),
('moon', [(0, 3), (3, 301)]),
('mars', [(0, 4)]),
('jupiter', [(0, 5)]),
('saturn', [(0, 6)]),
('uranus', [(0, 7)]),
('neptune', [(0, 8)]),
('pluto', [(0, 9)]))
)
"""Indices to the plan94 routine for the given object."""
PLAN94_BODY_NAME_TO_PLANET_INDEX = OrderedDict(
(('mercury', 1),
('venus', 2),
('earth-moon-barycenter', 3),
('mars', 4),
('jupiter', 5),
('saturn', 6),
('uranus', 7),
('neptune', 8)))
_EPHEMERIS_NOTE = """
You can either give an explicit ephemeris or use a default, which is normally
a built-in ephemeris that does not require ephemeris files. To change
the default to be the JPL ephemeris::
>>> from astropy.coordinates import solar_system_ephemeris
>>> solar_system_ephemeris.set('jpl') # doctest: +SKIP
Use of any JPL ephemeris requires the jplephem package
(https://pypi.python.org/pypi/jplephem).
If needed, the ephemeris file will be downloaded (and cached).
One can check which bodies are covered by a given ephemeris using::
>>> solar_system_ephemeris.bodies
('earth', 'sun', 'moon', 'mercury', 'venus', 'earth-moon-barycenter', 'mars', 'jupiter', 'saturn', 'uranus', 'neptune')
"""[1:-1]
class solar_system_ephemeris(ScienceState):
"""Default ephemerides for calculating positions of Solar-System bodies.
This can be one of the following::
- 'builtin': polynomial approximations to the orbital elements.
- 'de430' or 'de432s': short-cuts for recent JPL dynamical models.
- 'jpl': Alias for the default JPL ephemeris (currently, 'de430').
- URL: (str) The url to a SPK ephemeris in SPICE binary (.bsp) format.
- `None`: Ensure an Exception is raised without an explicit ephemeris.
The default is 'builtin', which uses the ``epv00`` and ``plan94``
routines from the ``erfa`` implementation of the Standards Of Fundamental
Astronomy library.
Notes
-----
Any file required will be downloaded (and cached) when the state is set.
The default Satellite Planet Kernel (SPK) file from NASA JPL (de430) is
~120MB, and covers years ~1550-2650 CE [1]_. The smaller de432s file is
~10MB, and covers years 1950-2050 [2]_. Older versions of the JPL
ephemerides (such as the widely used de200) can be used via their URL [3]_.
.. [1] http://naif.jpl.nasa.gov/pub/naif/generic_kernels/spk/planets/aareadme_de430-de431.txt
.. [2] http://naif.jpl.nasa.gov/pub/naif/generic_kernels/spk/planets/aareadme_de432s.txt
.. [3] http://naif.jpl.nasa.gov/pub/naif/generic_kernels/spk/planets/a_old_versions/
"""
_value = 'builtin'
_kernel = None
@classmethod
def validate(cls, value):
# make no changes if value is None
if value is None:
return cls._value
# Set up Kernel; if the file is not in cache, this will download it.
cls.get_kernel(value)
return value
@classmethod
def get_kernel(cls, value):
# ScienceState only ensures the `_value` attribute is up to date,
# so we need to be sure any kernel returned is consistent.
if cls._kernel is None or cls._kernel.origin != value:
if cls._kernel is not None:
cls._kernel.daf.file.close()
cls._kernel = None
kernel = _get_kernel(value)
if kernel is not None:
kernel.origin = value
cls._kernel = kernel
return cls._kernel
@classproperty
def kernel(cls):
return cls.get_kernel(cls._value)
@classproperty
def bodies(cls):
if cls._value is None:
return None
if cls._value.lower() == 'builtin':
return (('earth', 'sun', 'moon') +
tuple(PLAN94_BODY_NAME_TO_PLANET_INDEX.keys()))
else:
return tuple(BODY_NAME_TO_KERNEL_SPEC.keys())
def _get_kernel(value):
"""
Try importing jplephem, download/retrieve from cache the Satellite Planet
Kernel corresponding to the given ephemeris.
"""
if value is None or value.lower() == 'builtin':
return None
if value.lower() == 'jpl':
value = DEFAULT_JPL_EPHEMERIS
if value.lower() in ('de430', 'de432s'):
value = ('http://naif.jpl.nasa.gov/pub/naif/generic_kernels'
'/spk/planets/{:s}.bsp'.format(value.lower()))
else:
try:
urlparse(value)
except Exception:
raise ValueError('{} was not one of the standard strings and '
'could not be parsed as a URL'.format(value))
try:
from jplephem.spk import SPK
except ImportError:
raise ImportError("Solar system JPL ephemeris calculations require "
"the jplephem package "
"(https://pypi.python.org/pypi/jplephem)")
return SPK.open(download_file(value, cache=True))
def _get_body_barycentric_posvel(body, time, ephemeris=None,
get_velocity=True):
"""Calculate the barycentric position (and velocity) of a solar system body.
Parameters
----------
body : str or other
The solar system body for which to calculate positions. Can also be a
kernel specifier (list of 2-tuples) if the ``ephemeris`` is a JPL
kernel.
time : `~astropy.time.Time`
Time of observation.
ephemeris : str, optional
Ephemeris to use. By default, use the one set with
``astropy.coordinates.solar_system_ephemeris.set``
get_velocity : bool, optional
Whether or not to calculate the velocity as well as the position.
Returns
-------
position : `~astropy.coordinates.CartesianRepresentation` or tuple
Barycentric (ICRS) position or tuple of position and velocity.
Notes
-----
No velocity can be calculated with the built-in ephemeris for the Moon.
Whether or not velocities are calculated makes little difference for the
built-in ephemerides, but for most JPL ephemeris files, the execution time
roughly doubles.
"""
if ephemeris is None:
ephemeris = solar_system_ephemeris.get()
if ephemeris is None:
raise ValueError(_EPHEMERIS_NOTE)
kernel = solar_system_ephemeris.kernel
else:
kernel = _get_kernel(ephemeris)
jd1, jd2 = get_jd12(time, 'tdb')
if kernel is None:
body = body.lower()
earth_pv_helio, earth_pv_bary = erfa.epv00(jd1, jd2)
if body == 'earth':
body_pv_bary = earth_pv_bary
elif body == 'moon':
if get_velocity:
raise KeyError("the Moon's velocity cannot be calculated with "
"the '{0}' ephemeris.".format(ephemeris))
return calc_moon(time).cartesian
else:
sun_pv_bary = earth_pv_bary - earth_pv_helio
if body == 'sun':
body_pv_bary = sun_pv_bary
else:
try:
body_index = PLAN94_BODY_NAME_TO_PLANET_INDEX[body]
except KeyError:
raise KeyError("{0}'s position and velocity cannot be "
"calculated with the '{1}' ephemeris."
.format(body, ephemeris))
body_pv_helio = erfa.plan94(jd1, jd2, body_index)
body_pv_bary = body_pv_helio + sun_pv_bary
body_pos_bary = CartesianRepresentation(
body_pv_bary[..., 0, :], unit=u.au, xyz_axis=-1, copy=False)
if get_velocity:
body_vel_bary = CartesianRepresentation(
body_pv_bary[..., 1, :], unit=u.au/u.day, xyz_axis=-1,
copy=False)
else:
if isinstance(body, str):
# Look up kernel chain for JPL ephemeris, based on name
try:
kernel_spec = BODY_NAME_TO_KERNEL_SPEC[body.lower()]
except KeyError:
raise KeyError("{0}'s position cannot be calculated with "
"the {1} ephemeris.".format(body, ephemeris))
else:
# otherwise, assume the user knows what their doing and intentionally
# passed in a kernel chain
kernel_spec = body
# jplephem cannot handle multi-D arrays, so convert to 1D here.
jd1_shape = getattr(jd1, 'shape', ())
if len(jd1_shape) > 1:
jd1, jd2 = jd1.ravel(), jd2.ravel()
# Note that we use the new jd1.shape here to create a 1D result array.
# It is reshaped below.
body_posvel_bary = np.zeros((2 if get_velocity else 1, 3) +
getattr(jd1, 'shape', ()))
for pair in kernel_spec:
spk = kernel[pair]
if spk.data_type == 3:
# Type 3 kernels contain both position and velocity.
posvel = spk.compute(jd1, jd2)
if get_velocity:
body_posvel_bary += posvel.reshape(body_posvel_bary.shape)
else:
body_posvel_bary[0] += posvel[:4]
else:
# spk.generate first yields the position and then the
# derivative. If no velocities are desired, body_posvel_bary
# has only one element and thus the loop ends after a single
# iteration, avoiding the velocity calculation.
for body_p_or_v, p_or_v in zip(body_posvel_bary,
spk.generate(jd1, jd2)):
body_p_or_v += p_or_v
body_posvel_bary.shape = body_posvel_bary.shape[:2] + jd1_shape
body_pos_bary = CartesianRepresentation(body_posvel_bary[0],
unit=u.km, copy=False)
if get_velocity:
body_vel_bary = CartesianRepresentation(body_posvel_bary[1],
unit=u.km/u.day, copy=False)
return (body_pos_bary, body_vel_bary) if get_velocity else body_pos_bary
def get_body_barycentric_posvel(body, time, ephemeris=None):
"""Calculate the barycentric position and velocity of a solar system body.
Parameters
----------
body : str or other
The solar system body for which to calculate positions. Can also be a
kernel specifier (list of 2-tuples) if the ``ephemeris`` is a JPL
kernel.
time : `~astropy.time.Time`
Time of observation.
ephemeris : str, optional
Ephemeris to use. By default, use the one set with
``astropy.coordinates.solar_system_ephemeris.set``
Returns
-------
position, velocity : tuple of `~astropy.coordinates.CartesianRepresentation`
Tuple of barycentric (ICRS) position and velocity.
See also
--------
get_body_barycentric : to calculate position only.
This is faster by about a factor two for JPL kernels, but has no
speed advantage for the built-in ephemeris.
Notes
-----
The velocity cannot be calculated for the Moon. To just get the position,
use :func:`~astropy.coordinates.get_body_barycentric`.
"""
return _get_body_barycentric_posvel(body, time, ephemeris)
get_body_barycentric_posvel.__doc__ += indent(_EPHEMERIS_NOTE)[4:]
def get_body_barycentric(body, time, ephemeris=None):
"""Calculate the barycentric position of a solar system body.
Parameters
----------
body : str or other
The solar system body for which to calculate positions. Can also be a
kernel specifier (list of 2-tuples) if the ``ephemeris`` is a JPL
kernel.
time : `~astropy.time.Time`
Time of observation.
ephemeris : str, optional
Ephemeris to use. By default, use the one set with
``astropy.coordinates.solar_system_ephemeris.set``
Returns
-------
position : `~astropy.coordinates.CartesianRepresentation`
Barycentric (ICRS) position of the body in cartesian coordinates
See also
--------
get_body_barycentric_posvel : to calculate both position and velocity.
Notes
-----
"""
return _get_body_barycentric_posvel(body, time, ephemeris,
get_velocity=False)
get_body_barycentric.__doc__ += indent(_EPHEMERIS_NOTE)[4:]
def _get_apparent_body_position(body, time, ephemeris):
"""Calculate the apparent position of body ``body`` relative to Earth.
This corrects for the light-travel time to the object.
Parameters
----------
body : str or other
The solar system body for which to calculate positions. Can also be a
kernel specifier (list of 2-tuples) if the ``ephemeris`` is a JPL
kernel.
time : `~astropy.time.Time`
Time of observation.
ephemeris : str, optional
Ephemeris to use. By default, use the one set with
``~astropy.coordinates.solar_system_ephemeris.set``
Returns
-------
cartesian_position : `~astropy.coordinates.CartesianRepresentation`
Barycentric (ICRS) apparent position of the body in cartesian coordinates
"""
if ephemeris is None:
ephemeris = solar_system_ephemeris.get()
# builtin ephemeris and moon is a special case, with no need to account for
# light travel time, since this is already included in the Meeus algorithm
# used.
if ephemeris == 'builtin' and body.lower() == 'moon':
return get_body_barycentric(body, time, ephemeris)
# Calculate position given approximate light travel time.
delta_light_travel_time = 20. * u.s
emitted_time = time
light_travel_time = 0. * u.s
earth_loc = get_body_barycentric('earth', time, ephemeris)
while np.any(np.fabs(delta_light_travel_time) > 1.0e-8*u.s):
body_loc = get_body_barycentric(body, emitted_time, ephemeris)
earth_distance = (body_loc - earth_loc).norm()
delta_light_travel_time = (light_travel_time -
earth_distance/speed_of_light)
light_travel_time = earth_distance/speed_of_light
emitted_time = time - light_travel_time
return get_body_barycentric(body, emitted_time, ephemeris)
_get_apparent_body_position.__doc__ += indent(_EPHEMERIS_NOTE)[4:]
def get_body(body, time, location=None, ephemeris=None):
"""
Get a `~astropy.coordinates.SkyCoord` for a solar system body as observed
from a location on Earth in the `~astropy.coordinates.GCRS` reference
system.
Parameters
----------
body : str or other
The solar system body for which to calculate positions. Can also be a
kernel specifier (list of 2-tuples) if the ``ephemeris`` is a JPL
kernel.
time : `~astropy.time.Time`
Time of observation.
location : `~astropy.coordinates.EarthLocation`, optional
Location of observer on the Earth. If not given, will be taken from
``time`` (if not present, a geocentric observer will be assumed).
ephemeris : str, optional
Ephemeris to use. If not given, use the one set with
``astropy.coordinates.solar_system_ephemeris.set`` (which is
set to 'builtin' by default).
Returns
-------
skycoord : `~astropy.coordinates.SkyCoord`
GCRS Coordinate for the body
Notes
-----
"""
if location is None:
location = time.location
cartrep = _get_apparent_body_position(body, time, ephemeris)
icrs = ICRS(cartrep)
if location is not None:
obsgeoloc, obsgeovel = location.get_gcrs_posvel(time)
gcrs = icrs.transform_to(GCRS(obstime=time,
obsgeoloc=obsgeoloc,
obsgeovel=obsgeovel))
else:
gcrs = icrs.transform_to(GCRS(obstime=time))
return SkyCoord(gcrs)
get_body.__doc__ += indent(_EPHEMERIS_NOTE)[4:]
def get_moon(time, location=None, ephemeris=None):
"""
Get a `~astropy.coordinates.SkyCoord` for the Earth's Moon as observed
from a location on Earth in the `~astropy.coordinates.GCRS` reference
system.
Parameters
----------
time : `~astropy.time.Time`
Time of observation
location : `~astropy.coordinates.EarthLocation`
Location of observer on the Earth. If none is supplied, taken from
``time`` (if not present, a geocentric observer will be assumed).
ephemeris : str, optional
Ephemeris to use. If not given, use the one set with
``astropy.coordinates.solar_system_ephemeris.set`` (which is
set to 'builtin' by default).
Returns
-------
skycoord : `~astropy.coordinates.SkyCoord`
GCRS Coordinate for the Moon
Notes
-----
"""
return get_body('moon', time, location=location, ephemeris=ephemeris)
get_moon.__doc__ += indent(_EPHEMERIS_NOTE)[4:]
def _apparent_position_in_true_coordinates(skycoord):
"""
Convert Skycoord in GCRS frame into one in which RA and Dec
are defined w.r.t to the true equinox and poles of the Earth
"""
jd1, jd2 = get_jd12(skycoord.obstime, 'tt')
_, _, _, _, _, _, _, rbpn = erfa.pn00a(jd1, jd2)
return SkyCoord(skycoord.frame.realize_frame(
skycoord.cartesian.transform(rbpn)))
|
cb0e4d2b6ca097da8d53f9ff3afe57e2e43f9ffa4acd1699cb4a28e3c5e16d3c | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
''' This module defines custom errors and exceptions used in astropy.coordinates.
'''
from ..utils.exceptions import AstropyWarning
__all__ = ['RangeError', 'BoundsError', 'IllegalHourError',
'IllegalMinuteError', 'IllegalSecondError', 'ConvertError',
'IllegalHourWarning', 'IllegalMinuteWarning', 'IllegalSecondWarning',
'UnknownSiteException']
class RangeError(ValueError):
"""
Raised when some part of an angle is out of its valid range.
"""
class BoundsError(RangeError):
"""
Raised when an angle is outside of its user-specified bounds.
"""
class IllegalHourError(RangeError):
"""
Raised when an hour value is not in the range [0,24).
Parameters
----------
hour : int, float
Examples
--------
.. code-block:: python
if not 0 <= hr < 24:
raise IllegalHourError(hour)
"""
def __init__(self, hour):
self.hour = hour
def __str__(self):
return "An invalid value for 'hours' was found ('{0}'); must be in the range [0,24).".format(self.hour)
class IllegalHourWarning(AstropyWarning):
"""
Raised when an hour value is 24.
Parameters
----------
hour : int, float
"""
def __init__(self, hour, alternativeactionstr=None):
self.hour = hour
self.alternativeactionstr = alternativeactionstr
def __str__(self):
message = "'hour' was found to be '{0}', which is not in range (-24, 24).".format(self.hour)
if self.alternativeactionstr is not None:
message += ' ' + self.alternativeactionstr
return message
class IllegalMinuteError(RangeError):
"""
Raised when an minute value is not in the range [0,60].
Parameters
----------
minute : int, float
Examples
--------
.. code-block:: python
if not 0 <= min < 60:
raise IllegalMinuteError(minute)
"""
def __init__(self, minute):
self.minute = minute
def __str__(self):
return "An invalid value for 'minute' was found ('{0}'); should be in the range [0,60).".format(self.minute)
class IllegalMinuteWarning(AstropyWarning):
"""
Raised when a minute value is 60.
Parameters
----------
minute : int, float
"""
def __init__(self, minute, alternativeactionstr=None):
self.minute = minute
self.alternativeactionstr = alternativeactionstr
def __str__(self):
message = "'minute' was found to be '{0}', which is not in range [0,60).".format(self.minute)
if self.alternativeactionstr is not None:
message += ' ' + self.alternativeactionstr
return message
class IllegalSecondError(RangeError):
"""
Raised when an second value (time) is not in the range [0,60].
Parameters
----------
second : int, float
Examples
--------
.. code-block:: python
if not 0 <= sec < 60:
raise IllegalSecondError(second)
"""
def __init__(self, second):
self.second = second
def __str__(self):
return "An invalid value for 'second' was found ('{0}'); should be in the range [0,60).".format(self.second)
class IllegalSecondWarning(AstropyWarning):
"""
Raised when a second value is 60.
Parameters
----------
second : int, float
"""
def __init__(self, second, alternativeactionstr=None):
self.second = second
self.alternativeactionstr = alternativeactionstr
def __str__(self):
message = "'second' was found to be '{0}', which is not in range [0,60).".format(self.second)
if self.alternativeactionstr is not None:
message += ' ' + self.alternativeactionstr
return message
# TODO: consider if this should be used to `units`?
class UnitsError(ValueError):
"""
Raised if units are missing or invalid.
"""
class ConvertError(Exception):
"""
Raised if a coordinate system cannot be converted to another
"""
class UnknownSiteException(KeyError):
def __init__(self, site, attribute, close_names=None):
message = "Site '{0}' not in database. Use {1} to see available sites.".format(site, attribute)
if close_names:
message += " Did you mean one of: '{0}'?'".format("', '".join(close_names))
self.site = site
self.attribute = attribute
self.close_names = close_names
return super().__init__(message)
|
fb19f5cdbb75298b33439af8e94a135134ae1d9e92196ba74e3f6d2426431131 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module contains utililies used for constructing rotation matrices.
"""
from functools import reduce
import numpy as np
from .. import units as u
from .angles import Angle
def matrix_product(*matrices):
"""Matrix multiply all arguments together.
Arguments should have dimension 2 or larger. Larger dimensional objects
are interpreted as stacks of matrices residing in the last two dimensions.
This function mostly exists for readability: using `~numpy.matmul`
directly, one would have ``matmul(matmul(m1, m2), m3)``, etc. For even
better readability, one might consider using `~numpy.matrix` for the
arguments (so that one could write ``m1 * m2 * m3``), but then it is not
possible to handle stacks of matrices. Once only python >=3.5 is supported,
this function can be replaced by ``m1 @ m2 @ m3``.
"""
return reduce(np.matmul, matrices)
def matrix_transpose(matrix):
"""Transpose a matrix or stack of matrices by swapping the last two axes.
This function mostly exists for readability; seeing ``.swapaxes(-2, -1)``
it is not that obvious that one does a transpose. Note that one cannot
use `~numpy.ndarray.T`, as this transposes all axes and thus does not
work for stacks of matrices.
"""
return matrix.swapaxes(-2, -1)
def rotation_matrix(angle, axis='z', unit=None):
"""
Generate matrices for rotation by some angle around some axis.
Parameters
----------
angle : convertible to `Angle`
The amount of rotation the matrices should represent. Can be an array.
axis : str, or array-like
Either ``'x'``, ``'y'``, ``'z'``, or a (x,y,z) specifying the axis to
rotate about. If ``'x'``, ``'y'``, or ``'z'``, the rotation sense is
counterclockwise looking down the + axis (e.g. positive rotations obey
left-hand-rule). If given as an array, the last dimension should be 3;
it will be broadcast against ``angle``.
unit : UnitBase, optional
If ``angle`` does not have associated units, they are in this
unit. If neither are provided, it is assumed to be degrees.
Returns
-------
rmat : `numpy.matrix`
A unitary rotation matrix.
"""
if unit is None:
unit = u.degree
angle = Angle(angle, unit=unit)
s = np.sin(angle)
c = np.cos(angle)
# use optimized implementations for x/y/z
try:
i = 'xyz'.index(axis)
except TypeError:
axis = np.asarray(axis)
axis = axis / np.sqrt((axis * axis).sum(axis=-1, keepdims=True))
R = (axis[..., np.newaxis] * axis[..., np.newaxis, :] *
(1. - c)[..., np.newaxis, np.newaxis])
for i in range(0, 3):
R[..., i, i] += c
a1 = (i + 1) % 3
a2 = (i + 2) % 3
R[..., a1, a2] += axis[..., i] * s
R[..., a2, a1] -= axis[..., i] * s
else:
a1 = (i + 1) % 3
a2 = (i + 2) % 3
R = np.zeros(angle.shape + (3, 3))
R[..., i, i] = 1.
R[..., a1, a1] = c
R[..., a1, a2] = s
R[..., a2, a1] = -s
R[..., a2, a2] = c
return R
def angle_axis(matrix):
"""
Angle of rotation and rotation axis for a given rotation matrix.
Parameters
----------
matrix : array-like
A 3 x 3 unitary rotation matrix (or stack of matrices).
Returns
-------
angle : `Angle`
The angle of rotation.
axis : array
The (normalized) axis of rotation (with last dimension 3).
"""
m = np.asanyarray(matrix)
if m.shape[-2:] != (3, 3):
raise ValueError('matrix is not 3x3')
axis = np.zeros(m.shape[:-1])
axis[..., 0] = m[..., 2, 1] - m[..., 1, 2]
axis[..., 1] = m[..., 0, 2] - m[..., 2, 0]
axis[..., 2] = m[..., 1, 0] - m[..., 0, 1]
r = np.sqrt((axis * axis).sum(-1, keepdims=True))
angle = np.arctan2(r[..., 0],
m[..., 0, 0] + m[..., 1, 1] + m[..., 2, 2] - 1.)
return Angle(angle, u.radian), -axis / r
|
3127ebca0d0d42515657270590cef55fc0315a4aaab0e94e32efcc78b4e8f609 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This subpackage contains classes and functions for celestial coordinates
of astronomical objects. It also contains a framework for conversions
between coordinate systems.
"""
from .errors import *
from .angles import *
from .baseframe import *
from .attributes import *
from .distances import *
from .earth import *
from .transformations import *
from .builtin_frames import *
from .name_resolve import *
from .matching import *
from .representation import *
from .sky_coordinate import *
from .funcs import *
from .calculation import *
from .solar_system import *
# This is for backwards-compatibility -- can be removed in v3.0 when the
# deprecation warnings are removed
from .attributes import (TimeFrameAttribute, QuantityFrameAttribute,
CartesianRepresentationFrameAttribute)
__doc__ += builtin_frames._transform_graph_docs + """
.. note::
The ecliptic coordinate systems (added in Astropy v1.1) have not been
extensively tested for accuracy or consistency with other implementations of
ecliptic coordinates. We welcome contributions to add such testing, but in
the meantime, users who depend on consistency with other implementations may
wish to check test inputs against good datasets before using Astropy's
ecliptic coordinates.
"""
|
ee22ee7b96b8f340053f77c7ccee92c9cec20fe4c0baa0e79e0f9a19bfe32bce | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module contains functions for matching coordinate catalogs.
"""
import numpy as np
from .representation import UnitSphericalRepresentation
from .. import units as u
from . import Angle
__all__ = ['match_coordinates_3d', 'match_coordinates_sky', 'search_around_3d',
'search_around_sky']
def match_coordinates_3d(matchcoord, catalogcoord, nthneighbor=1, storekdtree='kdtree_3d'):
"""
Finds the nearest 3-dimensional matches of a coordinate or coordinates in
a set of catalog coordinates.
This finds the 3-dimensional closest neighbor, which is only different
from the on-sky distance if ``distance`` is set in either ``matchcoord``
or ``catalogcoord``.
Parameters
----------
matchcoord : `~astropy.coordinates.BaseCoordinateFrame` or `~astropy.coordinates.SkyCoord`
The coordinate(s) to match to the catalog.
catalogcoord : `~astropy.coordinates.BaseCoordinateFrame` or `~astropy.coordinates.SkyCoord`
The base catalog in which to search for matches. Typically this will
be a coordinate object that is an array (i.e.,
``catalogcoord.isscalar == False``)
nthneighbor : int, optional
Which closest neighbor to search for. Typically ``1`` is desired here,
as that is correct for matching one set of coordinates to another.
The next likely use case is ``2``, for matching a coordinate catalog
against *itself* (``1`` is inappropriate because each point will find
itself as the closest match).
storekdtree : bool or str, optional
If a string, will store the KD-Tree used for the computation
in the ``catalogcoord``, as in ``catalogcoord.cache`` with the
provided name. This dramatically speeds up subsequent calls with the
same catalog. If False, the KD-Tree is discarded after use.
Returns
-------
idx : integer array
Indices into ``catalogcoord`` to get the matched points for each
``matchcoord``. Shape matches ``matchcoord``.
sep2d : `~astropy.coordinates.Angle`
The on-sky separation between the closest match for each ``matchcoord``
and the ``matchcoord``. Shape matches ``matchcoord``.
dist3d : `~astropy.units.Quantity`
The 3D distance between the closest match for each ``matchcoord`` and
the ``matchcoord``. Shape matches ``matchcoord``.
Notes
-----
This function requires `SciPy <https://www.scipy.org/>`_ to be installed
or it will fail.
"""
if catalogcoord.isscalar or len(catalogcoord) < 1:
raise ValueError('The catalog for coordinate matching cannot be a '
'scalar or length-0.')
kdt = _get_cartesian_kdtree(catalogcoord, storekdtree)
# make sure coordinate systems match
matchcoord = matchcoord.transform_to(catalogcoord)
# make sure units match
catunit = catalogcoord.cartesian.x.unit
matchxyz = matchcoord.cartesian.xyz.to(catunit)
matchflatxyz = matchxyz.reshape((3, np.prod(matchxyz.shape) // 3))
dist, idx = kdt.query(matchflatxyz.T, nthneighbor)
if nthneighbor > 1: # query gives 1D arrays if k=1, 2D arrays otherwise
dist = dist[:, -1]
idx = idx[:, -1]
sep2d = catalogcoord[idx].separation(matchcoord)
return idx.reshape(matchxyz.shape[1:]), sep2d, dist.reshape(matchxyz.shape[1:]) * catunit
def match_coordinates_sky(matchcoord, catalogcoord, nthneighbor=1, storekdtree='kdtree_sky'):
"""
Finds the nearest on-sky matches of a coordinate or coordinates in
a set of catalog coordinates.
This finds the on-sky closest neighbor, which is only different from the
3-dimensional match if ``distance`` is set in either ``matchcoord``
or ``catalogcoord``.
Parameters
----------
matchcoord : `~astropy.coordinates.BaseCoordinateFrame` or `~astropy.coordinates.SkyCoord`
The coordinate(s) to match to the catalog.
catalogcoord : `~astropy.coordinates.BaseCoordinateFrame` or `~astropy.coordinates.SkyCoord`
The base catalog in which to search for matches. Typically this will
be a coordinate object that is an array (i.e.,
``catalogcoord.isscalar == False``)
nthneighbor : int, optional
Which closest neighbor to search for. Typically ``1`` is desired here,
as that is correct for matching one set of coordinates to another.
The next likely use case is ``2``, for matching a coordinate catalog
against *itself* (``1`` is inappropriate because each point will find
itself as the closest match).
storekdtree : bool or str, optional
If a string, will store the KD-Tree used for the computation
in the ``catalogcoord`` in ``catalogcoord.cache`` with the
provided name. This dramatically speeds up subsequent calls with the
same catalog. If False, the KD-Tree is discarded after use.
Returns
-------
idx : integer array
Indices into ``catalogcoord`` to get the matched points for each
``matchcoord``. Shape matches ``matchcoord``.
sep2d : `~astropy.coordinates.Angle`
The on-sky separation between the closest match for each
``matchcoord`` and the ``matchcoord``. Shape matches ``matchcoord``.
dist3d : `~astropy.units.Quantity`
The 3D distance between the closest match for each ``matchcoord`` and
the ``matchcoord``. Shape matches ``matchcoord``. If either
``matchcoord`` or ``catalogcoord`` don't have a distance, this is the 3D
distance on the unit sphere, rather than a true distance.
Notes
-----
This function requires `SciPy <https://www.scipy.org/>`_ to be installed
or it will fail.
"""
if catalogcoord.isscalar or len(catalogcoord) < 1:
raise ValueError('The catalog for coordinate matching cannot be a '
'scalar or length-0.')
# send to catalog frame
newmatch = matchcoord.transform_to(catalogcoord)
# strip out distance info
match_urepr = newmatch.data.represent_as(UnitSphericalRepresentation)
newmatch_u = newmatch.realize_frame(match_urepr)
cat_urepr = catalogcoord.data.represent_as(UnitSphericalRepresentation)
newcat_u = catalogcoord.realize_frame(cat_urepr)
# Check for a stored KD-tree on the passed-in coordinate. Normally it will
# have a distinct name from the "3D" one, so it's safe to use even though
# it's based on UnitSphericalRepresentation.
storekdtree = catalogcoord.cache.get(storekdtree, storekdtree)
idx, sep2d, sep3d = match_coordinates_3d(newmatch_u, newcat_u, nthneighbor, storekdtree)
# sep3d is *wrong* above, because the distance information was removed,
# unless one of the catalogs doesn't have a real distance
if not (isinstance(catalogcoord.data, UnitSphericalRepresentation) or
isinstance(newmatch.data, UnitSphericalRepresentation)):
sep3d = catalogcoord[idx].separation_3d(newmatch)
# update the kdtree on the actual passed-in coordinate
if isinstance(storekdtree, str):
catalogcoord.cache[storekdtree] = newcat_u.cache[storekdtree]
elif storekdtree is True:
# the old backwards-compatible name
catalogcoord.cache['kdtree'] = newcat_u.cache['kdtree']
return idx, sep2d, sep3d
def search_around_3d(coords1, coords2, distlimit, storekdtree='kdtree_3d'):
"""
Searches for pairs of points that are at least as close as a specified
distance in 3D space.
This is intended for use on coordinate objects with arrays of coordinates,
not scalars. For scalar coordinates, it is better to use the
``separation_3d`` methods.
Parameters
----------
coords1 : `~astropy.coordinates.BaseCoordinateFrame` or `~astropy.coordinates.SkyCoord`
The first set of coordinates, which will be searched for matches from
``coords2`` within ``seplimit``. Cannot be a scalar coordinate.
coords2 : `~astropy.coordinates.BaseCoordinateFrame` or `~astropy.coordinates.SkyCoord`
The second set of coordinates, which will be searched for matches from
``coords1`` within ``seplimit``. Cannot be a scalar coordinate.
distlimit : `~astropy.units.Quantity` with distance units
The physical radius to search within.
storekdtree : bool or str, optional
If a string, will store the KD-Tree used in the search with the name
``storekdtree`` in ``coords2.cache``. This speeds up subsequent calls
to this function. If False, the KD-Trees are not saved.
Returns
-------
idx1 : integer array
Indices into ``coords1`` that matches to the corresponding element of
``idx2``. Shape matches ``idx2``.
idx2 : integer array
Indices into ``coords2`` that matches to the corresponding element of
``idx1``. Shape matches ``idx1``.
sep2d : `~astropy.coordinates.Angle`
The on-sky separation between the coordinates. Shape matches ``idx1``
and ``idx2``.
dist3d : `~astropy.units.Quantity`
The 3D distance between the coordinates. Shape matches ``idx1`` and
``idx2``. The unit is that of ``coords1``.
Notes
-----
This function requires `SciPy <https://www.scipy.org/>`_ (>=0.12.0)
to be installed or it will fail.
If you are using this function to search in a catalog for matches around
specific points, the convention is for ``coords2`` to be the catalog, and
``coords1`` are the points to search around. While these operations are
mathematically the same if ``coords1`` and ``coords2`` are flipped, some of
the optimizations may work better if this convention is obeyed.
In the current implementation, the return values are always sorted in the
same order as the ``coords1`` (so ``idx1`` is in ascending order). This is
considered an implementation detail, though, so it could change in a future
release.
"""
if not distlimit.isscalar:
raise ValueError('distlimit must be a scalar in search_around_3d')
if coords1.isscalar or coords2.isscalar:
raise ValueError('One of the inputs to search_around_3d is a scalar. '
'search_around_3d is intended for use with array '
'coordinates, not scalars. Instead, use '
'``coord1.separation_3d(coord2) < distlimit`` to find '
'the coordinates near a scalar coordinate.')
if len(coords1) == 0 or len(coords2) == 0:
# Empty array input: return empty match
return (np.array([], dtype=int), np.array([], dtype=int),
Angle([], u.deg),
u.Quantity([], coords1.distance.unit))
kdt2 = _get_cartesian_kdtree(coords2, storekdtree)
cunit = coords2.cartesian.x.unit
# we convert coord1 to match coord2's frame. We do it this way
# so that if the conversion does happen, the KD tree of coord2 at least gets
# saved. (by convention, coord2 is the "catalog" if that makes sense)
coords1 = coords1.transform_to(coords2)
kdt1 = _get_cartesian_kdtree(coords1, storekdtree, forceunit=cunit)
# this is the *cartesian* 3D distance that corresponds to the given angle
d = distlimit.to_value(cunit)
idxs1 = []
idxs2 = []
for i, matches in enumerate(kdt1.query_ball_tree(kdt2, d)):
for match in matches:
idxs1.append(i)
idxs2.append(match)
idxs1 = np.array(idxs1, dtype=int)
idxs2 = np.array(idxs2, dtype=int)
if idxs1.size == 0:
d2ds = Angle([], u.deg)
d3ds = u.Quantity([], coords1.distance.unit)
else:
d2ds = coords1[idxs1].separation(coords2[idxs2])
d3ds = coords1[idxs1].separation_3d(coords2[idxs2])
return idxs1, idxs2, d2ds, d3ds
def search_around_sky(coords1, coords2, seplimit, storekdtree='kdtree_sky'):
"""
Searches for pairs of points that have an angular separation at least as
close as a specified angle.
This is intended for use on coordinate objects with arrays of coordinates,
not scalars. For scalar coordinates, it is better to use the ``separation``
methods.
Parameters
----------
coords1 : `~astropy.coordinates.BaseCoordinateFrame` or `~astropy.coordinates.SkyCoord`
The first set of coordinates, which will be searched for matches from
``coords2`` within ``seplimit``. Cannot be a scalar coordinate.
coords2 : `~astropy.coordinates.BaseCoordinateFrame` or `~astropy.coordinates.SkyCoord`
The second set of coordinates, which will be searched for matches from
``coords1`` within ``seplimit``. Cannot be a scalar coordinate.
seplimit : `~astropy.units.Quantity` with angle units
The on-sky separation to search within.
storekdtree : bool or str, optional
If a string, will store the KD-Tree used in the search with the name
``storekdtree`` in ``coords2.cache``. This speeds up subsequent calls
to this function. If False, the KD-Trees are not saved.
Returns
-------
idx1 : integer array
Indices into ``coords1`` that matches to the corresponding element of
``idx2``. Shape matches ``idx2``.
idx2 : integer array
Indices into ``coords2`` that matches to the corresponding element of
``idx1``. Shape matches ``idx1``.
sep2d : `~astropy.coordinates.Angle`
The on-sky separation between the coordinates. Shape matches ``idx1``
and ``idx2``.
dist3d : `~astropy.units.Quantity`
The 3D distance between the coordinates. Shape matches ``idx1``
and ``idx2``; the unit is that of ``coords1``.
If either ``coords1`` or ``coords2`` don't have a distance,
this is the 3D distance on the unit sphere, rather than a
physical distance.
Notes
-----
This function requires `SciPy <https://www.scipy.org/>`_ (>=0.12.0)
to be installed or it will fail.
In the current implementation, the return values are always sorted in the
same order as the ``coords1`` (so ``idx1`` is in ascending order). This is
considered an implementation detail, though, so it could change in a future
release.
"""
if not seplimit.isscalar:
raise ValueError('seplimit must be a scalar in search_around_sky')
if coords1.isscalar or coords2.isscalar:
raise ValueError('One of the inputs to search_around_sky is a scalar. '
'search_around_sky is intended for use with array '
'coordinates, not scalars. Instead, use '
'``coord1.separation(coord2) < seplimit`` to find the '
'coordinates near a scalar coordinate.')
if len(coords1) == 0 or len(coords2) == 0:
# Empty array input: return empty match
if coords2.distance.unit == u.dimensionless_unscaled:
distunit = u.dimensionless_unscaled
else:
distunit = coords1.distance.unit
return (np.array([], dtype=int), np.array([], dtype=int),
Angle([], u.deg),
u.Quantity([], distunit))
# we convert coord1 to match coord2's frame. We do it this way
# so that if the conversion does happen, the KD tree of coord2 at least gets
# saved. (by convention, coord2 is the "catalog" if that makes sense)
coords1 = coords1.transform_to(coords2)
# strip out distance info
urepr1 = coords1.data.represent_as(UnitSphericalRepresentation)
ucoords1 = coords1.realize_frame(urepr1)
kdt1 = _get_cartesian_kdtree(ucoords1, storekdtree)
if storekdtree and coords2.cache.get(storekdtree):
# just use the stored KD-Tree
kdt2 = coords2.cache[storekdtree]
else:
# strip out distance info
urepr2 = coords2.data.represent_as(UnitSphericalRepresentation)
ucoords2 = coords2.realize_frame(urepr2)
kdt2 = _get_cartesian_kdtree(ucoords2, storekdtree)
if storekdtree:
# save the KD-Tree in coords2, *not* ucoords2
coords2.cache['kdtree' if storekdtree is True else storekdtree] = kdt2
# this is the *cartesian* 3D distance that corresponds to the given angle
r = (2 * np.sin(Angle(seplimit) / 2.0)).value
idxs1 = []
idxs2 = []
for i, matches in enumerate(kdt1.query_ball_tree(kdt2, r)):
for match in matches:
idxs1.append(i)
idxs2.append(match)
idxs1 = np.array(idxs1, dtype=int)
idxs2 = np.array(idxs2, dtype=int)
if idxs1.size == 0:
if coords2.distance.unit == u.dimensionless_unscaled:
distunit = u.dimensionless_unscaled
else:
distunit = coords1.distance.unit
d2ds = Angle([], u.deg)
d3ds = u.Quantity([], distunit)
else:
d2ds = coords1[idxs1].separation(coords2[idxs2])
try:
d3ds = coords1[idxs1].separation_3d(coords2[idxs2])
except ValueError:
# they don't have distances, so we just fall back on the cartesian
# distance, computed from d2ds
d3ds = 2 * np.sin(d2ds / 2.0)
return idxs1, idxs2, d2ds, d3ds
def _get_cartesian_kdtree(coord, attrname_or_kdt='kdtree', forceunit=None):
"""
This is a utility function to retrieve (and build/cache, if necessary)
a 3D cartesian KD-Tree from various sorts of astropy coordinate objects.
Parameters
----------
coord : `~astropy.coordinates.BaseCoordinateFrame` or `~astropy.coordinates.SkyCoord`
The coordinates to build the KD-Tree for.
attrname_or_kdt : bool or str or KDTree
If a string, will store the KD-Tree used for the computation in the
``coord``, in ``coord.cache`` with the provided name. If given as a
KD-Tree, it will just be used directly.
forceunit : unit or None
If a unit, the cartesian coordinates will convert to that unit before
being put in the KD-Tree. If None, whatever unit it's already in
will be used
Returns
-------
kdt : `~scipy.spatial.cKDTree` or `~scipy.spatial.KDTree`
The KD-Tree representing the 3D cartesian representation of the input
coordinates.
"""
from warnings import warn
# without scipy this will immediately fail
from scipy import spatial
try:
KDTree = spatial.cKDTree
except Exception:
warn('C-based KD tree not found, falling back on (much slower) '
'python implementation')
KDTree = spatial.KDTree
if attrname_or_kdt is True: # backwards compatibility for pre v0.4
attrname_or_kdt = 'kdtree'
# figure out where any cached KDTree might be
if isinstance(attrname_or_kdt, str):
kdt = coord.cache.get(attrname_or_kdt, None)
if kdt is not None and not isinstance(kdt, KDTree):
raise TypeError('The `attrname_or_kdt` "{0}" is not a scipy KD tree!'.format(attrname_or_kdt))
elif isinstance(attrname_or_kdt, KDTree):
kdt = attrname_or_kdt
attrname_or_kdt = None
elif not attrname_or_kdt:
kdt = None
else:
raise TypeError('Invalid `attrname_or_kdt` argument for KD-Tree:' +
str(attrname_or_kdt))
if kdt is None:
# need to build the cartesian KD-tree for the catalog
if forceunit is None:
cartxyz = coord.cartesian.xyz
else:
cartxyz = coord.cartesian.xyz.to(forceunit)
flatxyz = cartxyz.reshape((3, np.prod(cartxyz.shape) // 3))
kdt = KDTree(flatxyz.value.T)
if attrname_or_kdt:
# cache the kdtree in `coord`
coord.cache[attrname_or_kdt] = kdt
return kdt
|
3dcb5ca4341829e4859d1daa2f1dc755c63f0183514e5031e9fed841a2118fc6 |
import re
import copy
import warnings
import collections
import numpy as np
from .. import _erfa as erfa
from ..utils.compat.misc import override__dir__
from ..units import Unit, IrreducibleUnit
from .. import units as u
from ..constants import c as speed_of_light
from ..wcs.utils import skycoord_to_pixel, pixel_to_skycoord
from ..utils.exceptions import AstropyDeprecationWarning
from ..utils.data_info import MixinInfo
from ..utils import ShapedLikeNDArray
from ..time import Time
from .distances import Distance
from .angles import Angle
from .baseframe import (BaseCoordinateFrame, frame_transform_graph,
GenericFrame, _get_repr_cls, _get_diff_cls,
_normalize_representation_type)
from .builtin_frames import ICRS, SkyOffsetFrame
from .representation import (BaseRepresentation, SphericalRepresentation,
UnitSphericalRepresentation, SphericalDifferential)
__all__ = ['SkyCoord', 'SkyCoordInfo']
PLUS_MINUS_RE = re.compile(r'(\+|\-)')
J_PREFIXED_RA_DEC_RE = re.compile(
r"""J # J prefix
([0-9]{6,7}\.?[0-9]{0,2}) # RA as HHMMSS.ss or DDDMMSS.ss, optional decimal digits
([\+\-][0-9]{6}\.?[0-9]{0,2})\s*$ # Dec as DDMMSS.ss, optional decimal digits
""", re.VERBOSE)
class SkyCoordInfo(MixinInfo):
"""
Container for meta information like name, description, format. This is
required when the object is used as a mixin column within a table, but can
be used as a general way to store meta information.
"""
attrs_from_parent = set(['unit']) # Unit is read-only
_supports_indexing = False
@staticmethod
def default_format(val):
repr_data = val.info._repr_data
formats = ['{0.' + compname + '.value:}' for compname
in repr_data.components]
return ','.join(formats).format(repr_data)
@property
def unit(self):
repr_data = self._repr_data
unit = ','.join(str(getattr(repr_data, comp).unit) or 'None'
for comp in repr_data.components)
return unit
@property
def _repr_data(self):
if self._parent is None:
return None
sc = self._parent
if (issubclass(sc.representation_type, SphericalRepresentation) and
isinstance(sc.data, UnitSphericalRepresentation)):
repr_data = sc.represent_as(sc.data.__class__, in_frame_units=True)
else:
repr_data = sc.represent_as(sc.representation_type,
in_frame_units=True)
return repr_data
def _represent_as_dict(self):
obj = self._parent
attrs = (list(obj.representation_component_names) +
list(frame_transform_graph.frame_attributes.keys()))
# Don't output distance if it is all unitless 1.0
if 'distance' in attrs and np.all(obj.distance == 1.0):
attrs.remove('distance')
self._represent_as_dict_attrs = attrs
out = super()._represent_as_dict()
out['representation_type'] = obj.representation_type.get_name()
out['frame'] = obj.frame.name
# Note that obj.info.unit is a fake composite unit (e.g. 'deg,deg,None'
# or None,None,m) and is not stored. The individual attributes have
# units.
return out
class SkyCoord(ShapedLikeNDArray):
"""High-level object providing a flexible interface for celestial coordinate
representation, manipulation, and transformation between systems.
The `SkyCoord` class accepts a wide variety of inputs for initialization. At
a minimum these must provide one or more celestial coordinate values with
unambiguous units. Inputs may be scalars or lists/tuples/arrays, yielding
scalar or array coordinates (can be checked via ``SkyCoord.isscalar``).
Typically one also specifies the coordinate frame, though this is not
required. The general pattern for spherical representations is::
SkyCoord(COORD, [FRAME], keyword_args ...)
SkyCoord(LON, LAT, [FRAME], keyword_args ...)
SkyCoord(LON, LAT, [DISTANCE], frame=FRAME, unit=UNIT, keyword_args ...)
SkyCoord([FRAME], <lon_attr>=LON, <lat_attr>=LAT, keyword_args ...)
It is also possible to input coordinate values in other representations
such as cartesian or cylindrical. In this case one includes the keyword
argument ``representation_type='cartesian'`` (for example) along with data
in ``x``, ``y``, and ``z``.
Examples
--------
The examples below illustrate common ways of initializing a `SkyCoord`
object. For a complete description of the allowed syntax see the
full coordinates documentation. First some imports::
>>> from astropy.coordinates import SkyCoord # High-level coordinates
>>> from astropy.coordinates import ICRS, Galactic, FK4, FK5 # Low-level frames
>>> from astropy.coordinates import Angle, Latitude, Longitude # Angles
>>> import astropy.units as u
The coordinate values and frame specification can now be provided using
positional and keyword arguments::
>>> c = SkyCoord(10, 20, unit="deg") # defaults to ICRS frame
>>> c = SkyCoord([1, 2, 3], [-30, 45, 8], "icrs", unit="deg") # 3 coords
>>> coords = ["1:12:43.2 +1:12:43", "1 12 43.2 +1 12 43"]
>>> c = SkyCoord(coords, FK4, unit=(u.deg, u.hourangle), obstime="J1992.21")
>>> c = SkyCoord("1h12m43.2s +1d12m43s", Galactic) # Units from string
>>> c = SkyCoord("galactic", l="1h12m43.2s", b="+1d12m43s")
>>> ra = Longitude([1, 2, 3], unit=u.deg) # Could also use Angle
>>> dec = np.array([4.5, 5.2, 6.3]) * u.deg # Astropy Quantity
>>> c = SkyCoord(ra, dec, frame='icrs')
>>> c = SkyCoord(ICRS, ra=ra, dec=dec, obstime='2001-01-02T12:34:56')
>>> c = FK4(1 * u.deg, 2 * u.deg) # Uses defaults for obstime, equinox
>>> c = SkyCoord(c, obstime='J2010.11', equinox='B1965') # Override defaults
>>> c = SkyCoord(w=0, u=1, v=2, unit='kpc', frame='galactic',
... representation_type='cartesian')
>>> c = SkyCoord([ICRS(ra=1*u.deg, dec=2*u.deg), ICRS(ra=3*u.deg, dec=4*u.deg)])
Velocity components (proper motions or radial velocities) can also be
provided in a similar manner::
>>> c = SkyCoord(ra=1*u.deg, dec=2*u.deg, radial_velocity=10*u.km/u.s)
>>> c = SkyCoord(ra=1*u.deg, dec=2*u.deg, pm_ra_cosdec=2*u.mas/u.yr, pm_dec=1*u.mas/u.yr)
As shown, the frame can be a `~astropy.coordinates.BaseCoordinateFrame`
class or the corresponding string alias. The frame classes that are built in
to astropy are `ICRS`, `FK5`, `FK4`, `FK4NoETerms`, and `Galactic`.
The string aliases are simply lower-case versions of the class name, and
allow for creating a `SkyCoord` object and transforming frames without
explicitly importing the frame classes.
Parameters
----------
frame : `~astropy.coordinates.BaseCoordinateFrame` class or string, optional
Type of coordinate frame this `SkyCoord` should represent. Defaults to
to ICRS if not given or given as None.
unit : `~astropy.units.Unit`, string, or tuple of :class:`~astropy.units.Unit` or str, optional
Units for supplied ``LON`` and ``LAT`` values, respectively. If
only one unit is supplied then it applies to both ``LON`` and
``LAT``.
obstime : valid `~astropy.time.Time` initializer, optional
Time of observation
equinox : valid `~astropy.time.Time` initializer, optional
Coordinate frame equinox
representation_type : str or Representation class
Specifies the representation, e.g. 'spherical', 'cartesian', or
'cylindrical'. This affects the positional args and other keyword args
which must correspond to the given representation.
copy : bool, optional
If `True` (default), a copy of any coordinate data is made. This
argument can only be passed in as a keyword argument.
**keyword_args
Other keyword arguments as applicable for user-defined coordinate frames.
Common options include:
ra, dec : valid `~astropy.coordinates.Angle` initializer, optional
RA and Dec for frames where ``ra`` and ``dec`` are keys in the
frame's ``representation_component_names``, including `ICRS`,
`FK5`, `FK4`, and `FK4NoETerms`.
pm_ra_cosdec, pm_dec : `~astropy.units.Quantity`, optional
Proper motion components, in angle per time units.
l, b : valid `~astropy.coordinates.Angle` initializer, optional
Galactic ``l`` and ``b`` for for frames where ``l`` and ``b`` are
keys in the frame's ``representation_component_names``, including
the `Galactic` frame.
pm_l_cosb, pm_b : `~astropy.units.Quantity`, optional
Proper motion components in the `Galactic` frame, in angle per time
units.
x, y, z : float or `~astropy.units.Quantity`, optional
Cartesian coordinates values
u, v, w : float or `~astropy.units.Quantity`, optional
Cartesian coordinates values for the Galactic frame.
radial_velocity : `~astropy.units.Quantity`, optional
The component of the velocity along the line-of-sight (i.e., the
radial direction), in velocity units.
"""
# Declare that SkyCoord can be used as a Table column by defining the
# info property.
info = SkyCoordInfo()
def __init__(self, *args, copy=True, **kwargs):
# Parse the args and kwargs to assemble a sanitized and validated
# kwargs dict for initializing attributes for this object and for
# creating the internal self._sky_coord_frame object
args = list(args) # Make it mutable
kwargs = self._parse_inputs(args, kwargs)
frame = kwargs['frame']
frame_attr_names = frame.get_frame_attr_names()
# these are frame attributes set on this SkyCoord but *not* a part of
# the frame object this SkyCoord contains
self._extra_frameattr_names = set()
for attr in kwargs:
if (attr not in frame_attr_names and
attr in frame_transform_graph.frame_attributes):
# Setting it will also validate it.
setattr(self, attr, kwargs[attr])
coord_kwargs = {}
component_names = frame.representation_component_names
component_names.update(frame.get_representation_component_names('s'))
# TODO: deprecate representation, remove this in future
_normalize_representation_type(kwargs)
if 'representation_type' in kwargs:
coord_kwargs['representation_type'] = _get_repr_cls(
kwargs['representation_type'])
if 'differential_type' in kwargs:
coord_kwargs['differential_type'] = _get_diff_cls(kwargs['differential_type'])
for attr, value in kwargs.items():
if value is not None and (attr in component_names
or attr in frame_attr_names):
coord_kwargs[attr] = value
# Finally make the internal coordinate object.
self._sky_coord_frame = frame.__class__(copy=copy, **coord_kwargs)
if not self._sky_coord_frame.has_data:
raise ValueError('Cannot create a SkyCoord without data')
@property
def frame(self):
return self._sky_coord_frame
@property
def representation_type(self):
return self.frame.representation_type
@representation_type.setter
def representation_type(self, value):
self.frame.representation_type = value
# TODO: deprecate these in future
@property
def representation(self):
return self.frame.representation
@representation.setter
def representation(self, value):
self.frame.representation = value
@property
def shape(self):
return self.frame.shape
def _apply(self, method, *args, **kwargs):
"""Create a new instance, applying a method to the underlying data.
In typical usage, the method is any of the shape-changing methods for
`~numpy.ndarray` (``reshape``, ``swapaxes``, etc.), as well as those
picking particular elements (``__getitem__``, ``take``, etc.), which
are all defined in `~astropy.utils.misc.ShapedLikeNDArray`. It will be
applied to the underlying arrays in the representation (e.g., ``x``,
``y``, and ``z`` for `~astropy.coordinates.CartesianRepresentation`),
as well as to any frame attributes that have a shape, with the results
used to create a new instance.
Internally, it is also used to apply functions to the above parts
(in particular, `~numpy.broadcast_to`).
Parameters
----------
method : str or callable
If str, it is the name of a method that is applied to the internal
``components``. If callable, the function is applied.
args : tuple
Any positional arguments for ``method``.
kwargs : dict
Any keyword arguments for ``method``.
"""
def apply_method(value):
if isinstance(value, ShapedLikeNDArray):
return value._apply(method, *args, **kwargs)
else:
if callable(method):
return method(value, *args, **kwargs)
else:
return getattr(value, method)(*args, **kwargs)
# create a new but empty instance, and copy over stuff
new = super().__new__(self.__class__)
new._sky_coord_frame = self._sky_coord_frame._apply(method,
*args, **kwargs)
new._extra_frameattr_names = self._extra_frameattr_names.copy()
for attr in self._extra_frameattr_names:
value = getattr(self, attr)
if getattr(value, 'size', 1) > 1:
value = apply_method(value)
elif method == 'copy' or method == 'flatten':
# flatten should copy also for a single element array, but
# we cannot use it directly for array scalars, since it
# always returns a one-dimensional array. So, just copy.
value = copy.copy(value)
setattr(new, '_' + attr, value)
# Copy other 'info' attr only if it has actually been defined.
# See PR #3898 for further explanation and justification, along
# with Quantity.__array_finalize__
if 'info' in self.__dict__:
new.info = self.info
return new
def _parse_inputs(self, args, kwargs):
"""
Assemble a validated and sanitized keyword args dict for instantiating a
SkyCoord and coordinate object from the provided `args`, and `kwargs`.
"""
valid_kwargs = {}
# Put the SkyCoord attributes like frame, equinox, obstime, location
# into valid_kwargs dict. `Frame` could come from args or kwargs, so
# set valid_kwargs['frame'] accordingly. The others must be specified
# by keyword args or else get a None default. Pop them off of kwargs
# in the process.
frame = valid_kwargs['frame'] = _get_frame(args, kwargs)
# TODO: possibly remove the below. The representation/differential
# information should *already* be stored in the frame object, as it is
# extracted in _get_frame. So it may be redundent to include it below.
# TODO: deprecate representation, remove this in future
_normalize_representation_type(kwargs)
if 'representation_type' in kwargs:
valid_kwargs['representation_type'] = _get_repr_cls(
kwargs.pop('representation_type'))
if 'differential_type' in kwargs:
valid_kwargs['differential_type'] = _get_diff_cls(
kwargs.pop('differential_type'))
for attr in frame_transform_graph.frame_attributes:
if attr in kwargs:
valid_kwargs[attr] = kwargs.pop(attr)
# Get units
units = _get_representation_component_units(args, kwargs)
# Grab any frame-specific attr names like `ra` or `l` or `distance` from
# kwargs and migrate to valid_kwargs.
valid_kwargs.update(_get_representation_attrs(frame, units, kwargs))
# Error if anything is still left in kwargs
if kwargs:
# The next few lines add a more user-friendly error message to a
# common and confusing situation when the user specifies, e.g.,
# `pm_ra` when they really should be passing `pm_ra_cosdec`. The
# extra error should only turn on when the positional representation
# is spherical, and when the component 'pm_<lon>' is passed.
pm_message = ''
if frame.representation_type == SphericalRepresentation:
frame_names = list(frame.get_representation_component_names().keys())
lon_name = frame_names[0]
lat_name = frame_names[1]
if 'pm_{0}'.format(lon_name) in list(kwargs.keys()):
pm_message = ('\n\n By default, most frame classes expect '
'the longitudinal proper motion to include '
'the cos(latitude) term, named '
'`pm_{0}_cos{1}`. Did you mean to pass in '
'this component?'
.format(lon_name, lat_name))
raise ValueError('Unrecognized keyword argument(s) {0}{1}'
.format(', '.join("'{0}'".format(key)
for key in kwargs),
pm_message))
# Finally deal with the unnamed args. This figures out what the arg[0]
# is and returns a dict with appropriate key/values for initializing
# frame class. Note that differentials are *never* valid args, only
# kwargs. So they are not accounted for here (unless they're in a frame
# or SkyCoord object)
if args:
if len(args) == 1:
# One arg which must be a coordinate. In this case
# coord_kwargs will contain keys like 'ra', 'dec', 'distance'
# along with any frame attributes like equinox or obstime which
# were explicitly specified in the coordinate object (i.e. non-default).
coord_kwargs = _parse_coordinate_arg(args[0], frame, units, kwargs)
# Copy other 'info' attr only if it has actually been defined.
if 'info' in getattr(args[0], '__dict__', ()):
self.info = args[0].info
elif len(args) <= 3:
frame_attr_names = frame.representation_component_names.keys()
repr_attr_names = frame.representation_component_names.values()
coord_kwargs = {}
for arg, frame_attr_name, repr_attr_name, unit in zip(args, frame_attr_names,
repr_attr_names, units):
attr_class = frame.representation.attr_classes[repr_attr_name]
coord_kwargs[frame_attr_name] = attr_class(arg, unit=unit)
else:
raise ValueError('Must supply no more than three positional arguments, got {}'
.format(len(args)))
# Copy the coord_kwargs into the final valid_kwargs dict. For each
# of the coord_kwargs ensure that there is no conflict with a value
# specified by the user in the original kwargs.
for attr, coord_value in coord_kwargs.items():
if (attr in valid_kwargs
and valid_kwargs[attr] is not None
and np.any(valid_kwargs[attr] != coord_value)):
raise ValueError("Coordinate attribute '{0}'={1!r} conflicts with "
"keyword argument '{0}'={2!r}"
.format(attr, coord_value, valid_kwargs[attr]))
valid_kwargs[attr] = coord_value
return valid_kwargs
def transform_to(self, frame, merge_attributes=True):
"""Transform this coordinate to a new frame.
The precise frame transformed to depends on ``merge_attributes``.
If `False`, the destination frame is used exactly as passed in.
But this is often not quite what one wants. E.g., suppose one wants to
transform an ICRS coordinate that has an obstime attribute to FK4; in
this case, one likely would want to use this information. Thus, the
default for ``merge_attributes`` is `True`, in which the precedence is
as follows: (1) explicitly set (i.e., non-default) values in the
destination frame; (2) explicitly set values in the source; (3) default
value in the destination frame.
Note that in either case, any explicitly set attributes on the source
`SkyCoord` that are not part of the destination frame's definition are
kept (stored on the resulting `SkyCoord`), and thus one can round-trip
(e.g., from FK4 to ICRS to FK4 without loosing obstime).
Parameters
----------
frame : str, `BaseCoordinateFrame` class or instance, or `SkyCoord` instance
The frame to transform this coordinate into. If a `SkyCoord`, the
underlying frame is extracted, and all other information ignored.
merge_attributes : bool, optional
Whether the default attributes in the destination frame are allowed
to be overridden by explicitly set attributes in the source
(see note above; default: `True`).
Returns
-------
coord : `SkyCoord`
A new object with this coordinate represented in the `frame` frame.
Raises
------
ValueError
If there is no possible transformation route.
"""
from astropy.coordinates.errors import ConvertError
frame_kwargs = {}
# Frame name (string) or frame class? Coerce into an instance.
try:
frame = _get_frame_class(frame)()
except Exception:
pass
if isinstance(frame, SkyCoord):
frame = frame.frame # Change to underlying coord frame instance
if isinstance(frame, BaseCoordinateFrame):
new_frame_cls = frame.__class__
# Get frame attributes, allowing defaults to be overridden by
# explicitly set attributes of the source if ``merge_attributes``.
for attr in frame_transform_graph.frame_attributes:
self_val = getattr(self, attr, None)
frame_val = getattr(frame, attr, None)
if (frame_val is not None and not
(merge_attributes and frame.is_frame_attr_default(attr))):
frame_kwargs[attr] = frame_val
elif (self_val is not None and
not self.is_frame_attr_default(attr)):
frame_kwargs[attr] = self_val
elif frame_val is not None:
frame_kwargs[attr] = frame_val
else:
raise ValueError('Transform `frame` must be a frame name, class, or instance')
# Get the composite transform to the new frame
trans = frame_transform_graph.get_transform(self.frame.__class__, new_frame_cls)
if trans is None:
raise ConvertError('Cannot transform from {0} to {1}'
.format(self.frame.__class__, new_frame_cls))
# Make a generic frame which will accept all the frame kwargs that
# are provided and allow for transforming through intermediate frames
# which may require one or more of those kwargs.
generic_frame = GenericFrame(frame_kwargs)
# Do the transformation, returning a coordinate frame of the desired
# final type (not generic).
new_coord = trans(self.frame, generic_frame)
# Finally make the new SkyCoord object from the `new_coord` and
# remaining frame_kwargs that are not frame_attributes in `new_coord`.
for attr in (set(new_coord.get_frame_attr_names()) &
set(frame_kwargs.keys())):
frame_kwargs.pop(attr)
return self.__class__(new_coord, **frame_kwargs)
def apply_space_motion(self, new_obstime=None, dt=None):
"""
Compute the position of the source represented by this coordinate object
to a new time using the velocities stored in this object and assuming
linear space motion (including relativistic corrections). This is
sometimes referred to as an "epoch transformation."
The initial time before the evolution is taken from the ``obstime``
attribute of this coordinate. Note that this method currently does not
support evolving coordinates where the *frame* has an ``obstime`` frame
attribute, so the ``obstime`` is only used for storing the before and
after times, not actually as an attribute of the frame. Alternatively,
if ``dt`` is given, an ``obstime`` need not be provided at all.
Parameters
----------
new_obstime : `~astropy.time.Time`, optional
The time at which to evolve the position to. Requires that the
``obstime`` attribute be present on this frame.
dt : `~astropy.units.Quantity`, `~astropy.time.TimeDelta`, optional
An amount of time to evolve the position of the source. Cannot be
given at the same time as ``new_obstime``.
Returns
-------
new_coord : `SkyCoord`
A new coordinate object with the evolved location of this coordinate
at the new time. ``obstime`` will be set on this object to the new
time only if ``self`` also has ``obstime``.
"""
if (new_obstime is None and dt is None or
new_obstime is not None and dt is not None):
raise ValueError("You must specify one of `new_obstime` or `dt`, "
"but not both.")
# Validate that we have velocity info
if 's' not in self.frame.data.differentials:
raise ValueError('SkyCoord requires velocity data to evolve the '
'position.')
if 'obstime' in self.frame.frame_attributes:
raise NotImplementedError("Updating the coordinates in a frame "
"with explicit time dependence is "
"currently not supported. If you would "
"like this functionality, please open an "
"issue on github:\n"
"https://github.com/astropy/astropy")
if new_obstime is not None and self.obstime is None:
# If no obstime is already on this object, raise an error if a new
# obstime is passed: we need to know the time / epoch at which the
# the position / velocity were measured initially
raise ValueError('This object has no associated `obstime`. '
'apply_space_motion() must receive a time '
'difference, `dt`, and not a new obstime.')
# Compute t1 and t2, the times used in the starpm call, which *only*
# uses them to compute a delta-time
t1 = self.obstime
if dt is None:
# self.obstime is not None and new_obstime is not None b/c of above
# checks
t2 = new_obstime
else:
# new_obstime is definitely None b/c of the above checks
if t1 is None:
# MAGIC NUMBER: if the current SkyCoord object has no obstime,
# assume J2000 to do the dt offset. This is not actually used
# for anything except a delta-t in starpm, so it's OK that it's
# not necessarily the "real" obstime
t1 = Time('J2000')
new_obstime = None # we don't actually know the inital obstime
t2 = t1 + dt
else:
t2 = t1 + dt
new_obstime = t2
# starpm wants tdb time
t1 = t1.tdb
t2 = t2.tdb
# proper motion in RA should not include the cos(dec) term, see the
# erfa function eraStarpv, comment (4). So we convert to the regular
# spherical differentials.
icrsrep = self.icrs.represent_as(SphericalRepresentation, SphericalDifferential)
icrsvel = icrsrep.differentials['s']
try:
plx = icrsrep.distance.to_value(u.arcsecond, u.parallax())
except u.UnitConversionError: # No distance: set to 0 by starpm convention
plx = 0.
try:
rv = icrsvel.d_distance.to_value(u.km/u.s)
except u.UnitConversionError: # No RV
rv = 0.
starpm = erfa.starpm(icrsrep.lon.radian, icrsrep.lat.radian,
icrsvel.d_lon.to_value(u.radian/u.yr),
icrsvel.d_lat.to_value(u.radian/u.yr),
plx, rv, t1.jd1, t1.jd2, t2.jd1, t2.jd2)
icrs2 = ICRS(ra=u.Quantity(starpm[0], u.radian, copy=False),
dec=u.Quantity(starpm[1], u.radian, copy=False),
pm_ra=u.Quantity(starpm[2], u.radian/u.yr, copy=False),
pm_dec=u.Quantity(starpm[3], u.radian/u.yr, copy=False),
distance=Distance(parallax=starpm[4] * u.arcsec, copy=False),
radial_velocity=u.Quantity(starpm[5], u.km/u.s, copy=False),
differential_type=SphericalDifferential)
# Update the obstime of the returned SkyCoord, and need to carry along
# the frame attributes
frattrs = {attrnm: getattr(self, attrnm)
for attrnm in self._extra_frameattr_names}
frattrs['obstime'] = new_obstime
return self.__class__(icrs2, **frattrs).transform_to(self.frame)
def __getattr__(self, attr):
"""
Overrides getattr to return coordinates that this can be transformed
to, based on the alias attr in the master transform graph.
"""
if '_sky_coord_frame' in self.__dict__:
if self.frame.name == attr:
return self # Should this be a deepcopy of self?
# Anything in the set of all possible frame_attr_names is handled
# here. If the attr is relevant for the current frame then delegate
# to self.frame otherwise get it from self._<attr>.
if attr in frame_transform_graph.frame_attributes:
if attr in self.frame.get_frame_attr_names():
return getattr(self.frame, attr)
else:
return getattr(self, '_' + attr, None)
# Some attributes might not fall in the above category but still
# are available through self._sky_coord_frame.
if not attr.startswith('_') and hasattr(self._sky_coord_frame, attr):
return getattr(self._sky_coord_frame, attr)
# Try to interpret as a new frame for transforming.
frame_cls = frame_transform_graph.lookup_name(attr)
if frame_cls is not None and self.frame.is_transformable_to(frame_cls):
return self.transform_to(attr)
# Fail
raise AttributeError("'{0}' object has no attribute '{1}'"
.format(self.__class__.__name__, attr))
def __setattr__(self, attr, val):
# This is to make anything available through __getattr__ immutable
if '_sky_coord_frame' in self.__dict__:
if self.frame.name == attr:
raise AttributeError("'{0}' is immutable".format(attr))
if not attr.startswith('_') and hasattr(self._sky_coord_frame, attr):
setattr(self._sky_coord_frame, attr, val)
return
frame_cls = frame_transform_graph.lookup_name(attr)
if frame_cls is not None and self.frame.is_transformable_to(frame_cls):
raise AttributeError("'{0}' is immutable".format(attr))
if attr in frame_transform_graph.frame_attributes:
# All possible frame attributes can be set, but only via a private
# variable. See __getattr__ above.
super().__setattr__('_' + attr, val)
# Validate it
frame_transform_graph.frame_attributes[attr].__get__(self)
# And add to set of extra attributes
self._extra_frameattr_names |= {attr}
else:
# Otherwise, do the standard Python attribute setting
super().__setattr__(attr, val)
def __delattr__(self, attr):
# mirror __setattr__ above
if '_sky_coord_frame' in self.__dict__:
if self.frame.name == attr:
raise AttributeError("'{0}' is immutable".format(attr))
if not attr.startswith('_') and hasattr(self._sky_coord_frame,
attr):
delattr(self._sky_coord_frame, attr)
return
frame_cls = frame_transform_graph.lookup_name(attr)
if frame_cls is not None and self.frame.is_transformable_to(frame_cls):
raise AttributeError("'{0}' is immutable".format(attr))
if attr in frame_transform_graph.frame_attributes:
# All possible frame attributes can be deleted, but need to remove
# the corresponding private variable. See __getattr__ above.
super().__delattr__('_' + attr)
# Also remove it from the set of extra attributes
self._extra_frameattr_names -= {attr}
else:
# Otherwise, do the standard Python attribute setting
super().__delattr__(attr)
@override__dir__
def __dir__(self):
"""
Override the builtin `dir` behavior to include:
- Transforms available by aliases
- Attribute / methods of the underlying self.frame object
"""
# determine the aliases that this can be transformed to.
dir_values = set()
for name in frame_transform_graph.get_names():
frame_cls = frame_transform_graph.lookup_name(name)
if self.frame.is_transformable_to(frame_cls):
dir_values.add(name)
# Add public attributes of self.frame
dir_values.update(set(attr for attr in dir(self.frame) if not attr.startswith('_')))
# Add all possible frame attributes
dir_values.update(frame_transform_graph.frame_attributes.keys())
return dir_values
def __repr__(self):
clsnm = self.__class__.__name__
coonm = self.frame.__class__.__name__
frameattrs = self.frame._frame_attrs_repr()
if frameattrs:
frameattrs = ': ' + frameattrs
data = self.frame._data_repr()
if data:
data = ': ' + data
return '<{clsnm} ({coonm}{frameattrs}){data}>'.format(**locals())
def to_string(self, style='decimal', **kwargs):
"""
A string representation of the coordinates.
The default styles definitions are::
'decimal': 'lat': {'decimal': True, 'unit': "deg"}
'lon': {'decimal': True, 'unit': "deg"}
'dms': 'lat': {'unit': "deg"}
'lon': {'unit': "deg"}
'hmsdms': 'lat': {'alwayssign': True, 'pad': True, 'unit': "deg"}
'lon': {'pad': True, 'unit': "hour"}
See :meth:`~astropy.coordinates.Angle.to_string` for details and
keyword arguments (the two angles forming the coordinates are are
both :class:`~astropy.coordinates.Angle` instances). Keyword
arguments have precedence over the style defaults and are passed
to :meth:`~astropy.coordinates.Angle.to_string`.
Parameters
----------
style : {'hmsdms', 'dms', 'decimal'}
The formatting specification to use. These encode the three most
common ways to represent coordinates. The default is `decimal`.
kwargs
Keyword args passed to :meth:`~astropy.coordinates.Angle.to_string`.
"""
sph_coord = self.frame.represent_as(SphericalRepresentation)
styles = {'hmsdms': {'lonargs': {'unit': u.hour, 'pad': True},
'latargs': {'unit': u.degree, 'pad': True, 'alwayssign': True}},
'dms': {'lonargs': {'unit': u.degree},
'latargs': {'unit': u.degree}},
'decimal': {'lonargs': {'unit': u.degree, 'decimal': True},
'latargs': {'unit': u.degree, 'decimal': True}}
}
lonargs = {}
latargs = {}
if style in styles:
lonargs.update(styles[style]['lonargs'])
latargs.update(styles[style]['latargs'])
else:
raise ValueError('Invalid style. Valid options are: {0}'.format(",".join(styles)))
lonargs.update(kwargs)
latargs.update(kwargs)
if np.isscalar(sph_coord.lon.value):
coord_string = (sph_coord.lon.to_string(**lonargs)
+ " " +
sph_coord.lat.to_string(**latargs))
else:
coord_string = []
for lonangle, latangle in zip(sph_coord.lon.ravel(), sph_coord.lat.ravel()):
coord_string += [(lonangle.to_string(**lonargs)
+ " " +
latangle.to_string(**latargs))]
if len(sph_coord.shape) > 1:
coord_string = np.array(coord_string).reshape(sph_coord.shape)
return coord_string
def is_equivalent_frame(self, other):
"""
Checks if this object's frame as the same as that of the ``other``
object.
To be the same frame, two objects must be the same frame class and have
the same frame attributes. For two `SkyCoord` objects, *all* of the
frame attributes have to match, not just those relevant for the object's
frame.
Parameters
----------
other : SkyCoord or BaseCoordinateFrame
The other object to check.
Returns
-------
isequiv : bool
True if the frames are the same, False if not.
Raises
------
TypeError
If ``other`` isn't a `SkyCoord` or a `BaseCoordinateFrame` or subclass.
"""
if isinstance(other, BaseCoordinateFrame):
return self.frame.is_equivalent_frame(other)
elif isinstance(other, SkyCoord):
if other.frame.name != self.frame.name:
return False
for fattrnm in frame_transform_graph.frame_attributes:
if np.any(getattr(self, fattrnm) != getattr(other, fattrnm)):
return False
return True
else:
# not a BaseCoordinateFrame nor a SkyCoord object
raise TypeError("Tried to do is_equivalent_frame on something that "
"isn't frame-like")
# High-level convenience methods
def separation(self, other):
"""
Computes on-sky separation between this coordinate and another.
.. note::
If the ``other`` coordinate object is in a different frame, it is
first transformed to the frame of this object. This can lead to
unintutive behavior if not accounted for. Particularly of note is
that ``self.separation(other)`` and ``other.separation(self)`` may
not give the same answer in this case.
For more on how to use this (and related) functionality, see the
examples in :doc:`/coordinates/matchsep`.
Parameters
----------
other : `~astropy.coordinates.SkyCoord` or `~astropy.coordinates.BaseCoordinateFrame`
The coordinate to get the separation to.
Returns
-------
sep : `~astropy.coordinates.Angle`
The on-sky separation between this and the ``other`` coordinate.
Notes
-----
The separation is calculated using the Vincenty formula, which
is stable at all locations, including poles and antipodes [1]_.
.. [1] https://en.wikipedia.org/wiki/Great-circle_distance
"""
from . import Angle
from .angle_utilities import angular_separation
if not self.is_equivalent_frame(other):
try:
other = other.transform_to(self, merge_attributes=False)
except TypeError:
raise TypeError('Can only get separation to another SkyCoord '
'or a coordinate frame with data')
lon1 = self.spherical.lon
lat1 = self.spherical.lat
lon2 = other.spherical.lon
lat2 = other.spherical.lat
# Get the separation as a Quantity, convert to Angle in degrees
sep = angular_separation(lon1, lat1, lon2, lat2)
return Angle(sep, unit=u.degree)
def separation_3d(self, other):
"""
Computes three dimensional separation between this coordinate
and another.
For more on how to use this (and related) functionality, see the
examples in :doc:`/coordinates/matchsep`.
Parameters
----------
other : `~astropy.coordinates.SkyCoord` or `~astropy.coordinates.BaseCoordinateFrame`
The coordinate to get the separation to.
Returns
-------
sep : `~astropy.coordinates.Distance`
The real-space distance between these two coordinates.
Raises
------
ValueError
If this or the other coordinate do not have distances.
"""
if not self.is_equivalent_frame(other):
try:
other = other.transform_to(self, merge_attributes=False)
except TypeError:
raise TypeError('Can only get separation to another SkyCoord '
'or a coordinate frame with data')
if issubclass(self.data.__class__, UnitSphericalRepresentation):
raise ValueError('This object does not have a distance; cannot '
'compute 3d separation.')
if issubclass(other.data.__class__, UnitSphericalRepresentation):
raise ValueError('The other object does not have a distance; '
'cannot compute 3d separation.')
return Distance((self.cartesian - other.cartesian).norm())
def spherical_offsets_to(self, tocoord):
r"""
Computes angular offsets to go *from* this coordinate *to* another.
Parameters
----------
tocoord : `~astropy.coordinates.BaseCoordinateFrame`
The coordinate to offset to.
Returns
-------
lon_offset : `~astropy.coordinates.Angle`
The angular offset in the longitude direction (i.e., RA for
equatorial coordinates).
lat_offset : `~astropy.coordinates.Angle`
The angular offset in the latitude direction (i.e., Dec for
equatorial coordinates).
Raises
------
ValueError
If the ``tocoord`` is not in the same frame as this one. This is
different from the behavior of the `separation`/`separation_3d`
methods because the offset components depend critically on the
specific choice of frame.
Notes
-----
This uses the sky offset frame machinery, and hence will produce a new
sky offset frame if one does not already exist for this object's frame
class.
See Also
--------
separation : for the *total* angular offset (not broken out into components)
"""
if not self.is_equivalent_frame(tocoord):
raise ValueError('Tried to use spherical_offsets_to with two non-matching frames!')
aframe = self.skyoffset_frame()
acoord = tocoord.transform_to(aframe)
dlon = acoord.spherical.lon.view(Angle)
dlat = acoord.spherical.lat.view(Angle)
return dlon, dlat
def match_to_catalog_sky(self, catalogcoord, nthneighbor=1):
"""
Finds the nearest on-sky matches of this coordinate in a set of
catalog coordinates.
For more on how to use this (and related) functionality, see the
examples in :doc:`/coordinates/matchsep`.
Parameters
----------
catalogcoord : `~astropy.coordinates.SkyCoord` or `~astropy.coordinates.BaseCoordinateFrame`
The base catalog in which to search for matches. Typically this
will be a coordinate object that is an array (i.e.,
``catalogcoord.isscalar == False``)
nthneighbor : int, optional
Which closest neighbor to search for. Typically ``1`` is
desired here, as that is correct for matching one set of
coordinates to another. The next likely use case is ``2``,
for matching a coordinate catalog against *itself* (``1``
is inappropriate because each point will find itself as the
closest match).
Returns
-------
idx : integer array
Indices into ``catalogcoord`` to get the matched points for
each of this object's coordinates. Shape matches this
object.
sep2d : `~astropy.coordinates.Angle`
The on-sky separation between the closest match for each
element in this object in ``catalogcoord``. Shape matches
this object.
dist3d : `~astropy.units.Quantity`
The 3D distance between the closest match for each element
in this object in ``catalogcoord``. Shape matches this
object. Unless both this and ``catalogcoord`` have associated
distances, this quantity assumes that all sources are at a
distance of 1 (dimensionless).
Notes
-----
This method requires `SciPy <https://www.scipy.org/>`_ to be
installed or it will fail.
See Also
--------
astropy.coordinates.match_coordinates_sky
SkyCoord.match_to_catalog_3d
"""
from .matching import match_coordinates_sky
if (isinstance(catalogcoord, (SkyCoord, BaseCoordinateFrame))
and catalogcoord.has_data):
self_in_catalog_frame = self.transform_to(catalogcoord)
else:
raise TypeError('Can only get separation to another SkyCoord or a '
'coordinate frame with data')
res = match_coordinates_sky(self_in_catalog_frame, catalogcoord,
nthneighbor=nthneighbor,
storekdtree='_kdtree_sky')
return res
def match_to_catalog_3d(self, catalogcoord, nthneighbor=1):
"""
Finds the nearest 3-dimensional matches of this coordinate to a set
of catalog coordinates.
This finds the 3-dimensional closest neighbor, which is only different
from the on-sky distance if ``distance`` is set in this object or the
``catalogcoord`` object.
For more on how to use this (and related) functionality, see the
examples in :doc:`/coordinates/matchsep`.
Parameters
----------
catalogcoord : `~astropy.coordinates.SkyCoord` or `~astropy.coordinates.BaseCoordinateFrame`
The base catalog in which to search for matches. Typically this
will be a coordinate object that is an array (i.e.,
``catalogcoord.isscalar == False``)
nthneighbor : int, optional
Which closest neighbor to search for. Typically ``1`` is
desired here, as that is correct for matching one set of
coordinates to another. The next likely use case is
``2``, for matching a coordinate catalog against *itself*
(``1`` is inappropriate because each point will find
itself as the closest match).
Returns
-------
idx : integer array
Indices into ``catalogcoord`` to get the matched points for
each of this object's coordinates. Shape matches this
object.
sep2d : `~astropy.coordinates.Angle`
The on-sky separation between the closest match for each
element in this object in ``catalogcoord``. Shape matches
this object.
dist3d : `~astropy.units.Quantity`
The 3D distance between the closest match for each element
in this object in ``catalogcoord``. Shape matches this
object.
Notes
-----
This method requires `SciPy <https://www.scipy.org/>`_ to be
installed or it will fail.
See Also
--------
astropy.coordinates.match_coordinates_3d
SkyCoord.match_to_catalog_sky
"""
from .matching import match_coordinates_3d
if (isinstance(catalogcoord, (SkyCoord, BaseCoordinateFrame))
and catalogcoord.has_data):
self_in_catalog_frame = self.transform_to(catalogcoord)
else:
raise TypeError('Can only get separation to another SkyCoord or a '
'coordinate frame with data')
res = match_coordinates_3d(self_in_catalog_frame, catalogcoord,
nthneighbor=nthneighbor,
storekdtree='_kdtree_3d')
return res
def search_around_sky(self, searcharoundcoords, seplimit):
"""
Searches for all coordinates in this object around a supplied set of
points within a given on-sky separation.
This is intended for use on `~astropy.coordinates.SkyCoord` objects
with coordinate arrays, rather than a scalar coordinate. For a scalar
coordinate, it is better to use
`~astropy.coordinates.SkyCoord.separation`.
For more on how to use this (and related) functionality, see the
examples in :doc:`/coordinates/matchsep`.
Parameters
----------
searcharoundcoords : `~astropy.coordinates.SkyCoord` or `~astropy.coordinates.BaseCoordinateFrame`
The coordinates to search around to try to find matching points in
this `SkyCoord`. This should be an object with array coordinates,
not a scalar coordinate object.
seplimit : `~astropy.units.Quantity` with angle units
The on-sky separation to search within.
Returns
-------
idxsearcharound : integer array
Indices into ``self`` that matches to the corresponding element of
``idxself``. Shape matches ``idxself``.
idxself : integer array
Indices into ``searcharoundcoords`` that matches to the
corresponding element of ``idxsearcharound``. Shape matches
``idxsearcharound``.
sep2d : `~astropy.coordinates.Angle`
The on-sky separation between the coordinates. Shape matches
``idxsearcharound`` and ``idxself``.
dist3d : `~astropy.units.Quantity`
The 3D distance between the coordinates. Shape matches
``idxsearcharound`` and ``idxself``.
Notes
-----
This method requires `SciPy <https://www.scipy.org/>`_ (>=0.12.0) to be
installed or it will fail.
In the current implementation, the return values are always sorted in
the same order as the ``searcharoundcoords`` (so ``idxsearcharound`` is
in ascending order). This is considered an implementation detail,
though, so it could change in a future release.
See Also
--------
astropy.coordinates.search_around_sky
SkyCoord.search_around_3d
"""
from .matching import search_around_sky
return search_around_sky(searcharoundcoords, self, seplimit,
storekdtree='_kdtree_sky')
def search_around_3d(self, searcharoundcoords, distlimit):
"""
Searches for all coordinates in this object around a supplied set of
points within a given 3D radius.
This is intended for use on `~astropy.coordinates.SkyCoord` objects
with coordinate arrays, rather than a scalar coordinate. For a scalar
coordinate, it is better to use
`~astropy.coordinates.SkyCoord.separation_3d`.
For more on how to use this (and related) functionality, see the
examples in :doc:`/coordinates/matchsep`.
Parameters
----------
searcharoundcoords : `~astropy.coordinates.SkyCoord` or `~astropy.coordinates.BaseCoordinateFrame`
The coordinates to search around to try to find matching points in
this `SkyCoord`. This should be an object with array coordinates,
not a scalar coordinate object.
distlimit : `~astropy.units.Quantity` with distance units
The physical radius to search within.
Returns
-------
idxsearcharound : integer array
Indices into ``self`` that matches to the corresponding element of
``idxself``. Shape matches ``idxself``.
idxself : integer array
Indices into ``searcharoundcoords`` that matches to the
corresponding element of ``idxsearcharound``. Shape matches
``idxsearcharound``.
sep2d : `~astropy.coordinates.Angle`
The on-sky separation between the coordinates. Shape matches
``idxsearcharound`` and ``idxself``.
dist3d : `~astropy.units.Quantity`
The 3D distance between the coordinates. Shape matches
``idxsearcharound`` and ``idxself``.
Notes
-----
This method requires `SciPy <https://www.scipy.org/>`_ (>=0.12.0) to be
installed or it will fail.
In the current implementation, the return values are always sorted in
the same order as the ``searcharoundcoords`` (so ``idxsearcharound`` is
in ascending order). This is considered an implementation detail,
though, so it could change in a future release.
See Also
--------
astropy.coordinates.search_around_3d
SkyCoord.search_around_sky
"""
from .matching import search_around_3d
return search_around_3d(searcharoundcoords, self, distlimit,
storekdtree='_kdtree_3d')
def position_angle(self, other):
"""
Computes the on-sky position angle (East of North) between this
`SkyCoord` and another.
Parameters
----------
other : `SkyCoord`
The other coordinate to compute the position angle to. It is
treated as the "head" of the vector of the position angle.
Returns
-------
pa : `~astropy.coordinates.Angle`
The (positive) position angle of the vector pointing from ``self``
to ``other``. If either ``self`` or ``other`` contain arrays, this
will be an array following the appropriate `numpy` broadcasting
rules.
Examples
--------
>>> c1 = SkyCoord(0*u.deg, 0*u.deg)
>>> c2 = SkyCoord(1*u.deg, 0*u.deg)
>>> c1.position_angle(c2).degree
90.0
>>> c3 = SkyCoord(1*u.deg, 1*u.deg)
>>> c1.position_angle(c3).degree # doctest: +FLOAT_CMP
44.995636455344844
"""
from . import angle_utilities
if not self.is_equivalent_frame(other):
try:
other = other.transform_to(self, merge_attributes=False)
except TypeError:
raise TypeError('Can only get position_angle to another '
'SkyCoord or a coordinate frame with data')
slat = self.represent_as(UnitSphericalRepresentation).lat
slon = self.represent_as(UnitSphericalRepresentation).lon
olat = other.represent_as(UnitSphericalRepresentation).lat
olon = other.represent_as(UnitSphericalRepresentation).lon
return angle_utilities.position_angle(slon, slat, olon, olat)
def skyoffset_frame(self, rotation=None):
"""
Returns the sky offset frame with this `SkyCoord` at the origin.
Returns
-------
astrframe : `~astropy.coordinates.SkyOffsetFrame`
A sky offset frame of the same type as this `SkyCoord` (e.g., if
this object has an ICRS coordinate, the resulting frame is
SkyOffsetICRS, with the origin set to this object)
rotation : `~astropy.coordinates.Angle` or `~astropy.units.Quantity` with angle units
The final rotation of the frame about the ``origin``. The sign of
the rotation is the left-hand rule. That is, an object at a
particular position angle in the un-rotated system will be sent to
the positive latitude (z) direction in the final frame.
"""
return SkyOffsetFrame(origin=self, rotation=rotation)
def get_constellation(self, short_name=False, constellation_list='iau'):
"""
Determines the constellation(s) of the coordinates this `SkyCoord`
contains.
Parameters
----------
short_name : bool
If True, the returned names are the IAU-sanctioned abbreviated
names. Otherwise, full names for the constellations are used.
constellation_list : str
The set of constellations to use. Currently only ``'iau'`` is
supported, meaning the 88 "modern" constellations endorsed by the IAU.
Returns
-------
constellation : str or string array
If this is a scalar coordinate, returns the name of the
constellation. If it is an array `SkyCoord`, it returns an array of
names.
Notes
-----
To determine which constellation a point on the sky is in, this first
precesses to B1875, and then uses the Delporte boundaries of the 88
modern constellations, as tabulated by
`Roman 1987 <http://cdsarc.u-strasbg.fr/viz-bin/Cat?VI/42>`_.
See Also
--------
astropy.coordinates.get_constellation
"""
from .funcs import get_constellation
# because of issue #7028, the conversion to a PrecessedGeocentric
# system fails in some cases. Work around is to drop the velocities.
# they are not needed here since only position infromation is used
extra_frameattrs = {nm: getattr(self, nm)
for nm in self._extra_frameattr_names}
novel = SkyCoord(self.realize_frame(self.data.without_differentials()),
**extra_frameattrs)
return get_constellation(novel, short_name, constellation_list)
# the simpler version below can be used when gh-issue #7028 is resolved
#return get_constellation(self, short_name, constellation_list)
# WCS pixel to/from sky conversions
def to_pixel(self, wcs, origin=0, mode='all'):
"""
Convert this coordinate to pixel coordinates using a `~astropy.wcs.WCS`
object.
Parameters
----------
wcs : `~astropy.wcs.WCS`
The WCS to use for convert
origin : int
Whether to return 0 or 1-based pixel coordinates.
mode : 'all' or 'wcs'
Whether to do the transformation including distortions (``'all'``) or
only including only the core WCS transformation (``'wcs'``).
Returns
-------
xp, yp : `numpy.ndarray`
The pixel coordinates
See Also
--------
astropy.wcs.utils.skycoord_to_pixel : the implementation of this method
"""
return skycoord_to_pixel(self, wcs=wcs, origin=origin, mode=mode)
@classmethod
def from_pixel(cls, xp, yp, wcs, origin=0, mode='all'):
"""
Create a new `SkyCoord` from pixel coordinates using an
`~astropy.wcs.WCS` object.
Parameters
----------
xp, yp : float or `numpy.ndarray`
The coordinates to convert.
wcs : `~astropy.wcs.WCS`
The WCS to use for convert
origin : int
Whether to return 0 or 1-based pixel coordinates.
mode : 'all' or 'wcs'
Whether to do the transformation including distortions (``'all'``) or
only including only the core WCS transformation (``'wcs'``).
Returns
-------
coord : an instance of this class
A new object with sky coordinates corresponding to the input ``xp``
and ``yp``.
See Also
--------
to_pixel : to do the inverse operation
astropy.wcs.utils.pixel_to_skycoord : the implementation of this method
"""
return pixel_to_skycoord(xp, yp, wcs=wcs, origin=origin, mode=mode, cls=cls)
def radial_velocity_correction(self, kind='barycentric', obstime=None,
location=None):
"""
Compute the correction required to convert a radial velocity at a given
time and place on the Earth's Surface to a barycentric or heliocentric
velocity.
Parameters
----------
kind : str
The kind of velocity correction. Must be 'barycentric' or
'heliocentric'.
obstime : `~astropy.time.Time` or None, optional
The time at which to compute the correction. If `None`, the
``obstime`` frame attribute on the `SkyCoord` will be used.
location : `~astropy.coordinates.EarthLocation` or None, optional
The observer location at which to compute the correction. If
`None`, the ``location`` frame attribute on the passed-in
``obstime`` will be used, and if that is None, the ``location``
frame attribute on the `SkyCoord` will be used.
Raises
------
ValueError
If either ``obstime`` or ``location`` are passed in (not ``None``)
when the frame attribute is already set on this `SkyCoord`.
TypeError
If ``obstime`` or ``location`` aren't provided, either as arguments
or as frame attributes.
Returns
-------
vcorr : `~astropy.units.Quantity` with velocity units
The correction with a positive sign. I.e., *add* this
to an observed radial velocity to get the barycentric (or
heliocentric) velocity. If m/s precision or better is needed,
see the notes below.
Notes
-----
The barycentric correction is calculated to higher precision than the
heliocentric correction and includes additional physics (e.g time dilation).
Use barycentric corrections if m/s precision is required.
The algorithm here is sufficient to perform corrections at the mm/s level, but
care is needed in application. Strictly speaking, the barycentric correction is
multiplicative and should be applied as::
sc = SkyCoord(1*u.deg, 2*u.deg)
vcorr = sc.rv_correction(kind='barycentric', obstime=t, location=loc)
rv = rv + vcorr + rv * vcorr / consts.c
If your target is nearby and/or has finite proper motion you may need to account
for terms arising from this. See Wright & Eastmann (2014) for details.
The default is for this method to use the builtin ephemeris for
computing the sun and earth location. Other ephemerides can be chosen
by setting the `~astropy.coordinates.solar_system_ephemeris` variable,
either directly or via ``with`` statement. For example, to use the JPL
ephemeris, do::
sc = SkyCoord(1*u.deg, 2*u.deg)
with coord.solar_system_ephemeris.set('jpl'):
rv += sc.rv_correction(obstime=t, location=loc)
"""
# has to be here to prevent circular imports
from .solar_system import get_body_barycentric_posvel, get_body_barycentric
# location validation
timeloc = getattr(obstime, 'location', None)
if location is None:
if self.location is not None:
location = self.location
if timeloc is not None:
raise ValueError('`location` cannot be in both the '
'passed-in `obstime` and this `SkyCoord` '
'because it is ambiguous which is meant '
'for the radial_velocity_correction.')
elif timeloc is not None:
location = timeloc
else:
raise TypeError('Must provide a `location` to '
'radial_velocity_correction, either as a '
'SkyCoord frame attribute, as an attribute on '
'the passed in `obstime`, or in the method '
'call.')
elif self.location is not None or timeloc is not None:
raise ValueError('Cannot compute radial velocity correction if '
'`location` argument is passed in and there is '
'also a `location` attribute on this SkyCoord or '
'the passed-in `obstime`.')
# obstime validation
if obstime is None:
obstime = self.obstime
if obstime is None:
raise TypeError('Must provide an `obstime` to '
'radial_velocity_correction, either as a '
'SkyCoord frame attribute or in the method '
'call.')
elif self.obstime is not None:
raise ValueError('Cannot compute radial velocity correction if '
'`obstime` argument is passed in and it is '
'inconsistent with the `obstime` frame '
'attribute on the SkyCoord')
pos_earth, v_earth = get_body_barycentric_posvel('earth', obstime)
if kind == 'barycentric':
v_origin_to_earth = v_earth
elif kind == 'heliocentric':
v_sun = get_body_barycentric_posvel('sun', obstime)[1]
v_origin_to_earth = v_earth - v_sun
else:
raise ValueError("`kind` argument to radial_velocity_correction must "
"be 'barycentric' or 'heliocentric', but got "
"'{}'".format(kind))
gcrs_p, gcrs_v = location.get_gcrs_posvel(obstime)
# transforming to GCRS is not the correct thing to do here, since we don't want to
# include aberration (or light deflection)? Instead, only apply parallax if necessary
if self.data.__class__ is UnitSphericalRepresentation:
targcart = self.icrs.cartesian
else:
# skycoord has distances so apply parallax
obs_icrs_cart = pos_earth + gcrs_p
icrs_cart = self.icrs.cartesian
targcart = icrs_cart - obs_icrs_cart
targcart /= targcart.norm()
if kind == 'barycentric':
beta_obs = (v_origin_to_earth + gcrs_v) / speed_of_light
gamma_obs = 1 / np.sqrt(1 - beta_obs.norm()**2)
gr = location.gravitational_redshift(obstime)
# barycentric redshift according to eq 28 in Wright & Eastmann (2014),
# neglecting Shapiro delay and effects of the star's own motion
zb = gamma_obs * (1 + targcart.dot(beta_obs)) / (1 + gr/speed_of_light) - 1
return zb * speed_of_light
else:
# do a simpler correction ignoring time dilation and gravitational redshift
# this is adequate since Heliocentric corrections shouldn't be used if
# cm/s precision is required.
return targcart.dot(v_origin_to_earth + gcrs_v)
# Table interactions
@classmethod
def guess_from_table(cls, table, **coord_kwargs):
r"""
A convenience method to create and return a new `SkyCoord` from the data
in an astropy Table.
This method matches table columns that start with the case-insensitive
names of the the components of the requested frames, if they are also
followed by a non-alphanumeric character. It will also match columns
that *end* with the component name if a non-alphanumeric character is
*before* it.
For example, the first rule means columns with names like
``'RA[J2000]'`` or ``'ra'`` will be interpreted as ``ra`` attributes for
`~astropy.coordinates.ICRS` frames, but ``'RAJ2000'`` or ``'radius'``
are *not*. Similarly, the second rule applied to the
`~astropy.coordinates.Galactic` frame means that a column named
``'gal_l'`` will be used as the the ``l`` component, but ``gall`` or
``'fill'`` will not.
The definition of alphanumeric here is based on Unicode's definition
of alphanumeric, except without ``_`` (which is normally considered
alphanumeric). So for ASCII, this means the non-alphanumeric characters
are ``<space>_!"#$%&'()*+,-./\:;<=>?@[]^`{|}~``).
Parameters
----------
table : astropy.Table
The table to load data from.
coord_kwargs
Any additional keyword arguments are passed directly to this class's
constructor.
Returns
-------
newsc : same as this class
The new `SkyCoord` (or subclass) object.
"""
inital_frame = coord_kwargs.get('frame')
frame = _get_frame([], coord_kwargs)
coord_kwargs['frame'] = inital_frame
comp_kwargs = {}
for comp_name in frame.representation_component_names:
# this matches things like 'ra[...]'' but *not* 'rad'.
# note that the "_" must be in there explicitly, because
# "alphanumeric" usually includes underscores.
starts_with_comp = comp_name + r'(\W|\b|_)'
# this part matches stuff like 'center_ra', but *not*
# 'aura'
ends_with_comp = r'.*(\W|\b|_)' + comp_name + r'\b'
# the final regex ORs together the two patterns
rex = re.compile('(' + starts_with_comp + ')|(' + ends_with_comp + ')',
re.IGNORECASE | re.UNICODE)
for col_name in table.colnames:
if rex.match(col_name):
if comp_name in comp_kwargs:
oldname = comp_kwargs[comp_name].name
msg = ('Found at least two matches for component "{0}"'
': "{1}" and "{2}". Cannot continue with this '
'ambiguity.')
raise ValueError(msg.format(comp_name, oldname, col_name))
comp_kwargs[comp_name] = table[col_name]
for k, v in comp_kwargs.items():
if k in coord_kwargs:
raise ValueError('Found column "{0}" in table, but it was '
'already provided as "{1}" keyword to '
'guess_from_table function.'.format(v.name, k))
else:
coord_kwargs[k] = v
return cls(**coord_kwargs)
# Name resolve
@classmethod
def from_name(cls, name, frame='icrs'):
"""
Given a name, query the CDS name resolver to attempt to retrieve
coordinate information for that object. The search database, sesame
url, and query timeout can be set through configuration items in
``astropy.coordinates.name_resolve`` -- see docstring for
`~astropy.coordinates.get_icrs_coordinates` for more
information.
Parameters
----------
name : str
The name of the object to get coordinates for, e.g. ``'M42'``.
frame : str or `BaseCoordinateFrame` class or instance
The frame to transform the object to.
Returns
-------
coord : SkyCoord
Instance of the SkyCoord class.
"""
from .name_resolve import get_icrs_coordinates
icrs_coord = get_icrs_coordinates(name)
icrs_sky_coord = cls(icrs_coord)
if frame in ('icrs', icrs_coord.__class__):
return icrs_sky_coord
else:
return icrs_sky_coord.transform_to(frame)
# <----------------Private utility functions below here------------------------->
def _get_frame_class(frame):
"""
Get a frame class from the input `frame`, which could be a frame name
string, or frame class.
"""
import inspect
if isinstance(frame, str):
frame_names = frame_transform_graph.get_names()
if frame not in frame_names:
raise ValueError('Coordinate frame {0} not in allowed values {1}'
.format(frame, sorted(frame_names)))
frame_cls = frame_transform_graph.lookup_name(frame)
elif inspect.isclass(frame) and issubclass(frame, BaseCoordinateFrame):
frame_cls = frame
else:
raise ValueError('Coordinate frame must be a frame name or frame class')
return frame_cls
def _get_frame(args, kwargs):
"""
Determine the coordinate frame from input SkyCoord args and kwargs. This
modifies args and/or kwargs in-place to remove the item that provided
`frame`. It also infers the frame if an input coordinate was provided and
checks for conflicts.
This allows for frame to be specified as a string like 'icrs' or a frame
class like ICRS, but not an instance ICRS() since the latter could have
non-default representation attributes which would require a three-way merge.
"""
frame = kwargs.pop('frame', None)
if frame is None and len(args) > 1:
# We do not allow frames to be passed as positional arguments if data
# is passed separately from frame.
for arg in args:
if isinstance(arg, (SkyCoord, BaseCoordinateFrame)):
raise ValueError("{0} instance cannot be passed as a positional "
"argument for the frame, pass it using the "
"frame= keyword instead.".format(arg.__class__.__name__))
# If the frame is an instance or SkyCoord, we split up the attributes and
# make it into a class.
if isinstance(frame, SkyCoord):
# Copy any extra attributes if they are not explicitly given.
for attr in frame._extra_frameattr_names:
kwargs.setdefault(attr, getattr(frame, attr))
frame = frame.frame
if isinstance(frame, BaseCoordinateFrame):
for attr in frame.get_frame_attr_names():
if attr in kwargs:
raise ValueError("cannot specify frame attribute '{0}' directly in SkyCoord since a frame instance was passed in".format(attr))
else:
kwargs[attr] = getattr(frame, attr)
frame = frame.__class__
if frame is not None:
# Frame was provided as kwarg so validate and coerce into corresponding frame.
frame_cls = _get_frame_class(frame)
frame_specified_explicitly = True
else:
# Look for the frame in args
for arg in args:
try:
frame_cls = _get_frame_class(arg)
frame_specified_explicitly = True
except ValueError:
pass
else:
args.remove(arg)
warnings.warn("Passing a frame as a positional argument is now "
"deprecated, use the frame= keyword argument "
"instead.", AstropyDeprecationWarning)
break
else:
# Not in args nor kwargs - default to icrs
frame_cls = ICRS
frame_specified_explicitly = False
# Check that the new frame doesn't conflict with existing coordinate frame
# if a coordinate is supplied in the args list. If the frame still had not
# been set by this point and a coordinate was supplied, then use that frame.
for arg in args:
# this catches the "single list passed in" case. For that case we want
# to allow the first argument to set the class. That's OK because
# _parse_coordinate_arg goes and checks that the frames match between
# the first and all the others
if (isinstance(arg, (collections.Sequence, np.ndarray)) and
len(args) == 1 and len(arg) > 0):
arg = arg[0]
coord_frame_obj = coord_frame_cls = None
if isinstance(arg, BaseCoordinateFrame):
coord_frame_obj = arg
elif isinstance(arg, SkyCoord):
coord_frame_obj = arg.frame
if coord_frame_obj is not None:
coord_frame_cls = coord_frame_obj.__class__
frame_diff = coord_frame_obj.get_representation_cls('s')
if frame_diff is not None:
# we do this check because otherwise if there's no default
# differential (i.e. it is None), the code below chokes. but
# None still gets through if the user *requests* it
kwargs.setdefault('differential_type', frame_diff)
if coord_frame_cls is not None:
if not frame_specified_explicitly:
frame_cls = coord_frame_cls
elif frame_cls is not coord_frame_cls:
raise ValueError("Cannot override frame='{0}' of input coordinate with "
"new frame='{1}'. Instead transform the coordinate."
.format(coord_frame_cls.__name__, frame_cls.__name__))
frame_cls_kwargs = {}
# TODO: deprecate representation, remove this in future
_normalize_representation_type(kwargs)
if 'representation_type' in kwargs:
frame_cls_kwargs['representation_type'] = _get_repr_cls(
kwargs['representation_type'])
if 'differential_type' in kwargs:
frame_cls_kwargs['differential_type'] = _get_diff_cls(
kwargs['differential_type'])
return frame_cls(**frame_cls_kwargs)
def _get_representation_component_units(args, kwargs):
"""
Get the unit from kwargs for the *representation* components (not the
differentials).
"""
if 'unit' not in kwargs:
units = [None, None, None]
else:
units = kwargs.pop('unit')
if isinstance(units, str):
units = [x.strip() for x in units.split(',')]
# Allow for input like unit='deg' or unit='m'
if len(units) == 1:
units = [units[0], units[0], units[0]]
elif isinstance(units, (Unit, IrreducibleUnit)):
units = [units, units, units]
try:
units = [(Unit(x) if x else None) for x in units]
units.extend(None for x in range(3 - len(units)))
if len(units) > 3:
raise ValueError()
except Exception:
raise ValueError('Unit keyword must have one to three unit values as '
'tuple or comma-separated string')
return units
def _parse_coordinate_arg(coords, frame, units, init_kwargs):
"""
Single unnamed arg supplied. This must be:
- Coordinate frame with data
- Representation
- SkyCoord
- List or tuple of:
- String which splits into two values
- Iterable with two values
- SkyCoord, frame, or representation objects.
Returns a dict mapping coordinate attribute names to values (or lists of
values)
"""
is_scalar = False # Differentiate between scalar and list input
valid_kwargs = {} # Returned dict of lon, lat, and distance (optional)
frame_attr_names = list(frame.representation_component_names.keys())
repr_attr_names = list(frame.representation_component_names.values())
repr_attr_classes = list(frame.representation.attr_classes.values())
n_attr_names = len(repr_attr_names)
# Turn a single string into a list of strings for convenience
if isinstance(coords, str):
is_scalar = True
coords = [coords]
if isinstance(coords, (SkyCoord, BaseCoordinateFrame)):
# Note that during parsing of `frame` it is checked that any coordinate
# args have the same frame as explicitly supplied, so don't worry here.
if not coords.has_data:
raise ValueError('Cannot initialize from a frame without coordinate data')
data = coords.data.represent_as(frame.representation_type)
values = [] # List of values corresponding to representation attrs
repr_attr_name_to_drop = []
for repr_attr_name in repr_attr_names:
# If coords did not have an explicit distance then don't include in initializers.
if (isinstance(coords.data, UnitSphericalRepresentation) and
repr_attr_name == 'distance'):
repr_attr_name_to_drop.append(repr_attr_name)
continue
# Get the value from `data` in the eventual representation
values.append(getattr(data, repr_attr_name))
# drop the ones that were skipped because they were distances
for nametodrop in repr_attr_name_to_drop:
nameidx = repr_attr_names.index(nametodrop)
del repr_attr_names[nameidx]
del units[nameidx]
del frame_attr_names[nameidx]
del repr_attr_classes[nameidx]
if coords.data.differentials and 's' in coords.data.differentials:
orig_vel = coords.data.differentials['s']
vel = coords.data.represent_as(frame.representation, frame.get_representation_cls('s')).differentials['s']
for frname, reprname in frame.get_representation_component_names('s').items():
if (reprname == 'd_distance' and not hasattr(orig_vel, reprname) and
'unit' in orig_vel.get_name()):
continue
values.append(getattr(vel, reprname))
units.append(None)
frame_attr_names.append(frname)
repr_attr_names.append(reprname)
repr_attr_classes.append(vel.attr_classes[reprname])
for attr in frame_transform_graph.frame_attributes:
value = getattr(coords, attr, None)
use_value = (isinstance(coords, SkyCoord)
or attr not in coords._attr_names_with_defaults)
if use_value and value is not None:
valid_kwargs[attr] = value
elif isinstance(coords, BaseRepresentation):
if coords.differentials and 's' in coords.differentials:
diffs = frame.get_representation_cls('s')
data = coords.represent_as(frame.representation_type, diffs)
values = [getattr(data, repr_attr_name) for repr_attr_name in repr_attr_names]
for frname, reprname in frame.get_representation_component_names('s').items():
values.append(getattr(data.differentials['s'], reprname))
units.append(None)
frame_attr_names.append(frname)
repr_attr_names.append(reprname)
repr_attr_classes.append(data.differentials['s'].attr_classes[reprname])
else:
data = coords.represent_as(frame.representation)
values = [getattr(data, repr_attr_name) for repr_attr_name in repr_attr_names]
elif (isinstance(coords, np.ndarray) and coords.dtype.kind in 'if'
and coords.ndim == 2 and coords.shape[1] <= 3):
# 2-d array of coordinate values. Handle specially for efficiency.
values = coords.transpose() # Iterates over repr attrs
elif isinstance(coords, (collections.Sequence, np.ndarray)):
# Handles list-like input.
vals = []
is_ra_dec_representation = ('ra' in frame.representation_component_names and
'dec' in frame.representation_component_names)
coord_types = (SkyCoord, BaseCoordinateFrame, BaseRepresentation)
if any(isinstance(coord, coord_types) for coord in coords):
# this parsing path is used when there are coordinate-like objects
# in the list - instead of creating lists of values, we create
# SkyCoords from the list elements and then combine them.
scs = [SkyCoord(coord, **init_kwargs) for coord in coords]
# Check that all frames are equivalent
for sc in scs[1:]:
if not sc.is_equivalent_frame(scs[0]):
raise ValueError("List of inputs don't have equivalent "
"frames: {0} != {1}".format(sc, scs[0]))
# Now use the first to determine if they are all UnitSpherical
allunitsphrepr = isinstance(scs[0].data, UnitSphericalRepresentation)
# get the frame attributes from the first coord in the list, because
# from the above we know it matches all the others. First copy over
# the attributes that are in the frame itself, then copy over any
# extras in the SkyCoord
for fattrnm in scs[0].frame.frame_attributes:
valid_kwargs[fattrnm] = getattr(scs[0].frame, fattrnm)
for fattrnm in scs[0]._extra_frameattr_names:
valid_kwargs[fattrnm] = getattr(scs[0], fattrnm)
# Now combine the values, to be used below
values = []
for data_attr_name, repr_attr_name in zip(frame_attr_names, repr_attr_names):
if allunitsphrepr and repr_attr_name == 'distance':
# if they are *all* UnitSpherical, don't give a distance
continue
data_vals = []
for sc in scs:
data_val = getattr(sc, data_attr_name)
data_vals.append(data_val.reshape(1,) if sc.isscalar else data_val)
concat_vals = np.concatenate(data_vals)
# Hack because np.concatenate doesn't fully work with Quantity
if isinstance(concat_vals, u.Quantity):
concat_vals._unit = data_val.unit
values.append(concat_vals)
else:
# none of the elements are "frame-like"
# turn into a list of lists like [[v1_0, v2_0, v3_0], ... [v1_N, v2_N, v3_N]]
for coord in coords:
if isinstance(coord, str):
coord1 = coord.split()
if len(coord1) == 6:
coord = (' '.join(coord1[:3]), ' '.join(coord1[3:]))
elif is_ra_dec_representation:
coord = _parse_ra_dec(coord)
else:
coord = coord1
vals.append(coord) # Assumes coord is a sequence at this point
# Do some basic validation of the list elements: all have a length and all
# lengths the same
try:
n_coords = sorted(set(len(x) for x in vals))
except Exception:
raise ValueError('One or more elements of input sequence does not have a length')
if len(n_coords) > 1:
raise ValueError('Input coordinate values must have same number of elements, found {0}'
.format(n_coords))
n_coords = n_coords[0]
# Must have no more coord inputs than representation attributes
if n_coords > n_attr_names:
raise ValueError('Input coordinates have {0} values but '
'representation {1} only accepts {2}'
.format(n_coords,
frame.representation_type.get_name(),
n_attr_names))
# Now transpose vals to get [(v1_0 .. v1_N), (v2_0 .. v2_N), (v3_0 .. v3_N)]
# (ok since we know it is exactly rectangular). (Note: can't just use zip(*values)
# because Longitude et al distinguishes list from tuple so [a1, a2, ..] is needed
# while (a1, a2, ..) doesn't work.
values = [list(x) for x in zip(*vals)]
if is_scalar:
values = [x[0] for x in values]
else:
raise ValueError('Cannot parse coordinates from first argument')
# Finally we have a list of values from which to create the keyword args
# for the frame initialization. Validate by running through the appropriate
# class initializer and supply units (which might be None).
try:
for frame_attr_name, repr_attr_class, value, unit in zip(
frame_attr_names, repr_attr_classes, values, units):
valid_kwargs[frame_attr_name] = repr_attr_class(value, unit=unit,
copy=False)
except Exception as err:
raise ValueError('Cannot parse first argument data "{0}" for attribute '
'{1}'.format(value, frame_attr_name), err)
return valid_kwargs
def _get_representation_attrs(frame, units, kwargs):
"""
Find instances of the "representation attributes" for specifying data
for this frame. Pop them off of kwargs, run through the appropriate class
constructor (to validate and apply unit), and put into the output
valid_kwargs. "Representation attributes" are the frame-specific aliases
for the underlying data values in the representation, e.g. "ra" for "lon"
for many equatorial spherical representations, or "w" for "x" in the
cartesian representation of Galactic.
This also gets any *differential* kwargs, because they go into the same
frame initializer later on.
"""
frame_attr_names = frame.representation_component_names.keys()
repr_attr_classes = frame.representation_type.attr_classes.values()
valid_kwargs = {}
for frame_attr_name, repr_attr_class, unit in zip(frame_attr_names, repr_attr_classes, units):
value = kwargs.pop(frame_attr_name, None)
if value is not None:
valid_kwargs[frame_attr_name] = repr_attr_class(value, unit=unit)
# also check the differentials. They aren't included in the units keyword,
# so we only look for the names.
differential_type = frame.differential_type
if differential_type is not None:
for frame_name, repr_name in frame.get_representation_component_names('s').items():
diff_attr_class = differential_type.attr_classes[repr_name]
value = kwargs.pop(frame_name, None)
if value is not None:
valid_kwargs[frame_name] = diff_attr_class(value)
return valid_kwargs
def _parse_ra_dec(coord_str):
"""
Parse RA and Dec values from a coordinate string. Currently the
following formats are supported:
* space separated 6-value format
* space separated <6-value format, this requires a plus or minus sign
separation between RA and Dec
* sign separated format
* JHHMMSS.ss+DDMMSS.ss format, with up to two optional decimal digits
* JDDDMMSS.ss+DDMMSS.ss format, with up to two optional decimal digits
Parameters
----------
coord_str : str
Coordinate string to parse.
Returns
-------
coord : str or list of str
Parsed coordinate values.
"""
if isinstance(coord_str, str):
coord1 = coord_str.split()
else:
# This exception should never be raised from SkyCoord
raise TypeError('coord_str must be a single str')
if len(coord1) == 6:
coord = (' '.join(coord1[:3]), ' '.join(coord1[3:]))
elif len(coord1) > 2:
coord = PLUS_MINUS_RE.split(coord_str)
coord = (coord[0], ' '.join(coord[1:]))
elif len(coord1) == 1:
match_j = J_PREFIXED_RA_DEC_RE.match(coord_str)
if match_j:
coord = match_j.groups()
if len(coord[0].split('.')[0]) == 7:
coord = ('{0} {1} {2}'.
format(coord[0][0:3], coord[0][3:5], coord[0][5:]),
'{0} {1} {2}'.
format(coord[1][0:3], coord[1][3:5], coord[1][5:]))
else:
coord = ('{0} {1} {2}'.
format(coord[0][0:2], coord[0][2:4], coord[0][4:]),
'{0} {1} {2}'.
format(coord[1][0:3], coord[1][3:5], coord[1][5:]))
else:
coord = PLUS_MINUS_RE.split(coord_str)
coord = (coord[0], ' '.join(coord[1:]))
else:
coord = coord1
return coord
|
3d57bd82039526075c5eadcc77189cb2da0f1f123527ecd81ac945b636f65877 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
_tabversion = '3.8'
_lextokens = set(('UINT', 'SIMPLE_UNIT', 'DEGREE', 'MINUTE', 'HOUR', 'COLON', 'UFLOAT', 'SIGN', 'SECOND'))
_lexreflags = 0
_lexliterals = ''
_lexstateinfo = {'INITIAL': 'inclusive'}
_lexstatere = {'INITIAL': [('(?P<t_UFLOAT>((\\d+\\.\\d*)|(\\.\\d+))([eE][+-−]?\\d+)?)|(?P<t_UINT>\\d+)|(?P<t_SIGN>[+−-])|(?P<t_SIMPLE_UNIT>(?:karcsec)|(?:uarcsec)|(?:Earcmin)|(?:Zdeg)|(?:crad)|(?:cycle)|(?:hectoradian)|(?:Yarcmin)|(?:kiloarcsecond)|(?:zeptoarcminute)|(?:adeg)|(?:darcmin)|(?:ddeg)|(?:exaradian)|(?:parcsec)|(?:yoctoradian)|(?:arcsecond)|(?:petadegree)|(?:petaarcminute)|(?:microarcsecond)|(?:mas)|(?:parcmin)|(?:hdeg)|(?:narcmin)|(?:attodegree)|(?:kilodegree)|(?:zettaradian)|(?:fdeg)|(?:zeptoradian)|(?:microradian)|(?:Gdeg)|(?:hectodegree)|(?:attoarcsecond)|(?:Marcmin)|(?:exadegree)|(?:femtodegree)|(?:yottaradian)|(?:pdeg)|(?:zarcmin)|(?:kiloarcminute)|(?:urad)|(?:teraarcsecond)|(?:nrad)|(?:carcsec)|(?:Pdeg)|(?:Yrad)|(?:yrad)|(?:picoarcsecond)|(?:aarcsec)|(?:dekaradian)|(?:Zrad)|(?:femtoradian)|(?:yarcsec)|(?:arcmin)|(?:arcsec)|(?:yottadegree)|(?:drad)|(?:dekadegree)|(?:zdeg)|(?:zeptoarcsecond)|(?:farcmin)|(?:Parcmin)|(?:decaarcminute)|(?:nanoarcminute)|(?:nanoarcsecond)|(?:Tdeg)|(?:decaarcsecond)|(?:nanodegree)|(?:farcsec)|(?:femtoarcminute)|(?:microdegree)|(?:deciarcsecond)|(?:deciarcminute)|(?:attoradian)|(?:dadeg)|(?:decidegree)|(?:hectoarcminute)|(?:milliarcsecond)|(?:femtoarcsecond)|(?:megaarcminute)|(?:yoctoarcminute)|(?:zrad)|(?:hectoarcsecond)|(?:frad)|(?:centiarcsecond)|(?:carcmin)|(?:Garcmin)|(?:decadegree)|(?:Grad)|(?:petaarcsecond)|(?:gigaarcsecond)|(?:megaradian)|(?:Tarcsec)|(?:Prad)|(?:zettadegree)|(?:yottaarcminute)|(?:mrad)|(?:yottaarcsecond)|(?:exaarcminute)|(?:harcmin)|(?:dekaarcsecond)|(?:cy)|(?:ndeg)|(?:teraradian)|(?:teradegree)|(?:Zarcsec)|(?:gigadegree)|(?:Mdeg)|(?:Mrad)|(?:centiarcminute)|(?:uarcmin)|(?:picoradian)|(?:radian)|(?:ydeg)|(?:milliarcminute)|(?:deciradian)|(?:narcsec)|(?:Trad)|(?:picodegree)|(?:yoctodegree)|(?:zettaarcminute)|(?:daarcmin)|(?:arcminute)|(?:yarcmin)|(?:kdeg)|(?:Earcsec)|(?:Edeg)|(?:harcsec)|(?:rad)|(?:centidegree)|(?:Garcsec)|(?:marcsec)|(?:megaarcsecond)|(?:attoarcminute)|(?:cdeg)|(?:Erad)|(?:kiloradian)|(?:daarcsec)|(?:Parcsec)|(?:megadegree)|(?:millidegree)|(?:centiradian)|(?:uas)|(?:teraarcminute)|(?:prad)|(?:yoctoarcsecond)|(?:hrad)|(?:picoarcminute)|(?:petaradian)|(?:Marcsec)|(?:marcmin)|(?:Tarcmin)|(?:zeptodegree)|(?:Yarcsec)|(?:gigaarcminute)|(?:Zarcmin)|(?:arad)|(?:karcmin)|(?:darcsec)|(?:exaarcsecond)|(?:nanoradian)|(?:udeg)|(?:zarcsec)|(?:Ydeg)|(?:decaradian)|(?:milliradian)|(?:aarcmin)|(?:zettaarcsecond)|(?:darad)|(?:microarcminute)|(?:mdeg)|(?:dekaarcminute)|(?:krad)|(?:gigaradian))|(?P<t_MINUTE>m(in(ute(s)?)?)?|′|\\\'|ᵐ)|(?P<t_SECOND>s(ec(ond(s)?)?)?|″|\\"|ˢ)|(?P<t_DEGREE>d(eg(ree(s)?)?)?|°)|(?P<t_HOUR>hour(s)?|h(r)?|ʰ)|(?P<t_COLON>:)', [None, ('t_UFLOAT', 'UFLOAT'), None, None, None, None, ('t_UINT', 'UINT'), ('t_SIGN', 'SIGN'), ('t_SIMPLE_UNIT', 'SIMPLE_UNIT'), (None, 'MINUTE'), None, None, None, (None, 'SECOND'), None, None, None, (None, 'DEGREE'), None, None, None, (None, 'HOUR'), None, None, (None, 'COLON')])]}
_lexstateignore = {'INITIAL': ' '}
_lexstateerrorf = {'INITIAL': 't_error'}
_lexstateeoff = {}
|
f13b284e1b4af4b5f637e038a57a4161a37c203f8fa67fd8b725c21bc19d50d3 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Currently the only site accessible without internet access is the Royal
Greenwich Observatory, as an example (and for testing purposes). In future
releases, a canonical set of sites may be bundled into astropy for when the
online registry is unavailable.
Additions or corrections to the observatory list can be submitted via Pull
Request to the [astropy-data GitHub repository](https://github.com/astropy/astropy-data),
updating the ``location.json`` file.
"""
import json
from difflib import get_close_matches
from collections import Mapping
from ..utils.data import get_pkg_data_contents, get_file_contents
from .earth import EarthLocation
from .errors import UnknownSiteException
from .. import units as u
class SiteRegistry(Mapping):
"""
A bare-bones registry of EarthLocation objects.
This acts as a mapping (dict-like object) but with the important caveat that
it's always transforms its inputs to lower-case. So keys are always all
lower-case, and even if you ask for something that's got mixed case, it will
be interpreted as the all lower-case version.
"""
def __init__(self):
# the keys to this are always lower-case
self._lowercase_names_to_locations = {}
# these can be whatever case is appropriate
self._names = []
def __getitem__(self, site_name):
"""
Returns an EarthLocation for a known site in this registry.
Parameters
----------
site_name : str
Name of the observatory (case-insensitive).
Returns
-------
site : `~astropy.coordinates.EarthLocation`
The location of the observatory.
"""
if site_name.lower() not in self._lowercase_names_to_locations:
# If site name not found, find close matches and suggest them in error
close_names = get_close_matches(site_name, self._lowercase_names_to_locations)
close_names = sorted(close_names, key=len)
raise UnknownSiteException(site_name, "the 'names' attribute", close_names=close_names)
return self._lowercase_names_to_locations[site_name.lower()]
def __len__(self):
return len(self._lowercase_names_to_locations)
def __iter__(self):
return iter(self._lowercase_names_to_locations)
def __contains__(self, site_name):
return site_name.lower() in self._lowercase_names_to_locations
@property
def names(self):
"""
The names in this registry. Note that these are *not* exactly the same
as the keys: keys are always lower-case, while `names` is what you
should use for the actual readable names (which may be case-sensitive)
Returns
-------
site : list of str
The names of the sites in this registry
"""
return sorted(self._names)
def add_site(self, names, locationobj):
"""
Adds a location to the registry.
Parameters
----------
names : list of str
All the names this site should go under
locationobj : `~astropy.coordinates.EarthLocation`
The actual site object
"""
for name in names:
self._lowercase_names_to_locations[name.lower()] = locationobj
self._names.append(name)
@classmethod
def from_json(cls, jsondb):
reg = cls()
for site in jsondb:
site_info = jsondb[site]
location = EarthLocation.from_geodetic(site_info['longitude'] * u.Unit(site_info['longitude_unit']),
site_info['latitude'] * u.Unit(site_info['latitude_unit']),
site_info['elevation'] * u.Unit(site_info['elevation_unit']))
location.info.name = site_info['name']
reg.add_site([site] + site_info['aliases'], location)
reg._loaded_jsondb = jsondb
return reg
def get_builtin_sites():
"""
Load observatory database from data/observatories.json and parse them into
a SiteRegistry.
"""
jsondb = json.loads(get_pkg_data_contents('data/sites.json'))
return SiteRegistry.from_json(jsondb)
def get_downloaded_sites(jsonurl=None):
"""
Load observatory database from data.astropy.org and parse into a SiteRegistry
"""
# we explicitly set the encoding because the default is to leave it set by
# the users' locale, which may fail if it's not matched to the sites.json
if jsonurl is None:
content = get_pkg_data_contents('coordinates/sites.json', encoding='UTF-8')
else:
content = get_file_contents(jsonurl, encoding='UTF-8')
jsondb = json.loads(content)
return SiteRegistry.from_json(jsondb)
|
fcac04cd6c40af0e586bd6d5d8f1e744ac0f97d33b04512caefa95058b693acd | """
In this module, we define the coordinate representation classes, which are
used to represent low-level cartesian, spherical, cylindrical, and other
coordinates.
"""
import abc
import functools
import operator
from collections import OrderedDict
import inspect
import warnings
import numpy as np
import astropy.units as u
from .angles import Angle, Longitude, Latitude
from .distances import Distance
from ..utils import ShapedLikeNDArray, classproperty
from ..utils import deprecated_attribute
from ..utils.exceptions import AstropyDeprecationWarning
from ..utils.misc import InheritDocstrings
from ..utils.compat import NUMPY_LT_1_12, NUMPY_LT_1_14
__all__ = ["BaseRepresentationOrDifferential", "BaseRepresentation",
"CartesianRepresentation", "SphericalRepresentation",
"UnitSphericalRepresentation", "RadialRepresentation",
"PhysicsSphericalRepresentation", "CylindricalRepresentation",
"BaseDifferential", "CartesianDifferential",
"BaseSphericalDifferential", "BaseSphericalCosLatDifferential",
"SphericalDifferential", "SphericalCosLatDifferential",
"UnitSphericalDifferential", "UnitSphericalCosLatDifferential",
"RadialDifferential", "CylindricalDifferential",
"PhysicsSphericalDifferential"]
# Module-level dict mapping representation string alias names to classes.
# This is populated by the metaclass init so all representation and differential
# classes get registered automatically.
REPRESENTATION_CLASSES = {}
DIFFERENTIAL_CLASSES = {}
# recommended_units deprecation message; if the attribute is removed later,
# also remove its use in BaseFrame._get_representation_info.
_recommended_units_deprecation = """
The 'recommended_units' attribute is deprecated since 3.0 and may be removed
in a future version. Its main use, of representing angles in degrees in frames,
is now done automatically in frames. Further overrides are discouraged but can
be done using a frame's ``frame_specific_representation_info``.
"""
def _array2string(values, prefix=''):
# Mimic numpy >=1.12 array2string, in which structured arrays are
# typeset taking into account all printoptions.
kwargs = {'separator': ', ', 'prefix': prefix}
if NUMPY_LT_1_12: # pragma: no cover
# Mimic StructureFormat from numpy >=1.12 assuming float-only data.
from numpy.core.arrayprint import FloatFormat
opts = np.get_printoptions()
format_functions = [FloatFormat(np.atleast_1d(values[component]).ravel(),
precision=opts['precision'],
suppress_small=opts['suppress'])
for component in values.dtype.names]
def fmt(x):
return '({})'.format(', '.join(format_function(field)
for field, format_function in
zip(x, format_functions)))
# Before 1.12, structures arrays were set as "numpystr",
# so that is the formmater we need to replace.
kwargs['formatter'] = {'numpystr': fmt}
kwargs['style'] = fmt
else:
kwargs['formatter'] = {}
if NUMPY_LT_1_14: # in 1.14, style is no longer used (and deprecated)
kwargs['style'] = repr
return np.array2string(values, **kwargs)
def _combine_xyz(x, y, z, xyz_axis=0):
"""
Combine components ``x``, ``y``, ``z`` into a single Quantity array.
Parameters
----------
x, y, z : `~astropy.units.Quantity`
The individual x, y, and z components.
xyz_axis : int, optional
The axis in the final array along which the x, y, z components
should be stored (default: 0).
Returns
-------
xyz : `~astropy.units.Quantity`
With dimension 3 along ``xyz_axis``, i.e., using the default of ``0``,
the shape will be ``(3,) + x.shape``.
"""
# Add new axis in x, y, z so one can concatenate them around it.
# NOTE: just use np.stack once our minimum numpy version is 1.10.
result_ndim = x.ndim + 1
if not -result_ndim <= xyz_axis < result_ndim:
raise IndexError('xyz_axis {0} out of bounds [-{1}, {1})'
.format(xyz_axis, result_ndim))
if xyz_axis < 0:
xyz_axis += result_ndim
# Get x, y, z to the same units (this is very fast for identical units)
# since np.concatenate cannot deal with quantity.
cls = x.__class__
y = cls(y, x.unit, copy=False)
z = cls(z, x.unit, copy=False)
sh = x.shape
sh = sh[:xyz_axis] + (1,) + sh[xyz_axis:]
xyz_value = np.concatenate([c.reshape(sh).value for c in (x, y, z)],
axis=xyz_axis)
return cls(xyz_value, unit=x.unit, copy=False)
class BaseRepresentationOrDifferential(ShapedLikeNDArray):
"""3D coordinate representations and differentials.
Parameters
----------
comp1, comp2, comp3 : `~astropy.units.Quantity` or subclass
The components of the 3D point or differential. The names are the
keys and the subclasses the values of the ``attr_classes`` attribute.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
# Ensure multiplication/division with ndarray or Quantity doesn't lead to
# object arrays.
__array_priority__ = 50000
def __init__(self, *args, **kwargs):
# make argument a list, so we can pop them off.
args = list(args)
components = self.components
attrs = []
for component in components:
try:
attrs.append(args.pop(0) if args else kwargs.pop(component))
except KeyError:
raise TypeError('__init__() missing 1 required positional '
'argument: {0!r}'.format(component))
copy = args.pop(0) if args else kwargs.pop('copy', True)
if args:
raise TypeError('unexpected arguments: {0}'.format(args))
if kwargs:
for component in components:
if component in kwargs:
raise TypeError("__init__() got multiple values for "
"argument {0!r}".format(component))
raise TypeError('unexpected keyword arguments: {0}'.format(kwargs))
# Pass attributes through the required initializing classes.
attrs = [self.attr_classes[component](attr, copy=copy)
for component, attr in zip(components, attrs)]
try:
attrs = np.broadcast_arrays(*attrs, subok=True)
except ValueError:
if len(components) <= 2:
c_str = ' and '.join(components)
else:
c_str = ', '.join(components[:2]) + ', and ' + components[2]
raise ValueError("Input parameters {0} cannot be broadcast"
.format(c_str))
# Set private attributes for the attributes. (If not defined explicitly
# on the class, the metaclass will define properties to access these.)
for component, attr in zip(components, attrs):
setattr(self, '_' + component, attr)
@classmethod
def get_name(cls):
"""Name of the representation or differential.
In lower case, with any trailing 'representation' or 'differential'
removed. (E.g., 'spherical' for
`~astropy.coordinates.SphericalRepresentation` or
`~astropy.coordinates.SphericalDifferential`.)
"""
name = cls.__name__.lower()
if name.endswith('representation'):
name = name[:-14]
elif name.endswith('differential'):
name = name[:-12]
return name
# The two methods that any subclass has to define.
@classmethod
@abc.abstractmethod
def from_cartesian(cls, other):
"""Create a representation of this class from a supplied Cartesian one.
Parameters
----------
other : `CartesianRepresentation`
The representation to turn into this class
Returns
-------
representation : object of this class
A new representation of this class's type.
"""
# Note: the above docstring gets overridden for differentials.
raise NotImplementedError()
@abc.abstractmethod
def to_cartesian(self):
"""Convert the representation to its Cartesian form.
Note that any differentials get dropped.
Returns
-------
cartrepr : `CartesianRepresentation`
The representation in Cartesian form.
"""
# Note: the above docstring gets overridden for differentials.
raise NotImplementedError()
@property
def components(self):
"""A tuple with the in-order names of the coordinate components."""
return tuple(self.attr_classes)
def _apply(self, method, *args, **kwargs):
"""Create a new representation or differential with ``method`` applied
to the component data.
In typical usage, the method is any of the shape-changing methods for
`~numpy.ndarray` (``reshape``, ``swapaxes``, etc.), as well as those
picking particular elements (``__getitem__``, ``take``, etc.), which
are all defined in `~astropy.utils.misc.ShapedLikeNDArray`. It will be
applied to the underlying arrays (e.g., ``x``, ``y``, and ``z`` for
`~astropy.coordinates.CartesianRepresentation`), with the results used
to create a new instance.
Internally, it is also used to apply functions to the components
(in particular, `~numpy.broadcast_to`).
Parameters
----------
method : str or callable
If str, it is the name of a method that is applied to the internal
``components``. If callable, the function is applied.
args : tuple
Any positional arguments for ``method``.
kwargs : dict
Any keyword arguments for ``method``.
"""
if callable(method):
apply_method = lambda array: method(array, *args, **kwargs)
else:
apply_method = operator.methodcaller(method, *args, **kwargs)
new = super().__new__(self.__class__)
for component in self.components:
setattr(new, '_' + component,
apply_method(getattr(self, component)))
return new
@property
def shape(self):
"""The shape of the instance and underlying arrays.
Like `~numpy.ndarray.shape`, can be set to a new shape by assigning a
tuple. Note that if different instances share some but not all
underlying data, setting the shape of one instance can make the other
instance unusable. Hence, it is strongly recommended to get new,
reshaped instances with the ``reshape`` method.
Raises
------
AttributeError
If the shape of any of the components cannot be changed without the
arrays being copied. For these cases, use the ``reshape`` method
(which copies any arrays that cannot be reshaped in-place).
"""
return getattr(self, self.components[0]).shape
@shape.setter
def shape(self, shape):
# We keep track of arrays that were already reshaped since we may have
# to return those to their original shape if a later shape-setting
# fails. (This can happen since coordinates are broadcast together.)
reshaped = []
oldshape = self.shape
for component in self.components:
val = getattr(self, component)
if val.size > 1:
try:
val.shape = shape
except AttributeError:
for val2 in reshaped:
val2.shape = oldshape
raise
else:
reshaped.append(val)
# Required to support multiplication and division, and defined by the base
# representation and differential classes.
@abc.abstractmethod
def _scale_operation(self, op, *args):
raise NotImplementedError()
def __mul__(self, other):
return self._scale_operation(operator.mul, other)
def __rmul__(self, other):
return self.__mul__(other)
def __truediv__(self, other):
return self._scale_operation(operator.truediv, other)
def __div__(self, other): # pragma: py2
return self._scale_operation(operator.truediv, other)
def __neg__(self):
return self._scale_operation(operator.neg)
# Follow numpy convention and make an independent copy.
def __pos__(self):
return self.copy()
# Required to support addition and subtraction, and defined by the base
# representation and differential classes.
@abc.abstractmethod
def _combine_operation(self, op, other, reverse=False):
raise NotImplementedError()
def __add__(self, other):
return self._combine_operation(operator.add, other)
def __radd__(self, other):
return self._combine_operation(operator.add, other, reverse=True)
def __sub__(self, other):
return self._combine_operation(operator.sub, other)
def __rsub__(self, other):
return self._combine_operation(operator.sub, other, reverse=True)
# The following are used for repr and str
@property
def _values(self):
"""Turn the coordinates into a record array with the coordinate values.
The record array fields will have the component names.
"""
coo_items = [(c, getattr(self, c)) for c in self.components]
result = np.empty(self.shape, [(c, coo.dtype) for c, coo in coo_items])
for c, coo in coo_items:
result[c] = coo.value
return result
@property
def _units(self):
"""Return a dictionary with the units of the coordinate components."""
return dict([(component, getattr(self, component).unit)
for component in self.components])
@property
def _unitstr(self):
units_set = set(self._units.values())
if len(units_set) == 1:
unitstr = units_set.pop().to_string()
else:
unitstr = '({0})'.format(
', '.join([self._units[component].to_string()
for component in self.components]))
return unitstr
def __str__(self):
return '{0} {1:s}'.format(_array2string(self._values), self._unitstr)
def __repr__(self):
prefixstr = ' '
arrstr = _array2string(self._values, prefix=prefixstr)
diffstr = ''
if getattr(self, 'differentials', None):
diffstr = '\n (has differentials w.r.t.: {0})'.format(
', '.join([repr(key) for key in self.differentials.keys()]))
unitstr = ('in ' + self._unitstr) if self._unitstr else '[dimensionless]'
return '<{0} ({1}) {2:s}\n{3}{4}{5}>'.format(
self.__class__.__name__, ', '.join(self.components),
unitstr, prefixstr, arrstr, diffstr)
def _make_getter(component):
"""Make an attribute getter for use in a property.
Parameters
----------
component : str
The name of the component that should be accessed. This assumes the
actual value is stored in an attribute of that name prefixed by '_'.
"""
# This has to be done in a function to ensure the reference to component
# is not lost/redirected.
component = '_' + component
def get_component(self):
return getattr(self, component)
return get_component
# Need to also subclass ABCMeta rather than type, so that this meta class can
# be combined with a ShapedLikeNDArray subclass (which is an ABC). Without it:
# "TypeError: metaclass conflict: the metaclass of a derived class must be a
# (non-strict) subclass of the metaclasses of all its bases"
class MetaBaseRepresentation(InheritDocstrings, abc.ABCMeta):
def __init__(cls, name, bases, dct):
super().__init__(name, bases, dct)
# Register representation name (except for BaseRepresentation)
if cls.__name__ == 'BaseRepresentation':
return
if 'attr_classes' not in dct:
raise NotImplementedError('Representations must have an '
'"attr_classes" class attribute.')
if 'recommended_units' in dct:
warnings.warn(_recommended_units_deprecation,
AstropyDeprecationWarning)
# Ensure we don't override the property that warns about the
# deprecation, but that the value remains the same.
dct.setdefault('_recommended_units', dct.pop('recommended_units'))
repr_name = cls.get_name()
if repr_name in REPRESENTATION_CLASSES:
raise ValueError("Representation class {0} already defined"
.format(repr_name))
REPRESENTATION_CLASSES[repr_name] = cls
# define getters for any component that does not yet have one.
for component in cls.attr_classes:
if not hasattr(cls, component):
setattr(cls, component,
property(_make_getter(component),
doc=("The '{0}' component of the points(s)."
.format(component))))
class BaseRepresentation(BaseRepresentationOrDifferential,
metaclass=MetaBaseRepresentation):
"""Base for representing a point in a 3D coordinate system.
Parameters
----------
comp1, comp2, comp3 : `~astropy.units.Quantity` or subclass
The components of the 3D points. The names are the keys and the
subclasses the values of the ``attr_classes`` attribute.
differentials : dict, `BaseDifferential`, optional
Any differential classes that should be associated with this
representation. The input must either be a single `BaseDifferential`
subclass instance, or a dictionary with keys set to a string
representation of the SI unit with which the differential (derivative)
is taken. For example, for a velocity differential on a positional
representation, the key would be ``'s'`` for seconds, indicating that
the derivative is a time derivative.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
Notes
-----
All representation classes should subclass this base representation class,
and define an ``attr_classes`` attribute, an `~collections.OrderedDict`
which maps component names to the class that creates them. They must also
define a ``to_cartesian`` method and a ``from_cartesian`` class method. By
default, transformations are done via the cartesian system, but classes
that want to define a smarter transformation path can overload the
``represent_as`` method. If one wants to use an associated differential
class, one should also define ``unit_vectors`` and ``scale_factors``
methods (see those methods for details).
"""
recommended_units = deprecated_attribute('recommended_units', since='3.0')
_recommended_units = {}
def __init__(self, *args, differentials=None, **kwargs):
# Handle any differentials passed in.
super().__init__(*args, **kwargs)
self._differentials = self._validate_differentials(differentials)
def _validate_differentials(self, differentials):
"""
Validate that the provided differentials are appropriate for this
representation and recast/reshape as necessary and then return.
Note that this does *not* set the differentials on
``self._differentials``, but rather leaves that for the caller.
"""
# Now handle the actual validation of any specified differential classes
if differentials is None:
differentials = dict()
elif isinstance(differentials, BaseDifferential):
# We can't handle auto-determining the key for this combo
if (isinstance(differentials, RadialDifferential) and
isinstance(self, UnitSphericalRepresentation)):
raise ValueError("To attach a RadialDifferential to a "
"UnitSphericalRepresentation, you must supply "
"a dictionary with an appropriate key.")
key = differentials._get_deriv_key(self)
differentials = {key: differentials}
for key in differentials:
try:
diff = differentials[key]
except TypeError:
raise TypeError("'differentials' argument must be a "
"dictionary-like object")
diff._check_base(self)
if (isinstance(diff, RadialDifferential) and
isinstance(self, UnitSphericalRepresentation)):
# We trust the passing of a key for a RadialDifferential
# attached to a UnitSphericalRepresentation because it will not
# have a paired component name (UnitSphericalRepresentation has
# no .distance) to automatically determine the expected key
pass
else:
expected_key = diff._get_deriv_key(self)
if key != expected_key:
raise ValueError("For differential object '{0}', expected "
"unit key = '{1}' but received key = '{2}'"
.format(repr(diff), expected_key, key))
# For now, we are very rigid: differentials must have the same shape
# as the representation. This makes it easier to handle __getitem__
# and any other shape-changing operations on representations that
# have associated differentials
if diff.shape != self.shape:
# TODO: message of IncompatibleShapeError is not customizable,
# so use a valueerror instead?
raise ValueError("Shape of differentials must be the same "
"as the shape of the representation ({0} vs "
"{1})".format(diff.shape, self.shape))
return differentials
def _raise_if_has_differentials(self, op_name):
"""
Used to raise a consistent exception for any operation that is not
supported when a representation has differentials attached.
"""
if self.differentials:
raise TypeError("Operation '{0}' is not supported when "
"differentials are attached to a {1}."
.format(op_name, self.__class__.__name__))
@property
def _compatible_differentials(self):
return [DIFFERENTIAL_CLASSES[self.get_name()]]
@property
def differentials(self):
"""A dictionary of differential class instances.
The keys of this dictionary must be a string representation of the SI
unit with which the differential (derivative) is taken. For example, for
a velocity differential on a positional representation, the key would be
``'s'`` for seconds, indicating that the derivative is a time
derivative.
"""
return self._differentials
# We do not make unit_vectors and scale_factors abstract methods, since
# they are only necessary if one also defines an associated Differential.
# Also, doing so would break pre-differential representation subclasses.
def unit_vectors(self):
r"""Cartesian unit vectors in the direction of each component.
Given unit vectors :math:`\hat{e}_c` and scale factors :math:`f_c`,
a change in one component of :math:`\delta c` corresponds to a change
in representation of :math:`\delta c \times f_c \times \hat{e}_c`.
Returns
-------
unit_vectors : dict of `CartesianRepresentation`
The keys are the component names.
"""
raise NotImplementedError("{} has not implemented unit vectors"
.format(type(self)))
def scale_factors(self):
r"""Scale factors for each component's direction.
Given unit vectors :math:`\hat{e}_c` and scale factors :math:`f_c`,
a change in one component of :math:`\delta c` corresponds to a change
in representation of :math:`\delta c \times f_c \times \hat{e}_c`.
Returns
-------
scale_factors : dict of `~astropy.units.Quantity`
The keys are the component names.
"""
raise NotImplementedError("{} has not implemented scale factors."
.format(type(self)))
def _re_represent_differentials(self, new_rep, differential_class):
"""Re-represent the differentials to the specified classes.
This returns a new dictionary with the same keys but with the
attached differentials converted to the new differential classes.
"""
if differential_class is None:
return dict()
if not self.differentials and differential_class:
raise ValueError("No differentials associated with this "
"representation!")
elif (len(self.differentials) == 1 and
inspect.isclass(differential_class) and
issubclass(differential_class, BaseDifferential)):
# TODO: is there a better way to do this?
differential_class = {
list(self.differentials.keys())[0]: differential_class
}
elif set(differential_class.keys()) != set(self.differentials.keys()):
ValueError("Desired differential classes must be passed in "
"as a dictionary with keys equal to a string "
"representation of the unit of the derivative "
"for each differential stored with this "
"representation object ({0})"
.format(self.differentials))
new_diffs = dict()
for k in self.differentials:
diff = self.differentials[k]
try:
new_diffs[k] = diff.represent_as(differential_class[k],
base=self)
except Exception:
if (differential_class[k] not in
new_rep._compatible_differentials):
raise TypeError("Desired differential class {0} is not "
"compatible with the desired "
"representation class {1}"
.format(differential_class[k],
new_rep.__class__))
else:
raise
return new_diffs
def represent_as(self, other_class, differential_class=None):
"""Convert coordinates to another representation.
If the instance is of the requested class, it is returned unmodified.
By default, conversion is done via cartesian coordinates.
Parameters
----------
other_class : `~astropy.coordinates.BaseRepresentation` subclass
The type of representation to turn the coordinates into.
differential_class : dict of `~astropy.coordinates.BaseDifferential`, optional
Classes in which the differentials should be represented.
Can be a single class if only a single differential is attached,
otherwise it should be a `dict` keyed by the same keys as the
differentials.
"""
if other_class is self.__class__ and not differential_class:
return self.without_differentials()
else:
if isinstance(other_class, str):
raise ValueError("Input to a representation's represent_as "
"must be a class, not a string. For "
"strings, use frame objects")
# The default is to convert via cartesian coordinates
new_rep = other_class.from_cartesian(self.to_cartesian())
new_rep._differentials = self._re_represent_differentials(
new_rep, differential_class)
return new_rep
def with_differentials(self, differentials):
"""
Create a new representation with the same positions as this
representation, but with these new differentials.
Differential keys that already exist in this object's differential dict
are overwritten.
Parameters
----------
differentials : Sequence of `~astropy.coordinates.BaseDifferential`
The differentials for the new representation to have.
Returns
-------
newrepr
A copy of this representation, but with the ``differentials`` as
its differentials.
"""
if not differentials:
return self
args = [getattr(self, component) for component in self.components]
# We shallow copy the differentials dictionary so we don't update the
# current object's dictionary when adding new keys
new_rep = self.__class__(*args, differentials=self.differentials.copy(),
copy=False)
new_rep._differentials.update(
new_rep._validate_differentials(differentials))
return new_rep
def without_differentials(self):
"""Return a copy of the representation without attached differentials.
Returns
-------
newrepr
A shallow copy of this representation, without any differentials.
If no differentials were present, no copy is made.
"""
if not self._differentials:
return self
args = [getattr(self, component) for component in self.components]
return self.__class__(*args, copy=False)
@classmethod
def from_representation(cls, representation):
"""Create a new instance of this representation from another one.
Parameters
----------
representation : `~astropy.coordinates.BaseRepresentation` instance
The presentation that should be converted to this class.
"""
return representation.represent_as(cls)
def _apply(self, method, *args, **kwargs):
"""Create a new representation with ``method`` applied to the component
data.
This is not a simple inherit from ``BaseRepresentationOrDifferential``
because we need to call ``._apply()`` on any associated differential
classes.
See docstring for `BaseRepresentationOrDifferential._apply`.
Parameters
----------
method : str or callable
If str, it is the name of a method that is applied to the internal
``components``. If callable, the function is applied.
args : tuple
Any positional arguments for ``method``.
kwargs : dict
Any keyword arguments for ``method``.
"""
rep = super()._apply(method, *args, **kwargs)
rep._differentials = dict(
[(k, diff._apply(method, *args, **kwargs))
for k, diff in self._differentials.items()])
return rep
def _scale_operation(self, op, *args):
"""Scale all non-angular components, leaving angular ones unchanged.
Parameters
----------
op : `~operator` callable
Operator to apply (e.g., `~operator.mul`, `~operator.neg`, etc.
*args
Any arguments required for the operator (typically, what is to
be multiplied with, divided by).
"""
self._raise_if_has_differentials(op.__name__)
results = []
for component, cls in self.attr_classes.items():
value = getattr(self, component)
if issubclass(cls, Angle):
results.append(value)
else:
results.append(op(value, *args))
# try/except catches anything that cannot initialize the class, such
# as operations that returned NotImplemented or a representation
# instead of a quantity (as would happen for, e.g., rep * rep).
try:
return self.__class__(*results)
except Exception:
return NotImplemented
def _combine_operation(self, op, other, reverse=False):
"""Combine two representation.
By default, operate on the cartesian representations of both.
Parameters
----------
op : `~operator` callable
Operator to apply (e.g., `~operator.add`, `~operator.sub`, etc.
other : `~astropy.coordinates.BaseRepresentation` instance
The other representation.
reverse : bool
Whether the operands should be reversed (e.g., as we got here via
``self.__rsub__`` because ``self`` is a subclass of ``other``).
"""
self._raise_if_has_differentials(op.__name__)
result = self.to_cartesian()._combine_operation(op, other, reverse)
if result is NotImplemented:
return NotImplemented
else:
return self.from_cartesian(result)
# We need to override this setter to support differentials
@BaseRepresentationOrDifferential.shape.setter
def shape(self, shape):
orig_shape = self.shape
# See: https://stackoverflow.com/questions/3336767/ for an example
BaseRepresentationOrDifferential.shape.fset(self, shape)
# also try to perform shape-setting on any associated differentials
try:
for k in self.differentials:
self.differentials[k].shape = shape
except Exception:
BaseRepresentationOrDifferential.shape.fset(self, orig_shape)
for k in self.differentials:
self.differentials[k].shape = orig_shape
raise
def norm(self):
"""Vector norm.
The norm is the standard Frobenius norm, i.e., the square root of the
sum of the squares of all components with non-angular units.
Note that any associated differentials will be dropped during this
operation.
Returns
-------
norm : `astropy.units.Quantity`
Vector norm, with the same shape as the representation.
"""
return np.sqrt(functools.reduce(
operator.add, (getattr(self, component)**2
for component, cls in self.attr_classes.items()
if not issubclass(cls, Angle))))
def mean(self, *args, **kwargs):
"""Vector mean.
Averaging is done by converting the representation to cartesian, and
taking the mean of the x, y, and z components. The result is converted
back to the same representation as the input.
Refer to `~numpy.mean` for full documentation of the arguments, noting
that ``axis`` is the entry in the ``shape`` of the representation, and
that the ``out`` argument cannot be used.
Returns
-------
mean : representation
Vector mean, in the same representation as that of the input.
"""
self._raise_if_has_differentials('mean')
return self.from_cartesian(self.to_cartesian().mean(*args, **kwargs))
def sum(self, *args, **kwargs):
"""Vector sum.
Adding is done by converting the representation to cartesian, and
summing the x, y, and z components. The result is converted back to the
same representation as the input.
Refer to `~numpy.sum` for full documentation of the arguments, noting
that ``axis`` is the entry in the ``shape`` of the representation, and
that the ``out`` argument cannot be used.
Returns
-------
sum : representation
Vector sum, in the same representation as that of the input.
"""
self._raise_if_has_differentials('sum')
return self.from_cartesian(self.to_cartesian().sum(*args, **kwargs))
def dot(self, other):
"""Dot product of two representations.
The calculation is done by converting both ``self`` and ``other``
to `~astropy.coordinates.CartesianRepresentation`.
Note that any associated differentials will be dropped during this
operation.
Parameters
----------
other : `~astropy.coordinates.BaseRepresentation`
The representation to take the dot product with.
Returns
-------
dot_product : `~astropy.units.Quantity`
The sum of the product of the x, y, and z components of the
cartesian representations of ``self`` and ``other``.
"""
return self.to_cartesian().dot(other)
def cross(self, other):
"""Vector cross product of two representations.
The calculation is done by converting both ``self`` and ``other``
to `~astropy.coordinates.CartesianRepresentation`, and converting the
result back to the type of representation of ``self``.
Parameters
----------
other : representation
The representation to take the cross product with.
Returns
-------
cross_product : representation
With vectors perpendicular to both ``self`` and ``other``, in the
same type of representation as ``self``.
"""
self._raise_if_has_differentials('cross')
return self.from_cartesian(self.to_cartesian().cross(other))
class CartesianRepresentation(BaseRepresentation):
"""
Representation of points in 3D cartesian coordinates.
Parameters
----------
x, y, z : `~astropy.units.Quantity` or array
The x, y, and z coordinates of the point(s). If ``x``, ``y``, and ``z``
have different shapes, they should be broadcastable. If not quantity,
``unit`` should be set. If only ``x`` is given, it is assumed that it
contains an array with the 3 coordinates stored along ``xyz_axis``.
unit : `~astropy.units.Unit` or str
If given, the coordinates will be converted to this unit (or taken to
be in this unit if not given.
xyz_axis : int, optional
The axis along which the coordinates are stored when a single array is
provided rather than distinct ``x``, ``y``, and ``z`` (default: 0).
differentials : dict, `CartesianDifferential`, optional
Any differential classes that should be associated with this
representation. The input must either be a single
`CartesianDifferential` instance, or a dictionary of
`CartesianDifferential` s with keys set to a string representation of
the SI unit with which the differential (derivative) is taken. For
example, for a velocity differential on a positional representation, the
key would be ``'s'`` for seconds, indicating that the derivative is a
time derivative.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
attr_classes = OrderedDict([('x', u.Quantity),
('y', u.Quantity),
('z', u.Quantity)])
def __init__(self, x, y=None, z=None, unit=None, xyz_axis=None,
differentials=None, copy=True):
if y is None and z is None:
if xyz_axis is not None and xyz_axis != 0:
x = np.rollaxis(x, xyz_axis, 0)
x, y, z = x
elif xyz_axis is not None:
raise ValueError("xyz_axis should only be set if x, y, and z are "
"in a single array passed in through x, "
"i.e., y and z should not be not given.")
elif (y is None and z is not None) or (y is not None and z is None):
raise ValueError("x, y, and z are required to instantiate {0}"
.format(self.__class__.__name__))
if unit is not None:
x = u.Quantity(x, unit, copy=copy, subok=True)
y = u.Quantity(y, unit, copy=copy, subok=True)
z = u.Quantity(z, unit, copy=copy, subok=True)
copy = False
super().__init__(x, y, z, copy=copy, differentials=differentials)
if not (self._x.unit.physical_type ==
self._y.unit.physical_type == self._z.unit.physical_type):
raise u.UnitsError("x, y, and z should have matching physical types")
def unit_vectors(self):
l = np.broadcast_to(1.*u.one, self.shape, subok=True)
o = np.broadcast_to(0.*u.one, self.shape, subok=True)
return OrderedDict(
(('x', CartesianRepresentation(l, o, o, copy=False)),
('y', CartesianRepresentation(o, l, o, copy=False)),
('z', CartesianRepresentation(o, o, l, copy=False))))
def scale_factors(self):
l = np.broadcast_to(1.*u.one, self.shape, subok=True)
return OrderedDict((('x', l), ('y', l), ('z', l)))
def get_xyz(self, xyz_axis=0):
"""Return a vector array of the x, y, and z coordinates.
Parameters
----------
xyz_axis : int, optional
The axis in the final array along which the x, y, z components
should be stored (default: 0).
Returns
-------
xyz : `~astropy.units.Quantity`
With dimension 3 along ``xyz_axis``.
"""
return _combine_xyz(self._x, self._y, self._z, xyz_axis=xyz_axis)
xyz = property(get_xyz)
@classmethod
def from_cartesian(cls, other):
return other
def to_cartesian(self):
return self
def transform(self, matrix):
"""
Transform the cartesian coordinates using a 3x3 matrix.
This returns a new representation and does not modify the original one.
Any differentials attached to this representation will also be
transformed.
Parameters
----------
matrix : `~numpy.ndarray`
A 3x3 transformation matrix, such as a rotation matrix.
Examples
--------
We can start off by creating a cartesian representation object:
>>> from astropy import units as u
>>> from astropy.coordinates import CartesianRepresentation
>>> rep = CartesianRepresentation([1, 2] * u.pc,
... [2, 3] * u.pc,
... [3, 4] * u.pc)
We now create a rotation matrix around the z axis:
>>> from astropy.coordinates.matrix_utilities import rotation_matrix
>>> rotation = rotation_matrix(30 * u.deg, axis='z')
Finally, we can apply this transformation:
>>> rep_new = rep.transform(rotation)
>>> rep_new.xyz # doctest: +FLOAT_CMP
<Quantity [[ 1.8660254 , 3.23205081],
[ 1.23205081, 1.59807621],
[ 3. , 4. ]] pc>
"""
# Avoid doing gratuitous np.array for things that look like arrays.
try:
matrix_shape = matrix.shape
except AttributeError:
matrix = np.array(matrix)
matrix_shape = matrix.shape
if matrix_shape[-2:] != (3, 3):
raise ValueError("tried to do matrix multiplication with an array "
"that doesn't end in 3x3")
# TODO: since this is likely to be a widely used function in coordinate
# transforms, it should be optimized (for example in Cython).
# Get xyz once since it's an expensive operation
oldxyz = self.xyz
# Note that neither dot nor einsum handles Quantity properly, so we use
# the arrays and put the unit back in the end.
if self.isscalar and not matrix_shape[:-2]:
# a fast path for scalar coordinates.
newxyz = matrix.dot(oldxyz.value)
else:
# Matrix multiply all pmat items and coordinates, broadcasting the
# remaining dimensions.
if np.__version__ == '1.14.0':
# there is a bug in numpy v1.14.0 (fixed in 1.14.1) that causes
# this einsum call to break with the default of optimize=True
# see https://github.com/astropy/astropy/issues/7051
newxyz = np.einsum('...ij,j...->i...', matrix, oldxyz.value,
optimize=False)
else:
newxyz = np.einsum('...ij,j...->i...', matrix, oldxyz.value)
newxyz = u.Quantity(newxyz, oldxyz.unit, copy=False)
# Handle differentials attached to this representation
if self.differentials:
# TODO: speed this up going via d.d_xyz.
new_diffs = dict(
(k, d.from_cartesian(d.to_cartesian().transform(matrix)))
for k, d in self.differentials.items())
else:
new_diffs = None
return self.__class__(*newxyz, copy=False, differentials=new_diffs)
def _combine_operation(self, op, other, reverse=False):
self._raise_if_has_differentials(op.__name__)
try:
other_c = other.to_cartesian()
except Exception:
return NotImplemented
first, second = ((self, other_c) if not reverse else
(other_c, self))
return self.__class__(*(op(getattr(first, component),
getattr(second, component))
for component in first.components))
def mean(self, *args, **kwargs):
"""Vector mean.
Returns a new CartesianRepresentation instance with the means of the
x, y, and z components.
Refer to `~numpy.mean` for full documentation of the arguments, noting
that ``axis`` is the entry in the ``shape`` of the representation, and
that the ``out`` argument cannot be used.
"""
self._raise_if_has_differentials('mean')
return self._apply('mean', *args, **kwargs)
def sum(self, *args, **kwargs):
"""Vector sum.
Returns a new CartesianRepresentation instance with the sums of the
x, y, and z components.
Refer to `~numpy.sum` for full documentation of the arguments, noting
that ``axis`` is the entry in the ``shape`` of the representation, and
that the ``out`` argument cannot be used.
"""
self._raise_if_has_differentials('sum')
return self._apply('sum', *args, **kwargs)
def dot(self, other):
"""Dot product of two representations.
Note that any associated differentials will be dropped during this
operation.
Parameters
----------
other : representation
If not already cartesian, it is converted.
Returns
-------
dot_product : `~astropy.units.Quantity`
The sum of the product of the x, y, and z components of ``self``
and ``other``.
"""
try:
other_c = other.to_cartesian()
except Exception:
raise TypeError("cannot only take dot product with another "
"representation, not a {0} instance."
.format(type(other)))
return functools.reduce(operator.add,
(getattr(self, component) *
getattr(other_c, component)
for component in self.components))
def cross(self, other):
"""Cross product of two representations.
Parameters
----------
other : representation
If not already cartesian, it is converted.
Returns
-------
cross_product : `~astropy.coordinates.CartesianRepresentation`
With vectors perpendicular to both ``self`` and ``other``.
"""
self._raise_if_has_differentials('cross')
try:
other_c = other.to_cartesian()
except Exception:
raise TypeError("cannot only take cross product with another "
"representation, not a {0} instance."
.format(type(other)))
return self.__class__(self.y * other_c.z - self.z * other_c.y,
self.z * other_c.x - self.x * other_c.z,
self.x * other_c.y - self.y * other_c.x)
class UnitSphericalRepresentation(BaseRepresentation):
"""
Representation of points on a unit sphere.
Parameters
----------
lon, lat : `~astropy.units.Quantity` or str
The longitude and latitude of the point(s), in angular units. The
latitude should be between -90 and 90 degrees, and the longitude will
be wrapped to an angle between 0 and 360 degrees. These can also be
instances of `~astropy.coordinates.Angle`,
`~astropy.coordinates.Longitude`, or `~astropy.coordinates.Latitude`.
differentials : dict, `BaseDifferential`, optional
Any differential classes that should be associated with this
representation. The input must either be a single `BaseDifferential`
instance (see `._compatible_differentials` for valid types), or a
dictionary of of differential instances with keys set to a string
representation of the SI unit with which the differential (derivative)
is taken. For example, for a velocity differential on a positional
representation, the key would be ``'s'`` for seconds, indicating that
the derivative is a time derivative.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
attr_classes = OrderedDict([('lon', Longitude),
('lat', Latitude)])
@classproperty
def _dimensional_representation(cls):
return SphericalRepresentation
def __init__(self, lon, lat, differentials=None, copy=True):
super().__init__(lon, lat, differentials=differentials, copy=copy)
@property
def _compatible_differentials(self):
return [UnitSphericalDifferential, UnitSphericalCosLatDifferential,
SphericalDifferential, SphericalCosLatDifferential,
RadialDifferential]
# Could let the metaclass define these automatically, but good to have
# a bit clearer docstrings.
@property
def lon(self):
"""
The longitude of the point(s).
"""
return self._lon
@property
def lat(self):
"""
The latitude of the point(s).
"""
return self._lat
def unit_vectors(self):
sinlon, coslon = np.sin(self.lon), np.cos(self.lon)
sinlat, coslat = np.sin(self.lat), np.cos(self.lat)
return OrderedDict(
(('lon', CartesianRepresentation(-sinlon, coslon, 0., copy=False)),
('lat', CartesianRepresentation(-sinlat*coslon, -sinlat*sinlon,
coslat, copy=False))))
def scale_factors(self, omit_coslat=False):
sf_lat = np.broadcast_to(1./u.radian, self.shape, subok=True)
sf_lon = sf_lat if omit_coslat else np.cos(self.lat) / u.radian
return OrderedDict((('lon', sf_lon),
('lat', sf_lat)))
def to_cartesian(self):
"""
Converts spherical polar coordinates to 3D rectangular cartesian
coordinates.
"""
x = np.cos(self.lat) * np.cos(self.lon)
y = np.cos(self.lat) * np.sin(self.lon)
z = np.sin(self.lat)
return CartesianRepresentation(x=x, y=y, z=z, copy=False)
@classmethod
def from_cartesian(cls, cart):
"""
Converts 3D rectangular cartesian coordinates to spherical polar
coordinates.
"""
s = np.hypot(cart.x, cart.y)
lon = np.arctan2(cart.y, cart.x)
lat = np.arctan2(cart.z, s)
return cls(lon=lon, lat=lat, copy=False)
def represent_as(self, other_class, differential_class=None):
# Take a short cut if the other class is a spherical representation
# TODO: this could be optimized to shortcut even if a differential_class
# is passed in, using the ._re_represent_differentials() method
if inspect.isclass(other_class) and not differential_class:
if issubclass(other_class, PhysicsSphericalRepresentation):
return other_class(phi=self.lon, theta=90 * u.deg - self.lat, r=1.0,
copy=False)
elif issubclass(other_class, SphericalRepresentation):
return other_class(lon=self.lon, lat=self.lat, distance=1.0,
copy=False)
return super().represent_as(other_class, differential_class)
def __mul__(self, other):
self._raise_if_has_differentials('multiplication')
return self._dimensional_representation(lon=self.lon, lat=self.lat,
distance=1. * other)
def __truediv__(self, other):
self._raise_if_has_differentials('division')
return self._dimensional_representation(lon=self.lon, lat=self.lat,
distance=1. / other)
def __neg__(self):
self._raise_if_has_differentials('negation')
return self.__class__(self.lon + 180. * u.deg, -self.lat, copy=False)
def norm(self):
"""Vector norm.
The norm is the standard Frobenius norm, i.e., the square root of the
sum of the squares of all components with non-angular units, which is
always unity for vectors on the unit sphere.
Returns
-------
norm : `~astropy.units.Quantity`
Dimensionless ones, with the same shape as the representation.
"""
return u.Quantity(np.ones(self.shape), u.dimensionless_unscaled,
copy=False)
def _combine_operation(self, op, other, reverse=False):
self._raise_if_has_differentials(op.__name__)
result = self.to_cartesian()._combine_operation(op, other, reverse)
if result is NotImplemented:
return NotImplemented
else:
return self._dimensional_representation.from_cartesian(result)
def mean(self, *args, **kwargs):
"""Vector mean.
The representation is converted to cartesian, the means of the x, y,
and z components are calculated, and the result is converted to a
`~astropy.coordinates.SphericalRepresentation`.
Refer to `~numpy.mean` for full documentation of the arguments, noting
that ``axis`` is the entry in the ``shape`` of the representation, and
that the ``out`` argument cannot be used.
"""
self._raise_if_has_differentials('mean')
return self._dimensional_representation.from_cartesian(
self.to_cartesian().mean(*args, **kwargs))
def sum(self, *args, **kwargs):
"""Vector sum.
The representation is converted to cartesian, the sums of the x, y,
and z components are calculated, and the result is converted to a
`~astropy.coordinates.SphericalRepresentation`.
Refer to `~numpy.sum` for full documentation of the arguments, noting
that ``axis`` is the entry in the ``shape`` of the representation, and
that the ``out`` argument cannot be used.
"""
self._raise_if_has_differentials('sum')
return self._dimensional_representation.from_cartesian(
self.to_cartesian().sum(*args, **kwargs))
def cross(self, other):
"""Cross product of two representations.
The calculation is done by converting both ``self`` and ``other``
to `~astropy.coordinates.CartesianRepresentation`, and converting the
result back to `~astropy.coordinates.SphericalRepresentation`.
Parameters
----------
other : representation
The representation to take the cross product with.
Returns
-------
cross_product : `~astropy.coordinates.SphericalRepresentation`
With vectors perpendicular to both ``self`` and ``other``.
"""
self._raise_if_has_differentials('cross')
return self._dimensional_representation.from_cartesian(
self.to_cartesian().cross(other))
class RadialRepresentation(BaseRepresentation):
"""
Representation of the distance of points from the origin.
Note that this is mostly intended as an internal helper representation.
It can do little else but being used as a scale in multiplication.
Parameters
----------
distance : `~astropy.units.Quantity`
The distance of the point(s) from the origin.
differentials : dict, `BaseDifferential`, optional
Any differential classes that should be associated with this
representation. The input must either be a single `BaseDifferential`
instance (see `._compatible_differentials` for valid types), or a
dictionary of of differential instances with keys set to a string
representation of the SI unit with which the differential (derivative)
is taken. For example, for a velocity differential on a positional
representation, the key would be ``'s'`` for seconds, indicating that
the derivative is a time derivative.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
attr_classes = OrderedDict([('distance', u.Quantity)])
def __init__(self, distance, differentials=None, copy=True):
super().__init__(distance, copy=copy, differentials=differentials)
@property
def distance(self):
"""
The distance from the origin to the point(s).
"""
return self._distance
def unit_vectors(self):
"""Cartesian unit vectors are undefined for radial representation."""
raise NotImplementedError('Cartesian unit vectors are undefined for '
'{0} instances'.format(self.__class__))
def scale_factors(self):
l = np.broadcast_to(1.*u.one, self.shape, subok=True)
return OrderedDict((('distance', l),))
def to_cartesian(self):
"""Cannot convert radial representation to cartesian."""
raise NotImplementedError('cannot convert {0} instance to cartesian.'
.format(self.__class__))
@classmethod
def from_cartesian(cls, cart):
"""
Converts 3D rectangular cartesian coordinates to radial coordinate.
"""
return cls(distance=cart.norm(), copy=False)
def _scale_operation(self, op, *args):
self._raise_if_has_differentials(op.__name__)
return op(self.distance, *args)
def norm(self):
"""Vector norm.
Just the distance itself.
Returns
-------
norm : `~astropy.units.Quantity`
Dimensionless ones, with the same shape as the representation.
"""
return self.distance
def _combine_operation(self, op, other, reverse=False):
return NotImplemented
class SphericalRepresentation(BaseRepresentation):
"""
Representation of points in 3D spherical coordinates.
Parameters
----------
lon, lat : `~astropy.units.Quantity`
The longitude and latitude of the point(s), in angular units. The
latitude should be between -90 and 90 degrees, and the longitude will
be wrapped to an angle between 0 and 360 degrees. These can also be
instances of `~astropy.coordinates.Angle`,
`~astropy.coordinates.Longitude`, or `~astropy.coordinates.Latitude`.
distance : `~astropy.units.Quantity`
The distance to the point(s). If the distance is a length, it is
passed to the :class:`~astropy.coordinates.Distance` class, otherwise
it is passed to the :class:`~astropy.units.Quantity` class.
differentials : dict, `BaseDifferential`, optional
Any differential classes that should be associated with this
representation. The input must either be a single `BaseDifferential`
instance (see `._compatible_differentials` for valid types), or a
dictionary of of differential instances with keys set to a string
representation of the SI unit with which the differential (derivative)
is taken. For example, for a velocity differential on a positional
representation, the key would be ``'s'`` for seconds, indicating that
the derivative is a time derivative.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
attr_classes = OrderedDict([('lon', Longitude),
('lat', Latitude),
('distance', u.Quantity)])
_unit_representation = UnitSphericalRepresentation
def __init__(self, lon, lat, distance, differentials=None, copy=True):
super().__init__(lon, lat, distance, copy=copy,
differentials=differentials)
if self._distance.unit.physical_type == 'length':
self._distance = self._distance.view(Distance)
@property
def _compatible_differentials(self):
return [UnitSphericalDifferential, UnitSphericalCosLatDifferential,
SphericalDifferential, SphericalCosLatDifferential,
RadialDifferential]
@property
def lon(self):
"""
The longitude of the point(s).
"""
return self._lon
@property
def lat(self):
"""
The latitude of the point(s).
"""
return self._lat
@property
def distance(self):
"""
The distance from the origin to the point(s).
"""
return self._distance
def unit_vectors(self):
sinlon, coslon = np.sin(self.lon), np.cos(self.lon)
sinlat, coslat = np.sin(self.lat), np.cos(self.lat)
return OrderedDict(
(('lon', CartesianRepresentation(-sinlon, coslon, 0., copy=False)),
('lat', CartesianRepresentation(-sinlat*coslon, -sinlat*sinlon,
coslat, copy=False)),
('distance', CartesianRepresentation(coslat*coslon, coslat*sinlon,
sinlat, copy=False))))
def scale_factors(self, omit_coslat=False):
sf_lat = self.distance / u.radian
sf_lon = sf_lat if omit_coslat else sf_lat * np.cos(self.lat)
sf_distance = np.broadcast_to(1.*u.one, self.shape, subok=True)
return OrderedDict((('lon', sf_lon),
('lat', sf_lat),
('distance', sf_distance)))
def represent_as(self, other_class, differential_class=None):
# Take a short cut if the other class is a spherical representation
# TODO: this could be optimized to shortcut even if a differential_class
# is passed in, using the ._re_represent_differentials() method
if inspect.isclass(other_class) and not differential_class:
if issubclass(other_class, PhysicsSphericalRepresentation):
return other_class(phi=self.lon, theta=90 * u.deg - self.lat,
r=self.distance, copy=False)
elif issubclass(other_class, UnitSphericalRepresentation):
return other_class(lon=self.lon, lat=self.lat, copy=False)
return super().represent_as(other_class, differential_class)
def to_cartesian(self):
"""
Converts spherical polar coordinates to 3D rectangular cartesian
coordinates.
"""
# We need to convert Distance to Quantity to allow negative values.
if isinstance(self.distance, Distance):
d = self.distance.view(u.Quantity)
else:
d = self.distance
x = d * np.cos(self.lat) * np.cos(self.lon)
y = d * np.cos(self.lat) * np.sin(self.lon)
z = d * np.sin(self.lat)
return CartesianRepresentation(x=x, y=y, z=z, copy=False)
@classmethod
def from_cartesian(cls, cart):
"""
Converts 3D rectangular cartesian coordinates to spherical polar
coordinates.
"""
s = np.hypot(cart.x, cart.y)
r = np.hypot(s, cart.z)
lon = np.arctan2(cart.y, cart.x)
lat = np.arctan2(cart.z, s)
return cls(lon=lon, lat=lat, distance=r, copy=False)
def norm(self):
"""Vector norm.
The norm is the standard Frobenius norm, i.e., the square root of the
sum of the squares of all components with non-angular units. For
spherical coordinates, this is just the absolute value of the distance.
Returns
-------
norm : `astropy.units.Quantity`
Vector norm, with the same shape as the representation.
"""
return np.abs(self.distance)
class PhysicsSphericalRepresentation(BaseRepresentation):
"""
Representation of points in 3D spherical coordinates (using the physics
convention of using ``phi`` and ``theta`` for azimuth and inclination
from the pole).
Parameters
----------
phi, theta : `~astropy.units.Quantity` or str
The azimuth and inclination of the point(s), in angular units. The
inclination should be between 0 and 180 degrees, and the azimuth will
be wrapped to an angle between 0 and 360 degrees. These can also be
instances of `~astropy.coordinates.Angle`. If ``copy`` is False, `phi`
will be changed inplace if it is not between 0 and 360 degrees.
r : `~astropy.units.Quantity`
The distance to the point(s). If the distance is a length, it is
passed to the :class:`~astropy.coordinates.Distance` class, otherwise
it is passed to the :class:`~astropy.units.Quantity` class.
differentials : dict, `PhysicsSphericalDifferential`, optional
Any differential classes that should be associated with this
representation. The input must either be a single
`PhysicsSphericalDifferential` instance, or a dictionary of of
differential instances with keys set to a string representation of the
SI unit with which the differential (derivative) is taken. For example,
for a velocity differential on a positional representation, the key
would be ``'s'`` for seconds, indicating that the derivative is a time
derivative.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
attr_classes = OrderedDict([('phi', Angle),
('theta', Angle),
('r', u.Quantity)])
def __init__(self, phi, theta, r, differentials=None, copy=True):
super().__init__(phi, theta, r, copy=copy, differentials=differentials)
# Wrap/validate phi/theta
if copy:
self._phi = self._phi.wrap_at(360 * u.deg)
else:
# necessary because the above version of `wrap_at` has to be a copy
self._phi.wrap_at(360 * u.deg, inplace=True)
if np.any(self._theta < 0.*u.deg) or np.any(self._theta > 180.*u.deg):
raise ValueError('Inclination angle(s) must be within '
'0 deg <= angle <= 180 deg, '
'got {0}'.format(theta.to(u.degree)))
if self._r.unit.physical_type == 'length':
self._r = self._r.view(Distance)
@property
def phi(self):
"""
The azimuth of the point(s).
"""
return self._phi
@property
def theta(self):
"""
The elevation of the point(s).
"""
return self._theta
@property
def r(self):
"""
The distance from the origin to the point(s).
"""
return self._r
def unit_vectors(self):
sinphi, cosphi = np.sin(self.phi), np.cos(self.phi)
sintheta, costheta = np.sin(self.theta), np.cos(self.theta)
return OrderedDict(
(('phi', CartesianRepresentation(-sinphi, cosphi, 0., copy=False)),
('theta', CartesianRepresentation(costheta*cosphi,
costheta*sinphi,
-sintheta, copy=False)),
('r', CartesianRepresentation(sintheta*cosphi, sintheta*sinphi,
costheta, copy=False))))
def scale_factors(self):
r = self.r / u.radian
sintheta = np.sin(self.theta)
l = np.broadcast_to(1.*u.one, self.shape, subok=True)
return OrderedDict((('phi', r * sintheta),
('theta', r),
('r', l)))
def represent_as(self, other_class, differential_class=None):
# Take a short cut if the other class is a spherical representation
# TODO: this could be optimized to shortcut even if a differential_class
# is passed in, using the ._re_represent_differentials() method
if inspect.isclass(other_class) and not differential_class:
if issubclass(other_class, SphericalRepresentation):
return other_class(lon=self.phi, lat=90 * u.deg - self.theta,
distance=self.r)
elif issubclass(other_class, UnitSphericalRepresentation):
return other_class(lon=self.phi, lat=90 * u.deg - self.theta)
return super().represent_as(other_class, differential_class)
def to_cartesian(self):
"""
Converts spherical polar coordinates to 3D rectangular cartesian
coordinates.
"""
# We need to convert Distance to Quantity to allow negative values.
if isinstance(self.r, Distance):
d = self.r.view(u.Quantity)
else:
d = self.r
x = d * np.sin(self.theta) * np.cos(self.phi)
y = d * np.sin(self.theta) * np.sin(self.phi)
z = d * np.cos(self.theta)
return CartesianRepresentation(x=x, y=y, z=z, copy=False)
@classmethod
def from_cartesian(cls, cart):
"""
Converts 3D rectangular cartesian coordinates to spherical polar
coordinates.
"""
s = np.hypot(cart.x, cart.y)
r = np.hypot(s, cart.z)
phi = np.arctan2(cart.y, cart.x)
theta = np.arctan2(s, cart.z)
return cls(phi=phi, theta=theta, r=r, copy=False)
def norm(self):
"""Vector norm.
The norm is the standard Frobenius norm, i.e., the square root of the
sum of the squares of all components with non-angular units. For
spherical coordinates, this is just the absolute value of the radius.
Returns
-------
norm : `astropy.units.Quantity`
Vector norm, with the same shape as the representation.
"""
return np.abs(self.r)
class CylindricalRepresentation(BaseRepresentation):
"""
Representation of points in 3D cylindrical coordinates.
Parameters
----------
rho : `~astropy.units.Quantity`
The distance from the z axis to the point(s).
phi : `~astropy.units.Quantity` or str
The azimuth of the point(s), in angular units, which will be wrapped
to an angle between 0 and 360 degrees. This can also be instances of
`~astropy.coordinates.Angle`,
z : `~astropy.units.Quantity`
The z coordinate(s) of the point(s)
differentials : dict, `CylindricalDifferential`, optional
Any differential classes that should be associated with this
representation. The input must either be a single
`CylindricalDifferential` instance, or a dictionary of of differential
instances with keys set to a string representation of the SI unit with
which the differential (derivative) is taken. For example, for a
velocity differential on a positional representation, the key would be
``'s'`` for seconds, indicating that the derivative is a time
derivative.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
attr_classes = OrderedDict([('rho', u.Quantity),
('phi', Angle),
('z', u.Quantity)])
def __init__(self, rho, phi, z, differentials=None, copy=True):
super().__init__(rho, phi, z, copy=copy, differentials=differentials)
if not self._rho.unit.is_equivalent(self._z.unit):
raise u.UnitsError("rho and z should have matching physical types")
@property
def rho(self):
"""
The distance of the point(s) from the z-axis.
"""
return self._rho
@property
def phi(self):
"""
The azimuth of the point(s).
"""
return self._phi
@property
def z(self):
"""
The height of the point(s).
"""
return self._z
def unit_vectors(self):
sinphi, cosphi = np.sin(self.phi), np.cos(self.phi)
l = np.broadcast_to(1., self.shape)
return OrderedDict(
(('rho', CartesianRepresentation(cosphi, sinphi, 0, copy=False)),
('phi', CartesianRepresentation(-sinphi, cosphi, 0, copy=False)),
('z', CartesianRepresentation(0, 0, l, unit=u.one, copy=False))))
def scale_factors(self):
rho = self.rho / u.radian
l = np.broadcast_to(1.*u.one, self.shape, subok=True)
return OrderedDict((('rho', l),
('phi', rho),
('z', l)))
@classmethod
def from_cartesian(cls, cart):
"""
Converts 3D rectangular cartesian coordinates to cylindrical polar
coordinates.
"""
rho = np.hypot(cart.x, cart.y)
phi = np.arctan2(cart.y, cart.x)
z = cart.z
return cls(rho=rho, phi=phi, z=z, copy=False)
def to_cartesian(self):
"""
Converts cylindrical polar coordinates to 3D rectangular cartesian
coordinates.
"""
x = self.rho * np.cos(self.phi)
y = self.rho * np.sin(self.phi)
z = self.z
return CartesianRepresentation(x=x, y=y, z=z, copy=False)
class MetaBaseDifferential(InheritDocstrings, abc.ABCMeta):
"""Set default ``attr_classes`` and component getters on a Differential.
For these, the components are those of the base representation prefixed
by 'd_', and the class is `~astropy.units.Quantity`.
"""
def __init__(cls, name, bases, dct):
super().__init__(name, bases, dct)
# Don't do anything for base helper classes.
if cls.__name__ in ('BaseDifferential', 'BaseSphericalDifferential',
'BaseSphericalCosLatDifferential'):
return
if 'base_representation' not in dct:
raise NotImplementedError('Differential representations must have a'
'"base_representation" class attribute.')
# If not defined explicitly, create attr_classes.
if not hasattr(cls, 'attr_classes'):
base_attr_classes = cls.base_representation.attr_classes
cls.attr_classes = OrderedDict([('d_' + c, u.Quantity)
for c in base_attr_classes])
if 'recommended_units' in dct:
warnings.warn(_recommended_units_deprecation,
AstropyDeprecationWarning)
# Ensure we don't override the property that warns about the
# deprecation, but that the value remains the same.
dct.setdefault('_recommended_units', dct.pop('recommended_units'))
repr_name = cls.get_name()
if repr_name in DIFFERENTIAL_CLASSES:
raise ValueError("Differential class {0} already defined"
.format(repr_name))
DIFFERENTIAL_CLASSES[repr_name] = cls
# If not defined explicitly, create properties for the components.
for component in cls.attr_classes:
if not hasattr(cls, component):
setattr(cls, component,
property(_make_getter(component),
doc=("Component '{0}' of the Differential."
.format(component))))
class BaseDifferential(BaseRepresentationOrDifferential,
metaclass=MetaBaseDifferential):
r"""A base class representing differentials of representations.
These represent differences or derivatives along each component.
E.g., for physics spherical coordinates, these would be
:math:`\delta r, \delta \theta, \delta \phi`.
Parameters
----------
d_comp1, d_comp2, d_comp3 : `~astropy.units.Quantity` or subclass
The components of the 3D differentials. The names are the keys and the
subclasses the values of the ``attr_classes`` attribute.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
Notes
-----
All differential representation classes should subclass this base class,
and define an ``base_representation`` attribute with the class of the
regular `~astropy.coordinates.BaseRepresentation` for which differential
coordinates are provided. This will set up a default ``attr_classes``
instance with names equal to the base component names prefixed by ``d_``,
and all classes set to `~astropy.units.Quantity`, plus properties to access
those, and a default ``__init__`` for initialization.
"""
recommended_units = deprecated_attribute('recommended_units', since='3.0')
_recommended_units = {}
@classmethod
def _check_base(cls, base):
if cls not in base._compatible_differentials:
raise TypeError("Differential class {0} is not compatible with the "
"base (representation) class {1}"
.format(cls, base.__class__))
def _get_deriv_key(self, base):
"""Given a base (representation instance), determine the unit of the
derivative by removing the representation unit from the component units
of this differential.
"""
# This check is just a last resort so we don't return a strange unit key
# from accidentally passing in the wrong base.
self._check_base(base)
for name in base.components:
comp = getattr(base, name)
d_comp = getattr(self, 'd_{0}'.format(name), None)
if d_comp is not None:
d_unit = comp.unit / d_comp.unit
# Get the si unit without a scale by going via Quantity;
# `.si` causes the scale to be included in the value.
return str(u.Quantity(1., d_unit).si.unit)
else:
raise RuntimeError("Invalid representation-differential match! Not "
"sure how we got into this state.")
@classmethod
def _get_base_vectors(cls, base):
"""Get unit vectors and scale factors from base.
Parameters
----------
base : instance of ``self.base_representation``
The points for which the unit vectors and scale factors should be
retrieved.
Returns
-------
unit_vectors : dict of `CartesianRepresentation`
In the directions of the coordinates of base.
scale_factors : dict of `~astropy.units.Quantity`
Scale factors for each of the coordinates
Raises
------
TypeError : if the base is not of the correct type
"""
cls._check_base(base)
return base.unit_vectors(), base.scale_factors()
def to_cartesian(self, base):
"""Convert the differential to 3D rectangular cartesian coordinates.
Parameters
----------
base : instance of ``self.base_representation``
The points for which the differentials are to be converted: each of
the components is multiplied by its unit vectors and scale factors.
Returns
-------
This object as a `CartesianDifferential`
"""
base_e, base_sf = self._get_base_vectors(base)
return functools.reduce(
operator.add, (getattr(self, d_c) * base_sf[c] * base_e[c]
for d_c, c in zip(self.components, base.components)))
@classmethod
def from_cartesian(cls, other, base):
"""Convert the differential from 3D rectangular cartesian coordinates to
the desired class.
Parameters
----------
other :
The object to convert into this differential.
base : instance of ``self.base_representation``
The points for which the differentials are to be converted: each of
the components is multiplied by its unit vectors and scale factors.
Returns
-------
A new differential object that is this class' type.
"""
base_e, base_sf = cls._get_base_vectors(base)
return cls(*(other.dot(e / base_sf[component])
for component, e in base_e.items()), copy=False)
def represent_as(self, other_class, base):
"""Convert coordinates to another representation.
If the instance is of the requested class, it is returned unmodified.
By default, conversion is done via cartesian coordinates.
Parameters
----------
other_class : `~astropy.coordinates.BaseRepresentation` subclass
The type of representation to turn the coordinates into.
base : instance of ``self.base_representation``, optional
Base relative to which the differentials are defined. If the other
class is a differential representation, the base will be converted
to its ``base_representation``.
"""
if other_class is self.__class__:
return self
# The default is to convert via cartesian coordinates.
self_cartesian = self.to_cartesian(base)
if issubclass(other_class, BaseDifferential):
base = base.represent_as(other_class.base_representation)
return other_class.from_cartesian(self_cartesian, base)
else:
return other_class.from_cartesian(self_cartesian)
@classmethod
def from_representation(cls, representation, base):
"""Create a new instance of this representation from another one.
Parameters
----------
representation : `~astropy.coordinates.BaseRepresentation` instance
The presentation that should be converted to this class.
base : instance of ``cls.base_representation``
The base relative to which the differentials will be defined. If
the representation is a differential itself, the base will be
converted to its ``base_representation`` to help convert it.
"""
if isinstance(representation, BaseDifferential):
cartesian = representation.to_cartesian(
base.represent_as(representation.base_representation))
else:
cartesian = representation.to_cartesian()
return cls.from_cartesian(cartesian, base)
def _scale_operation(self, op, *args):
"""Scale all components.
Parameters
----------
op : `~operator` callable
Operator to apply (e.g., `~operator.mul`, `~operator.neg`, etc.
*args
Any arguments required for the operator (typically, what is to
be multiplied with, divided by).
"""
scaled_attrs = [op(getattr(self, c), *args) for c in self.components]
return self.__class__(*scaled_attrs, copy=False)
def _combine_operation(self, op, other, reverse=False):
"""Combine two differentials, or a differential with a representation.
If ``other`` is of the same differential type as ``self``, the
components will simply be combined. If ``other`` is a representation,
it will be used as a base for which to evaluate the differential,
and the result is a new representation.
Parameters
----------
op : `~operator` callable
Operator to apply (e.g., `~operator.add`, `~operator.sub`, etc.
other : `~astropy.coordinates.BaseRepresentation` instance
The other differential or representation.
reverse : bool
Whether the operands should be reversed (e.g., as we got here via
``self.__rsub__`` because ``self`` is a subclass of ``other``).
"""
if isinstance(self, type(other)):
first, second = (self, other) if not reverse else (other, self)
return self.__class__(*[op(getattr(first, c), getattr(second, c))
for c in self.components])
else:
try:
self_cartesian = self.to_cartesian(other)
except TypeError:
return NotImplemented
return other._combine_operation(op, self_cartesian, not reverse)
def __sub__(self, other):
# avoid "differential - representation".
if isinstance(other, BaseRepresentation):
return NotImplemented
return super().__sub__(other)
def norm(self, base=None):
"""Vector norm.
The norm is the standard Frobenius norm, i.e., the square root of the
sum of the squares of all components with non-angular units.
Parameters
----------
base : instance of ``self.base_representation``
Base relative to which the differentials are defined. This is
required to calculate the physical size of the differential for
all but cartesian differentials.
Returns
-------
norm : `astropy.units.Quantity`
Vector norm, with the same shape as the representation.
"""
return self.to_cartesian(base).norm()
class CartesianDifferential(BaseDifferential):
"""Differentials in of points in 3D cartesian coordinates.
Parameters
----------
d_x, d_y, d_z : `~astropy.units.Quantity` or array
The x, y, and z coordinates of the differentials. If ``d_x``, ``d_y``,
and ``d_z`` have different shapes, they should be broadcastable. If not
quantities, ``unit`` should be set. If only ``d_x`` is given, it is
assumed that it contains an array with the 3 coordinates stored along
``xyz_axis``.
unit : `~astropy.units.Unit` or str
If given, the differentials will be converted to this unit (or taken to
be in this unit if not given.
xyz_axis : int, optional
The axis along which the coordinates are stored when a single array is
provided instead of distinct ``d_x``, ``d_y``, and ``d_z`` (default: 0).
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
base_representation = CartesianRepresentation
def __init__(self, d_x, d_y=None, d_z=None, unit=None, xyz_axis=None,
copy=True):
if d_y is None and d_z is None:
if xyz_axis is not None and xyz_axis != 0:
d_x = np.rollaxis(d_x, xyz_axis, 0)
d_x, d_y, d_z = d_x
elif xyz_axis is not None:
raise ValueError("xyz_axis should only be set if d_x, d_y, and d_z "
"are in a single array passed in through d_x, "
"i.e., d_y and d_z should not be not given.")
elif ((d_y is None and d_z is not None) or
(d_y is not None and d_z is None)):
raise ValueError("d_x, d_y, and d_z are required to instantiate {0}"
.format(self.__class__.__name__))
if unit is not None:
d_x = u.Quantity(d_x, unit, copy=copy, subok=True)
d_y = u.Quantity(d_y, unit, copy=copy, subok=True)
d_z = u.Quantity(d_z, unit, copy=copy, subok=True)
copy = False
super().__init__(d_x, d_y, d_z, copy=copy)
if not (self._d_x.unit.is_equivalent(self._d_y.unit) and
self._d_x.unit.is_equivalent(self._d_z.unit)):
raise u.UnitsError('d_x, d_y and d_z should have equivalent units.')
def to_cartesian(self, base=None):
return CartesianRepresentation(*[getattr(self, c) for c
in self.components])
@classmethod
def from_cartesian(cls, other, base=None):
return cls(*[getattr(other, c) for c in other.components])
def get_d_xyz(self, xyz_axis=0):
"""Return a vector array of the x, y, and z coordinates.
Parameters
----------
xyz_axis : int, optional
The axis in the final array along which the x, y, z components
should be stored (default: 0).
Returns
-------
xyz : `~astropy.units.Quantity`
With dimension 3 along ``xyz_axis``.
"""
return _combine_xyz(self._d_x, self._d_y, self._d_z, xyz_axis=xyz_axis)
d_xyz = property(get_d_xyz)
class BaseSphericalDifferential(BaseDifferential):
def _d_lon_coslat(self, base):
"""Convert longitude differential d_lon to d_lon_coslat.
Parameters
----------
base : instance of ``cls.base_representation``
The base from which the latitude will be taken.
"""
self._check_base(base)
return self.d_lon * np.cos(base.lat)
@classmethod
def _get_d_lon(cls, d_lon_coslat, base):
"""Convert longitude differential d_lon_coslat to d_lon.
Parameters
----------
d_lon_coslat : `~astropy.units.Quantity`
Longitude differential that includes ``cos(lat)``.
base : instance of ``cls.base_representation``
The base from which the latitude will be taken.
"""
cls._check_base(base)
return d_lon_coslat / np.cos(base.lat)
def _combine_operation(self, op, other, reverse=False):
"""Combine two differentials, or a differential with a representation.
If ``other`` is of the same differential type as ``self``, the
components will simply be combined. If both are different parts of
a `~astropy.coordinates.SphericalDifferential` (e.g., a
`~astropy.coordinates.UnitSphericalDifferential` and a
`~astropy.coordinates.RadialDifferential`), they will combined
appropriately.
If ``other`` is a representation, it will be used as a base for which
to evaluate the differential, and the result is a new representation.
Parameters
----------
op : `~operator` callable
Operator to apply (e.g., `~operator.add`, `~operator.sub`, etc.
other : `~astropy.coordinates.BaseRepresentation` instance
The other differential or representation.
reverse : bool
Whether the operands should be reversed (e.g., as we got here via
``self.__rsub__`` because ``self`` is a subclass of ``other``).
"""
if (isinstance(other, BaseSphericalDifferential) and
not isinstance(self, type(other)) or
isinstance(other, RadialDifferential)):
all_components = set(self.components) | set(other.components)
first, second = (self, other) if not reverse else (other, self)
result_args = {c: op(getattr(first, c, 0.), getattr(second, c, 0.))
for c in all_components}
return SphericalDifferential(**result_args)
return super()._combine_operation(op, other, reverse)
class UnitSphericalDifferential(BaseSphericalDifferential):
"""Differential(s) of points on a unit sphere.
Parameters
----------
d_lon, d_lat : `~astropy.units.Quantity`
The longitude and latitude of the differentials.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
base_representation = UnitSphericalRepresentation
@classproperty
def _dimensional_differential(cls):
return SphericalDifferential
def __init__(self, d_lon, d_lat, copy=True):
super().__init__(d_lon, d_lat, copy=copy)
if not self._d_lon.unit.is_equivalent(self._d_lat.unit):
raise u.UnitsError('d_lon and d_lat should have equivalent units.')
def to_cartesian(self, base):
if isinstance(base, SphericalRepresentation):
scale = base.distance
elif isinstance(base, PhysicsSphericalRepresentation):
scale = base.r
else:
return super().to_cartesian(base)
base = base.represent_as(UnitSphericalRepresentation)
return scale * super().to_cartesian(base)
def represent_as(self, other_class, base=None):
# Only have enough information to represent other unit-spherical.
if issubclass(other_class, UnitSphericalCosLatDifferential):
return other_class(self._d_lon_coslat(base), self.d_lat)
return super().represent_as(other_class, base)
@classmethod
def from_representation(cls, representation, base=None):
# All spherical differentials can be done without going to Cartesian,
# though CosLat needs base for the latitude.
if isinstance(representation, SphericalDifferential):
return cls(representation.d_lon, representation.d_lat)
elif isinstance(representation, (SphericalCosLatDifferential,
UnitSphericalCosLatDifferential)):
d_lon = cls._get_d_lon(representation.d_lon_coslat, base)
return cls(d_lon, representation.d_lat)
elif isinstance(representation, PhysicsSphericalDifferential):
return cls(representation.d_phi, -representation.d_theta)
return super().from_representation(representation, base)
class SphericalDifferential(BaseSphericalDifferential):
"""Differential(s) of points in 3D spherical coordinates.
Parameters
----------
d_lon, d_lat : `~astropy.units.Quantity`
The differential longitude and latitude.
d_distance : `~astropy.units.Quantity`
The differential distance.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
base_representation = SphericalRepresentation
_unit_differential = UnitSphericalDifferential
def __init__(self, d_lon, d_lat, d_distance, copy=True):
super().__init__(d_lon, d_lat, d_distance, copy=copy)
if not self._d_lon.unit.is_equivalent(self._d_lat.unit):
raise u.UnitsError('d_lon and d_lat should have equivalent units.')
def represent_as(self, other_class, base=None):
# All spherical differentials can be done without going to Cartesian,
# though CosLat needs base for the latitude.
if issubclass(other_class, UnitSphericalDifferential):
return other_class(self.d_lon, self.d_lat)
elif issubclass(other_class, RadialDifferential):
return other_class(self.d_distance)
elif issubclass(other_class, SphericalCosLatDifferential):
return other_class(self._d_lon_coslat(base), self.d_lat,
self.d_distance)
elif issubclass(other_class, UnitSphericalCosLatDifferential):
return other_class(self._d_lon_coslat(base), self.d_lat)
elif issubclass(other_class, PhysicsSphericalDifferential):
return other_class(self.d_lon, -self.d_lat, self.d_distance)
else:
return super().represent_as(other_class, base)
@classmethod
def from_representation(cls, representation, base=None):
# Other spherical differentials can be done without going to Cartesian,
# though CosLat needs base for the latitude.
if isinstance(representation, SphericalCosLatDifferential):
d_lon = cls._get_d_lon(representation.d_lon_coslat, base)
return cls(d_lon, representation.d_lat, representation.d_distance)
elif isinstance(representation, PhysicsSphericalDifferential):
return cls(representation.d_phi, -representation.d_theta,
representation.d_r)
return super().from_representation(representation, base)
class BaseSphericalCosLatDifferential(BaseDifferential):
"""Differtials from points on a spherical base representation.
With cos(lat) assumed to be included in the longitude differential.
"""
@classmethod
def _get_base_vectors(cls, base):
"""Get unit vectors and scale factors from (unit)spherical base.
Parameters
----------
base : instance of ``self.base_representation``
The points for which the unit vectors and scale factors should be
retrieved.
Returns
-------
unit_vectors : dict of `CartesianRepresentation`
In the directions of the coordinates of base.
scale_factors : dict of `~astropy.units.Quantity`
Scale factors for each of the coordinates. The scale factor for
longitude does not include the cos(lat) factor.
Raises
------
TypeError : if the base is not of the correct type
"""
cls._check_base(base)
return base.unit_vectors(), base.scale_factors(omit_coslat=True)
def _d_lon(self, base):
"""Convert longitude differential with cos(lat) to one without.
Parameters
----------
base : instance of ``cls.base_representation``
The base from which the latitude will be taken.
"""
self._check_base(base)
return self.d_lon_coslat / np.cos(base.lat)
@classmethod
def _get_d_lon_coslat(cls, d_lon, base):
"""Convert longitude differential d_lon to d_lon_coslat.
Parameters
----------
d_lon : `~astropy.units.Quantity`
Value of the longitude differential without ``cos(lat)``.
base : instance of ``cls.base_representation``
The base from which the latitude will be taken.
"""
cls._check_base(base)
return d_lon * np.cos(base.lat)
def _combine_operation(self, op, other, reverse=False):
"""Combine two differentials, or a differential with a representation.
If ``other`` is of the same differential type as ``self``, the
components will simply be combined. If both are different parts of
a `~astropy.coordinates.SphericalDifferential` (e.g., a
`~astropy.coordinates.UnitSphericalDifferential` and a
`~astropy.coordinates.RadialDifferential`), they will combined
appropriately.
If ``other`` is a representation, it will be used as a base for which
to evaluate the differential, and the result is a new representation.
Parameters
----------
op : `~operator` callable
Operator to apply (e.g., `~operator.add`, `~operator.sub`, etc.
other : `~astropy.coordinates.BaseRepresentation` instance
The other differential or representation.
reverse : bool
Whether the operands should be reversed (e.g., as we got here via
``self.__rsub__`` because ``self`` is a subclass of ``other``).
"""
if (isinstance(other, BaseSphericalCosLatDifferential) and
not isinstance(self, type(other)) or
isinstance(other, RadialDifferential)):
all_components = set(self.components) | set(other.components)
first, second = (self, other) if not reverse else (other, self)
result_args = {c: op(getattr(first, c, 0.), getattr(second, c, 0.))
for c in all_components}
return SphericalCosLatDifferential(**result_args)
return super()._combine_operation(op, other, reverse)
class UnitSphericalCosLatDifferential(BaseSphericalCosLatDifferential):
"""Differential(s) of points on a unit sphere.
Parameters
----------
d_lon_coslat, d_lat : `~astropy.units.Quantity`
The longitude and latitude of the differentials.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
base_representation = UnitSphericalRepresentation
attr_classes = OrderedDict([('d_lon_coslat', u.Quantity),
('d_lat', u.Quantity)])
@classproperty
def _dimensional_differential(cls):
return SphericalCosLatDifferential
def __init__(self, d_lon_coslat, d_lat, copy=True):
super().__init__(d_lon_coslat, d_lat, copy=copy)
if not self._d_lon_coslat.unit.is_equivalent(self._d_lat.unit):
raise u.UnitsError('d_lon_coslat and d_lat should have equivalent '
'units.')
def to_cartesian(self, base):
if isinstance(base, SphericalRepresentation):
scale = base.distance
elif isinstance(base, PhysicsSphericalRepresentation):
scale = base.r
else:
return super().to_cartesian(base)
base = base.represent_as(UnitSphericalRepresentation)
return scale * super().to_cartesian(base)
def represent_as(self, other_class, base=None):
# Only have enough information to represent other unit-spherical.
if issubclass(other_class, UnitSphericalDifferential):
return other_class(self._d_lon(base), self.d_lat)
return super().represent_as(other_class, base)
@classmethod
def from_representation(cls, representation, base=None):
# All spherical differentials can be done without going to Cartesian,
# though w/o CosLat needs base for the latitude.
if isinstance(representation, SphericalCosLatDifferential):
return cls(representation.d_lon_coslat, representation.d_lat)
elif isinstance(representation, (SphericalDifferential,
UnitSphericalDifferential)):
d_lon_coslat = cls._get_d_lon_coslat(representation.d_lon, base)
return cls(d_lon_coslat, representation.d_lat)
elif isinstance(representation, PhysicsSphericalDifferential):
d_lon_coslat = cls._get_d_lon_coslat(representation.d_phi, base)
return cls(d_lon_coslat, -representation.d_theta)
return super().from_representation(representation, base)
class SphericalCosLatDifferential(BaseSphericalCosLatDifferential):
"""Differential(s) of points in 3D spherical coordinates.
Parameters
----------
d_lon_coslat, d_lat : `~astropy.units.Quantity`
The differential longitude (with cos(lat) included) and latitude.
d_distance : `~astropy.units.Quantity`
The differential distance.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
base_representation = SphericalRepresentation
_unit_differential = UnitSphericalCosLatDifferential
attr_classes = OrderedDict([('d_lon_coslat', u.Quantity),
('d_lat', u.Quantity),
('d_distance', u.Quantity)])
def __init__(self, d_lon_coslat, d_lat, d_distance, copy=True):
super().__init__(d_lon_coslat, d_lat, d_distance, copy=copy)
if not self._d_lon_coslat.unit.is_equivalent(self._d_lat.unit):
raise u.UnitsError('d_lon_coslat and d_lat should have equivalent '
'units.')
def represent_as(self, other_class, base=None):
# All spherical differentials can be done without going to Cartesian,
# though some need base for the latitude to remove cos(lat).
if issubclass(other_class, UnitSphericalCosLatDifferential):
return other_class(self.d_lon_coslat, self.d_lat)
elif issubclass(other_class, RadialDifferential):
return other_class(self.d_distance)
elif issubclass(other_class, SphericalDifferential):
return other_class(self._d_lon(base), self.d_lat, self.d_distance)
elif issubclass(other_class, UnitSphericalDifferential):
return other_class(self._d_lon(base), self.d_lat)
elif issubclass(other_class, PhysicsSphericalDifferential):
return other_class(self._d_lon(base), -self.d_lat, self.d_distance)
return super().represent_as(other_class, base)
@classmethod
def from_representation(cls, representation, base=None):
# Other spherical differentials can be done without going to Cartesian,
# though we need base for the latitude to remove coslat.
if isinstance(representation, SphericalDifferential):
d_lon_coslat = cls._get_d_lon_coslat(representation.d_lon, base)
return cls(d_lon_coslat, representation.d_lat,
representation.d_distance)
elif isinstance(representation, PhysicsSphericalDifferential):
d_lon_coslat = cls._get_d_lon_coslat(representation.d_phi, base)
return cls(d_lon_coslat, -representation.d_theta,
representation.d_r)
return super().from_representation(representation, base)
class RadialDifferential(BaseDifferential):
"""Differential(s) of radial distances.
Parameters
----------
d_distance : `~astropy.units.Quantity`
The differential distance.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
base_representation = RadialRepresentation
def to_cartesian(self, base):
return self.d_distance * base.represent_as(
UnitSphericalRepresentation).to_cartesian()
@classmethod
def from_cartesian(cls, other, base):
return cls(other.dot(base.represent_as(UnitSphericalRepresentation)),
copy=False)
@classmethod
def from_representation(cls, representation, base=None):
if isinstance(representation, (SphericalDifferential,
SphericalCosLatDifferential)):
return cls(representation.d_distance)
elif isinstance(representation, PhysicsSphericalDifferential):
return cls(representation.d_r)
else:
return super().from_representation(representation, base)
def _combine_operation(self, op, other, reverse=False):
if isinstance(other, self.base_representation):
if reverse:
first, second = other.distance, self.d_distance
else:
first, second = self.d_distance, other.distance
return other.__class__(op(first, second), copy=False)
elif isinstance(other, (BaseSphericalDifferential,
BaseSphericalCosLatDifferential)):
all_components = set(self.components) | set(other.components)
first, second = (self, other) if not reverse else (other, self)
result_args = {c: op(getattr(first, c, 0.), getattr(second, c, 0.))
for c in all_components}
return SphericalDifferential(**result_args)
else:
return super()._combine_operation(op, other, reverse)
class PhysicsSphericalDifferential(BaseDifferential):
"""Differential(s) of 3D spherical coordinates using physics convention.
Parameters
----------
d_phi, d_theta : `~astropy.units.Quantity`
The differential azimuth and inclination.
d_r : `~astropy.units.Quantity`
The differential radial distance.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
base_representation = PhysicsSphericalRepresentation
def __init__(self, d_phi, d_theta, d_r, copy=True):
super().__init__(d_phi, d_theta, d_r, copy=copy)
if not self._d_phi.unit.is_equivalent(self._d_theta.unit):
raise u.UnitsError('d_phi and d_theta should have equivalent '
'units.')
def represent_as(self, other_class, base=None):
# All spherical differentials can be done without going to Cartesian,
# though CosLat needs base for the latitude. For those, explicitly
# do the equivalent of self._d_lon_coslat in SphericalDifferential.
if issubclass(other_class, SphericalDifferential):
return other_class(self.d_phi, -self.d_theta, self.d_r)
elif issubclass(other_class, UnitSphericalDifferential):
return other_class(self.d_phi, -self.d_theta)
elif issubclass(other_class, SphericalCosLatDifferential):
self._check_base(base)
d_lon_coslat = self.d_phi * np.sin(base.theta)
return other_class(d_lon_coslat, -self.d_theta, self.d_r)
elif issubclass(other_class, UnitSphericalCosLatDifferential):
self._check_base(base)
d_lon_coslat = self.d_phi * np.sin(base.theta)
return other_class(d_lon_coslat, -self.d_theta)
elif issubclass(other_class, RadialDifferential):
return other_class(self.d_r)
return super().represent_as(other_class, base)
@classmethod
def from_representation(cls, representation, base=None):
# Other spherical differentials can be done without going to Cartesian,
# though we need base for the latitude to remove coslat. For that case,
# do the equivalent of cls._d_lon in SphericalDifferential.
if isinstance(representation, SphericalDifferential):
return cls(representation.d_lon, -representation.d_lat,
representation.d_distance)
elif isinstance(representation, SphericalCosLatDifferential):
cls._check_base(base)
d_phi = representation.d_lon_coslat / np.sin(base.theta)
return cls(d_phi, -representation.d_lat, representation.d_distance)
return super().from_representation(representation, base)
class CylindricalDifferential(BaseDifferential):
"""Differential(s) of points in cylindrical coordinates.
Parameters
----------
d_rho : `~astropy.units.Quantity`
The differential cylindrical radius.
d_phi : `~astropy.units.Quantity`
The differential azimuth.
d_z : `~astropy.units.Quantity`
The differential height.
copy : bool, optional
If `True` (default), arrays will be copied rather than referenced.
"""
base_representation = CylindricalRepresentation
def __init__(self, d_rho, d_phi, d_z, copy=False):
super().__init__(d_rho, d_phi, d_z, copy=copy)
if not self._d_rho.unit.is_equivalent(self._d_z.unit):
raise u.UnitsError("d_rho and d_z should have equivalent units.")
|
23826b6f9965ffcd5d2e49544acc399d0aa689f430bb4a418a451a1793c4abc2 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module contains convenience functions for getting a coordinate object
for a named object by querying SESAME and getting the first returned result.
Note that this is intended to be a convenience, and is very simple. If you
need precise coordinates for an object you should find the appropriate
reference for that measurement and input the coordinates manually.
"""
# Standard library
import os
import re
import socket
import urllib.request
import urllib.parse
import urllib.error
# Astropy
from .. import units as u
from .sky_coordinate import SkyCoord
from ..utils import data
from ..utils.state import ScienceState
__all__ = ["get_icrs_coordinates"]
class sesame_url(ScienceState):
"""
The URL(s) to Sesame's web-queryable database.
"""
_value = ["http://cdsweb.u-strasbg.fr/cgi-bin/nph-sesame/",
"http://vizier.cfa.harvard.edu/viz-bin/nph-sesame/"]
@classmethod
def validate(cls, value):
# TODO: Implement me
return value
class sesame_database(ScienceState):
"""
This specifies the default database that SESAME will query when
using the name resolve mechanism in the coordinates
subpackage. Default is to search all databases, but this can be
'all', 'simbad', 'ned', or 'vizier'.
"""
_value = 'all'
@classmethod
def validate(cls, value):
if value not in ['all', 'simbad', 'ned', 'vizier']:
raise ValueError("Unknown database '{0}'".format(value))
return value
class NameResolveError(Exception):
pass
def _parse_response(resp_data):
"""
Given a string response from SESAME, parse out the coordinates by looking
for a line starting with a J, meaning ICRS J2000 coordinates.
Parameters
----------
resp_data : str
The string HTTP response from SESAME.
Returns
-------
ra : str
The string Right Ascension parsed from the HTTP response.
dec : str
The string Declination parsed from the HTTP response.
"""
pattr = re.compile(r"%J\s*([0-9\.]+)\s*([\+\-\.0-9]+)")
matched = pattr.search(resp_data.decode('utf-8'))
if matched is None:
return None, None
else:
ra, dec = matched.groups()
return ra, dec
def get_icrs_coordinates(name):
"""
Retrieve an ICRS object by using an online name resolving service to
retrieve coordinates for the specified name. By default, this will
search all available databases until a match is found. If you would like
to specify the database, use the science state
``astropy.coordinates.name_resolve.sesame_database``. You can also
specify a list of servers to use for querying Sesame using the science
state ``astropy.coordinates.name_resolve.sesame_url``. This will try
each one in order until a valid response is returned. By default, this
list includes the main Sesame host and a mirror at vizier. The
configuration item `astropy.utils.data.Conf.remote_timeout` controls the
number of seconds to wait for a response from the server before giving
up.
Parameters
----------
name : str
The name of the object to get coordinates for, e.g. ``'M42'``.
Returns
-------
coord : `astropy.coordinates.ICRS` object
The object's coordinates in the ICRS frame.
"""
database = sesame_database.get()
# The web API just takes the first letter of the database name
db = database.upper()[0]
# Make sure we don't have duplicates in the url list
urls = []
domains = []
for url in sesame_url.get():
domain = urllib.parse.urlparse(url).netloc
# Check for duplicates
if domain not in domains:
domains.append(domain)
# Add the query to the end of the url, add to url list
fmt_url = os.path.join(url, "{db}?{name}")
fmt_url = fmt_url.format(name=urllib.parse.quote(name), db=db)
urls.append(fmt_url)
exceptions = []
for url in urls:
try:
# Retrieve ascii name resolve data from CDS
resp = urllib.request.urlopen(url, timeout=data.conf.remote_timeout)
resp_data = resp.read()
break
except urllib.error.URLError as e:
exceptions.append(e)
continue
except socket.timeout as e:
# There are some cases where urllib2 does not catch socket.timeout
# especially while receiving response data on an already previously
# working request
exceptions.append(e)
continue
# All Sesame URL's failed...
else:
messages = ["{url}: {e.reason}".format(url=url, e=e)
for url, e in zip(urls, exceptions)]
raise NameResolveError("All Sesame queries failed. Unable to "
"retrieve coordinates. See errors per URL "
"below: \n {}".format("\n".join(messages)))
ra, dec = _parse_response(resp_data)
if ra is None and dec is None:
if db == "A":
err = "Unable to find coordinates for name '{0}'".format(name)
else:
err = "Unable to find coordinates for name '{0}' in database {1}"\
.format(name, database)
raise NameResolveError(err)
# Return SkyCoord object
sc = SkyCoord(ra=ra, dec=dec, unit=(u.degree, u.degree), frame='icrs')
return sc
|
445cd520bccd61624a756d53330807513bfbb48cbba0715cb0c2f3bcb8be6172 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
# Note that files generated by lex/yacc not always fully py 2/3 compatible.
# Hence, the ``clean_parse_tables.py`` tool in the astropy-tools
# (https://github.com/astropy/astropy-tools) repository should be used to fix
# this when/if lextab/parsetab files are re-generated.
"""
This module contains utility functions that are for internal use in
astropy.coordinates.angles. Mainly they are conversions from one format
of data to another.
"""
import os
from warnings import warn
import numpy as np
from .errors import (IllegalHourWarning, IllegalHourError,
IllegalMinuteWarning, IllegalMinuteError,
IllegalSecondWarning, IllegalSecondError)
from ..utils import format_exception
from .. import units as u
class _AngleParser:
"""
Parses the various angle formats including:
* 01:02:30.43 degrees
* 1 2 0 hours
* 1°2′3″
* 1d2m3s
* -1h2m3s
This class should not be used directly. Use `parse_angle`
instead.
"""
def __init__(self):
# TODO: in principle, the parser should be invalidated if we change unit
# system (from CDS to FITS, say). Might want to keep a link to the
# unit_registry used, and regenerate the parser/lexer if it changes.
# Alternatively, perhaps one should not worry at all and just pre-
# generate the parser for each release (as done for unit formats).
# For some discussion of this problem, see
# https://github.com/astropy/astropy/issues/5350#issuecomment-248770151
if '_parser' not in _AngleParser.__dict__:
_AngleParser._parser, _AngleParser._lexer = self._make_parser()
@classmethod
def _get_simple_unit_names(cls):
simple_units = set(
u.radian.find_equivalent_units(include_prefix_units=True))
simple_unit_names = set()
# We filter out degree and hourangle, since those are treated
# separately.
for unit in simple_units:
if unit != u.deg and unit != u.hourangle:
simple_unit_names.update(unit.names)
return list(simple_unit_names)
@classmethod
def _make_parser(cls):
from ..extern.ply import lex, yacc
# List of token names.
tokens = (
'SIGN',
'UINT',
'UFLOAT',
'COLON',
'DEGREE',
'HOUR',
'MINUTE',
'SECOND',
'SIMPLE_UNIT'
)
# NOTE THE ORDERING OF THESE RULES IS IMPORTANT!!
# Regular expression rules for simple tokens
def t_UFLOAT(t):
r'((\d+\.\d*)|(\.\d+))([eE][+-−]?\d+)?'
# The above includes Unicode "MINUS SIGN" \u2212. It is
# important to include the hyphen last, or the regex will
# treat this as a range.
t.value = float(t.value.replace('−', '-'))
return t
def t_UINT(t):
r'\d+'
t.value = int(t.value)
return t
def t_SIGN(t):
r'[+−-]'
# The above include Unicode "MINUS SIGN" \u2212. It is
# important to include the hyphen last, or the regex will
# treat this as a range.
if t.value == '+':
t.value = 1.0
else:
t.value = -1.0
return t
def t_SIMPLE_UNIT(t):
t.value = u.Unit(t.value)
return t
t_SIMPLE_UNIT.__doc__ = '|'.join(
'(?:{0})'.format(x) for x in cls._get_simple_unit_names())
t_COLON = ':'
t_DEGREE = r'd(eg(ree(s)?)?)?|°'
t_HOUR = r'hour(s)?|h(r)?|ʰ'
t_MINUTE = r'm(in(ute(s)?)?)?|′|\'|ᵐ'
t_SECOND = r's(ec(ond(s)?)?)?|″|\"|ˢ'
# A string containing ignored characters (spaces)
t_ignore = ' '
# Error handling rule
def t_error(t):
raise ValueError(
"Invalid character at col {0}".format(t.lexpos))
# Build the lexer
lexer = lex.lex(optimize=True, lextab='angle_lextab',
outputdir=os.path.dirname(__file__))
def p_angle(p):
'''
angle : hms
| dms
| arcsecond
| arcminute
| simple
'''
p[0] = p[1]
def p_sign(p):
'''
sign : SIGN
|
'''
if len(p) == 2:
p[0] = p[1]
else:
p[0] = 1.0
def p_ufloat(p):
'''
ufloat : UFLOAT
| UINT
'''
p[0] = float(p[1])
def p_colon(p):
'''
colon : sign UINT COLON ufloat
| sign UINT COLON UINT COLON ufloat
'''
if len(p) == 5:
p[0] = (p[1] * p[2], p[4])
elif len(p) == 7:
p[0] = (p[1] * p[2], p[4], p[6])
def p_spaced(p):
'''
spaced : sign UINT ufloat
| sign UINT UINT ufloat
'''
if len(p) == 4:
p[0] = (p[1] * p[2], p[3])
elif len(p) == 5:
p[0] = (p[1] * p[2], p[3], p[4])
def p_generic(p):
'''
generic : colon
| spaced
| sign UFLOAT
| sign UINT
'''
if len(p) == 2:
p[0] = p[1]
else:
p[0] = p[1] * p[2]
def p_hms(p):
'''
hms : sign UINT HOUR
| sign UINT HOUR ufloat
| sign UINT HOUR UINT MINUTE
| sign UINT HOUR UFLOAT MINUTE
| sign UINT HOUR UINT MINUTE ufloat
| sign UINT HOUR UINT MINUTE ufloat SECOND
| generic HOUR
'''
if len(p) == 3:
p[0] = (p[1], u.hourangle)
elif len(p) == 4:
p[0] = (p[1] * p[2], u.hourangle)
elif len(p) in (5, 6):
p[0] = ((p[1] * p[2], p[4]), u.hourangle)
elif len(p) in (7, 8):
p[0] = ((p[1] * p[2], p[4], p[6]), u.hourangle)
def p_dms(p):
'''
dms : sign UINT DEGREE
| sign UINT DEGREE ufloat
| sign UINT DEGREE UINT MINUTE
| sign UINT DEGREE UFLOAT MINUTE
| sign UINT DEGREE UINT MINUTE ufloat
| sign UINT DEGREE UINT MINUTE ufloat SECOND
| generic DEGREE
'''
if len(p) == 3:
p[0] = (p[1], u.degree)
elif len(p) == 4:
p[0] = (p[1] * p[2], u.degree)
elif len(p) in (5, 6):
p[0] = ((p[1] * p[2], p[4]), u.degree)
elif len(p) in (7, 8):
p[0] = ((p[1] * p[2], p[4], p[6]), u.degree)
def p_simple(p):
'''
simple : generic
| generic SIMPLE_UNIT
'''
if len(p) == 2:
p[0] = (p[1], None)
else:
p[0] = (p[1], p[2])
def p_arcsecond(p):
'''
arcsecond : generic SECOND
'''
p[0] = (p[1], u.arcsecond)
def p_arcminute(p):
'''
arcminute : generic MINUTE
'''
p[0] = (p[1], u.arcminute)
def p_error(p):
raise ValueError
parser = yacc.yacc(debug=False, tabmodule='angle_parsetab',
outputdir=os.path.dirname(__file__),
write_tables=True)
return parser, lexer
def parse(self, angle, unit, debug=False):
try:
found_angle, found_unit = self._parser.parse(
angle, lexer=self._lexer, debug=debug)
except ValueError as e:
if str(e):
raise ValueError("{0} in angle {1!r}".format(
str(e), angle))
else:
raise ValueError(
"Syntax error parsing angle {0!r}".format(angle))
if unit is None and found_unit is None:
raise u.UnitsError("No unit specified")
return found_angle, found_unit
def _check_hour_range(hrs):
"""
Checks that the given value is in the range (-24, 24).
"""
if np.any(np.abs(hrs) == 24.):
warn(IllegalHourWarning(hrs, 'Treating as 24 hr'))
elif np.any(hrs < -24.) or np.any(hrs > 24.):
raise IllegalHourError(hrs)
def _check_minute_range(m):
"""
Checks that the given value is in the range [0,60]. If the value
is equal to 60, then a warning is raised.
"""
if np.any(m == 60.):
warn(IllegalMinuteWarning(m, 'Treating as 0 min, +1 hr/deg'))
elif np.any(m < -60.) or np.any(m > 60.):
# "Error: minutes not in range [-60,60) ({0}).".format(min))
raise IllegalMinuteError(m)
def _check_second_range(sec):
"""
Checks that the given value is in the range [0,60]. If the value
is equal to 60, then a warning is raised.
"""
if np.any(sec == 60.):
warn(IllegalSecondWarning(sec, 'Treating as 0 sec, +1 min'))
elif sec is None:
pass
elif np.any(sec < -60.) or np.any(sec > 60.):
# "Error: seconds not in range [-60,60) ({0}).".format(sec))
raise IllegalSecondError(sec)
def check_hms_ranges(h, m, s):
"""
Checks that the given hour, minute and second are all within
reasonable range.
"""
_check_hour_range(h)
_check_minute_range(m)
_check_second_range(s)
return None
def parse_angle(angle, unit=None, debug=False):
"""
Parses an input string value into an angle value.
Parameters
----------
angle : str
A string representing the angle. May be in one of the following forms:
* 01:02:30.43 degrees
* 1 2 0 hours
* 1°2′3″
* 1d2m3s
* -1h2m3s
unit : `~astropy.units.UnitBase` instance, optional
The unit used to interpret the string. If ``unit`` is not
provided, the unit must be explicitly represented in the
string, either at the end or as number separators.
debug : bool, optional
If `True`, print debugging information from the parser.
Returns
-------
value, unit : tuple
``value`` is the value as a floating point number or three-part
tuple, and ``unit`` is a `Unit` instance which is either the
unit passed in or the one explicitly mentioned in the input
string.
"""
return _AngleParser().parse(angle, unit, debug=debug)
def degrees_to_dms(d):
"""
Convert a floating-point degree value into a ``(degree, arcminute,
arcsecond)`` tuple.
"""
sign = np.copysign(1.0, d)
(df, d) = np.modf(np.abs(d)) # (degree fraction, degree)
(mf, m) = np.modf(df * 60.) # (minute fraction, minute)
s = mf * 60.
return np.floor(sign * d), sign * np.floor(m), sign * s
def dms_to_degrees(d, m, s=None):
"""
Convert degrees, arcminute, arcsecond to a float degrees value.
"""
_check_minute_range(m)
_check_second_range(s)
# determine sign
sign = np.copysign(1.0, d)
try:
d = np.floor(np.abs(d))
if s is None:
m = np.abs(m)
s = 0
else:
m = np.floor(np.abs(m))
s = np.abs(s)
except ValueError:
raise ValueError(format_exception(
"{func}: dms values ({1[0]},{2[1]},{3[2]}) could not be "
"converted to numbers.", d, m, s))
return sign * (d + m / 60. + s / 3600.)
def hms_to_hours(h, m, s=None):
"""
Convert hour, minute, second to a float hour value.
"""
check_hms_ranges(h, m, s)
# determine sign
sign = np.copysign(1.0, h)
try:
h = np.floor(np.abs(h))
if s is None:
m = np.abs(m)
s = 0
else:
m = np.floor(np.abs(m))
s = np.abs(s)
except ValueError:
raise ValueError(format_exception(
"{func}: HMS values ({1[0]},{2[1]},{3[2]}) could not be "
"converted to numbers.", h, m, s))
return sign * (h + m / 60. + s / 3600.)
def hms_to_degrees(h, m, s):
"""
Convert hour, minute, second to a float degrees value.
"""
return hms_to_hours(h, m, s) * 15.
def hms_to_radians(h, m, s):
"""
Convert hour, minute, second to a float radians value.
"""
return u.degree.to(u.radian, hms_to_degrees(h, m, s))
def hms_to_dms(h, m, s):
"""
Convert degrees, arcminutes, arcseconds to an ``(hour, minute, second)``
tuple.
"""
return degrees_to_dms(hms_to_degrees(h, m, s))
def hours_to_decimal(h):
"""
Convert any parseable hour value into a float value.
"""
from . import angles
return angles.Angle(h, unit=u.hourangle).hour
def hours_to_radians(h):
"""
Convert an angle in Hours to Radians.
"""
return u.hourangle.to(u.radian, h)
def hours_to_hms(h):
"""
Convert an floating-point hour value into an ``(hour, minute,
second)`` tuple.
"""
sign = np.copysign(1.0, h)
(hf, h) = np.modf(np.abs(h)) # (degree fraction, degree)
(mf, m) = np.modf(hf * 60.0) # (minute fraction, minute)
s = mf * 60.0
return (np.floor(sign * h), sign * np.floor(m), sign * s)
def radians_to_degrees(r):
"""
Convert an angle in Radians to Degrees.
"""
return u.radian.to(u.degree, r)
def radians_to_hours(r):
"""
Convert an angle in Radians to Hours.
"""
return u.radian.to(u.hourangle, r)
def radians_to_hms(r):
"""
Convert an angle in Radians to an ``(hour, minute, second)`` tuple.
"""
hours = radians_to_hours(r)
return hours_to_hms(hours)
def radians_to_dms(r):
"""
Convert an angle in Radians to an ``(degree, arcminute,
arcsecond)`` tuple.
"""
degrees = u.radian.to(u.degree, r)
return degrees_to_dms(degrees)
def sexagesimal_to_string(values, precision=None, pad=False, sep=(':',),
fields=3):
"""
Given an already separated tuple of sexagesimal values, returns
a string.
See `hours_to_string` and `degrees_to_string` for a higher-level
interface to this functionality.
"""
# Check to see if values[0] is negative, using np.copysign to handle -0
sign = np.copysign(1.0, values[0])
# If the coordinates are negative, we need to take the absolute values.
# We use np.abs because abs(-0) is -0
# TODO: Is this true? (MHvK, 2018-02-01: not on my system)
values = [np.abs(value) for value in values]
if pad:
if sign == -1:
pad = 3
else:
pad = 2
else:
pad = 0
if not isinstance(sep, tuple):
sep = tuple(sep)
if fields < 1 or fields > 3:
raise ValueError(
"fields must be 1, 2, or 3")
if not sep: # empty string, False, or None, etc.
sep = ('', '', '')
elif len(sep) == 1:
if fields == 3:
sep = sep + (sep[0], '')
elif fields == 2:
sep = sep + ('', '')
else:
sep = ('', '', '')
elif len(sep) == 2:
sep = sep + ('',)
elif len(sep) != 3:
raise ValueError(
"Invalid separator specification for converting angle to string.")
# Simplify the expression based on the requested precision. For
# example, if the seconds will round up to 60, we should convert
# it to 0 and carry upwards. If the field is hidden (by the
# fields kwarg) we round up around the middle, 30.0.
if precision is None:
rounding_thresh = 60.0 - (10.0 ** -4)
else:
rounding_thresh = 60.0 - (10.0 ** -precision)
if fields == 3 and values[2] >= rounding_thresh:
values[2] = 0.0
values[1] += 1.0
elif fields < 3 and values[2] >= 30.0:
values[1] += 1.0
if fields >= 2 and values[1] >= 60.0:
values[1] = 0.0
values[0] += 1.0
elif fields < 2 and values[1] >= 30.0:
values[0] += 1.0
literal = []
last_value = ''
literal.append('{0:0{pad}.0f}{sep[0]}')
if fields >= 2:
literal.append('{1:02d}{sep[1]}')
if fields == 3:
if precision is None:
last_value = '{0:.4f}'.format(abs(values[2]))
last_value = last_value.rstrip('0').rstrip('.')
else:
last_value = '{0:.{precision}f}'.format(
abs(values[2]), precision=precision)
if len(last_value) == 1 or last_value[1] == '.':
last_value = '0' + last_value
literal.append('{last_value}{sep[2]}')
literal = ''.join(literal)
return literal.format(np.copysign(values[0], sign),
int(values[1]), values[2],
sep=sep, pad=pad,
last_value=last_value)
def hours_to_string(h, precision=5, pad=False, sep=('h', 'm', 's'),
fields=3):
"""
Takes a decimal hour value and returns a string formatted as hms with
separator specified by the 'sep' parameter.
``h`` must be a scalar.
"""
h, m, s = hours_to_hms(h)
return sexagesimal_to_string((h, m, s), precision=precision, pad=pad,
sep=sep, fields=fields)
def degrees_to_string(d, precision=5, pad=False, sep=':', fields=3):
"""
Takes a decimal hour value and returns a string formatted as dms with
separator specified by the 'sep' parameter.
``d`` must be a scalar.
"""
d, m, s = degrees_to_dms(d)
return sexagesimal_to_string((d, m, s), precision=precision, pad=pad,
sep=sep, fields=fields)
def angular_separation(lon1, lat1, lon2, lat2):
"""
Angular separation between two points on a sphere.
Parameters
----------
lon1, lat1, lon2, lat2 : `Angle`, `~astropy.units.Quantity` or float
Longitude and latitude of the two points. Quantities should be in
angular units; floats in radians.
Returns
-------
angular separation : `~astropy.units.Quantity` or float
Type depends on input; `Quantity` in angular units, or float in
radians.
Notes
-----
The angular separation is calculated using the Vincenty formula [1]_,
which is slightly more complex and computationally expensive than
some alternatives, but is stable at at all distances, including the
poles and antipodes.
.. [1] https://en.wikipedia.org/wiki/Great-circle_distance
"""
sdlon = np.sin(lon2 - lon1)
cdlon = np.cos(lon2 - lon1)
slat1 = np.sin(lat1)
slat2 = np.sin(lat2)
clat1 = np.cos(lat1)
clat2 = np.cos(lat2)
num1 = clat2 * sdlon
num2 = clat1 * slat2 - slat1 * clat2 * cdlon
denominator = slat1 * slat2 + clat1 * clat2 * cdlon
return np.arctan2(np.hypot(num1, num2), denominator)
def position_angle(lon1, lat1, lon2, lat2):
"""
Position Angle (East of North) between two points on a sphere.
Parameters
----------
lon1, lat1, lon2, lat2 : `Angle`, `~astropy.units.Quantity` or float
Longitude and latitude of the two points. Quantities should be in
angular units; floats in radians.
Returns
-------
pa : `~astropy.coordinates.Angle`
The (positive) position angle of the vector pointing from position 1 to
position 2. If any of the angles are arrays, this will contain an array
following the appropriate `numpy` broadcasting rules.
"""
from .angles import Angle
deltalon = lon2 - lon1
colat = np.cos(lat2)
x = np.sin(lat2) * np.cos(lat1) - colat * np.sin(lat1) * np.cos(deltalon)
y = np.sin(deltalon) * colat
return Angle(np.arctan2(y, x), u.radian).wrap_at(360*u.deg)
|
d7d904bfe5c982549f608d285422f0f7e71cff82a36979dca6980bea9e5def1c | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module contains a general framework for defining graphs of transformations
between coordinates, suitable for either spatial coordinates or more generalized
coordinate systems.
The fundamental idea is that each class is a node in the transformation graph,
and transitions from one node to another are defined as functions (or methods)
wrapped in transformation objects.
This module also includes more specific transformation classes for
celestial/spatial coordinate frames, generally focused around matrix-style
transformations that are typically how the algorithms are defined.
"""
import heapq
import inspect
import subprocess
from warnings import warn
from abc import ABCMeta, abstractmethod
from collections import defaultdict, OrderedDict
from contextlib import suppress
from inspect import signature
import numpy as np
from .. import units as u
from ..utils.exceptions import AstropyWarning
from .representation import REPRESENTATION_CLASSES
__all__ = ['TransformGraph', 'CoordinateTransform', 'FunctionTransform',
'BaseAffineTransform', 'AffineTransform',
'StaticMatrixTransform', 'DynamicMatrixTransform',
'FunctionTransformWithFiniteDifference', 'CompositeTransform']
def frame_attrs_from_set(frame_set):
"""
A `dict` of all the attributes of all frame classes in this
`TransformGraph`.
Broken out of the class so this can be called on a temporary frame set to
validate new additions to the transform graph before actually adding them.
"""
result = {}
for frame_cls in frame_set:
result.update(frame_cls.frame_attributes)
return result
def frame_comps_from_set(frame_set):
"""
A `set` of all component names every defined within any frame class in
this `TransformGraph`.
Broken out of the class so this can be called on a temporary frame set to
validate new additions to the transform graph before actually adding them.
"""
result = set()
for frame_cls in frame_set:
rep_info = frame_cls._frame_specific_representation_info
for mappings in rep_info.values():
for rep_map in mappings:
result.update([rep_map.framename])
return result
class TransformGraph:
"""
A graph representing the paths between coordinate frames.
"""
def __init__(self):
self._graph = defaultdict(dict)
self.invalidate_cache() # generates cache entries
@property
def _cached_names(self):
if self._cached_names_dct is None:
self._cached_names_dct = dct = {}
for c in self.frame_set:
nm = getattr(c, 'name', None)
if nm is not None:
dct[nm] = c
return self._cached_names_dct
@property
def frame_set(self):
"""
A `set` of all the frame classes present in this `TransformGraph`.
"""
if self._cached_frame_set is None:
self._cached_frame_set = set()
for a in self._graph:
self._cached_frame_set.add(a)
for b in self._graph[a]:
self._cached_frame_set.add(b)
return self._cached_frame_set.copy()
@property
def frame_attributes(self):
"""
A `dict` of all the attributes of all frame classes in this
`TransformGraph`.
"""
if self._cached_frame_attributes is None:
self._cached_frame_attributes = frame_attrs_from_set(self.frame_set)
return self._cached_frame_attributes
@property
def frame_component_names(self):
"""
A `set` of all component names every defined within any frame class in
this `TransformGraph`.
"""
if self._cached_component_names is None:
self._cached_component_names = frame_comps_from_set(self.frame_set)
return self._cached_component_names
def invalidate_cache(self):
"""
Invalidates the cache that stores optimizations for traversing the
transform graph. This is called automatically when transforms
are added or removed, but will need to be called manually if
weights on transforms are modified inplace.
"""
self._cached_names_dct = None
self._cached_frame_set = None
self._cached_frame_attributes = None
self._cached_component_names = None
self._shortestpaths = {}
self._composite_cache = {}
def add_transform(self, fromsys, tosys, transform):
"""
Add a new coordinate transformation to the graph.
Parameters
----------
fromsys : class
The coordinate frame class to start from.
tosys : class
The coordinate frame class to transform into.
transform : CoordinateTransform or similar callable
The transformation object. Typically a `CoordinateTransform` object,
although it may be some other callable that is called with the same
signature.
Raises
------
TypeError
If ``fromsys`` or ``tosys`` are not classes or ``transform`` is
not callable.
"""
if not inspect.isclass(fromsys):
raise TypeError('fromsys must be a class')
if not inspect.isclass(tosys):
raise TypeError('tosys must be a class')
if not callable(transform):
raise TypeError('transform must be callable')
frame_set = self.frame_set.copy()
frame_set.add(fromsys)
frame_set.add(tosys)
# Now we check to see if any attributes on the proposed frames override
# *any* component names, which we can't allow for some of the logic in
# the SkyCoord initializer to work
attrs = set(frame_attrs_from_set(frame_set).keys())
comps = frame_comps_from_set(frame_set)
invalid_attrs = attrs.intersection(comps)
if invalid_attrs:
invalid_frames = set()
for attr in invalid_attrs:
if attr in fromsys.frame_attributes:
invalid_frames.update([fromsys])
if attr in tosys.frame_attributes:
invalid_frames.update([tosys])
raise ValueError("Frame(s) {0} contain invalid attribute names: {1}"
"\nFrame attributes can not conflict with *any* of"
" the frame data component names (see"
" `frame_transform_graph.frame_component_names`)."
.format(list(invalid_frames), invalid_attrs))
self._graph[fromsys][tosys] = transform
self.invalidate_cache()
def remove_transform(self, fromsys, tosys, transform):
"""
Removes a coordinate transform from the graph.
Parameters
----------
fromsys : class or `None`
The coordinate frame *class* to start from. If `None`,
``transform`` will be searched for and removed (``tosys`` must
also be `None`).
tosys : class or `None`
The coordinate frame *class* to transform into. If `None`,
``transform`` will be searched for and removed (``fromsys`` must
also be `None`).
transform : callable or `None`
The transformation object to be removed or `None`. If `None`
and ``tosys`` and ``fromsys`` are supplied, there will be no
check to ensure the correct object is removed.
"""
if fromsys is None or tosys is None:
if not (tosys is None and fromsys is None):
raise ValueError('fromsys and tosys must both be None if either are')
if transform is None:
raise ValueError('cannot give all Nones to remove_transform')
# search for the requested transform by brute force and remove it
for a in self._graph:
agraph = self._graph[a]
for b in agraph:
if b is transform:
del agraph[b]
break
else:
raise ValueError('Could not find transform {0} in the '
'graph'.format(transform))
else:
if transform is None:
self._graph[fromsys].pop(tosys, None)
else:
curr = self._graph[fromsys].get(tosys, None)
if curr is transform:
self._graph[fromsys].pop(tosys)
else:
raise ValueError('Current transform from {0} to {1} is not '
'{2}'.format(fromsys, tosys, transform))
self.invalidate_cache()
def find_shortest_path(self, fromsys, tosys):
"""
Computes the shortest distance along the transform graph from
one system to another.
Parameters
----------
fromsys : class
The coordinate frame class to start from.
tosys : class
The coordinate frame class to transform into.
Returns
-------
path : list of classes or `None`
The path from ``fromsys`` to ``tosys`` as an in-order sequence
of classes. This list includes *both* ``fromsys`` and
``tosys``. Is `None` if there is no possible path.
distance : number
The total distance/priority from ``fromsys`` to ``tosys``. If
priorities are not set this is the number of transforms
needed. Is ``inf`` if there is no possible path.
"""
inf = float('inf')
# special-case the 0 or 1-path
if tosys is fromsys:
if tosys not in self._graph[fromsys]:
# Means there's no transform necessary to go from it to itself.
return [tosys], 0
if tosys in self._graph[fromsys]:
# this will also catch the case where tosys is fromsys, but has
# a defined transform.
t = self._graph[fromsys][tosys]
return [fromsys, tosys], float(t.priority if hasattr(t, 'priority') else 1)
# otherwise, need to construct the path:
if fromsys in self._shortestpaths:
# already have a cached result
fpaths = self._shortestpaths[fromsys]
if tosys in fpaths:
return fpaths[tosys]
else:
return None, inf
# use Dijkstra's algorithm to find shortest path in all other cases
nodes = []
# first make the list of nodes
for a in self._graph:
if a not in nodes:
nodes.append(a)
for b in self._graph[a]:
if b not in nodes:
nodes.append(b)
if fromsys not in nodes or tosys not in nodes:
# fromsys or tosys are isolated or not registered, so there's
# certainly no way to get from one to the other
return None, inf
edgeweights = {}
# construct another graph that is a dict of dicts of priorities
# (used as edge weights in Dijkstra's algorithm)
for a in self._graph:
edgeweights[a] = aew = {}
agraph = self._graph[a]
for b in agraph:
aew[b] = float(agraph[b].priority if hasattr(agraph[b], 'priority') else 1)
# entries in q are [distance, count, nodeobj, pathlist]
# count is needed because in py 3.x, tie-breaking fails on the nodes.
# this way, insertion order is preserved if the weights are the same
q = [[inf, i, n, []] for i, n in enumerate(nodes) if n is not fromsys]
q.insert(0, [0, -1, fromsys, []])
# this dict will store the distance to node from ``fromsys`` and the path
result = {}
# definitely starts as a valid heap because of the insert line; from the
# node to itself is always the shortest distance
while len(q) > 0:
d, orderi, n, path = heapq.heappop(q)
if d == inf:
# everything left is unreachable from fromsys, just copy them to
# the results and jump out of the loop
result[n] = (None, d)
for d, orderi, n, path in q:
result[n] = (None, d)
break
else:
result[n] = (path, d)
path.append(n)
if n not in edgeweights:
# this is a system that can be transformed to, but not from.
continue
for n2 in edgeweights[n]:
if n2 not in result: # already visited
# find where n2 is in the heap
for i in range(len(q)):
if q[i][2] == n2:
break
else:
raise ValueError('n2 not in heap - this should be impossible!')
newd = d + edgeweights[n][n2]
if newd < q[i][0]:
q[i][0] = newd
q[i][3] = list(path)
heapq.heapify(q)
# cache for later use
self._shortestpaths[fromsys] = result
return result[tosys]
def get_transform(self, fromsys, tosys):
"""
Generates and returns the `CompositeTransform` for a transformation
between two coordinate systems.
Parameters
----------
fromsys : class
The coordinate frame class to start from.
tosys : class
The coordinate frame class to transform into.
Returns
-------
trans : `CompositeTransform` or `None`
If there is a path from ``fromsys`` to ``tosys``, this is a
transform object for that path. If no path could be found, this is
`None`.
Notes
-----
This function always returns a `CompositeTransform`, because
`CompositeTransform` is slightly more adaptable in the way it can be
called than other transform classes. Specifically, it takes care of
intermediate steps of transformations in a way that is consistent with
1-hop transformations.
"""
if not inspect.isclass(fromsys):
raise TypeError('fromsys is not a class')
if not inspect.isclass(tosys):
raise TypeError('tosys is not a class')
path, distance = self.find_shortest_path(fromsys, tosys)
if path is None:
return None
transforms = []
currsys = fromsys
for p in path[1:]: # first element is fromsys so we skip it
transforms.append(self._graph[currsys][p])
currsys = p
fttuple = (fromsys, tosys)
if fttuple not in self._composite_cache:
comptrans = CompositeTransform(transforms, fromsys, tosys,
register_graph=False)
self._composite_cache[fttuple] = comptrans
return self._composite_cache[fttuple]
def lookup_name(self, name):
"""
Tries to locate the coordinate class with the provided alias.
Parameters
----------
name : str
The alias to look up.
Returns
-------
coordcls
The coordinate class corresponding to the ``name`` or `None` if
no such class exists.
"""
return self._cached_names.get(name, None)
def get_names(self):
"""
Returns all available transform names. They will all be
valid arguments to `lookup_name`.
Returns
-------
nms : list
The aliases for coordinate systems.
"""
return list(self._cached_names.keys())
def to_dot_graph(self, priorities=True, addnodes=[], savefn=None,
savelayout='plain', saveformat=None, color_edges=True):
"""
Converts this transform graph to the graphviz_ DOT format.
Optionally saves it (requires `graphviz`_ be installed and on your path).
.. _graphviz: http://www.graphviz.org/
Parameters
----------
priorities : bool
If `True`, show the priority values for each transform. Otherwise,
the will not be included in the graph.
addnodes : sequence of str
Additional coordinate systems to add (this can include systems
already in the transform graph, but they will only appear once).
savefn : `None` or str
The file name to save this graph to or `None` to not save
to a file.
savelayout : str
The graphviz program to use to layout the graph (see
graphviz_ for details) or 'plain' to just save the DOT graph
content. Ignored if ``savefn`` is `None`.
saveformat : str
The graphviz output format. (e.g. the ``-Txxx`` option for
the command line program - see graphviz docs for details).
Ignored if ``savefn`` is `None`.
color_edges : bool
Color the edges between two nodes (frames) based on the type of
transform. ``FunctionTransform``: red, ``StaticMatrixTransform``:
blue, ``DynamicMatrixTransform``: green.
Returns
-------
dotgraph : str
A string with the DOT format graph.
"""
nodes = []
# find the node names
for a in self._graph:
if a not in nodes:
nodes.append(a)
for b in self._graph[a]:
if b not in nodes:
nodes.append(b)
for node in addnodes:
if node not in nodes:
nodes.append(node)
nodenames = []
invclsaliases = dict([(v, k) for k, v in self._cached_names.items()])
for n in nodes:
if n in invclsaliases:
nodenames.append('{0} [shape=oval label="{0}\\n`{1}`"]'.format(n.__name__, invclsaliases[n]))
else:
nodenames.append(n.__name__ + '[ shape=oval ]')
edgenames = []
# Now the edges
for a in self._graph:
agraph = self._graph[a]
for b in agraph:
transform = agraph[b]
pri = transform.priority if hasattr(transform, 'priority') else 1
color = trans_to_color[transform.__class__] if color_edges else 'black'
edgenames.append((a.__name__, b.__name__, pri, color))
# generate simple dot format graph
lines = ['digraph AstropyCoordinateTransformGraph {']
lines.append('; '.join(nodenames) + ';')
for enm1, enm2, weights, color in edgenames:
labelstr_fmt = '[ {0} {1} ]'
if priorities:
priority_part = 'label = "{0}"'.format(weights)
else:
priority_part = ''
color_part = 'color = "{0}"'.format(color)
labelstr = labelstr_fmt.format(priority_part, color_part)
lines.append('{0} -> {1}{2};'.format(enm1, enm2, labelstr))
lines.append('')
lines.append('overlap=false')
lines.append('}')
dotgraph = '\n'.join(lines)
if savefn is not None:
if savelayout == 'plain':
with open(savefn, 'w') as f:
f.write(dotgraph)
else:
args = [savelayout]
if saveformat is not None:
args.append('-T' + saveformat)
proc = subprocess.Popen(args, stdin=subprocess.PIPE,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
stdout, stderr = proc.communicate(dotgraph)
if proc.returncode != 0:
raise OSError('problem running graphviz: \n' + stderr)
with open(savefn, 'w') as f:
f.write(stdout)
return dotgraph
def to_networkx_graph(self):
"""
Converts this transform graph into a networkx graph.
.. note::
You must have the `networkx <http://networkx.lanl.gov/>`_
package installed for this to work.
Returns
-------
nxgraph : `networkx.Graph <http://networkx.lanl.gov/reference/classes.graph.html>`_
This `TransformGraph` as a `networkx.Graph`_.
"""
import networkx as nx
nxgraph = nx.Graph()
# first make the nodes
for a in self._graph:
if a not in nxgraph:
nxgraph.add_node(a)
for b in self._graph[a]:
if b not in nxgraph:
nxgraph.add_node(b)
# Now the edges
for a in self._graph:
agraph = self._graph[a]
for b in agraph:
transform = agraph[b]
pri = transform.priority if hasattr(transform, 'priority') else 1
color = trans_to_color[transform.__class__]
nxgraph.add_edge(a, b, weight=pri, color=color)
return nxgraph
def transform(self, transcls, fromsys, tosys, priority=1, **kwargs):
"""
A function decorator for defining transformations.
.. note::
If decorating a static method of a class, ``@staticmethod``
should be added *above* this decorator.
Parameters
----------
transcls : class
The class of the transformation object to create.
fromsys : class
The coordinate frame class to start from.
tosys : class
The coordinate frame class to transform into.
priority : number
The priority if this transform when finding the shortest
coordinate transform path - large numbers are lower priorities.
Additional keyword arguments are passed into the ``transcls``
constructor.
Returns
-------
deco : function
A function that can be called on another function as a decorator
(see example).
Notes
-----
This decorator assumes the first argument of the ``transcls``
initializer accepts a callable, and that the second and third
are ``fromsys`` and ``tosys``. If this is not true, you should just
initialize the class manually and use `add_transform` instead of
using this decorator.
Examples
--------
::
graph = TransformGraph()
class Frame1(BaseCoordinateFrame):
...
class Frame2(BaseCoordinateFrame):
...
@graph.transform(FunctionTransform, Frame1, Frame2)
def f1_to_f2(f1_obj):
... do something with f1_obj ...
return f2_obj
"""
def deco(func):
# this doesn't do anything directly with the transform because
# ``register_graph=self`` stores it in the transform graph
# automatically
transcls(func, fromsys, tosys, priority=priority,
register_graph=self, **kwargs)
return func
return deco
# <-------------------Define the builtin transform classes-------------------->
class CoordinateTransform(metaclass=ABCMeta):
"""
An object that transforms a coordinate from one system to another.
Subclasses must implement `__call__` with the provided signature.
They should also call this superclass's ``__init__`` in their
``__init__``.
Parameters
----------
fromsys : class
The coordinate frame class to start from.
tosys : class
The coordinate frame class to transform into.
priority : number
The priority if this transform when finding the shortest
coordinate transform path - large numbers are lower priorities.
register_graph : `TransformGraph` or `None`
A graph to register this transformation with on creation, or
`None` to leave it unregistered.
"""
def __init__(self, fromsys, tosys, priority=1, register_graph=None):
if not inspect.isclass(fromsys):
raise TypeError('fromsys must be a class')
if not inspect.isclass(tosys):
raise TypeError('tosys must be a class')
self.fromsys = fromsys
self.tosys = tosys
self.priority = float(priority)
if register_graph:
# this will do the type-checking when it adds to the graph
self.register(register_graph)
else:
if not inspect.isclass(fromsys) or not inspect.isclass(tosys):
raise TypeError('fromsys and tosys must be classes')
self.overlapping_frame_attr_names = overlap = []
if (hasattr(fromsys, 'get_frame_attr_names') and
hasattr(tosys, 'get_frame_attr_names')):
# the if statement is there so that non-frame things might be usable
# if it makes sense
for from_nm in fromsys.get_frame_attr_names():
if from_nm in tosys.get_frame_attr_names():
overlap.append(from_nm)
def register(self, graph):
"""
Add this transformation to the requested Transformation graph,
replacing anything already connecting these two coordinates.
Parameters
----------
graph : a TransformGraph object
The graph to register this transformation with.
"""
graph.add_transform(self.fromsys, self.tosys, self)
def unregister(self, graph):
"""
Remove this transformation from the requested transformation
graph.
Parameters
----------
graph : a TransformGraph object
The graph to unregister this transformation from.
Raises
------
ValueError
If this is not currently in the transform graph.
"""
graph.remove_transform(self.fromsys, self.tosys, self)
@abstractmethod
def __call__(self, fromcoord, toframe):
"""
Does the actual coordinate transformation from the ``fromsys`` class to
the ``tosys`` class.
Parameters
----------
fromcoord : fromsys object
An object of class matching ``fromsys`` that is to be transformed.
toframe : object
An object that has the attributes necessary to fully specify the
frame. That is, it must have attributes with names that match the
keys of the dictionary that ``tosys.get_frame_attr_names()``
returns. Typically this is of class ``tosys``, but it *might* be
some other class as long as it has the appropriate attributes.
Returns
-------
tocoord : tosys object
The new coordinate after the transform has been applied.
"""
class FunctionTransform(CoordinateTransform):
"""
A coordinate transformation defined by a function that accepts a
coordinate object and returns the transformed coordinate object.
Parameters
----------
func : callable
The transformation function. Should have a call signature
``func(formcoord, toframe)``. Note that, unlike
`CoordinateTransform.__call__`, ``toframe`` is assumed to be of type
``tosys`` for this function.
fromsys : class
The coordinate frame class to start from.
tosys : class
The coordinate frame class to transform into.
priority : number
The priority if this transform when finding the shortest
coordinate transform path - large numbers are lower priorities.
register_graph : `TransformGraph` or `None`
A graph to register this transformation with on creation, or
`None` to leave it unregistered.
Raises
------
TypeError
If ``func`` is not callable.
ValueError
If ``func`` cannot accept two arguments.
"""
def __init__(self, func, fromsys, tosys, priority=1, register_graph=None):
if not callable(func):
raise TypeError('func must be callable')
with suppress(TypeError):
sig = signature(func)
kinds = [x.kind for x in sig.parameters.values()]
if (len(x for x in kinds if x == sig.POSITIONAL_ONLY) != 2
and sig.VAR_POSITIONAL not in kinds):
raise ValueError('provided function does not accept two arguments')
self.func = func
super().__init__(fromsys, tosys, priority=priority,
register_graph=register_graph)
def __call__(self, fromcoord, toframe):
res = self.func(fromcoord, toframe)
if not isinstance(res, self.tosys):
raise TypeError('the transformation function yielded {0} but '
'should have been of type {1}'.format(res, self.tosys))
if fromcoord.data.differentials and not res.data.differentials:
warn("Applied a FunctionTransform to a coordinate frame with "
"differentials, but the FunctionTransform does not handle "
"differentials, so they have been dropped.", AstropyWarning)
return res
class FunctionTransformWithFiniteDifference(FunctionTransform):
r"""
A coordinate transformation that works like a `FunctionTransform`, but
computes velocity shifts based on the finite-difference relative to one of
the frame attributes. Note that the transform function should *not* change
the differential at all in this case, as any differentials will be
overridden.
When a differential is in the from coordinate, the finite difference
calculation has two components. The first part is simple the existing
differential, but re-orientation (using finite-difference techniques) to
point in the direction the velocity vector has in the *new* frame. The
second component is the "induced" velocity. That is, the velocity
intrinsic to the frame itself, estimated by shifting the frame using the
``finite_difference_frameattr_name`` frame attribute a small amount
(``finite_difference_dt``) in time and re-calculating the position.
Parameters
----------
finite_difference_frameattr_name : str or None
The name of the frame attribute on the frames to use for the finite
difference. Both the to and the from frame will be checked for this
attribute, but only one needs to have it. If None, no velocity
component induced from the frame itself will be included - only the
re-orientation of any exsiting differential.
finite_difference_dt : `~astropy.units.Quantity` or callable
If a quantity, this is the size of the differential used to do the
finite difference. If a callable, should accept
``(fromcoord, toframe)`` and return the ``dt`` value.
symmetric_finite_difference : bool
If True, the finite difference is computed as
:math:`\frac{x(t + \Delta t / 2) - x(t + \Delta t / 2)}{\Delta t}`, or
if False, :math:`\frac{x(t + \Delta t) - x(t)}{\Delta t}`. The latter
case has slightly better performance (and more stable finite difference
behavior).
All other parameters are identical to the initializer for
`FunctionTransform`.
"""
def __init__(self, func, fromsys, tosys, priority=1, register_graph=None,
finite_difference_frameattr_name='obstime',
finite_difference_dt=1*u.second,
symmetric_finite_difference=True):
super().__init__(func, fromsys, tosys, priority, register_graph)
self.finite_difference_frameattr_name = finite_difference_frameattr_name
self.finite_difference_dt = finite_difference_dt
self.symmetric_finite_difference = symmetric_finite_difference
@property
def finite_difference_frameattr_name(self):
return self._finite_difference_frameattr_name
@finite_difference_frameattr_name.setter
def finite_difference_frameattr_name(self, value):
if value is None:
self._diff_attr_in_fromsys = self._diff_attr_in_tosys = False
else:
diff_attr_in_fromsys = value in self.fromsys.frame_attributes
diff_attr_in_tosys = value in self.tosys.frame_attributes
if diff_attr_in_fromsys or diff_attr_in_tosys:
self._diff_attr_in_fromsys = diff_attr_in_fromsys
self._diff_attr_in_tosys = diff_attr_in_tosys
else:
raise ValueError('Frame attribute name {} is not a frame '
'attribute of {} or {}'.format(value,
self.fromsys,
self.tosys))
self._finite_difference_frameattr_name = value
def __call__(self, fromcoord, toframe):
from .representation import (CartesianRepresentation,
CartesianDifferential)
supcall = self.func
if fromcoord.data.differentials:
# this is the finite difference case
if callable(self.finite_difference_dt):
dt = self.finite_difference_dt(fromcoord, toframe)
else:
dt = self.finite_difference_dt
halfdt = dt/2
from_diffless = fromcoord.realize_frame(fromcoord.data.without_differentials())
reprwithoutdiff = supcall(from_diffless, toframe)
# first we use the existing differential to compute an offset due to
# the already-existing velocity, but in the new frame
fromcoord_cart = fromcoord.cartesian
if self.symmetric_finite_difference:
fwdxyz = (fromcoord_cart.xyz +
fromcoord_cart.differentials['s'].d_xyz*halfdt)
fwd = supcall(fromcoord.realize_frame(CartesianRepresentation(fwdxyz)), toframe)
backxyz = (fromcoord_cart.xyz -
fromcoord_cart.differentials['s'].d_xyz*halfdt)
back = supcall(fromcoord.realize_frame(CartesianRepresentation(backxyz)), toframe)
else:
fwdxyz = (fromcoord_cart.xyz +
fromcoord_cart.differentials['s'].d_xyz*dt)
fwd = supcall(fromcoord.realize_frame(CartesianRepresentation(fwdxyz)), toframe)
back = reprwithoutdiff
diffxyz = (fwd.cartesian - back.cartesian).xyz / dt
# now we compute the "induced" velocities due to any movement in
# the frame itself over time
attrname = self.finite_difference_frameattr_name
if attrname is not None:
if self.symmetric_finite_difference:
if self._diff_attr_in_fromsys:
kws = {attrname: getattr(from_diffless, attrname) + halfdt}
from_diffless_fwd = from_diffless.replicate(**kws)
else:
from_diffless_fwd = from_diffless
if self._diff_attr_in_tosys:
kws = {attrname: getattr(toframe, attrname) + halfdt}
fwd_frame = toframe.replicate_without_data(**kws)
else:
fwd_frame = toframe
fwd = supcall(from_diffless_fwd, fwd_frame)
if self._diff_attr_in_fromsys:
kws = {attrname: getattr(from_diffless, attrname) - halfdt}
from_diffless_back = from_diffless.replicate(**kws)
else:
from_diffless_back = from_diffless
if self._diff_attr_in_tosys:
kws = {attrname: getattr(toframe, attrname) - halfdt}
back_frame = toframe.replicate_without_data(**kws)
else:
back_frame = toframe
back = supcall(from_diffless_back, back_frame)
else:
if self._diff_attr_in_fromsys:
kws = {attrname: getattr(from_diffless, attrname) + dt}
from_diffless_fwd = from_diffless.replicate(**kws)
else:
from_diffless_fwd = from_diffless
if self._diff_attr_in_tosys:
kws = {attrname: getattr(toframe, attrname) + dt}
fwd_frame = toframe.replicate_without_data(**kws)
else:
fwd_frame = toframe
fwd = supcall(from_diffless_fwd, fwd_frame)
back = reprwithoutdiff
diffxyz += (fwd.cartesian - back.cartesian).xyz / dt
newdiff = CartesianDifferential(diffxyz)
reprwithdiff = reprwithoutdiff.data.to_cartesian().with_differentials(newdiff)
return reprwithoutdiff.realize_frame(reprwithdiff)
else:
return supcall(fromcoord, toframe)
class BaseAffineTransform(CoordinateTransform):
"""Base class for common functionality between the ``AffineTransform``-type
subclasses.
This base class is needed because ``AffineTransform`` and the matrix
transform classes share the ``_apply_transform()`` method, but have
different ``__call__()`` methods. ``StaticMatrixTransform`` passes in a
matrix stored as a class attribute, and both of the matrix transforms pass
in ``None`` for the offset. Hence, user subclasses would likely want to
subclass this (rather than ``AffineTransform``) if they want to provide
alternative transformations using this machinery.
"""
def _apply_transform(self, fromcoord, matrix, offset):
from .representation import (UnitSphericalRepresentation,
CartesianDifferential,
SphericalDifferential,
SphericalCosLatDifferential,
RadialDifferential)
data = fromcoord.data
has_velocity = 's' in data.differentials
# list of unit differentials
_unit_diffs = (SphericalDifferential._unit_differential,
SphericalCosLatDifferential._unit_differential)
unit_vel_diff = (has_velocity and
isinstance(data.differentials['s'], _unit_diffs))
rad_vel_diff = (has_velocity and
isinstance(data.differentials['s'], RadialDifferential))
# Some initial checking to short-circuit doing any re-representation if
# we're going to fail anyways:
if isinstance(data, UnitSphericalRepresentation) and offset is not None:
raise TypeError("Position information stored on coordiante frame "
"is insufficient to do a full-space position "
"transformation (representation class: {0})"
.format(data.__class__))
elif (has_velocity and (unit_vel_diff or rad_vel_diff) and
offset is not None and 's' in offset.differentials):
# Coordinate has a velocity, but it is not a full-space velocity
# that we need to do a velocity offset
raise TypeError("Velocity information stored on coordinate frame "
"is insufficient to do a full-space velocity "
"transformation (differential class: {0})"
.format(data.differentials['s'].__class__))
elif len(data.differentials) > 1:
# We should never get here because the frame initializer shouldn't
# allow more differentials, but this just adds protection for
# subclasses that somehow skip the checks
raise ValueError("Representation passed to AffineTransform contains"
" multiple associated differentials. Only a single"
" differential with velocity units is presently"
" supported (differentials: {0})."
.format(str(data.differentials)))
# If the representation is a UnitSphericalRepresentation, and this is
# just a MatrixTransform, we have to try to turn the differential into a
# Unit version of the differential (if no radial velocity) or a
# sphericaldifferential with zero proper motion (if only a radial
# velocity) so that the matrix operation works
if (has_velocity and isinstance(data, UnitSphericalRepresentation) and
not unit_vel_diff and not rad_vel_diff):
# retrieve just velocity differential
unit_diff = data.differentials['s'].represent_as(
data.differentials['s']._unit_differential, data)
data = data.with_differentials({'s': unit_diff}) # updates key
# If it's a RadialDifferential, we flat-out ignore the differentials
# This is because, by this point (past the validation above), we can
# only possibly be doing a rotation-only transformation, and that
# won't change the radial differential. We later add it back in
elif rad_vel_diff:
data = data.without_differentials()
# Convert the representation and differentials to cartesian without
# having them attached to a frame
rep = data.to_cartesian()
diffs = dict([(k, diff.represent_as(CartesianDifferential, data))
for k, diff in data.differentials.items()])
rep = rep.with_differentials(diffs)
# Only do transform if matrix is specified. This is for speed in
# transformations that only specify an offset (e.g., LSR)
if matrix is not None:
# Note: this applies to both representation and differentials
rep = rep.transform(matrix)
# TODO: if we decide to allow arithmetic between representations that
# contain differentials, this can be tidied up
if offset is not None:
newrep = (rep.without_differentials() +
offset.without_differentials())
else:
newrep = rep.without_differentials()
# We need a velocity (time derivative) and, for now, are strict: the
# representation can only contain a velocity differential and no others.
if has_velocity and not rad_vel_diff:
veldiff = rep.differentials['s'] # already in Cartesian form
if offset is not None and 's' in offset.differentials:
veldiff = veldiff + offset.differentials['s']
newrep = newrep.with_differentials({'s': veldiff})
if isinstance(fromcoord.data, UnitSphericalRepresentation):
# Special-case this because otherwise the return object will think
# it has a valid distance with the default return (a
# CartesianRepresentation instance)
if has_velocity and not unit_vel_diff and not rad_vel_diff:
# We have to first represent as the Unit types we converted to,
# then put the d_distance information back in to the
# differentials and re-represent as their original forms
newdiff = newrep.differentials['s']
_unit_cls = fromcoord.data.differentials['s']._unit_differential
newdiff = newdiff.represent_as(_unit_cls, newrep)
kwargs = dict([(comp, getattr(newdiff, comp))
for comp in newdiff.components])
kwargs['d_distance'] = fromcoord.data.differentials['s'].d_distance
diffs = {'s': fromcoord.data.differentials['s'].__class__(
copy=False, **kwargs)}
elif has_velocity and unit_vel_diff:
newdiff = newrep.differentials['s'].represent_as(
fromcoord.data.differentials['s'].__class__, newrep)
diffs = {'s': newdiff}
else:
diffs = newrep.differentials
newrep = newrep.represent_as(fromcoord.data.__class__) # drops diffs
newrep = newrep.with_differentials(diffs)
elif has_velocity and unit_vel_diff:
# Here, we're in the case where the representation is not
# UnitSpherical, but the differential *is* one of the UnitSpherical
# types. We have to convert back to that differential class or the
# resulting frame will think it has a valid radial_velocity. This
# can probably be cleaned up: we currently have to go through the
# dimensional version of the differential before representing as the
# unit differential so that the units work out (the distance length
# unit shouldn't appear in the resulting proper motions)
diff_cls = fromcoord.data.differentials['s'].__class__
newrep = newrep.represent_as(fromcoord.data.__class__,
diff_cls._dimensional_differential)
newrep = newrep.represent_as(fromcoord.data.__class__, diff_cls)
# We pulled the radial differential off of the representation
# earlier, so now we need to put it back. But, in order to do that, we
# have to turn the representation into a repr that is compatible with
# having a RadialDifferential
if has_velocity and rad_vel_diff:
newrep = newrep.represent_as(fromcoord.data.__class__)
newrep = newrep.with_differentials(
{'s': fromcoord.data.differentials['s']})
return newrep
class AffineTransform(BaseAffineTransform):
"""
A coordinate transformation specified as a function that yields a 3 x 3
cartesian transformation matrix and a tuple of displacement vectors.
See `~astropy.coordinates.builtin_frames.galactocentric.Galactocentric` for
an example.
Parameters
----------
transform_func : callable
A callable that has the signature ``transform_func(fromcoord, toframe)``
and returns: a (3, 3) matrix that operates on ``fromcoord`` in a
Cartesian representation, and a ``CartesianRepresentation`` with
(optionally) an attached velocity ``CartesianDifferential`` to represent
a translation and offset in velocity to apply after the matrix
operation.
fromsys : class
The coordinate frame class to start from.
tosys : class
The coordinate frame class to transform into.
priority : number
The priority if this transform when finding the shortest
coordinate transform path - large numbers are lower priorities.
register_graph : `TransformGraph` or `None`
A graph to register this transformation with on creation, or
`None` to leave it unregistered.
Raises
------
TypeError
If ``transform_func`` is not callable
"""
def __init__(self, transform_func, fromsys, tosys, priority=1,
register_graph=None):
if not callable(transform_func):
raise TypeError('transform_func is not callable')
self.transform_func = transform_func
super().__init__(fromsys, tosys, priority=priority,
register_graph=register_graph)
def __call__(self, fromcoord, toframe):
M, vec = self.transform_func(fromcoord, toframe)
newrep = self._apply_transform(fromcoord, M, vec)
return toframe.realize_frame(newrep)
class StaticMatrixTransform(BaseAffineTransform):
"""
A coordinate transformation defined as a 3 x 3 cartesian
transformation matrix.
This is distinct from DynamicMatrixTransform in that this kind of matrix is
independent of frame attributes. That is, it depends *only* on the class of
the frame.
Parameters
----------
matrix : array-like or callable
A 3 x 3 matrix for transforming 3-vectors. In most cases will
be unitary (although this is not strictly required). If a callable,
will be called *with no arguments* to get the matrix.
fromsys : class
The coordinate frame class to start from.
tosys : class
The coordinate frame class to transform into.
priority : number
The priority if this transform when finding the shortest
coordinate transform path - large numbers are lower priorities.
register_graph : `TransformGraph` or `None`
A graph to register this transformation with on creation, or
`None` to leave it unregistered.
Raises
------
ValueError
If the matrix is not 3 x 3
"""
def __init__(self, matrix, fromsys, tosys, priority=1, register_graph=None):
if callable(matrix):
matrix = matrix()
self.matrix = np.array(matrix)
if self.matrix.shape != (3, 3):
raise ValueError('Provided matrix is not 3 x 3')
super().__init__(fromsys, tosys, priority=priority,
register_graph=register_graph)
def __call__(self, fromcoord, toframe):
newrep = self._apply_transform(fromcoord, self.matrix, None)
return toframe.realize_frame(newrep)
class DynamicMatrixTransform(BaseAffineTransform):
"""
A coordinate transformation specified as a function that yields a
3 x 3 cartesian transformation matrix.
This is similar to, but distinct from StaticMatrixTransform, in that the
matrix for this class might depend on frame attributes.
Parameters
----------
matrix_func : callable
A callable that has the signature ``matrix_func(fromcoord, toframe)`` and
returns a 3 x 3 matrix that converts ``fromcoord`` in a cartesian
representation to the new coordinate system.
fromsys : class
The coordinate frame class to start from.
tosys : class
The coordinate frame class to transform into.
priority : number
The priority if this transform when finding the shortest
coordinate transform path - large numbers are lower priorities.
register_graph : `TransformGraph` or `None`
A graph to register this transformation with on creation, or
`None` to leave it unregistered.
Raises
------
TypeError
If ``matrix_func`` is not callable
"""
def __init__(self, matrix_func, fromsys, tosys, priority=1,
register_graph=None):
if not callable(matrix_func):
raise TypeError('matrix_func is not callable')
self.matrix_func = matrix_func
def _transform_func(fromcoord, toframe):
return self.matrix_func(fromcoord, toframe), None
super().__init__(fromsys, tosys, priority=priority,
register_graph=register_graph)
def __call__(self, fromcoord, toframe):
M = self.matrix_func(fromcoord, toframe)
newrep = self._apply_transform(fromcoord, M, None)
return toframe.realize_frame(newrep)
class CompositeTransform(CoordinateTransform):
"""
A transformation constructed by combining together a series of single-step
transformations.
Note that the intermediate frame objects are constructed using any frame
attributes in ``toframe`` or ``fromframe`` that overlap with the intermediate
frame (``toframe`` favored over ``fromframe`` if there's a conflict). Any frame
attributes that are not present use the defaults.
Parameters
----------
transforms : sequence of `CoordinateTransform` objects
The sequence of transformations to apply.
fromsys : class
The coordinate frame class to start from.
tosys : class
The coordinate frame class to transform into.
priority : number
The priority if this transform when finding the shortest
coordinate transform path - large numbers are lower priorities.
register_graph : `TransformGraph` or `None`
A graph to register this transformation with on creation, or
`None` to leave it unregistered.
collapse_static_mats : bool
If `True`, consecutive `StaticMatrixTransform` will be collapsed into a
single transformation to speed up the calculation.
"""
def __init__(self, transforms, fromsys, tosys, priority=1,
register_graph=None, collapse_static_mats=True):
super().__init__(fromsys, tosys, priority=priority,
register_graph=register_graph)
if collapse_static_mats:
transforms = self._combine_statics(transforms)
self.transforms = tuple(transforms)
def _combine_statics(self, transforms):
"""
Combines together sequences of `StaticMatrixTransform`s into a single
transform and returns it.
"""
newtrans = []
for currtrans in transforms:
lasttrans = newtrans[-1] if len(newtrans) > 0 else None
if (isinstance(lasttrans, StaticMatrixTransform) and
isinstance(currtrans, StaticMatrixTransform)):
combinedmat = np.dot(lasttrans.matrix, currtrans.matrix)
newtrans[-1] = StaticMatrixTransform(combinedmat,
lasttrans.fromsys,
currtrans.tosys)
else:
newtrans.append(currtrans)
return newtrans
def __call__(self, fromcoord, toframe):
curr_coord = fromcoord
for t in self.transforms:
# build an intermediate frame with attributes taken from either
# `fromframe`, or if not there, `toframe`, or if not there, use
# the defaults
# TODO: caching this information when creating the transform may
# speed things up a lot
frattrs = {}
for inter_frame_attr_nm in t.tosys.get_frame_attr_names():
if hasattr(toframe, inter_frame_attr_nm):
attr = getattr(toframe, inter_frame_attr_nm)
frattrs[inter_frame_attr_nm] = attr
elif hasattr(fromcoord, inter_frame_attr_nm):
attr = getattr(fromcoord, inter_frame_attr_nm)
frattrs[inter_frame_attr_nm] = attr
curr_toframe = t.tosys(**frattrs)
curr_coord = t(curr_coord, curr_toframe)
# this is safe even in the case where self.transforms is empty, because
# coordinate objects are immutible, so copying is not needed
return curr_coord
# map class names to colorblind-safe colors
trans_to_color = OrderedDict()
trans_to_color[AffineTransform] = '#555555' # gray
trans_to_color[FunctionTransform] = '#783001' # dark red-ish/brown
trans_to_color[FunctionTransformWithFiniteDifference] = '#d95f02' # red-ish
trans_to_color[StaticMatrixTransform] = '#7570b3' # blue-ish
trans_to_color[DynamicMatrixTransform] = '#1b9e77' # green-ish
|
dedea3bb4b2d2fe07615730d26ab075fbd3d026d2216b15e0c2855afc11427fe | # Licensed under a 3-clause BSD style license - see LICENSE.rst
def get_package_data():
return {'astropy.coordinates.tests.accuracy': ['*.csv'],
'astropy.coordinates': ['data/*.dat', 'data/sites.json']}
|
798809da668b19516dad126da8e91cd0929855535ce5c79eef2b3331ba85e8a4 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module contains the classes and utility functions for distance and
cartesian coordinates.
"""
import numpy as np
from .. import units as u
from .angles import Angle
__all__ = ['Distance']
__doctest_requires__ = {'*': ['scipy.integrate']}
class Distance(u.SpecificTypeQuantity):
"""
A one-dimensional distance.
This can be initialized in one of four ways:
* A distance ``value`` (array or float) and a ``unit``
* A `~astropy.units.Quantity` object
* A redshift and (optionally) a cosmology.
* Providing a distance modulus
Parameters
----------
value : scalar or `~astropy.units.Quantity`.
The value of this distance.
unit : `~astropy.units.UnitBase`
The units for this distance, *if* ``value`` is not a
`~astropy.units.Quantity`. Must have dimensions of distance.
z : float
A redshift for this distance. It will be converted to a distance
by computing the luminosity distance for this redshift given the
cosmology specified by ``cosmology``. Must be given as a keyword
argument.
cosmology : ``Cosmology`` or `None`
A cosmology that will be used to compute the distance from ``z``.
If `None`, the current cosmology will be used (see
`astropy.cosmology` for details).
distmod : float or `~astropy.units.Quantity`
The distance modulus for this distance. Note that if ``unit`` is not
provided, a guess will be made at the unit between AU, pc, kpc, and Mpc.
parallax : `~astropy.units.Quantity` or `~astropy.coordinates.Angle`
The parallax in angular units.
dtype : `~numpy.dtype`, optional
See `~astropy.units.Quantity`.
copy : bool, optional
See `~astropy.units.Quantity`.
order : {'C', 'F', 'A'}, optional
See `~astropy.units.Quantity`.
subok : bool, optional
See `~astropy.units.Quantity`.
ndmin : int, optional
See `~astropy.units.Quantity`.
allow_negative : bool, optional
Whether to allow negative distances (which are possible is some
cosmologies). Default: ``False``.
Raises
------
`~astropy.units.UnitsError`
If the ``unit`` is not a distance.
ValueError
If value specified is less than 0 and ``allow_negative=False``.
If ``z`` is provided with a ``unit`` or ``cosmology`` is provided
when ``z`` is *not* given, or ``value`` is given as well as ``z``.
Examples
--------
>>> from astropy import units as u
>>> from astropy import cosmology
>>> from astropy.cosmology import WMAP5, WMAP7
>>> cosmology.set_current(WMAP7)
>>> d1 = Distance(10, u.Mpc)
>>> d2 = Distance(40, unit=u.au)
>>> d3 = Distance(value=5, unit=u.kpc)
>>> d4 = Distance(z=0.23)
>>> d5 = Distance(z=0.23, cosmology=WMAP5)
>>> d6 = Distance(distmod=24.47)
>>> d7 = Distance(Distance(10 * u.Mpc))
>>> d8 = Distance(parallax=21.34*u.mas)
"""
_equivalent_unit = u.m
_include_easy_conversion_members = True
def __new__(cls, value=None, unit=None, z=None, cosmology=None,
distmod=None, parallax=None, dtype=None, copy=True, order=None,
subok=False, ndmin=0, allow_negative=False):
if z is not None:
if value is not None or distmod is not None:
raise ValueError('Should given only one of `value`, `z` '
'or `distmod` in Distance constructor.')
if cosmology is None:
from ..cosmology import default_cosmology
cosmology = default_cosmology.get()
value = cosmology.luminosity_distance(z)
# Continue on to take account of unit and other arguments
# but a copy is already made, so no longer necessary
copy = False
else:
if cosmology is not None:
raise ValueError('A `cosmology` was given but `z` was not '
'provided in Distance constructor')
value_msg = ('Should given only one of `value`, `z`, `distmod`, or '
'`parallax` in Distance constructor.')
n_not_none = np.sum([x is not None
for x in [value, z, distmod, parallax]])
if n_not_none > 1:
raise ValueError(value_msg)
if distmod is not None:
value = cls._distmod_to_pc(distmod)
if unit is None:
# if the unit is not specified, guess based on the mean of
# the log of the distance
meanlogval = np.log10(value.value).mean()
if meanlogval > 6:
unit = u.Mpc
elif meanlogval > 3:
unit = u.kpc
elif meanlogval < -3: # ~200 AU
unit = u.AU
else:
unit = u.pc
# Continue on to take account of unit and other arguments
# but a copy is already made, so no longer necessary
copy = False
elif parallax is not None:
value = parallax.to(u.pc, equivalencies=u.parallax()).value
unit = u.pc
# Continue on to take account of unit and other arguments
# but a copy is already made, so no longer necessary
copy = False
elif value is None:
raise ValueError('None of `value`, `z`, `distmod`, or '
'`parallax` were given to Distance '
'constructor')
# now we have arguments like for a Quantity, so let it do the work
distance = super().__new__(
cls, value, unit, dtype=dtype, copy=copy, order=order,
subok=subok, ndmin=ndmin)
if not allow_negative and np.any(distance.value < 0):
raise ValueError("Distance must be >= 0. Use the argument "
"'allow_negative=True' to allow negative values.")
return distance
@property
def z(self):
"""Short for ``self.compute_z()``"""
return self.compute_z()
def compute_z(self, cosmology=None):
"""
The redshift for this distance assuming its physical distance is
a luminosity distance.
Parameters
----------
cosmology : ``Cosmology`` or `None`
The cosmology to assume for this calculation, or `None` to use the
current cosmology (see `astropy.cosmology` for details).
Returns
-------
z : float
The redshift of this distance given the provided ``cosmology``.
"""
if cosmology is None:
from ..cosmology import default_cosmology
cosmology = default_cosmology.get()
from ..cosmology import z_at_value
return z_at_value(cosmology.luminosity_distance, self, ztol=1.e-10)
@property
def distmod(self):
"""The distance modulus as a `~astropy.units.Quantity`"""
val = 5. * np.log10(self.to_value(u.pc)) - 5.
return u.Quantity(val, u.mag, copy=False)
@classmethod
def _distmod_to_pc(cls, dm):
dm = u.Quantity(dm, u.mag)
return cls(10 ** ((dm.value + 5) / 5.), u.pc, copy=False)
@property
def parallax(self):
"""The parallax angle as an `~astropy.coordinates.Angle` object"""
return Angle(self.to(u.milliarcsecond, u.parallax()))
def _convert_to_and_validate_length_unit(unit, allow_dimensionless=False):
"""
raises UnitsError if not a length unit
"""
try:
unit = u.Unit(unit)
assert (unit.is_equivalent(u.kpc) or
allow_dimensionless and unit == u.dimensionless_unscaled)
except (TypeError, AssertionError):
raise u.UnitsError('Unit "{0}" is not a length type'.format(unit))
return unit
|
a5a361ccbc7e2e74fc6aaf2c39abf96adb1bfe38aa9fa31b11f95dcc1596748b | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module contains convenience functions for coordinate-related functionality.
This is generally just wrapping around the object-oriented coordinates
framework, but it is useful for some users who are used to more functional
interfaces.
"""
import numpy as np
from .. import units as u
from ..constants import c
from .. import _erfa as erfa
from ..io import ascii
from ..utils import isiterable, data
from .sky_coordinate import SkyCoord
from .builtin_frames import GCRS, PrecessedGeocentric
from .representation import SphericalRepresentation, CartesianRepresentation
from .builtin_frames.utils import get_jd12
__all__ = ['cartesian_to_spherical', 'spherical_to_cartesian', 'get_sun',
'concatenate', 'get_constellation']
def cartesian_to_spherical(x, y, z):
"""
Converts 3D rectangular cartesian coordinates to spherical polar
coordinates.
Note that the resulting angles are latitude/longitude or
elevation/azimuthal form. I.e., the origin is along the equator
rather than at the north pole.
.. note::
This function simply wraps functionality provided by the
`~astropy.coordinates.CartesianRepresentation` and
`~astropy.coordinates.SphericalRepresentation` classes. In general,
for both performance and readability, we suggest using these classes
directly. But for situations where a quick one-off conversion makes
sense, this function is provided.
Parameters
----------
x : scalar, array-like, or `~astropy.units.Quantity`
The first cartesian coordinate.
y : scalar, array-like, or `~astropy.units.Quantity`
The second cartesian coordinate.
z : scalar, array-like, or `~astropy.units.Quantity`
The third cartesian coordinate.
Returns
-------
r : `~astropy.units.Quantity`
The radial coordinate (in the same units as the inputs).
lat : `~astropy.units.Quantity`
The latitude in radians
lon : `~astropy.units.Quantity`
The longitude in radians
"""
if not hasattr(x, 'unit'):
x = x * u.dimensionless_unscaled
if not hasattr(y, 'unit'):
y = y * u.dimensionless_unscaled
if not hasattr(z, 'unit'):
z = z * u.dimensionless_unscaled
cart = CartesianRepresentation(x, y, z)
sph = cart.represent_as(SphericalRepresentation)
return sph.distance, sph.lat, sph.lon
def spherical_to_cartesian(r, lat, lon):
"""
Converts spherical polar coordinates to rectangular cartesian
coordinates.
Note that the input angles should be in latitude/longitude or
elevation/azimuthal form. I.e., the origin is along the equator
rather than at the north pole.
.. note::
This is a low-level function used internally in
`astropy.coordinates`. It is provided for users if they really
want to use it, but it is recommended that you use the
`astropy.coordinates` coordinate systems.
Parameters
----------
r : scalar, array-like, or `~astropy.units.Quantity`
The radial coordinate (in the same units as the inputs).
lat : scalar, array-like, or `~astropy.units.Quantity`
The latitude (in radians if array or scalar)
lon : scalar, array-like, or `~astropy.units.Quantity`
The longitude (in radians if array or scalar)
Returns
-------
x : float or array
The first cartesian coordinate.
y : float or array
The second cartesian coordinate.
z : float or array
The third cartesian coordinate.
"""
if not hasattr(r, 'unit'):
r = r * u.dimensionless_unscaled
if not hasattr(lat, 'unit'):
lat = lat * u.radian
if not hasattr(lon, 'unit'):
lon = lon * u.radian
sph = SphericalRepresentation(distance=r, lat=lat, lon=lon)
cart = sph.represent_as(CartesianRepresentation)
return cart.x, cart.y, cart.z
def get_sun(time):
"""
Determines the location of the sun at a given time (or times, if the input
is an array `~astropy.time.Time` object), in geocentric coordinates.
Parameters
----------
time : `~astropy.time.Time`
The time(s) at which to compute the location of the sun.
Returns
-------
newsc : `~astropy.coordinates.SkyCoord`
The location of the sun as a `~astropy.coordinates.SkyCoord` in the
`~astropy.coordinates.GCRS` frame.
Notes
-----
The algorithm for determining the sun/earth relative position is based
on the simplified version of VSOP2000 that is part of ERFA. Compared to
JPL's ephemeris, it should be good to about 4 km (in the Sun-Earth
vector) from 1900-2100 C.E., 8 km for the 1800-2200 span, and perhaps
250 km over the 1000-3000.
"""
earth_pv_helio, earth_pv_bary = erfa.epv00(*get_jd12(time, 'tdb'))
# We have to manually do aberration because we're outputting directly into
# GCRS
earth_p = earth_pv_helio[..., 0, :]
earth_v = earth_pv_bary[..., 1, :]
# convert barycentric velocity to units of c, but keep as array for passing in to erfa
earth_v /= c.to_value(u.au/u.d)
dsun = np.sqrt(np.sum(earth_p**2, axis=-1))
invlorentz = (1-np.sum(earth_v**2, axis=-1))**0.5
properdir = erfa.ab(earth_p/dsun.reshape(dsun.shape + (1,)),
-earth_v, dsun, invlorentz)
cartrep = CartesianRepresentation(x=-dsun*properdir[..., 0] * u.AU,
y=-dsun*properdir[..., 1] * u.AU,
z=-dsun*properdir[..., 2] * u.AU)
return SkyCoord(cartrep, frame=GCRS(obstime=time))
def concatenate(coords):
"""
Combine multiple coordinate objects into a single
`~astropy.coordinates.SkyCoord`.
"Coordinate objects" here mean frame objects with data,
`~astropy.coordinates.SkyCoord`, or representation objects. Currently,
they must all be in the same frame, but in a future version this may be
relaxed to allow inhomogenous sequences of objects.
Parameters
----------
coords : sequence of coordinate objects
The objects to concatenate
Returns
-------
cskycoord : SkyCoord
A single sky coordinate with its data set to the concatenation of all
the elements in ``coords``
"""
if getattr(coords, 'isscalar', False) or not isiterable(coords):
raise TypeError('The argument to concatenate must be iterable')
return SkyCoord(coords)
# global dictionary that caches repeatedly-needed info for get_constellation
_constellation_data = {}
def get_constellation(coord, short_name=False, constellation_list='iau'):
"""
Determines the constellation(s) a given coordinate object contains.
Parameters
----------
coord : coordinate object
The object to determine the constellation of.
short_name : bool
If True, the returned names are the IAU-sanctioned abbreviated
names. Otherwise, full names for the constellations are used.
constellation_list : str
The set of constellations to use. Currently only ``'iau'`` is
supported, meaning the 88 "modern" constellations endorsed by the IAU.
Returns
-------
constellation : str or string array
If ``coords`` contains a scalar coordinate, returns the name of the
constellation. If it is an array coordinate object, it returns an array
of names.
Notes
-----
To determine which constellation a point on the sky is in, this precesses
to B1875, and then uses the Delporte boundaries of the 88 modern
constellations, as tabulated by
`Roman 1987 <http://cdsarc.u-strasbg.fr/viz-bin/Cat?VI/42>`_.
"""
if constellation_list != 'iau':
raise ValueError("only 'iau' us currently supported for constellation_list")
# read the data files and cache them if they haven't been already
if not _constellation_data:
cdata = data.get_pkg_data_contents('data/constellation_data_roman87.dat')
ctable = ascii.read(cdata, names=['ral', 'rau', 'decl', 'name'])
cnames = data.get_pkg_data_contents('data/constellation_names.dat', encoding='UTF8')
cnames_short_to_long = dict([(l[:3], l[4:])
for l in cnames.split('\n')
if not l.startswith('#')])
cnames_long = np.array([cnames_short_to_long[nm] for nm in ctable['name']])
_constellation_data['ctable'] = ctable
_constellation_data['cnames_long'] = cnames_long
else:
ctable = _constellation_data['ctable']
cnames_long = _constellation_data['cnames_long']
isscalar = coord.isscalar
# if it is geocentric, we reproduce the frame but with the 1875 equinox,
# which is where the constellations are defined
constel_coord = coord.transform_to(PrecessedGeocentric(equinox='B1875'))
if isscalar:
rah = constel_coord.ra.ravel().hour
decd = constel_coord.dec.ravel().deg
else:
rah = constel_coord.ra.hour
decd = constel_coord.dec.deg
constellidx = -np.ones(len(rah), dtype=int)
notided = constellidx == -1 # should be all
for i, row in enumerate(ctable):
msk = (row['ral'] < rah) & (rah < row['rau']) & (decd > row['decl'])
constellidx[notided & msk] = i
notided = constellidx == -1
if np.sum(notided) == 0:
break
else:
raise ValueError('Could not find constellation for coordinates {0}'.format(constel_coord[notided]))
if short_name:
names = ctable['name'][constellidx]
else:
names = cnames_long[constellidx]
if isscalar:
return names[0]
else:
return names
|
5f9f0e7a9d235aab16ed512b231e5ff1999418823991f61a2167ff5299f2c155 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Framework and base classes for coordinate frames/"low-level" coordinate
classes.
"""
# Standard library
import abc
import copy
import inspect
from collections import namedtuple, OrderedDict, defaultdict
import warnings
# Dependencies
import numpy as np
# Project
from ..utils.compat.misc import override__dir__
from ..utils.decorators import lazyproperty, format_doc
from ..utils.exceptions import AstropyWarning
from .. import units as u
from ..utils import (OrderedDescriptorContainer, ShapedLikeNDArray,
check_broadcast)
from .transformations import TransformGraph
from . import representation as r
from .angles import Angle
from .attributes import Attribute
# Import old names for Attributes so we don't break backwards-compatibility
# (some users rely on them being here, although that is not encouraged, as this
# is not the public API location -- see attributes.py).
from .attributes import (
TimeFrameAttribute, QuantityFrameAttribute,
EarthLocationAttribute, CoordinateAttribute,
CartesianRepresentationFrameAttribute) # pylint: disable=W0611
__all__ = ['BaseCoordinateFrame', 'frame_transform_graph',
'GenericFrame', 'RepresentationMapping']
# the graph used for all transformations between frames
frame_transform_graph = TransformGraph()
def _get_repr_cls(value):
"""
Return a valid representation class from ``value`` or raise exception.
"""
if value in r.REPRESENTATION_CLASSES:
value = r.REPRESENTATION_CLASSES[value]
elif (not isinstance(value, type) or
not issubclass(value, r.BaseRepresentation)):
raise ValueError(
'Representation is {0!r} but must be a BaseRepresentation class '
'or one of the string aliases {1}'.format(
value, list(r.REPRESENTATION_CLASSES)))
return value
def _get_diff_cls(value):
"""
Return a valid differential class from ``value`` or raise exception.
As originally created, this is only used in the SkyCoord initializer, so if
that is refactored, this function my no longer be necessary.
"""
if value in r.DIFFERENTIAL_CLASSES:
value = r.DIFFERENTIAL_CLASSES[value]
elif (not isinstance(value, type) or
not issubclass(value, r.BaseDifferential)):
raise ValueError(
'Differential is {0!r} but must be a BaseDifferential class '
'or one of the string aliases {1}'.format(
value, list(r.DIFFERENTIAL_CLASSES)))
return value
def _get_repr_classes(base, **differentials):
"""Get valid representation and differential classes.
Parameters
----------
base : str or `~astropy.coordinates.BaseRepresentation` subclass
class for the representation of the base coordinates. If a string,
it is looked up among the known representation classes.
**differentials : dict of str or `~astropy.coordinates.BaseDifferentials`
Keys are like for normal differentials, i.e., 's' for a first
derivative in time, etc. If an item is set to `None`, it will be
guessed from the base class.
Returns
-------
repr_classes : dict of subclasses
The base class is keyed by 'base'; the others by the keys of
``diffferentials``.
"""
base = _get_repr_cls(base)
repr_classes = {'base': base}
for name, differential_type in differentials.items():
if differential_type == 'base':
# We don't want to fail for this case.
differential_type = r.DIFFERENTIAL_CLASSES.get(base.get_name(), None)
elif differential_type in r.DIFFERENTIAL_CLASSES:
differential_type = r.DIFFERENTIAL_CLASSES[differential_type]
elif (differential_type is not None and
(not isinstance(differential_type, type) or
not issubclass(differential_type, r.BaseDifferential))):
raise ValueError(
'Differential is {0!r} but must be a BaseDifferential class '
'or one of the string aliases {1}'.format(
differential_type, list(r.DIFFERENTIAL_CLASSES)))
repr_classes[name] = differential_type
return repr_classes
def _normalize_representation_type(kwargs):
""" This is added for backwards compatibility: if the user specifies the
old-style argument ``representation``, add it back in to the kwargs dict
as ``representation_type``.
"""
if 'representation' in kwargs:
if 'representation_type' in kwargs:
raise ValueError("Both `representation` and `representation_type` "
"were passed to a frame initializer. Please use "
"only `representation_type` (`representation` is "
"now pending deprecation).")
kwargs['representation_type'] = kwargs.pop('representation')
# Need to subclass ABCMeta as well, so that this meta class can be combined
# with ShapedLikeNDArray below (which is an ABC); without it, one gets
# "TypeError: metaclass conflict: the metaclass of a derived class must be a
# (non-strict) subclass of the metaclasses of all its bases"
class FrameMeta(OrderedDescriptorContainer, abc.ABCMeta):
def __new__(mcls, name, bases, members):
if 'default_representation' in members:
default_repr = members.pop('default_representation')
found_default_repr = True
else:
default_repr = None
found_default_repr = False
if 'default_differential' in members:
default_diff = members.pop('default_differential')
found_default_diff = True
else:
default_diff = None
found_default_diff = False
if 'frame_specific_representation_info' in members:
repr_info = members.pop('frame_specific_representation_info')
found_repr_info = True
else:
repr_info = None
found_repr_info = False
# somewhat hacky, but this is the best way to get the MRO according to
# https://mail.python.org/pipermail/python-list/2002-December/167861.html
tmp_cls = super().__new__(mcls, name, bases, members)
# now look through the whole MRO for the class attributes, raw for
# frame_attr_names, and leading underscore for others
for m in (c.__dict__ for c in tmp_cls.__mro__):
if not found_default_repr and '_default_representation' in m:
default_repr = m['_default_representation']
found_default_repr = True
if not found_default_diff and '_default_differential' in m:
default_diff = m['_default_differential']
found_default_diff = True
if (not found_repr_info and
'_frame_specific_representation_info' in m):
# create a copy of the dict so we don't mess with the contents
repr_info = m['_frame_specific_representation_info'].copy()
found_repr_info = True
if found_default_repr and found_default_diff and found_repr_info:
break
else:
raise ValueError(
'Could not find all expected BaseCoordinateFrame class '
'attributes. Are you mis-using FrameMeta?')
# Unless overridden via `frame_specific_representation_info`, velocity
# name defaults are (see also docstring for BaseCoordinateFrame):
# * ``pm_{lon}_cos{lat}``, ``pm_{lat}`` for
# `SphericalCosLatDifferential` proper motion components
# * ``pm_{lon}``, ``pm_{lat}`` for `SphericalDifferential` proper
# motion components
# * ``radial_velocity`` for any `d_distance` component
# * ``v_{x,y,z}`` for `CartesianDifferential` velocity components
# where `{lon}` and `{lat}` are the frame names of the angular
# components.
if repr_info is None:
repr_info = {}
# the tuple() call below is necessary because if it is not there,
# the iteration proceeds in a difficult-to-predict manner in the
# case that one of the class objects hash is such that it gets
# revisited by the iteration. The tuple() call prevents this by
# making the items iterated over fixed regardless of how the dict
# changes
for cls_or_name in tuple(repr_info.keys()):
if isinstance(cls_or_name, str):
# TODO: this provides a layer of backwards compatibility in
# case the key is a string, but now we want explicit classes.
cls = _get_repr_cls(cls_or_name)
repr_info[cls] = repr_info.pop(cls_or_name)
# The default spherical names are 'lon' and 'lat'
repr_info.setdefault(r.SphericalRepresentation,
[RepresentationMapping('lon', 'lon'),
RepresentationMapping('lat', 'lat')])
sph_component_map = {m.reprname: m.framename
for m in repr_info[r.SphericalRepresentation]}
repr_info.setdefault(r.SphericalCosLatDifferential, [
RepresentationMapping(
'd_lon_coslat',
'pm_{lon}_cos{lat}'.format(**sph_component_map),
u.mas/u.yr),
RepresentationMapping('d_lat',
'pm_{lat}'.format(**sph_component_map),
u.mas/u.yr),
RepresentationMapping('d_distance', 'radial_velocity',
u.km/u.s)
])
repr_info.setdefault(r.SphericalDifferential, [
RepresentationMapping('d_lon',
'pm_{lon}'.format(**sph_component_map),
u.mas/u.yr),
RepresentationMapping('d_lat',
'pm_{lat}'.format(**sph_component_map),
u.mas/u.yr),
RepresentationMapping('d_distance', 'radial_velocity',
u.km/u.s)
])
repr_info.setdefault(r.CartesianDifferential, [
RepresentationMapping('d_x', 'v_x', u.km/u.s),
RepresentationMapping('d_y', 'v_y', u.km/u.s),
RepresentationMapping('d_z', 'v_z', u.km/u.s)])
# Unit* classes should follow the same naming conventions
# TODO: this adds some unnecessary mappings for the Unit classes, so
# this could be cleaned up, but in practice doesn't seem to have any
# negative side effects
repr_info.setdefault(r.UnitSphericalRepresentation,
repr_info[r.SphericalRepresentation])
repr_info.setdefault(r.UnitSphericalCosLatDifferential,
repr_info[r.SphericalCosLatDifferential])
repr_info.setdefault(r.UnitSphericalDifferential,
repr_info[r.SphericalDifferential])
# Make read-only properties for the frame class attributes that should
# be read-only to make them immutable after creation.
# We copy attributes instead of linking to make sure there's no
# accidental cross-talk between classes
mcls.readonly_prop_factory(members, 'default_representation',
default_repr)
mcls.readonly_prop_factory(members, 'default_differential',
default_diff)
mcls.readonly_prop_factory(members,
'frame_specific_representation_info',
copy.deepcopy(repr_info))
# now set the frame name as lower-case class name, if it isn't explicit
if 'name' not in members:
members['name'] = name.lower()
return super().__new__(mcls, name, bases, members)
@staticmethod
def readonly_prop_factory(members, attr, value):
private_attr = '_' + attr
def getter(self):
return getattr(self, private_attr)
members[private_attr] = value
members[attr] = property(getter)
_RepresentationMappingBase = \
namedtuple('RepresentationMapping',
('reprname', 'framename', 'defaultunit'))
class RepresentationMapping(_RepresentationMappingBase):
"""
This `~collections.namedtuple` is used with the
``frame_specific_representation_info`` attribute to tell frames what
attribute names (and default units) to use for a particular representation.
``reprname`` and ``framename`` should be strings, while ``defaultunit`` can
be either an astropy unit, the string ``'recommended'`` (to use whatever
the representation's ``recommended_units`` is), or None (to indicate that
no unit mapping should be done).
"""
def __new__(cls, reprname, framename, defaultunit='recommended'):
# this trick just provides some defaults
return super().__new__(cls, reprname, framename, defaultunit)
base_doc = """{__doc__}
Parameters
----------
data : `BaseRepresentation` subclass instance
A representation object or ``None`` to have no data (or use the
coordinate component arguments, see below).
{components}
representation_type : `BaseRepresentation` subclass, str, optional
A representation class or string name of a representation class. This
sets the expected input representation class, thereby changing the
expected keyword arguments for the data passed in. For example, passing
``representation_type='cartesian'`` will make the classes expect
position data with cartesian names, i.e. ``x, y, z`` in most cases.
differential_type : `BaseDifferential` subclass, str, dict, optional
A differential class or dictionary of differential classes (currently
only a velocity differential with key 's' is supported). This sets the
expected input differential class, thereby changing the expected keyword
arguments of the data passed in. For example, passing
``differential_type='cartesian'`` will make the classes expect velocity
data with the argument names ``v_x, v_y, v_z``.
copy : bool, optional
If `True` (default), make copies of the input coordinate arrays.
Can only be passed in as a keyword argument.
{footer}
"""
_components = """
*args, **kwargs
Coordinate components, with names that depend on the subclass.
"""
@format_doc(base_doc, components=_components, footer="")
class BaseCoordinateFrame(ShapedLikeNDArray, metaclass=FrameMeta):
"""
The base class for coordinate frames.
This class is intended to be subclassed to create instances of specific
systems. Subclasses can implement the following attributes:
* `default_representation`
A subclass of `~astropy.coordinates.BaseRepresentation` that will be
treated as the default representation of this frame. This is the
representation assumed by default when the frame is created.
* `default_differential`
A subclass of `~astropy.coordinates.BaseDifferential` that will be
treated as the default differential class of this frame. This is the
differential class assumed by default when the frame is created.
* `~astropy.coordinates.Attribute` class attributes
Frame attributes such as ``FK4.equinox`` or ``FK4.obstime`` are defined
using a descriptor class. See the narrative documentation or
built-in classes code for details.
* `frame_specific_representation_info`
A dictionary mapping the name or class of a representation to a list of
`~astropy.coordinates.RepresentationMapping` objects that tell what
names and default units should be used on this frame for the components
of that representation.
Unless overridden via `frame_specific_representation_info`, velocity name
defaults are:
* ``pm_{lon}_cos{lat}``, ``pm_{lat}`` for `SphericalCosLatDifferential`
proper motion components
* ``pm_{lon}``, ``pm_{lat}`` for `SphericalDifferential` proper motion
components
* ``radial_velocity`` for any ``d_distance`` component
* ``v_{x,y,z}`` for `CartesianDifferential` velocity components
where ``{lon}`` and ``{lat}`` are the frame names of the angular components.
"""
default_representation = None
default_differential = None
# Specifies special names and units for representation and differential
# attributes.
frame_specific_representation_info = {}
_inherit_descriptors_ = (Attribute,)
frame_attributes = OrderedDict()
# Default empty frame_attributes dict
def __init__(self, *args, copy=True, representation_type=None,
differential_type=None, **kwargs):
self._attr_names_with_defaults = []
# This is here for backwards compatibility. It should be possible
# to use either the kwarg representation_type, or representation.
# TODO: In future versions, we will raise a deprecation warning here:
if representation_type is not None:
kwargs['representation_type'] = representation_type
_normalize_representation_type(kwargs)
representation_type = kwargs.pop('representation_type', representation_type)
if representation_type is not None or differential_type is not None:
if representation_type is None:
representation_type = self.default_representation
if (inspect.isclass(differential_type) and
issubclass(differential_type, r.BaseDifferential)):
# TODO: assumes the differential class is for the velocity
# differential
differential_type = {'s': differential_type}
elif isinstance(differential_type, str):
# TODO: assumes the differential class is for the velocity
# differential
diff_cls = r.DIFFERENTIAL_CLASSES[differential_type]
differential_type = {'s': diff_cls}
elif differential_type is None:
if representation_type == self.default_representation:
differential_type = {'s': self.default_differential}
else:
differential_type = {'s': 'base'} # see set_representation_cls()
self.set_representation_cls(representation_type,
**differential_type)
# if not set below, this is a frame with no data
representation_data = None
differential_data = None
args = list(args) # need to be able to pop them
if (len(args) > 0) and (isinstance(args[0], r.BaseRepresentation) or
args[0] is None):
representation_data = args.pop(0)
if len(args) > 0:
raise TypeError(
'Cannot create a frame with both a representation object '
'and other positional arguments')
if representation_data is not None:
diffs = representation_data.differentials
differential_data = diffs.get('s', None)
if ((differential_data is None and len(diffs) > 0) or
(differential_data is not None and len(diffs) > 1)):
raise ValueError('Multiple differentials are associated '
'with the representation object passed in '
'to the frame initializer. Only a single '
'velocity differential is supported. Got: '
'{0}'.format(diffs))
elif self.representation_type:
representation_cls = self.get_representation_cls()
# Get any representation data passed in to the frame initializer
# using keyword or positional arguments for the component names
repr_kwargs = {}
for nmkw, nmrep in self.representation_component_names.items():
if len(args) > 0:
# first gather up positional args
repr_kwargs[nmrep] = args.pop(0)
elif nmkw in kwargs:
repr_kwargs[nmrep] = kwargs.pop(nmkw)
# special-case the Spherical->UnitSpherical if no `distance`
# TODO: possibly generalize this somehow?
if repr_kwargs:
if repr_kwargs.get('distance', True) is None:
del repr_kwargs['distance']
if (issubclass(representation_cls, r.SphericalRepresentation)
and 'distance' not in repr_kwargs):
representation_cls = representation_cls._unit_representation
try:
representation_data = representation_cls(copy=copy,
**repr_kwargs)
except TypeError as e:
# this except clause is here to make the names of the
# attributes more human-readable. Without this the names
# come from the representation instead of the frame's
# attribute names.
msg = str(e)
names = self.get_representation_component_names()
for frame_name, repr_name in names.items():
msg = msg.replace(repr_name, frame_name)
msg = msg.replace('__init__()',
'{0}()'.format(self.__class__.__name__))
e.args = (msg,)
raise
# Now we handle the Differential data:
# Get any differential data passed in to the frame initializer
# using keyword or positional arguments for the component names
differential_cls = self.get_representation_cls('s')
diff_component_names = self.get_representation_component_names('s')
diff_kwargs = {}
for nmkw, nmrep in diff_component_names.items():
if len(args) > 0:
# first gather up positional args
diff_kwargs[nmrep] = args.pop(0)
elif nmkw in kwargs:
diff_kwargs[nmrep] = kwargs.pop(nmkw)
if diff_kwargs:
if (hasattr(differential_cls, '_unit_differential') and
'd_distance' not in diff_kwargs):
differential_cls = differential_cls._unit_differential
elif len(diff_kwargs) == 1 and 'd_distance' in diff_kwargs:
differential_cls = r.RadialDifferential
try:
differential_data = differential_cls(copy=copy,
**diff_kwargs)
except TypeError as e:
# this except clause is here to make the names of the
# attributes more human-readable. Without this the names
# come from the representation instead of the frame's
# attribute names.
msg = str(e)
names = self.get_representation_component_names('s')
for frame_name, repr_name in names.items():
msg = msg.replace(repr_name, frame_name)
msg = msg.replace('__init__()',
'{0}()'.format(self.__class__.__name__))
e.args = (msg,)
raise
if len(args) > 0:
raise TypeError(
'{0}.__init__ had {1} remaining unhandled arguments'.format(
self.__class__.__name__, len(args)))
if representation_data is None and differential_data is not None:
raise ValueError("Cannot pass in differential component data "
"without positional (representation) data.")
if differential_data:
self._data = representation_data.with_differentials(
{'s': differential_data})
else:
self._data = representation_data # possibly None.
values = {}
for fnm, fdefault in self.get_frame_attr_names().items():
# Read-only frame attributes are defined as FrameAttribue
# descriptors which are not settable, so set 'real' attributes as
# the name prefaced with an underscore.
if fnm in kwargs:
value = kwargs.pop(fnm)
setattr(self, '_' + fnm, value)
# Validate attribute by getting it. If the instance has data,
# this also checks its shape is OK. If not, we do it below.
values[fnm] = getattr(self, fnm)
else:
setattr(self, '_' + fnm, fdefault)
self._attr_names_with_defaults.append(fnm)
if kwargs:
raise TypeError(
'Coordinate frame got unexpected keywords: {0}'.format(
list(kwargs)))
# We do ``is None`` because self._data might evaluate to false for
# empty arrays or data == 0
if self._data is None:
# No data: we still need to check that any non-scalar attributes
# have consistent shapes. Collect them for all attributes with
# size > 1 (which should be array-like and thus have a shape).
shapes = {fnm: value.shape for fnm, value in values.items()
if getattr(value, 'size', 1) > 1}
if shapes:
if len(shapes) > 1:
try:
self._no_data_shape = check_broadcast(*shapes.values())
except ValueError:
raise ValueError(
"non-scalar attributes with inconsistent "
"shapes: {0}".format(shapes))
# Above, we checked that it is possible to broadcast all
# shapes. By getting and thus validating the attributes,
# we verify that the attributes can in fact be broadcast.
for fnm in shapes:
getattr(self, fnm)
else:
self._no_data_shape = shapes.popitem()[1]
else:
self._no_data_shape = ()
else:
# This makes the cache keys backwards-compatible, but also adds
# support for having differentials attached to the frame data
# representation object.
if 's' in self._data.differentials:
# TODO: assumes a velocity unit differential
key = (self._data.__class__.__name__,
self._data.differentials['s'].__class__.__name__,
False)
else:
key = (self._data.__class__.__name__, False)
# Set up representation cache.
self.cache['representation'][key] = self._data
@lazyproperty
def cache(self):
"""
Cache for this frame, a dict. It stores anything that should be
computed from the coordinate data (*not* from the frame attributes).
This can be used in functions to store anything that might be
expensive to compute but might be re-used by some other function.
E.g.::
if 'user_data' in myframe.cache:
data = myframe.cache['user_data']
else:
myframe.cache['user_data'] = data = expensive_func(myframe.lat)
If in-place modifications are made to the frame data, the cache should
be cleared::
myframe.cache.clear()
"""
return defaultdict(dict)
@property
def data(self):
"""
The coordinate data for this object. If this frame has no data, an
`ValueError` will be raised. Use `has_data` to
check if data is present on this frame object.
"""
if self._data is None:
raise ValueError('The frame object "{0!r}" does not have '
'associated data'.format(self))
return self._data
@property
def has_data(self):
"""
True if this frame has `data`, False otherwise.
"""
return self._data is not None
@property
def shape(self):
return self.data.shape if self.has_data else self._no_data_shape
# We have to override the ShapedLikeNDArray definitions, since our shape
# does not have to be that of the data.
def __len__(self):
return len(self.data)
def __bool__(self):
return self.has_data and self.size > 0
@property
def size(self):
return self.data.size
@property
def isscalar(self):
return self.has_data and self.data.isscalar
@classmethod
def get_frame_attr_names(cls):
return OrderedDict((name, getattr(cls, name))
for name in cls.frame_attributes)
def get_representation_cls(self, which='base'):
"""The class used for part of this frame's data.
Parameters
----------
which : ('base', 's', `None`)
The class of which part to return. 'base' means the class used to
represent the coordinates; 's' the first derivative to time, i.e.,
the class representing the proper motion and/or radial velocity.
If `None`, return a dict with both.
Returns
-------
representation : `~astropy.coordinates.BaseRepresentation` or `~astropy.coordinates.BaseDifferential`.
"""
if not hasattr(self, '_representation'):
self._representation = {'base': self.default_representation,
's': self.default_differential}
if which is not None:
return self._representation[which]
else:
return self._representation
def set_representation_cls(self, base=None, s='base'):
"""Set representation and/or differential class for this frame's data.
Parameters
----------
base : str, `~astropy.coordinates.BaseRepresentation` subclass, optional
The name or subclass to use to represent the coordinate data.
s : `~astropy.coordinates.BaseDifferential` subclass, optional
The differential subclass to use to represent any velocities,
such as proper motion and radial velocity. If equal to 'base',
which is the default, it will be inferred from the representation.
If `None`, the representation will drop any differentials.
"""
if base is None:
base = self._representation['base']
self._representation = _get_repr_classes(base=base, s=s)
representation_type = property(
fget=get_representation_cls, fset=set_representation_cls,
doc="""The representation class used for this frame's data.
This will be a subclass from `~astropy.coordinates.BaseRepresentation`.
Can also be *set* using the string name of the representation. If you
wish to set an explicit differential class (rather than have it be
inferred), use the ``set_represenation_cls`` method.
""")
@property
def differential_type(self):
"""
The differential used for this frame's data.
This will be a subclass from `~astropy.coordinates.BaseDifferential`.
For simultaneous setting of representation and differentials, see the
``set_represenation_cls`` method.
"""
return self.get_representation_cls('s')
@differential_type.setter
def differential_type(self, value):
self.set_representation_cls(s=value)
# TODO: deprecate these?
@property
def representation(self):
return self.representation_type
@representation.setter
def representation(self, value):
self.representation_type = value
@classmethod
def _get_representation_info(cls):
# This exists as a class method only to support handling frame inputs
# without units, which are deprecated and will be removed. This can be
# moved into the representation_info property at that time.
repr_attrs = {}
for repr_diff_cls in (list(r.REPRESENTATION_CLASSES.values()) +
list(r.DIFFERENTIAL_CLASSES.values())):
repr_attrs[repr_diff_cls] = {'names': [], 'units': []}
for c, c_cls in repr_diff_cls.attr_classes.items():
repr_attrs[repr_diff_cls]['names'].append(c)
# TODO: when "recommended_units" is removed, just directly use
# the default part here.
rec_unit = repr_diff_cls._recommended_units.get(
c, u.deg if issubclass(c_cls, Angle) else None)
repr_attrs[repr_diff_cls]['units'].append(rec_unit)
for repr_diff_cls, mappings in cls._frame_specific_representation_info.items():
# take the 'names' and 'units' tuples from repr_attrs,
# and then use the RepresentationMapping objects
# to update as needed for this frame.
nms = repr_attrs[repr_diff_cls]['names']
uns = repr_attrs[repr_diff_cls]['units']
comptomap = dict([(m.reprname, m) for m in mappings])
for i, c in enumerate(repr_diff_cls.attr_classes.keys()):
if c in comptomap:
mapp = comptomap[c]
nms[i] = mapp.framename
# need the isinstance because otherwise if it's a unit it
# will try to compare to the unit string representation
if not (isinstance(mapp.defaultunit, str) and
mapp.defaultunit == 'recommended'):
uns[i] = mapp.defaultunit
# else we just leave it as recommended_units says above
# Convert to tuples so that this can't mess with frame internals
repr_attrs[repr_diff_cls]['names'] = tuple(nms)
repr_attrs[repr_diff_cls]['units'] = tuple(uns)
return repr_attrs
@property
def representation_info(self):
"""
A dictionary with the information of what attribute names for this frame
apply to particular representations.
"""
return self._get_representation_info()
def get_representation_component_names(self, which='base'):
out = OrderedDict()
repr_or_diff_cls = self.get_representation_cls(which)
if repr_or_diff_cls is None:
return out
data_names = repr_or_diff_cls.attr_classes.keys()
repr_names = self.representation_info[repr_or_diff_cls]['names']
for repr_name, data_name in zip(repr_names, data_names):
out[repr_name] = data_name
return out
def get_representation_component_units(self, which='base'):
out = OrderedDict()
repr_or_diff_cls = self.get_representation_cls(which)
if repr_or_diff_cls is None:
return out
repr_attrs = self.representation_info[repr_or_diff_cls]
repr_names = repr_attrs['names']
repr_units = repr_attrs['units']
for repr_name, repr_unit in zip(repr_names, repr_units):
if repr_unit:
out[repr_name] = repr_unit
return out
representation_component_names = property(get_representation_component_names)
representation_component_units = property(get_representation_component_units)
def _replicate(self, data, copy=False, **kwargs):
"""Base for replicating a frame, with possibly different attributes.
Produces a new instance of the frame using the attributes of the old
frame (unless overridden) and with the data given.
Parameters
----------
data : `~astropy.coordinates.BaseRepresentation` or `None`
Data to use in the new frame instance. If `None`, it will be
a data-less frame.
copy : bool, optional
Whether data and the attributes on the old frame should be copied
(default), or passed on by reference.
**kwargs
Any attributes that should be overridden.
"""
# This is to provide a slightly nicer error message if the user tries
# to use frame_obj.representation instead of frame_obj.data to get the
# underlying representation object [e.g., #2890]
if inspect.isclass(data):
raise TypeError('Class passed as data instead of a representation '
'instance. If you called frame.representation, this'
' returns the representation class. frame.data '
'returns the instantiated object - you may want to '
' use this instead.')
if copy and data is not None:
data = data.copy()
for attr in self.get_frame_attr_names():
if (attr not in self._attr_names_with_defaults and
attr not in kwargs):
value = getattr(self, attr)
if copy:
value = value.copy()
kwargs[attr] = value
return self.__class__(data, copy=False, **kwargs)
def replicate(self, copy=False, **kwargs):
"""
Return a replica of the frame, optionally with new frame attributes.
The replica is a new frame object that has the same data as this frame
object and with frame attributes overriden if they are provided as extra
keyword arguments to this method. If ``copy`` is set to `True` then a
copy of the internal arrays will be made. Otherwise the replica will
use a reference to the original arrays when possible to save memory. The
internal arrays are normally not changeable by the user so in most cases
it should not be necessary to set ``copy`` to `True`.
Parameters
----------
copy : bool, optional
If True, the resulting object is a copy of the data. When False,
references are used where possible. This rule also applies to the
frame attributes.
Any additional keywords are treated as frame attributes to be set on the
new frame object.
Returns
-------
frameobj : same as this frame
Replica of this object, but possibly with new frame attributes.
"""
return self._replicate(self.data, copy=copy, **kwargs)
def replicate_without_data(self, copy=False, **kwargs):
"""
Return a replica without data, optionally with new frame attributes.
The replica is a new frame object without data but with the same frame
attributes as this object, except where overriden by extra keyword
arguments to this method. The ``copy`` keyword determines if the frame
attributes are truly copied vs being references (which saves memory for
cases where frame attributes are large).
This method is essentially the converse of `realize_frame`.
Parameters
----------
copy : bool, optional
If True, the resulting object has copies of the frame attributes.
When False, references are used where possible.
Any additional keywords are treated as frame attributes to be set on the
new frame object.
Returns
-------
frameobj : same as this frame
Replica of this object, but without data and possibly with new frame
attributes.
"""
return self._replicate(None, copy=copy, **kwargs)
def realize_frame(self, representation_type):
"""
Generates a new frame *with new data* from another frame (which may or
may not have data). Roughly speaking, the converse of
`replicate_without_data`.
Parameters
----------
representation_type : `BaseRepresentation`
The representation to use as the data for the new frame.
Returns
-------
frameobj : same as this frame
A new object with the same frame attributes as this one, but
with the ``representation`` as the data.
"""
return self._replicate(representation_type)
def represent_as(self, base, s='base', in_frame_units=False):
"""
Generate and return a new representation of this frame's `data`
as a Representation object.
Note: In order to make an in-place change of the representation
of a Frame or SkyCoord object, set the ``representation``
attribute of that object to the desired new representation, or
use the ``set_representation_cls`` method to also set the differential.
Parameters
----------
base : subclass of BaseRepresentation or string
The type of representation to generate. Must be a *class*
(not an instance), or the string name of the representation
class.
s : subclass of `~astropy.coordinates.BaseDifferential`, str, optional
Class in which any velocities should be represented. Must be
a *class* (not an instance), or the string name of the
differential class. If equal to 'base' (default), inferred from
the base class. If `None`, all velocity information is dropped.
in_frame_units : bool, keyword only
Force the representation units to match the specified units
particular to this frame
Returns
-------
newrep : BaseRepresentation-derived object
A new representation object of this frame's `data`.
Raises
------
AttributeError
If this object had no `data`
Examples
--------
>>> from astropy import units as u
>>> from astropy.coordinates import SkyCoord, CartesianRepresentation
>>> coord = SkyCoord(0*u.deg, 0*u.deg)
>>> coord.represent_as(CartesianRepresentation) # doctest: +FLOAT_CMP
<CartesianRepresentation (x, y, z) [dimensionless]
(1., 0., 0.)>
>>> coord.representation = CartesianRepresentation
>>> coord # doctest: +FLOAT_CMP
<SkyCoord (ICRS): (x, y, z) [dimensionless]
(1., 0., 0.)>
"""
# For backwards compatibility (because in_frame_units used to be the
# 2nd argument), we check to see if `new_differential` is a boolean. If
# it is, we ignore the value of `new_differential` and warn about the
# position change
if isinstance(s, bool):
warnings.warn("The argument position for `in_frame_units` in "
"`represent_as` has changed. Use as a keyword "
"argument if needed.", AstropyWarning)
in_frame_units = s
s = 'base'
# In the future, we may want to support more differentials, in which
# case one probably needs to define **kwargs above and use it here.
# But for now, we only care about the velocity.
repr_classes = _get_repr_classes(base=base, s=s)
representation_cls = repr_classes['base']
# We only keep velocity information
if 's' in self.data.differentials:
differential_cls = repr_classes['s']
elif s is None or s == 'base':
differential_cls = None
else:
raise TypeError('Frame data has no associated differentials '
'(i.e. the frame has no velocity data) - '
'represent_as() only accepts a new '
'representation.')
if differential_cls:
cache_key = (representation_cls.__name__,
differential_cls.__name__, in_frame_units)
else:
cache_key = (representation_cls.__name__, in_frame_units)
cached_repr = self.cache['representation'].get(cache_key)
if not cached_repr:
if differential_cls:
# TODO NOTE: only supports a single differential
data = self.data.represent_as(representation_cls,
differential_cls)
diff = data.differentials['s'] # TODO: assumes velocity
else:
data = self.data.represent_as(representation_cls)
# If the new representation is known to this frame and has a defined
# set of names and units, then use that.
new_attrs = self.representation_info.get(representation_cls)
if new_attrs and in_frame_units:
datakwargs = dict((comp, getattr(data, comp))
for comp in data.components)
for comp, new_attr_unit in zip(data.components, new_attrs['units']):
if new_attr_unit:
datakwargs[comp] = datakwargs[comp].to(new_attr_unit)
data = data.__class__(copy=False, **datakwargs)
if differential_cls:
# the original differential
data_diff = self.data.differentials['s']
# If the new differential is known to this frame and has a
# defined set of names and units, then use that.
new_attrs = self.representation_info.get(differential_cls)
if new_attrs and in_frame_units:
diffkwargs = dict((comp, getattr(diff, comp))
for comp in diff.components)
for comp, new_attr_unit in zip(diff.components,
new_attrs['units']):
# Some special-casing to treat a situation where the
# input data has a UnitSphericalDifferential or a
# RadialDifferential. It is re-represented to the
# frame's differential class (which might be, e.g., a
# dimensional Differential), so we don't want to try to
# convert the empty component units
if (isinstance(data_diff,
(r.UnitSphericalDifferential,
r.UnitSphericalCosLatDifferential)) and
comp not in data_diff.__class__.attr_classes):
continue
elif (isinstance(data_diff, r.RadialDifferential) and
comp not in data_diff.__class__.attr_classes):
continue
if new_attr_unit and hasattr(diff, comp):
diffkwargs[comp] = diffkwargs[comp].to(new_attr_unit)
diff = diff.__class__(copy=False, **diffkwargs)
# Here we have to bypass using with_differentials() because
# it has a validation check. But because
# .representation_type and .differential_type don't point to
# the original classes, if the input differential is a
# RadialDifferential, it usually gets turned into a
# SphericalCosLatDifferential (or whatever the default is)
# with strange units for the d_lon and d_lat attributes.
# This then causes the dictionary key check to fail (i.e.
# comparison against `diff._get_deriv_key()`)
data._differentials.update({'s': diff})
self.cache['representation'][cache_key] = data
return self.cache['representation'][cache_key]
def transform_to(self, new_frame):
"""
Transform this object's coordinate data to a new frame.
Parameters
----------
new_frame : class or frame object or SkyCoord object
The frame to transform this coordinate frame into.
Returns
-------
transframe
A new object with the coordinate data represented in the
``newframe`` system.
Raises
------
ValueError
If there is no possible transformation route.
"""
from .errors import ConvertError
if self._data is None:
raise ValueError('Cannot transform a frame with no data')
if (getattr(self.data, 'differentials', None) and
hasattr(self, 'obstime') and hasattr(new_frame, 'obstime') and
np.any(self.obstime != new_frame.obstime)):
raise NotImplementedError('You cannot transform a frame that has '
'velocities to another frame at a '
'different obstime. If you think this '
'should (or should not) be possible, '
'please comment at https://github.com/astropy/astropy/issues/6280')
if inspect.isclass(new_frame):
# Use the default frame attributes for this class
new_frame = new_frame()
if hasattr(new_frame, '_sky_coord_frame'):
# Input new_frame is not a frame instance or class and is most
# likely a SkyCoord object.
new_frame = new_frame._sky_coord_frame
trans = frame_transform_graph.get_transform(self.__class__,
new_frame.__class__)
if trans is None:
if new_frame is self.__class__:
# no special transform needed, but should update frame info
return new_frame.realize_frame(self.data)
msg = 'Cannot transform from {0} to {1}'
raise ConvertError(msg.format(self.__class__, new_frame.__class__))
return trans(self, new_frame)
def is_transformable_to(self, new_frame):
"""
Determines if this coordinate frame can be transformed to another
given frame.
Parameters
----------
new_frame : class or frame object
The proposed frame to transform into.
Returns
-------
transformable : bool or str
`True` if this can be transformed to ``new_frame``, `False` if
not, or the string 'same' if ``new_frame`` is the same system as
this object but no transformation is defined.
Notes
-----
A return value of 'same' means the transformation will work, but it will
just give back a copy of this object. The intended usage is::
if coord.is_transformable_to(some_unknown_frame):
coord2 = coord.transform_to(some_unknown_frame)
This will work even if ``some_unknown_frame`` turns out to be the same
frame class as ``coord``. This is intended for cases where the frame
is the same regardless of the frame attributes (e.g. ICRS), but be
aware that it *might* also indicate that someone forgot to define the
transformation between two objects of the same frame class but with
different attributes.
"""
new_frame_cls = new_frame if inspect.isclass(new_frame) else new_frame.__class__
trans = frame_transform_graph.get_transform(self.__class__, new_frame_cls)
if trans is None:
if new_frame_cls is self.__class__:
return 'same'
else:
return False
else:
return True
def is_frame_attr_default(self, attrnm):
"""
Determine whether or not a frame attribute has its value because it's
the default value, or because this frame was created with that value
explicitly requested.
Parameters
----------
attrnm : str
The name of the attribute to check.
Returns
-------
isdefault : bool
True if the attribute ``attrnm`` has its value by default, False if
it was specified at creation of this frame.
"""
return attrnm in self._attr_names_with_defaults
def is_equivalent_frame(self, other):
"""
Checks if this object is the same frame as the ``other`` object.
To be the same frame, two objects must be the same frame class and have
the same frame attributes. Note that it does *not* matter what, if any,
data either object has.
Parameters
----------
other : BaseCoordinateFrame
the other frame to check
Returns
-------
isequiv : bool
True if the frames are the same, False if not.
Raises
------
TypeError
If ``other`` isn't a `BaseCoordinateFrame` or subclass.
"""
if self.__class__ == other.__class__:
for frame_attr_name in self.get_frame_attr_names():
if np.any(getattr(self, frame_attr_name) !=
getattr(other, frame_attr_name)):
return False
return True
elif not isinstance(other, BaseCoordinateFrame):
raise TypeError("Tried to do is_equivalent_frame on something that "
"isn't a frame")
else:
return False
def __repr__(self):
frameattrs = self._frame_attrs_repr()
data_repr = self._data_repr()
if frameattrs:
frameattrs = ' ({0})'.format(frameattrs)
if data_repr:
return '<{0} Coordinate{1}: {2}>'.format(self.__class__.__name__,
frameattrs, data_repr)
else:
return '<{0} Frame{1}>'.format(self.__class__.__name__,
frameattrs)
def _data_repr(self):
"""Returns a string representation of the coordinate data."""
if not self.has_data:
return ''
if self.representation:
if (issubclass(self.representation, r.SphericalRepresentation) and
isinstance(self.data, r.UnitSphericalRepresentation)):
rep_cls = self.data.__class__
else:
rep_cls = self.representation
if 's' in self.data.differentials:
dif_cls = self.get_representation_cls('s')
dif_data = self.data.differentials['s']
if isinstance(dif_data, (r.UnitSphericalDifferential,
r.UnitSphericalCosLatDifferential,
r.RadialDifferential)):
dif_cls = dif_data.__class__
else:
dif_cls = None
data = self.represent_as(rep_cls, dif_cls, in_frame_units=True)
data_repr = repr(data)
for nmpref, nmrepr in self.representation_component_names.items():
data_repr = data_repr.replace(nmrepr, nmpref)
else:
data = self.data
data_repr = repr(self.data)
if data_repr.startswith('<' + data.__class__.__name__):
# remove both the leading "<" and the space after the name, as well
# as the trailing ">"
data_repr = data_repr[(len(data.__class__.__name__) + 2):-1]
else:
data_repr = 'Data:\n' + data_repr
if 's' in self.data.differentials:
data_repr_spl = data_repr.split('\n')
if 'has differentials' in data_repr_spl[-1]:
diffrepr = repr(data.differentials['s']).split('\n')
if diffrepr[0].startswith('<'):
diffrepr[0] = ' ' + ' '.join(diffrepr[0].split(' ')[1:])
for frm_nm, rep_nm in self.get_representation_component_names('s').items():
diffrepr[0] = diffrepr[0].replace(rep_nm, frm_nm)
if diffrepr[-1].endswith('>'):
diffrepr[-1] = diffrepr[-1][:-1]
data_repr_spl[-1] = '\n'.join(diffrepr)
data_repr = '\n'.join(data_repr_spl)
return data_repr
def _frame_attrs_repr(self):
"""
Returns a string representation of the frame's attributes, if any.
"""
return ', '.join([attrnm + '=' + str(getattr(self, attrnm))
for attrnm in self.get_frame_attr_names()])
def _apply(self, method, *args, **kwargs):
"""Create a new instance, applying a method to the underlying data.
In typical usage, the method is any of the shape-changing methods for
`~numpy.ndarray` (``reshape``, ``swapaxes``, etc.), as well as those
picking particular elements (``__getitem__``, ``take``, etc.), which
are all defined in `~astropy.utils.misc.ShapedLikeNDArray`. It will be
applied to the underlying arrays in the representation (e.g., ``x``,
``y``, and ``z`` for `~astropy.coordinates.CartesianRepresentation`),
as well as to any frame attributes that have a shape, with the results
used to create a new instance.
Internally, it is also used to apply functions to the above parts
(in particular, `~numpy.broadcast_to`).
Parameters
----------
method : str or callable
If str, it is the name of a method that is applied to the internal
``components``. If callable, the function is applied.
args : tuple
Any positional arguments for ``method``.
kwargs : dict
Any keyword arguments for ``method``.
"""
def apply_method(value):
if isinstance(value, ShapedLikeNDArray):
return value._apply(method, *args, **kwargs)
else:
if callable(method):
return method(value, *args, **kwargs)
else:
return getattr(value, method)(*args, **kwargs)
new = super().__new__(self.__class__)
if hasattr(self, '_representation'):
new._representation = self._representation.copy()
new._attr_names_with_defaults = self._attr_names_with_defaults.copy()
for attr in self.frame_attributes:
_attr = '_' + attr
if attr in self._attr_names_with_defaults:
setattr(new, _attr, getattr(self, _attr))
else:
value = getattr(self, _attr)
if getattr(value, 'size', 1) > 1:
value = apply_method(value)
elif method == 'copy' or method == 'flatten':
# flatten should copy also for a single element array, but
# we cannot use it directly for array scalars, since it
# always returns a one-dimensional array. So, just copy.
value = copy.copy(value)
setattr(new, _attr, value)
if self.has_data:
new._data = apply_method(self.data)
else:
new._data = None
shapes = [getattr(new, '_' + attr).shape
for attr in new.frame_attributes
if (attr not in new._attr_names_with_defaults and
getattr(getattr(new, '_' + attr), 'size', 1) > 1)]
if shapes:
new._no_data_shape = (check_broadcast(*shapes)
if len(shapes) > 1 else shapes[0])
else:
new._no_data_shape = ()
return new
@override__dir__
def __dir__(self):
"""
Override the builtin `dir` behavior to include representation
names.
TODO: dynamic representation transforms (i.e. include cylindrical et al.).
"""
dir_values = set(self.representation_component_names)
dir_values |= set(self.get_representation_component_names('s'))
return dir_values
def __getattr__(self, attr):
"""
Allow access to attributes on the representation and differential as
found via ``self.get_representation_component_names``.
TODO: We should handle dynamic representation transforms here (e.g.,
`.cylindrical`) instead of defining properties as below.
"""
# attr == '_representation' is likely from the hasattr() test in the
# representation property which is used for
# self.representation_component_names.
#
# Prevent infinite recursion here.
if attr.startswith('_'):
return self.__getattribute__(attr) # Raise AttributeError.
repr_names = self.representation_component_names
if attr in repr_names:
if self._data is None:
self.data # this raises the "no data" error by design - doing it
# this way means we don't have to replicate the error message here
rep = self.represent_as(self.representation_type,
in_frame_units=True)
val = getattr(rep, repr_names[attr])
return val
diff_names = self.get_representation_component_names('s')
if attr in diff_names:
if self._data is None:
self.data # see above.
# TODO: this doesn't work for the case when there is only
# unitspherical information. The differential_type gets set to the
# default_differential, which expects full information, so the
# units don't work out
rep = self.represent_as(in_frame_units=True,
**self.get_representation_cls(None))
val = getattr(rep.differentials['s'], diff_names[attr])
return val
return self.__getattribute__(attr) # Raise AttributeError.
def __setattr__(self, attr, value):
# Don't slow down access of private attributes!
if not attr.startswith('_'):
if hasattr(self, 'representation_info'):
repr_attr_names = set()
for representation_attr in self.representation_info.values():
repr_attr_names.update(representation_attr['names'])
if attr in repr_attr_names:
raise AttributeError(
'Cannot set any frame attribute {0}'.format(attr))
super().__setattr__(attr, value)
def separation(self, other):
"""
Computes on-sky separation between this coordinate and another.
.. note::
If the ``other`` coordinate object is in a different frame, it is
first transformed to the frame of this object. This can lead to
unintutive behavior if not accounted for. Particularly of note is
that ``self.separation(other)`` and ``other.separation(self)`` may
not give the same answer in this case.
Parameters
----------
other : `~astropy.coordinates.BaseCoordinateFrame`
The coordinate to get the separation to.
Returns
-------
sep : `~astropy.coordinates.Angle`
The on-sky separation between this and the ``other`` coordinate.
Notes
-----
The separation is calculated using the Vincenty formula, which
is stable at all locations, including poles and antipodes [1]_.
.. [1] https://en.wikipedia.org/wiki/Great-circle_distance
"""
from .angle_utilities import angular_separation
from .angles import Angle
self_unit_sph = self.represent_as(r.UnitSphericalRepresentation)
other_transformed = other.transform_to(self)
other_unit_sph = other_transformed.represent_as(r.UnitSphericalRepresentation)
# Get the separation as a Quantity, convert to Angle in degrees
sep = angular_separation(self_unit_sph.lon, self_unit_sph.lat,
other_unit_sph.lon, other_unit_sph.lat)
return Angle(sep, unit=u.degree)
def separation_3d(self, other):
"""
Computes three dimensional separation between this coordinate
and another.
Parameters
----------
other : `~astropy.coordinates.BaseCoordinateFrame`
The coordinate system to get the distance to.
Returns
-------
sep : `~astropy.coordinates.Distance`
The real-space distance between these two coordinates.
Raises
------
ValueError
If this or the other coordinate do not have distances.
"""
from .distances import Distance
if issubclass(self.data.__class__, r.UnitSphericalRepresentation):
raise ValueError('This object does not have a distance; cannot '
'compute 3d separation.')
# do this first just in case the conversion somehow creates a distance
other_in_self_system = other.transform_to(self)
if issubclass(other_in_self_system.__class__, r.UnitSphericalRepresentation):
raise ValueError('The other object does not have a distance; '
'cannot compute 3d separation.')
# drop the differentials to ensure they don't do anything odd in the
# subtraction
self_car = self.data.without_differentials().represent_as(r.CartesianRepresentation)
other_car = other_in_self_system.data.without_differentials().represent_as(r.CartesianRepresentation)
return Distance((self_car - other_car).norm())
@property
def cartesian(self):
"""
Shorthand for a cartesian representation of the coordinates in this
object.
"""
# TODO: if representations are updated to use a full transform graph,
# the representation aliases should not be hard-coded like this
return self.represent_as('cartesian', in_frame_units=True)
@property
def spherical(self):
"""
Shorthand for a spherical representation of the coordinates in this
object.
"""
# TODO: if representations are updated to use a full transform graph,
# the representation aliases should not be hard-coded like this
return self.represent_as('spherical', in_frame_units=True)
@property
def sphericalcoslat(self):
"""
Shorthand for a spherical representation of the positional data and a
`SphericalCosLatDifferential` for the velocity data in this object.
"""
# TODO: if representations are updated to use a full transform graph,
# the representation aliases should not be hard-coded like this
return self.represent_as('spherical', 'sphericalcoslat',
in_frame_units=True)
@property
def velocity(self):
"""
Shorthand for retrieving the Cartesian space-motion as a
`CartesianDifferential` object. This is equivalent to calling
``self.cartesian.differentials['s']``.
"""
if 's' not in self.data.differentials:
raise ValueError('Frame has no associated velocity (Differential) '
'data information.')
try:
v = self.cartesian.differentials['s']
except Exception as e:
raise ValueError('Could not retrieve a Cartesian velocity. Your '
'frame must include velocity information for this '
'to work.')
return v
@property
def proper_motion(self):
"""
Shorthand for the two-dimensional proper motion as a
`~astropy.units.Quantity` object with angular velocity units. In the
returned `~astropy.units.Quantity`, ``axis=0`` is the longitude/latitude
dimension so that ``.proper_motion[0]`` is the longitudinal proper
motion and ``.proper_motion[1]`` is latitudinal. The longitudinal proper
motion already includes the cos(latitude) term.
"""
if 's' not in self.data.differentials:
raise ValueError('Frame has no associated velocity (Differential) '
'data information.')
sph = self.represent_as('spherical', 'sphericalcoslat',
in_frame_units=True)
pm_lon = sph.differentials['s'].d_lon_coslat
pm_lat = sph.differentials['s'].d_lat
return np.stack((pm_lon.value,
pm_lat.to(pm_lon.unit).value), axis=0) * pm_lon.unit
@property
def radial_velocity(self):
"""
Shorthand for the radial or line-of-sight velocity as a
`~astropy.units.Quantity` object.
"""
if 's' not in self.data.differentials:
raise ValueError('Frame has no associated velocity (Differential) '
'data information.')
sph = self.represent_as('spherical', in_frame_units=True)
return sph.differentials['s'].d_distance
class GenericFrame(BaseCoordinateFrame):
"""
A frame object that can't store data but can hold any arbitrary frame
attributes. Mostly useful as a utility for the high-level class to store
intermediate frame attributes.
Parameters
----------
frame_attrs : dict
A dictionary of attributes to be used as the frame attributes for this
frame.
"""
name = None # it's not a "real" frame so it doesn't have a name
def __init__(self, frame_attrs):
self.frame_attributes = OrderedDict()
for name, default in frame_attrs.items():
self.frame_attributes[name] = Attribute(default)
setattr(self, '_' + name, default)
super().__init__(None)
def __getattr__(self, name):
if '_' + name in self.__dict__:
return getattr(self, '_' + name)
else:
raise AttributeError('no {0}'.format(name))
def __setattr__(self, name, value):
if name in self.get_frame_attr_names():
raise AttributeError("can't set frame attribute '{0}'".format(name))
else:
super().__setattr__(name, value)
|
3dfd36d3b798b8196bea52e498dc572042160f5394b27bfad9f0a199f3f9fad7 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module contains convenience functions implementing some of the
algorithms contained within Jean Meeus, 'Astronomical Algorithms',
second edition, 1998, Willmann-Bell.
"""
import numpy as np
from numpy.polynomial.polynomial import polyval
from .. import units as u
from .. import _erfa as erfa
from . import ICRS, SkyCoord, GeocentricTrueEcliptic
from .builtin_frames.utils import get_jd12
__all__ = ["calc_moon"]
# Meeus 1998: table 47.A
# D M M' F l r
_MOON_L_R = (
(0, 0, 1, 0, 6288774, -20905355),
(2, 0, -1, 0, 1274027, -3699111),
(2, 0, 0, 0, 658314, -2955968),
(0, 0, 2, 0, 213618, -569925),
(0, 1, 0, 0, -185116, 48888),
(0, 0, 0, 2, -114332, -3149),
(2, 0, -2, 0, 58793, 246158),
(2, -1, -1, 0, 57066, -152138),
(2, 0, 1, 0, 53322, -170733),
(2, -1, 0, 0, 45758, -204586),
(0, 1, -1, 0, -40923, -129620),
(1, 0, 0, 0, -34720, 108743),
(0, 1, 1, 0, -30383, 104755),
(2, 0, 0, -2, 15327, 10321),
(0, 0, 1, 2, -12528, 0),
(0, 0, 1, -2, 10980, 79661),
(4, 0, -1, 0, 10675, -34782),
(0, 0, 3, 0, 10034, -23210),
(4, 0, -2, 0, 8548, -21636),
(2, 1, -1, 0, -7888, 24208),
(2, 1, 0, 0, -6766, 30824),
(1, 0, -1, 0, -5163, -8379),
(1, 1, 0, 0, 4987, -16675),
(2, -1, 1, 0, 4036, -12831),
(2, 0, 2, 0, 3994, -10445),
(4, 0, 0, 0, 3861, -11650),
(2, 0, -3, 0, 3665, 14403),
(0, 1, -2, 0, -2689, -7003),
(2, 0, -1, 2, -2602, 0),
(2, -1, -2, 0, 2390, 10056),
(1, 0, 1, 0, -2348, 6322),
(2, -2, 0, 0, 2236, -9884),
(0, 1, 2, 0, -2120, 5751),
(0, 2, 0, 0, -2069, 0),
(2, -2, -1, 0, 2048, -4950),
(2, 0, 1, -2, -1773, 4130),
(2, 0, 0, 2, -1595, 0),
(4, -1, -1, 0, 1215, -3958),
(0, 0, 2, 2, -1110, 0),
(3, 0, -1, 0, -892, 3258),
(2, 1, 1, 0, -810, 2616),
(4, -1, -2, 0, 759, -1897),
(0, 2, -1, 0, -713, -2117),
(2, 2, -1, 0, -700, 2354),
(2, 1, -2, 0, 691, 0),
(2, -1, 0, -2, 596, 0),
(4, 0, 1, 0, 549, -1423),
(0, 0, 4, 0, 537, -1117),
(4, -1, 0, 0, 520, -1571),
(1, 0, -2, 0, -487, -1739),
(2, 1, 0, -2, -399, 0),
(0, 0, 2, -2, -381, -4421),
(1, 1, 1, 0, 351, 0),
(3, 0, -2, 0, -340, 0),
(4, 0, -3, 0, 330, 0),
(2, -1, 2, 0, 327, 0),
(0, 2, 1, 0, -323, 1165),
(1, 1, -1, 0, 299, 0),
(2, 0, 3, 0, 294, 0),
(2, 0, -1, -2, 0, 8752)
)
# Meeus 1998: table 47.B
# D M M' F b
_MOON_B = (
(0, 0, 0, 1, 5128122),
(0, 0, 1, 1, 280602),
(0, 0, 1, -1, 277693),
(2, 0, 0, -1, 173237),
(2, 0, -1, 1, 55413),
(2, 0, -1, -1, 46271),
(2, 0, 0, 1, 32573),
(0, 0, 2, 1, 17198),
(2, 0, 1, -1, 9266),
(0, 0, 2, -1, 8822),
(2, -1, 0, -1, 8216),
(2, 0, -2, -1, 4324),
(2, 0, 1, 1, 4200),
(2, 1, 0, -1, -3359),
(2, -1, -1, 1, 2463),
(2, -1, 0, 1, 2211),
(2, -1, -1, -1, 2065),
(0, 1, -1, -1, -1870),
(4, 0, -1, -1, 1828),
(0, 1, 0, 1, -1794),
(0, 0, 0, 3, -1749),
(0, 1, -1, 1, -1565),
(1, 0, 0, 1, -1491),
(0, 1, 1, 1, -1475),
(0, 1, 1, -1, -1410),
(0, 1, 0, -1, -1344),
(1, 0, 0, -1, -1335),
(0, 0, 3, 1, 1107),
(4, 0, 0, -1, 1021),
(4, 0, -1, 1, 833),
# second column
(0, 0, 1, -3, 777),
(4, 0, -2, 1, 671),
(2, 0, 0, -3, 607),
(2, 0, 2, -1, 596),
(2, -1, 1, -1, 491),
(2, 0, -2, 1, -451),
(0, 0, 3, -1, 439),
(2, 0, 2, 1, 422),
(2, 0, -3, -1, 421),
(2, 1, -1, 1, -366),
(2, 1, 0, 1, -351),
(4, 0, 0, 1, 331),
(2, -1, 1, 1, 315),
(2, -2, 0, -1, 302),
(0, 0, 1, 3, -283),
(2, 1, 1, -1, -229),
(1, 1, 0, -1, 223),
(1, 1, 0, 1, 223),
(0, 1, -2, -1, -220),
(2, 1, -1, -1, -220),
(1, 0, 1, 1, -185),
(2, -1, -2, -1, 181),
(0, 1, 2, 1, -177),
(4, 0, -2, -1, 176),
(4, -1, -1, -1, 166),
(1, 0, 1, -1, -164),
(4, 0, 1, -1, 132),
(1, 0, -1, -1, -119),
(4, -1, 0, -1, 115),
(2, -2, 0, 1, 107)
)
"""
Coefficients of polynomials for various terms:
Lc : Mean longitude of Moon, w.r.t mean Equinox of date
D : Mean elongation of the Moon
M: Sun's mean anomaly
Mc : Moon's mean anomaly
F : Moon's argument of latitude (mean distance of Moon from its ascending node).
"""
_coLc = (2.18316448e+02, 4.81267881e+05, -1.57860000e-03,
1.85583502e-06, -1.53388349e-08)
_coD = (2.97850192e+02, 4.45267111e+05, -1.88190000e-03,
1.83194472e-06, -8.84447000e-09)
_coM = (3.57529109e+02, 3.59990503e+04, -1.53600000e-04,
4.08329931e-08)
_coMc = (1.34963396e+02, 4.77198868e+05, 8.74140000e-03,
1.43474081e-05, -6.79717238e-08)
_coF = (9.32720950e+01, 4.83202018e+05, -3.65390000e-03,
-2.83607487e-07, 1.15833246e-09)
_coA1 = (119.75, 131.849)
_coA2 = (53.09, 479264.290)
_coA3 = (313.45, 481266.484)
_coE = (1.0, -0.002516, -0.0000074)
def calc_moon(t):
"""
Lunar position model ELP2000-82 of (Chapront-Touze' and Chapront, 1983, 124, 50)
This is the simplified version of Jean Meeus, Astronomical Algorithms,
second edition, 1998, Willmann-Bell. Meeus claims approximate accuracy of 10"
in longitude and 4" in latitude, with no specified time range.
Tests against JPL ephemerides show accuracy of 10 arcseconds and 50 km over the
date range CE 1950-2050.
Parameters
-----------
t : `~astropy.time.Time`
Time of observation.
Returns
--------
skycoord : `~astropy.coordinates.SkyCoord`
ICRS Coordinate for the body
"""
# number of centuries since J2000.0.
# This should strictly speaking be in Ephemeris Time, but TDB or TT
# will introduce error smaller than intrinsic accuracy of algorithm.
T = (t.tdb.jyear-2000.0)/100.
# constants that are needed for all calculations
Lc = u.Quantity(polyval(T, _coLc), u.deg)
D = u.Quantity(polyval(T, _coD), u.deg)
M = u.Quantity(polyval(T, _coM), u.deg)
Mc = u.Quantity(polyval(T, _coMc), u.deg)
F = u.Quantity(polyval(T, _coF), u.deg)
A1 = u.Quantity(polyval(T, _coA1), u.deg)
A2 = u.Quantity(polyval(T, _coA2), u.deg)
A3 = u.Quantity(polyval(T, _coA3), u.deg)
E = polyval(T, _coE)
suml = sumr = 0.0
for DNum, MNum, McNum, FNum, LFac, RFac in _MOON_L_R:
corr = E ** abs(MNum)
suml += LFac*corr*np.sin(D*DNum+M*MNum+Mc*McNum+F*FNum)
sumr += RFac*corr*np.cos(D*DNum+M*MNum+Mc*McNum+F*FNum)
sumb = 0.0
for DNum, MNum, McNum, FNum, BFac in _MOON_B:
corr = E ** abs(MNum)
sumb += BFac*corr*np.sin(D*DNum+M*MNum+Mc*McNum+F*FNum)
suml += (3958*np.sin(A1) + 1962*np.sin(Lc-F) + 318*np.sin(A2))
sumb += (-2235*np.sin(Lc) + 382*np.sin(A3) + 175*np.sin(A1-F) +
175*np.sin(A1+F) + 127*np.sin(Lc-Mc) - 115*np.sin(Lc+Mc))
# ensure units
suml = suml*u.microdegree
sumb = sumb*u.microdegree
# nutation of longitude
jd1, jd2 = get_jd12(t, 'tt')
nut, _ = erfa.nut06a(jd1, jd2)
nut = nut*u.rad
# calculate ecliptic coordinates
lon = Lc + suml + nut
lat = sumb
dist = (385000.56+sumr/1000)*u.km
# Meeus algorithm gives GeocentricTrueEcliptic coordinates
ecliptic_coo = GeocentricTrueEcliptic(lon, lat, distance=dist,
equinox=t)
return SkyCoord(ecliptic_coo.transform_to(ICRS))
|
7ee98ad08bbf2679c3662425250d601b7c56b343d8b91a44d09e04d1f6fa0229 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
from warnings import warn
import collections
import socket
import json
import urllib.request
import urllib.error
import urllib.parse
import numpy as np
from .. import units as u
from .. import constants as consts
from ..units.quantity import QuantityInfoBase
from ..utils.exceptions import AstropyUserWarning
from ..utils.compat.numpycompat import NUMPY_LT_1_12
from .angles import Longitude, Latitude
from .representation import CartesianRepresentation, CartesianDifferential
from .errors import UnknownSiteException
from ..utils import data, deprecated
try:
# Not guaranteed available at setup time.
from .. import _erfa as erfa
except ImportError:
if not _ASTROPY_SETUP_:
raise
__all__ = ['EarthLocation']
GeodeticLocation = collections.namedtuple('GeodeticLocation', ['lon', 'lat', 'height'])
# Available ellipsoids (defined in erfam.h, with numbers exposed in erfa).
ELLIPSOIDS = ('WGS84', 'GRS80', 'WGS72')
OMEGA_EARTH = u.Quantity(7.292115855306589e-5, 1./u.s)
"""
Rotational velocity of Earth. In UT1 seconds, this would be 2 pi / (24 * 3600),
but we need the value in SI seconds.
See Explanatory Supplement to the Astronomical Almanac, ed. P. Kenneth Seidelmann (1992),
University Science Books.
"""
def _check_ellipsoid(ellipsoid=None, default='WGS84'):
if ellipsoid is None:
ellipsoid = default
if ellipsoid not in ELLIPSOIDS:
raise ValueError('Ellipsoid {0} not among known ones ({1})'
.format(ellipsoid, ELLIPSOIDS))
return ellipsoid
def _get_json_result(url, err_str):
# need to do this here to prevent a series of complicated circular imports
from .name_resolve import NameResolveError
try:
# Retrieve JSON response from Google maps API
resp = urllib.request.urlopen(url, timeout=data.conf.remote_timeout)
resp_data = json.loads(resp.read().decode('utf8'))
except urllib.error.URLError as e:
# This catches a timeout error, see:
# http://stackoverflow.com/questions/2712524/handling-urllib2s-timeout-python
if isinstance(e.reason, socket.timeout):
raise NameResolveError(err_str.format(msg="connection timed out"))
else:
raise NameResolveError(err_str.format(msg=e.reason))
except socket.timeout:
# There are some cases where urllib2 does not catch socket.timeout
# especially while receiving response data on an already previously
# working request
raise NameResolveError(err_str.format(msg="connection timed out"))
results = resp_data.get('results', [])
if not results:
raise NameResolveError(err_str.format(msg="no results returned"))
if resp_data.get('status', None) != 'OK':
raise NameResolveError(err_str.format(msg="unknown failure with Google maps API"))
return results
class EarthLocationInfo(QuantityInfoBase):
"""
Container for meta information like name, description, format. This is
required when the object is used as a mixin column within a table, but can
be used as a general way to store meta information.
"""
_represent_as_dict_attrs = ('x', 'y', 'z', 'ellipsoid')
def _construct_from_dict(self, map):
# Need to pop ellipsoid off and update post-instantiation. This is
# on the to-fix list in #4261.
ellipsoid = map.pop('ellipsoid')
out = self._parent_cls(**map)
out.ellipsoid = ellipsoid
return out
def new_like(self, cols, length, metadata_conflicts='warn', name=None):
"""
Return a new EarthLocation instance which is consistent with the
input ``cols`` and has ``length`` rows.
This is intended for creating an empty column object whose elements can
be set in-place for table operations like join or vstack.
Parameters
----------
cols : list
List of input columns
length : int
Length of the output column object
metadata_conflicts : str ('warn'|'error'|'silent')
How to handle metadata conflicts
name : str
Output column name
Returns
-------
col : EarthLocation (or subclass)
Empty instance of this class consistent with ``cols``
"""
# Very similar to QuantityInfo.new_like, but the creation of the
# map is different enough that this needs its own rouinte.
# Get merged info attributes shape, dtype, format, description.
attrs = self.merge_cols_attributes(cols, metadata_conflicts, name,
('meta', 'format', 'description'))
# The above raises an error if the dtypes do not match, but returns
# just the string representation, which is not useful, so remove.
attrs.pop('dtype')
# Make empty EarthLocation using the dtype and unit of the last column.
# Use zeros so we do not get problems for possible conversion to
# geodetic coordinates.
shape = (length,) + attrs.pop('shape')
data = u.Quantity(np.zeros(shape=shape, dtype=cols[0].dtype),
unit=cols[0].unit, copy=False)
# Get arguments needed to reconstruct class
map = {key: (data[key] if key in 'xyz' else getattr(cols[-1], key))
for key in self._represent_as_dict_attrs}
out = self._construct_from_dict(map)
# Set remaining info attributes
for attr, value in attrs.items():
setattr(out.info, attr, value)
return out
class EarthLocation(u.Quantity):
"""
Location on the Earth.
Initialization is first attempted assuming geocentric (x, y, z) coordinates
are given; if that fails, another attempt is made assuming geodetic
coordinates (longitude, latitude, height above a reference ellipsoid).
When using the geodetic forms, Longitudes are measured increasing to the
east, so west longitudes are negative. Internally, the coordinates are
stored as geocentric.
To ensure a specific type of coordinates is used, use the corresponding
class methods (`from_geocentric` and `from_geodetic`) or initialize the
arguments with names (``x``, ``y``, ``z`` for geocentric; ``lon``, ``lat``,
``height`` for geodetic). See the class methods for details.
Notes
-----
This class fits into the coordinates transformation framework in that it
encodes a position on the `~astropy.coordinates.ITRS` frame. To get a
proper `~astropy.coordinates.ITRS` object from this object, use the ``itrs``
property.
"""
_ellipsoid = 'WGS84'
_location_dtype = np.dtype({'names': ['x', 'y', 'z'],
'formats': [np.float64]*3})
_array_dtype = np.dtype((np.float64, (3,)))
info = EarthLocationInfo()
def __new__(cls, *args, **kwargs):
# TODO: needs copy argument and better dealing with inputs.
if (len(args) == 1 and len(kwargs) == 0 and
isinstance(args[0], EarthLocation)):
return args[0].copy()
try:
self = cls.from_geocentric(*args, **kwargs)
except (u.UnitsError, TypeError) as exc_geocentric:
try:
self = cls.from_geodetic(*args, **kwargs)
except Exception as exc_geodetic:
raise TypeError('Coordinates could not be parsed as either '
'geocentric or geodetic, with respective '
'exceptions "{0}" and "{1}"'
.format(exc_geocentric, exc_geodetic))
return self
@classmethod
def from_geocentric(cls, x, y, z, unit=None):
"""
Location on Earth, initialized from geocentric coordinates.
Parameters
----------
x, y, z : `~astropy.units.Quantity` or array-like
Cartesian coordinates. If not quantities, ``unit`` should be given.
unit : `~astropy.units.UnitBase` object or None
Physical unit of the coordinate values. If ``x``, ``y``, and/or
``z`` are quantities, they will be converted to this unit.
Raises
------
astropy.units.UnitsError
If the units on ``x``, ``y``, and ``z`` do not match or an invalid
unit is given.
ValueError
If the shapes of ``x``, ``y``, and ``z`` do not match.
TypeError
If ``x`` is not a `~astropy.units.Quantity` and no unit is given.
"""
if unit is None:
try:
unit = x.unit
except AttributeError:
raise TypeError("Geocentric coordinates should be Quantities "
"unless an explicit unit is given.")
else:
unit = u.Unit(unit)
if unit.physical_type != 'length':
raise u.UnitsError("Geocentric coordinates should be in "
"units of length.")
try:
x = u.Quantity(x, unit, copy=False)
y = u.Quantity(y, unit, copy=False)
z = u.Quantity(z, unit, copy=False)
except u.UnitsError:
raise u.UnitsError("Geocentric coordinate units should all be "
"consistent.")
x, y, z = np.broadcast_arrays(x, y, z)
struc = np.empty(x.shape, cls._location_dtype)
struc['x'], struc['y'], struc['z'] = x, y, z
return super().__new__(cls, struc, unit, copy=False)
@classmethod
def from_geodetic(cls, lon, lat, height=0., ellipsoid=None):
"""
Location on Earth, initialized from geodetic coordinates.
Parameters
----------
lon : `~astropy.coordinates.Longitude` or float
Earth East longitude. Can be anything that initialises an
`~astropy.coordinates.Angle` object (if float, in degrees).
lat : `~astropy.coordinates.Latitude` or float
Earth latitude. Can be anything that initialises an
`~astropy.coordinates.Latitude` object (if float, in degrees).
height : `~astropy.units.Quantity` or float, optional
Height above reference ellipsoid (if float, in meters; default: 0).
ellipsoid : str, optional
Name of the reference ellipsoid to use (default: 'WGS84').
Available ellipsoids are: 'WGS84', 'GRS80', 'WGS72'.
Raises
------
astropy.units.UnitsError
If the units on ``lon`` and ``lat`` are inconsistent with angular
ones, or that on ``height`` with a length.
ValueError
If ``lon``, ``lat``, and ``height`` do not have the same shape, or
if ``ellipsoid`` is not recognized as among the ones implemented.
Notes
-----
For the conversion to geocentric coordinates, the ERFA routine
``gd2gc`` is used. See https://github.com/liberfa/erfa
"""
ellipsoid = _check_ellipsoid(ellipsoid, default=cls._ellipsoid)
lon = Longitude(lon, u.degree, wrap_angle=180*u.degree, copy=False)
lat = Latitude(lat, u.degree, copy=False)
# don't convert to m by default, so we can use the height unit below.
if not isinstance(height, u.Quantity):
height = u.Quantity(height, u.m, copy=False)
# convert to float in units required for erfa routine, and ensure
# all broadcast to same shape, and are at least 1-dimensional.
_lon, _lat, _height = np.broadcast_arrays(lon.to_value(u.radian),
lat.to_value(u.radian),
height.to_value(u.m))
# get geocentric coordinates. Have to give one-dimensional array.
xyz = erfa.gd2gc(getattr(erfa, ellipsoid), _lon.ravel(),
_lat.ravel(), _height.ravel())
self = xyz.view(cls._location_dtype, cls).reshape(_lon.shape)
self._unit = u.meter
self._ellipsoid = ellipsoid
return self.to(height.unit)
@classmethod
def of_site(cls, site_name):
"""
Return an object of this class for a known observatory/site by name.
This is intended as a quick convenience function to get basic site
information, not a fully-featured exhaustive registry of observatories
and all their properties.
.. note::
When this function is called, it will attempt to download site
information from the astropy data server. If you would like a site
to be added, issue a pull request to the
`astropy-data repository <https://github.com/astropy/astropy-data>`_ .
If a site cannot be found in the registry (i.e., an internet
connection is not available), it will fall back on a built-in list,
In the future, this bundled list might include a version-controlled
list of canonical observatories extracted from the online version,
but it currently only contains the Greenwich Royal Observatory as an
example case.
Parameters
----------
site_name : str
Name of the observatory (case-insensitive).
Returns
-------
site : This class (a `~astropy.coordinates.EarthLocation` or subclass)
The location of the observatory.
See Also
--------
get_site_names : the list of sites that this function can access
"""
registry = cls._get_site_registry()
try:
el = registry[site_name]
except UnknownSiteException as e:
raise UnknownSiteException(e.site, 'EarthLocation.get_site_names', close_names=e.close_names)
if cls is el.__class__:
return el
else:
newel = cls.from_geodetic(*el.to_geodetic())
newel.info.name = el.info.name
return newel
@classmethod
def of_address(cls, address, get_height=False):
"""
Return an object of this class for a given address by querying the Google
maps geocoding API.
This is intended as a quick convenience function to get fast access to
locations. In the background, this just issues a query to the Google maps
geocoding API. It is not meant to be abused! Google uses IP-based query
limiting and will ban your IP if you send more than a few thousand queries
per hour [1]_.
.. warning::
If the query returns more than one location (e.g., searching on
``address='springfield'``), this function will use the **first** returned
location.
Parameters
----------
address : str
The address to get the location for. As per the Google maps API, this
can be a fully specified street address (e.g., 123 Main St., New York,
NY) or a city name (e.g., Danbury, CT), or etc.
get_height : bool (optional)
Use the retrieved location to perform a second query to the Google maps
elevation API to retrieve the height of the input address [2]_.
Returns
-------
location : This class (a `~astropy.coordinates.EarthLocation` or subclass)
The location of the input address.
References
----------
.. [1] https://developers.google.com/maps/documentation/geocoding/intro
.. [2] https://developers.google.com/maps/documentation/elevation/intro
"""
pars = urllib.parse.urlencode({'address': address})
geo_url = "https://maps.googleapis.com/maps/api/geocode/json?{0}".format(pars)
# get longitude and latitude location
err_str = ("Unable to retrieve coordinates for address '{address}'; {{msg}}"
.format(address=address))
geo_result = _get_json_result(geo_url, err_str=err_str)
loc = geo_result[0]['geometry']['location']
if get_height:
pars = {'locations': '{lat:.8f},{lng:.8f}'.format(lat=loc['lat'],
lng=loc['lng'])}
pars = urllib.parse.urlencode(pars)
ele_url = "https://maps.googleapis.com/maps/api/elevation/json?{0}".format(pars)
err_str = ("Unable to retrieve elevation for address '{address}'; {{msg}}"
.format(address=address))
ele_result = _get_json_result(ele_url, err_str=err_str)
height = ele_result[0]['elevation']*u.meter
else:
height = 0.
return cls.from_geodetic(lon=loc['lng']*u.degree,
lat=loc['lat']*u.degree,
height=height)
@classmethod
def get_site_names(cls):
"""
Get list of names of observatories for use with
`~astropy.coordinates.EarthLocation.of_site`.
.. note::
When this function is called, it will first attempt to
download site information from the astropy data server. If it
cannot (i.e., an internet connection is not available), it will fall
back on the list included with astropy (which is a limited and dated
set of sites). If you think a site should be added, issue a pull
request to the
`astropy-data repository <https://github.com/astropy/astropy-data>`_ .
Returns
-------
names : list of str
List of valid observatory names
See Also
--------
of_site : Gets the actual location object for one of the sites names
this returns.
"""
return cls._get_site_registry().names
@classmethod
def _get_site_registry(cls, force_download=False, force_builtin=False):
"""
Gets the site registry. The first time this either downloads or loads
from the data file packaged with astropy. Subsequent calls will use the
cached version unless explicitly overridden.
Parameters
----------
force_download : bool or str
If not False, force replacement of the cached registry with a
downloaded version. If a str, that will be used as the URL to
download from (if just True, the default URL will be used).
force_builtin : bool
If True, load from the data file bundled with astropy and set the
cache to that.
returns
-------
reg : astropy.coordinates.sites.SiteRegistry
"""
if force_builtin and force_download:
raise ValueError('Cannot have both force_builtin and force_download True')
if force_builtin:
reg = cls._site_registry = get_builtin_sites()
else:
reg = getattr(cls, '_site_registry', None)
if force_download or not reg:
try:
if isinstance(force_download, str):
reg = get_downloaded_sites(force_download)
else:
reg = get_downloaded_sites()
except OSError:
if force_download:
raise
msg = ('Could not access the online site list. Falling '
'back on the built-in version, which is rather '
'limited. If you want to retry the download, do '
'{0}._get_site_registry(force_download=True)')
warn(AstropyUserWarning(msg.format(cls.__name__)))
reg = get_builtin_sites()
cls._site_registry = reg
return reg
@property
def ellipsoid(self):
"""The default ellipsoid used to convert to geodetic coordinates."""
return self._ellipsoid
@ellipsoid.setter
def ellipsoid(self, ellipsoid):
self._ellipsoid = _check_ellipsoid(ellipsoid)
@property
def geodetic(self):
"""Convert to geodetic coordinates for the default ellipsoid."""
return self.to_geodetic()
def to_geodetic(self, ellipsoid=None):
"""Convert to geodetic coordinates.
Parameters
----------
ellipsoid : str, optional
Reference ellipsoid to use. Default is the one the coordinates
were initialized with. Available are: 'WGS84', 'GRS80', 'WGS72'
Returns
-------
(lon, lat, height) : tuple
The tuple contains instances of `~astropy.coordinates.Longitude`,
`~astropy.coordinates.Latitude`, and `~astropy.units.Quantity`
Raises
------
ValueError
if ``ellipsoid`` is not recognized as among the ones implemented.
Notes
-----
For the conversion to geodetic coordinates, the ERFA routine
``gc2gd`` is used. See https://github.com/liberfa/erfa
"""
ellipsoid = _check_ellipsoid(ellipsoid, default=self.ellipsoid)
self_array = self.to(u.meter).view(self._array_dtype, np.ndarray)
lon, lat, height = erfa.gc2gd(getattr(erfa, ellipsoid), self_array)
return GeodeticLocation(
Longitude(lon * u.radian, u.degree,
wrap_angle=180.*u.degree, copy=False),
Latitude(lat * u.radian, u.degree, copy=False),
u.Quantity(height * u.meter, self.unit, copy=False))
@property
@deprecated('2.0', alternative='`lon`', obj_type='property')
def longitude(self):
"""Longitude of the location, for the default ellipsoid."""
return self.geodetic[0]
@property
def lon(self):
"""Longitude of the location, for the default ellipsoid."""
return self.geodetic[0]
@property
@deprecated('2.0', alternative='`lat`', obj_type='property')
def latitude(self):
"""Latitude of the location, for the default ellipsoid."""
return self.geodetic[1]
@property
def lat(self):
"""Longitude of the location, for the default ellipsoid."""
return self.geodetic[1]
@property
def height(self):
"""Height of the location, for the default ellipsoid."""
return self.geodetic[2]
# mostly for symmetry with geodetic and to_geodetic.
@property
def geocentric(self):
"""Convert to a tuple with X, Y, and Z as quantities"""
return self.to_geocentric()
def to_geocentric(self):
"""Convert to a tuple with X, Y, and Z as quantities"""
return (self.x, self.y, self.z)
def get_itrs(self, obstime=None):
"""
Generates an `~astropy.coordinates.ITRS` object with the location of
this object at the requested ``obstime``.
Parameters
----------
obstime : `~astropy.time.Time` or None
The ``obstime`` to apply to the new `~astropy.coordinates.ITRS`, or
if None, the default ``obstime`` will be used.
Returns
-------
itrs : `~astropy.coordinates.ITRS`
The new object in the ITRS frame
"""
# Broadcast for a single position at multiple times, but don't attempt
# to be more general here.
if obstime and self.size == 1 and obstime.size > 1:
self = np.broadcast_to(self, obstime.shape, subok=True)
# do this here to prevent a series of complicated circular imports
from .builtin_frames import ITRS
return ITRS(x=self.x, y=self.y, z=self.z, obstime=obstime)
itrs = property(get_itrs, doc="""An `~astropy.coordinates.ITRS` object with
for the location of this object at the
default ``obstime``.""")
def get_gcrs(self, obstime):
"""GCRS position with velocity at ``obstime`` as a GCRS coordinate.
Parameters
----------
obstime : `~astropy.time.Time`
The ``obstime`` to calculate the GCRS position/velocity at.
Returns
--------
gcrs : `~astropy.coordinates.GCRS` instance
With velocity included.
"""
# do this here to prevent a series of complicated circular imports
from .builtin_frames import GCRS
itrs = self.get_itrs(obstime)
# Assume the observatory itself is fixed on the ground.
# We do a direct assignment rather than an update to avoid validation
# and creation of a new object.
zeros = np.broadcast_to(0. * u.km / u.s, (3,) + itrs.shape, subok=True)
itrs.data.differentials['s'] = CartesianDifferential(zeros)
return itrs.transform_to(GCRS(obstime=obstime))
def get_gcrs_posvel(self, obstime):
"""
Calculate the GCRS position and velocity of this object at the
requested ``obstime``.
Parameters
----------
obstime : `~astropy.time.Time`
The ``obstime`` to calculate the GCRS position/velocity at.
Returns
--------
obsgeoloc : `~astropy.coordinates.CartesianRepresentation`
The GCRS position of the object
obsgeovel : `~astropy.coordinates.CartesianRepresentation`
The GCRS velocity of the object
"""
# GCRS position
gcrs_data = self.get_gcrs(obstime).data
obsgeopos = gcrs_data.without_differentials()
obsgeovel = gcrs_data.differentials['s'].to_cartesian()
return obsgeopos, obsgeovel
def gravitational_redshift(self, obstime,
bodies=['sun', 'jupiter', 'moon'],
masses={}):
"""Return the gravitational redshift at this EarthLocation.
Calculates the gravitational redshift, of order 3 m/s, due to the
requested solar system bodies.
Parameters
----------
obstime : `~astropy.time.Time`
The ``obstime`` to calculate the redshift at.
bodies : iterable, optional
The bodies (other than the Earth) to include in the redshift
calculation. List elements should be any body name
`get_body_barycentric` accepts. Defaults to Jupiter, the Sun, and
the Moon. Earth is always included (because the class represents
an *Earth* location).
masses : dict of str to Quantity, optional
The mass or gravitational parameters (G * mass) to assume for the
bodies requested in ``bodies``. Can be used to override the
defaults for the Sun, Jupiter, the Moon, and the Earth, or to
pass in masses for other bodies.
Returns
--------
redshift : `~astropy.units.Quantity`
Gravitational redshift in velocity units at given obstime.
"""
# needs to be here to avoid circular imports
from .solar_system import get_body_barycentric
bodies = list(bodies)
# Ensure earth is included and last in the list.
if 'earth' in bodies:
bodies.remove('earth')
bodies.append('earth')
_masses = {'sun': consts.GM_sun,
'jupiter': consts.GM_jup,
'moon': consts.G * 7.34767309e22*u.kg,
'earth': consts.GM_earth}
_masses.update(masses)
GMs = []
M_GM_equivalency = (u.kg, u.Unit(consts.G * u.kg))
for body in bodies:
try:
GMs.append(_masses[body].to(u.m**3/u.s**2, [M_GM_equivalency]))
except KeyError as exc:
raise KeyError('body "{}" does not have a mass!'.format(body))
except u.UnitsError as exc:
exc.args += ('"masses" argument values must be masses or '
'gravitational parameters',)
raise
positions = [get_body_barycentric(name, obstime) for name in bodies]
# Calculate distances to objects other than earth.
distances = [(pos - positions[-1]).norm() for pos in positions[:-1]]
# Append distance from Earth's center for Earth's contribution.
distances.append(CartesianRepresentation(self.geocentric).norm())
# Get redshifts due to all objects.
redshifts = [-GM / consts.c / distance for (GM, distance) in
zip(GMs, distances)]
# Reverse order of summing, to go from small to big, and to get
# "earth" first, which gives m/s as unit.
return sum(redshifts[::-1])
@property
def x(self):
"""The X component of the geocentric coordinates."""
return self['x']
@property
def y(self):
"""The Y component of the geocentric coordinates."""
return self['y']
@property
def z(self):
"""The Z component of the geocentric coordinates."""
return self['z']
def __getitem__(self, item):
result = super().__getitem__(item)
if result.dtype is self.dtype:
return result.view(self.__class__)
else:
return result.view(u.Quantity)
def __array_finalize__(self, obj):
super().__array_finalize__(obj)
if hasattr(obj, '_ellipsoid'):
self._ellipsoid = obj._ellipsoid
def __len__(self):
if self.shape == ():
raise IndexError('0-d EarthLocation arrays cannot be indexed')
else:
return super().__len__()
def _to_value(self, unit, equivalencies=[]):
"""Helper method for to and to_value."""
# Conversion to another unit in both ``to`` and ``to_value`` goes
# via this routine. To make the regular quantity routines work, we
# temporarily turn the structured array into a regular one.
array_view = self.view(self._array_dtype, np.ndarray)
if equivalencies == []:
equivalencies = self._equivalencies
new_array = self.unit.to(unit, array_view, equivalencies=equivalencies)
return new_array.view(self.dtype).reshape(self.shape)
if NUMPY_LT_1_12:
def __repr__(self):
# Use the numpy >=1.12 way to format structured arrays.
from .representation import _array2string
prefixstr = '<' + self.__class__.__name__ + ' '
arrstr = _array2string(self.view(np.ndarray), prefix=prefixstr)
return '{0}{1}{2:s}>'.format(prefixstr, arrstr, self._unitstr)
# need to do this here at the bottom to avoid circular dependencies
from .sites import get_builtin_sites, get_downloaded_sites
|
686ce540769fad2b1a4d0964f1b44dbe442c3abbd1e33b6a04cb24c7c45c481c | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module contains the fundamental classes used for representing
coordinates in astropy.
"""
import math
from collections import namedtuple
import numpy as np
from . import angle_utilities as util
from .. import units as u
from ..utils import isiterable
__all__ = ['Angle', 'Latitude', 'Longitude']
# these are used by the `hms` and `dms` attributes
hms_tuple = namedtuple('hms_tuple', ('h', 'm', 's'))
dms_tuple = namedtuple('dms_tuple', ('d', 'm', 's'))
signed_dms_tuple = namedtuple('signed_dms_tuple', ('sign', 'd', 'm', 's'))
class Angle(u.SpecificTypeQuantity):
"""
One or more angular value(s) with units equivalent to radians or degrees.
An angle can be specified either as an array, scalar, tuple (see
below), string, `~astropy.units.Quantity` or another
:class:`~astropy.coordinates.Angle`.
The input parser is flexible and supports a variety of formats::
Angle('10.2345d')
Angle(['10.2345d', '-20d'])
Angle('1:2:30.43 degrees')
Angle('1 2 0 hours')
Angle(np.arange(1, 8), unit=u.deg)
Angle('1°2′3″')
Angle('1d2m3.4s')
Angle('-1h2m3s')
Angle('-1h2.5m')
Angle('-1:2.5', unit=u.deg)
Angle((10, 11, 12), unit='hourangle') # (h, m, s)
Angle((-1, 2, 3), unit=u.deg) # (d, m, s)
Angle(10.2345 * u.deg)
Angle(Angle(10.2345 * u.deg))
Parameters
----------
angle : `~numpy.array`, scalar, `~astropy.units.Quantity`, :class:`~astropy.coordinates.Angle`
The angle value. If a tuple, will be interpreted as ``(h, m,
s)`` or ``(d, m, s)`` depending on ``unit``. If a string, it
will be interpreted following the rules described above.
If ``angle`` is a sequence or array of strings, the resulting
values will be in the given ``unit``, or if `None` is provided,
the unit will be taken from the first given value.
unit : `~astropy.units.UnitBase`, str, optional
The unit of the value specified for the angle. This may be
any string that `~astropy.units.Unit` understands, but it is
better to give an actual unit object. Must be an angular
unit.
dtype : `~numpy.dtype`, optional
See `~astropy.units.Quantity`.
copy : bool, optional
See `~astropy.units.Quantity`.
Raises
------
`~astropy.units.UnitsError`
If a unit is not provided or it is not an angular unit.
"""
_equivalent_unit = u.radian
_include_easy_conversion_members = True
def __new__(cls, angle, unit=None, dtype=None, copy=True):
if not isinstance(angle, u.Quantity):
if unit is not None:
unit = cls._convert_unit_to_angle_unit(u.Unit(unit))
if isinstance(angle, tuple):
angle = cls._tuple_to_float(angle, unit)
elif isinstance(angle, str):
angle, angle_unit = util.parse_angle(angle, unit)
if angle_unit is None:
angle_unit = unit
if isinstance(angle, tuple):
angle = cls._tuple_to_float(angle, angle_unit)
if angle_unit is not unit:
# Possible conversion to `unit` will be done below.
angle = u.Quantity(angle, angle_unit, copy=False)
elif (isiterable(angle) and
not (isinstance(angle, np.ndarray) and
angle.dtype.kind not in 'SUVO')):
angle = [Angle(x, unit, copy=False) for x in angle]
return super().__new__(cls, angle, unit, dtype=dtype, copy=copy)
@staticmethod
def _tuple_to_float(angle, unit):
"""
Converts an angle represented as a 3-tuple or 2-tuple into a floating
point number in the given unit.
"""
# TODO: Numpy array of tuples?
if unit == u.hourangle:
return util.hms_to_hours(*angle)
elif unit == u.degree:
return util.dms_to_degrees(*angle)
else:
raise u.UnitsError("Can not parse '{0}' as unit '{1}'"
.format(angle, unit))
@staticmethod
def _convert_unit_to_angle_unit(unit):
return u.hourangle if unit is u.hour else unit
def _set_unit(self, unit):
super()._set_unit(self._convert_unit_to_angle_unit(unit))
@property
def hour(self):
"""
The angle's value in hours (read-only property).
"""
return self.hourangle
@property
def hms(self):
"""
The angle's value in hours, as a named tuple with ``(h, m, s)``
members. (This is a read-only property.)
"""
return hms_tuple(*util.hours_to_hms(self.hourangle))
@property
def dms(self):
"""
The angle's value in degrees, as a named tuple with ``(d, m, s)``
members. (This is a read-only property.)
"""
return dms_tuple(*util.degrees_to_dms(self.degree))
@property
def signed_dms(self):
"""
The angle's value in degrees, as a named tuple with ``(sign, d, m, s)``
members. The ``d``, ``m``, ``s`` are thus always positive, and the sign of
the angle is given by ``sign``. (This is a read-only property.)
This is primarily intended for use with `dms` to generate string
representations of coordinates that are correct for negative angles.
"""
return signed_dms_tuple(np.sign(self.degree),
*util.degrees_to_dms(np.abs(self.degree)))
def to_string(self, unit=None, decimal=False, sep='fromunit',
precision=None, alwayssign=False, pad=False,
fields=3, format=None):
""" A string representation of the angle.
Parameters
----------
unit : `~astropy.units.UnitBase`, optional
Specifies the unit. Must be an angular unit. If not
provided, the unit used to initialize the angle will be
used.
decimal : bool, optional
If `True`, a decimal representation will be used, otherwise
the returned string will be in sexagesimal form.
sep : str, optional
The separator between numbers in a sexagesimal
representation. E.g., if it is ':', the result is
``'12:41:11.1241'``. Also accepts 2 or 3 separators. E.g.,
``sep='hms'`` would give the result ``'12h41m11.1241s'``, or
sep='-:' would yield ``'11-21:17.124'``. Alternatively, the
special string 'fromunit' means 'dms' if the unit is
degrees, or 'hms' if the unit is hours.
precision : int, optional
The level of decimal precision. If ``decimal`` is `True`,
this is the raw precision, otherwise it gives the
precision of the last place of the sexagesimal
representation (seconds). If `None`, or not provided, the
number of decimal places is determined by the value, and
will be between 0-8 decimal places as required.
alwayssign : bool, optional
If `True`, include the sign no matter what. If `False`,
only include the sign if it is negative.
pad : bool, optional
If `True`, include leading zeros when needed to ensure a
fixed number of characters for sexagesimal representation.
fields : int, optional
Specifies the number of fields to display when outputting
sexagesimal notation. For example:
- fields == 1: ``'5d'``
- fields == 2: ``'5d45m'``
- fields == 3: ``'5d45m32.5s'``
By default, all fields are displayed.
format : str, optional
The format of the result. If not provided, an unadorned
string is returned. Supported values are:
- 'latex': Return a LaTeX-formatted string
- 'unicode': Return a string containing non-ASCII unicode
characters, such as the degree symbol
Returns
-------
strrepr : str or array
A string representation of the angle. If the angle is an array, this
will be an array with a unicode dtype.
"""
if unit is None:
unit = self.unit
else:
unit = self._convert_unit_to_angle_unit(u.Unit(unit))
separators = {
None: {
u.degree: 'dms',
u.hourangle: 'hms'},
'latex': {
u.degree: [r'^\circ', r'{}^\prime', r'{}^{\prime\prime}'],
u.hourangle: [r'^\mathrm{h}', r'^\mathrm{m}', r'^\mathrm{s}']},
'unicode': {
u.degree: '°′″',
u.hourangle: 'ʰᵐˢ'}
}
if sep == 'fromunit':
if format not in separators:
raise ValueError("Unknown format '{0}'".format(format))
seps = separators[format]
if unit in seps:
sep = seps[unit]
# Create an iterator so we can format each element of what
# might be an array.
if unit is u.degree:
if decimal:
values = self.degree
if precision is not None:
func = ("{0:0." + str(precision) + "f}").format
else:
func = '{0:g}'.format
else:
if sep == 'fromunit':
sep = 'dms'
values = self.degree
func = lambda x: util.degrees_to_string(
x, precision=precision, sep=sep, pad=pad,
fields=fields)
elif unit is u.hourangle:
if decimal:
values = self.hour
if precision is not None:
func = ("{0:0." + str(precision) + "f}").format
else:
func = '{0:g}'.format
else:
if sep == 'fromunit':
sep = 'hms'
values = self.hour
func = lambda x: util.hours_to_string(
x, precision=precision, sep=sep, pad=pad,
fields=fields)
elif unit.is_equivalent(u.radian):
if decimal:
values = self.to_value(unit)
if precision is not None:
func = ("{0:1." + str(precision) + "f}").format
else:
func = "{0:g}".format
elif sep == 'fromunit':
values = self.to_value(unit)
unit_string = unit.to_string(format=format)
if format == 'latex':
unit_string = unit_string[1:-1]
if precision is not None:
def plain_unit_format(val):
return ("{0:0." + str(precision) + "f}{1}").format(
val, unit_string)
func = plain_unit_format
else:
def plain_unit_format(val):
return "{0:g}{1}".format(val, unit_string)
func = plain_unit_format
else:
raise ValueError(
"'{0}' can not be represented in sexagesimal "
"notation".format(
unit.name))
else:
raise u.UnitsError(
"The unit value provided is not an angular unit.")
def do_format(val):
s = func(float(val))
if alwayssign and not s.startswith('-'):
s = '+' + s
if format == 'latex':
s = '${0}$'.format(s)
return s
format_ufunc = np.vectorize(do_format, otypes=['U'])
result = format_ufunc(values)
if result.ndim == 0:
result = result[()]
return result
def wrap_at(self, wrap_angle, inplace=False):
"""
Wrap the `Angle` object at the given ``wrap_angle``.
This method forces all the angle values to be within a contiguous
360 degree range so that ``wrap_angle - 360d <= angle <
wrap_angle``. By default a new Angle object is returned, but if the
``inplace`` argument is `True` then the `Angle` object is wrapped in
place and nothing is returned.
For instance::
>>> from astropy.coordinates import Angle
>>> import astropy.units as u
>>> a = Angle([-20.0, 150.0, 350.0] * u.deg)
>>> a.wrap_at(360 * u.deg).degree # Wrap into range 0 to 360 degrees # doctest: +FLOAT_CMP
array([340., 150., 350.])
>>> a.wrap_at('180d', inplace=True) # Wrap into range -180 to 180 degrees # doctest: +FLOAT_CMP
>>> a.degree # doctest: +FLOAT_CMP
array([-20., 150., -10.])
Parameters
----------
wrap_angle : str, `Angle`, angular `~astropy.units.Quantity`
Specifies a single value for the wrap angle. This can be any
object that can initialize an `Angle` object, e.g. ``'180d'``,
``180 * u.deg``, or ``Angle(180, unit=u.deg)``.
inplace : bool
If `True` then wrap the object in place instead of returning
a new `Angle`
Returns
-------
out : Angle or `None`
If ``inplace is False`` (default), return new `Angle` object
with angles wrapped accordingly. Otherwise wrap in place and
return `None`.
"""
wrap_angle = Angle(wrap_angle) # Convert to an Angle
wrapped = np.mod(self - wrap_angle, 360.0 * u.deg) - (360.0 * u.deg - wrap_angle)
if inplace:
self[()] = wrapped
else:
return wrapped
def is_within_bounds(self, lower=None, upper=None):
"""
Check if all angle(s) satisfy ``lower <= angle < upper``
If ``lower`` is not specified (or `None`) then no lower bounds check is
performed. Likewise ``upper`` can be left unspecified. For example::
>>> from astropy.coordinates import Angle
>>> import astropy.units as u
>>> a = Angle([-20, 150, 350] * u.deg)
>>> a.is_within_bounds('0d', '360d')
False
>>> a.is_within_bounds(None, '360d')
True
>>> a.is_within_bounds(-30 * u.deg, None)
True
Parameters
----------
lower : str, `Angle`, angular `~astropy.units.Quantity`, `None`
Specifies lower bound for checking. This can be any object
that can initialize an `Angle` object, e.g. ``'180d'``,
``180 * u.deg``, or ``Angle(180, unit=u.deg)``.
upper : str, `Angle`, angular `~astropy.units.Quantity`, `None`
Specifies upper bound for checking. This can be any object
that can initialize an `Angle` object, e.g. ``'180d'``,
``180 * u.deg``, or ``Angle(180, unit=u.deg)``.
Returns
-------
is_within_bounds : bool
`True` if all angles satisfy ``lower <= angle < upper``
"""
ok = True
if lower is not None:
ok &= np.all(Angle(lower) <= self)
if ok and upper is not None:
ok &= np.all(self < Angle(upper))
return bool(ok)
def __str__(self):
if self.isscalar:
return str(self.to_string())
else:
return np.array2string(self, formatter={'all': lambda x: x.to_string()})
def _repr_latex_(self):
if self.isscalar:
return self.to_string(format='latex')
else:
# Need to do a magic incantation to convert to str. Regular str
# or array2string causes all backslashes to get doubled.
return np.array2string(self, formatter={'all': lambda x: x.to_string(format='latex')})
def _no_angle_subclass(obj):
"""Return any Angle subclass objects as an Angle objects.
This is used to ensure that Latitute and Longitude change to Angle
objects when they are used in calculations (such as lon/2.)
"""
if isinstance(obj, tuple):
return tuple(_no_angle_subclass(_obj) for _obj in obj)
return obj.view(Angle) if isinstance(obj, Angle) else obj
class Latitude(Angle):
"""
Latitude-like angle(s) which must be in the range -90 to +90 deg.
A Latitude object is distinguished from a pure
:class:`~astropy.coordinates.Angle` by virtue of being constrained
so that::
-90.0 * u.deg <= angle(s) <= +90.0 * u.deg
Any attempt to set a value outside that range will result in a
`ValueError`.
The input angle(s) can be specified either as an array, list,
scalar, tuple (see below), string,
:class:`~astropy.units.Quantity` or another
:class:`~astropy.coordinates.Angle`.
The input parser is flexible and supports all of the input formats
supported by :class:`~astropy.coordinates.Angle`.
Parameters
----------
angle : array, list, scalar, `~astropy.units.Quantity`, `Angle`. The
angle value(s). If a tuple, will be interpreted as ``(h, m, s)`` or
``(d, m, s)`` depending on ``unit``. If a string, it will be
interpreted following the rules described for
:class:`~astropy.coordinates.Angle`.
If ``angle`` is a sequence or array of strings, the resulting
values will be in the given ``unit``, or if `None` is provided,
the unit will be taken from the first given value.
unit : :class:`~astropy.units.UnitBase`, str, optional
The unit of the value specified for the angle. This may be
any string that `~astropy.units.Unit` understands, but it is
better to give an actual unit object. Must be an angular
unit.
Raises
------
`~astropy.units.UnitsError`
If a unit is not provided or it is not an angular unit.
`TypeError`
If the angle parameter is an instance of :class:`~astropy.coordinates.Longitude`.
"""
def __new__(cls, angle, unit=None, **kwargs):
# Forbid creating a Lat from a Long.
if isinstance(angle, Longitude):
raise TypeError("A Latitude angle cannot be created from a Longitude angle")
self = super().__new__(cls, angle, unit=unit, **kwargs)
self._validate_angles()
return self
def _validate_angles(self, angles=None):
"""Check that angles are between -90 and 90 degrees.
If not given, the check is done on the object itself"""
# Convert the lower and upper bounds to the "native" unit of
# this angle. This limits multiplication to two values,
# rather than the N values in `self.value`. Also, the
# comparison is performed on raw arrays, rather than Quantity
# objects, for speed.
if angles is None:
angles = self
lower = u.degree.to(angles.unit, -90.0)
upper = u.degree.to(angles.unit, 90.0)
if np.any(angles.value < lower) or np.any(angles.value > upper):
raise ValueError('Latitude angle(s) must be within -90 deg <= angle <= 90 deg, '
'got {0}'.format(angles.to(u.degree)))
def __setitem__(self, item, value):
# Forbid assigning a Long to a Lat.
if isinstance(value, Longitude):
raise TypeError("A Longitude angle cannot be assigned to a Latitude angle")
# first check bounds
self._validate_angles(value)
super().__setitem__(item, value)
# Any calculation should drop to Angle
def __array_wrap__(self, obj, context=None):
obj = super().__array_wrap__(obj, context=context)
return _no_angle_subclass(obj)
def __array_ufunc__(self, *args, **kwargs):
results = super().__array_ufunc__(*args, **kwargs)
return _no_angle_subclass(results)
class LongitudeInfo(u.QuantityInfo):
_represent_as_dict_attrs = u.QuantityInfo._represent_as_dict_attrs + ('wrap_angle',)
class Longitude(Angle):
"""
Longitude-like angle(s) which are wrapped within a contiguous 360 degree range.
A ``Longitude`` object is distinguished from a pure
:class:`~astropy.coordinates.Angle` by virtue of a ``wrap_angle``
property. The ``wrap_angle`` specifies that all angle values
represented by the object will be in the range::
wrap_angle - 360 * u.deg <= angle(s) < wrap_angle
The default ``wrap_angle`` is 360 deg. Setting ``wrap_angle=180 *
u.deg`` would instead result in values between -180 and +180 deg.
Setting the ``wrap_angle`` attribute of an existing ``Longitude``
object will result in re-wrapping the angle values in-place.
The input angle(s) can be specified either as an array, list,
scalar, tuple, string, :class:`~astropy.units.Quantity`
or another :class:`~astropy.coordinates.Angle`.
The input parser is flexible and supports all of the input formats
supported by :class:`~astropy.coordinates.Angle`.
Parameters
----------
angle : array, list, scalar, `~astropy.units.Quantity`,
:class:`~astropy.coordinates.Angle` The angle value(s). If a tuple,
will be interpreted as ``(h, m s)`` or ``(d, m, s)`` depending
on ``unit``. If a string, it will be interpreted following the
rules described for :class:`~astropy.coordinates.Angle`.
If ``angle`` is a sequence or array of strings, the resulting
values will be in the given ``unit``, or if `None` is provided,
the unit will be taken from the first given value.
unit : :class:`~astropy.units.UnitBase`, str, optional
The unit of the value specified for the angle. This may be
any string that `~astropy.units.Unit` understands, but it is
better to give an actual unit object. Must be an angular
unit.
wrap_angle : :class:`~astropy.coordinates.Angle` or equivalent, or None
Angle at which to wrap back to ``wrap_angle - 360 deg``.
If ``None`` (default), it will be taken to be 360 deg unless ``angle``
has a ``wrap_angle`` attribute already (i.e., is a ``Longitude``),
in which case it will be taken from there.
Raises
------
`~astropy.units.UnitsError`
If a unit is not provided or it is not an angular unit.
`TypeError`
If the angle parameter is an instance of :class:`~astropy.coordinates.Latitude`.
"""
_wrap_angle = None
_default_wrap_angle = Angle(360 * u.deg)
info = LongitudeInfo()
def __new__(cls, angle, unit=None, wrap_angle=None, **kwargs):
# Forbid creating a Long from a Lat.
if isinstance(angle, Latitude):
raise TypeError("A Longitude angle cannot be created from "
"a Latitude angle.")
self = super().__new__(cls, angle, unit=unit, **kwargs)
if wrap_angle is None:
wrap_angle = getattr(angle, 'wrap_angle', self._default_wrap_angle)
self.wrap_angle = wrap_angle
return self
def __setitem__(self, item, value):
# Forbid assigning a Lat to a Long.
if isinstance(value, Latitude):
raise TypeError("A Latitude angle cannot be assigned to a Longitude angle")
super().__setitem__(item, value)
self._wrap_internal()
def _wrap_internal(self):
"""
Wrap the internal values in the Longitude object. Using the
:meth:`~astropy.coordinates.Angle.wrap_at` method causes
recursion.
"""
# Convert the wrap angle and 360 degrees to the native unit of
# this Angle, then do all the math on raw Numpy arrays rather
# than Quantity objects for speed.
a360 = u.degree.to(self.unit, 360.0)
wrap_angle = self.wrap_angle.to_value(self.unit)
wrap_angle_floor = wrap_angle - a360
self_angle = self.value
# Do the wrapping, but only if any angles need to be wrapped
if np.any(self_angle < wrap_angle_floor) or np.any(self_angle >= wrap_angle):
wrapped = np.mod(self_angle - wrap_angle, a360) + wrap_angle_floor
value = u.Quantity(wrapped, self.unit)
super().__setitem__((), value)
@property
def wrap_angle(self):
return self._wrap_angle
@wrap_angle.setter
def wrap_angle(self, value):
self._wrap_angle = Angle(value)
self._wrap_internal()
def __array_finalize__(self, obj):
super().__array_finalize__(obj)
self._wrap_angle = getattr(obj, '_wrap_angle',
self._default_wrap_angle)
# Any calculation should drop to Angle
def __array_wrap__(self, obj, context=None):
obj = super().__array_wrap__(obj, context=context)
return _no_angle_subclass(obj)
def __array_ufunc__(self, *args, **kwargs):
results = super().__array_ufunc__(*args, **kwargs)
return _no_angle_subclass(results)
|
ea3763baa66f3ea363789f5390e0b219cd66e715b0744f58435d2bf82dfcdb24 | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
# Dependencies
import numpy as np
import warnings
# Project
from .. import units as u
from ..utils.exceptions import AstropyDeprecationWarning
from ..utils import OrderedDescriptor, ShapedLikeNDArray
__all__ = ['Attribute', 'TimeAttribute', 'QuantityAttribute',
'EarthLocationAttribute', 'CoordinateAttribute',
'CartesianRepresentationAttribute',
'DifferentialAttribute']
class Attribute(OrderedDescriptor):
"""A non-mutable data descriptor to hold a frame attribute.
This class must be used to define frame attributes (e.g. ``equinox`` or
``obstime``) that are included in a frame class definition.
Examples
--------
The `~astropy.coordinates.FK4` class uses the following class attributes::
class FK4(BaseCoordinateFrame):
equinox = TimeAttribute(default=_EQUINOX_B1950)
obstime = TimeAttribute(default=None,
secondary_attribute='equinox')
This means that ``equinox`` and ``obstime`` are available to be set as
keyword arguments when creating an ``FK4`` class instance and are then
accessible as instance attributes. The instance value for the attribute
must be stored in ``'_' + <attribute_name>`` by the frame ``__init__``
method.
Note in this example that ``equinox`` and ``obstime`` are time attributes
and use the ``TimeAttributeFrame`` class. This subclass overrides the
``convert_input`` method to validate and convert inputs into a ``Time``
object.
Parameters
----------
default : object
Default value for the attribute if not provided
secondary_attribute : str
Name of a secondary instance attribute which supplies the value if
``default is None`` and no value was supplied during initialization.
"""
_class_attribute_ = 'frame_attributes'
_name_attribute_ = 'name'
name = '<unbound>'
def __init__(self, default=None, secondary_attribute=''):
self.default = default
self.secondary_attribute = secondary_attribute
super().__init__()
def convert_input(self, value):
"""
Validate the input ``value`` and convert to expected attribute class.
The base method here does nothing, but subclasses can implement this
as needed. The method should catch any internal exceptions and raise
ValueError with an informative message.
The method returns the validated input along with a boolean that
indicates whether the input value was actually converted. If the input
value was already the correct type then the ``converted`` return value
should be ``False``.
Parameters
----------
value : object
Input value to be converted.
Returns
-------
output_value
The ``value`` converted to the correct type (or just ``value`` if
``converted`` is False)
converted : bool
True if the conversion was actually performed, False otherwise.
Raises
------
ValueError
If the input is not valid for this attribute.
"""
return value, False
def __get__(self, instance, frame_cls=None):
if instance is None:
out = self.default
else:
out = getattr(instance, '_' + self.name, self.default)
if out is None:
out = getattr(instance, self.secondary_attribute, self.default)
out, converted = self.convert_input(out)
if instance is not None:
instance_shape = getattr(instance, 'shape', None)
if instance_shape is not None and (getattr(out, 'size', 1) > 1 and
out.shape != instance_shape):
# If the shapes do not match, try broadcasting.
try:
if isinstance(out, ShapedLikeNDArray):
out = out._apply(np.broadcast_to, shape=instance_shape,
subok=True)
else:
out = np.broadcast_to(out, instance_shape, subok=True)
except ValueError:
# raise more informative exception.
raise ValueError(
"attribute {0} should be scalar or have shape {1}, "
"but is has shape {2} and could not be broadcast."
.format(self.name, instance_shape, out.shape))
converted = True
if converted:
setattr(instance, '_' + self.name, out)
return out
def __set__(self, instance, val):
raise AttributeError('Cannot set frame attribute')
class TimeAttribute(Attribute):
"""
Frame attribute descriptor for quantities that are Time objects.
See the `~astropy.coordinates.Attribute` API doc for further
information.
Parameters
----------
default : object
Default value for the attribute if not provided
secondary_attribute : str
Name of a secondary instance attribute which supplies the value if
``default is None`` and no value was supplied during initialization.
"""
def convert_input(self, value):
"""
Convert input value to a Time object and validate by running through
the Time constructor. Also check that the input was a scalar.
Parameters
----------
value : object
Input value to be converted.
Returns
-------
out, converted : correctly-typed object, boolean
Tuple consisting of the correctly-typed object and a boolean which
indicates if conversion was actually performed.
Raises
------
ValueError
If the input is not valid for this attribute.
"""
from ..time import Time
if value is None:
return None, False
if isinstance(value, Time):
out = value
converted = False
else:
try:
out = Time(value)
except Exception as err:
raise ValueError(
'Invalid time input {0}={1!r}\n{2}'.format(self.name,
value, err))
converted = True
# Set attribute as read-only for arrays (not allowed by numpy
# for array scalars)
if out.shape:
out.writeable = False
return out, converted
class CartesianRepresentationAttribute(Attribute):
"""
A frame attribute that is a CartesianRepresentation with specified units.
Parameters
----------
default : object
Default value for the attribute if not provided
secondary_attribute : str
Name of a secondary instance attribute which supplies the value if
``default is None`` and no value was supplied during initialization.
unit : unit object or None
Name of a unit that the input will be converted into. If None, no
unit-checking or conversion is performed
"""
def __init__(self, default=None, secondary_attribute='', unit=None):
super().__init__(default, secondary_attribute)
self.unit = unit
def convert_input(self, value):
"""
Checks that the input is a CartesianRepresentation with the correct
unit, or the special value ``[0, 0, 0]``.
Parameters
----------
value : object
Input value to be converted.
Returns
-------
out, converted : correctly-typed object, boolean
Tuple consisting of the correctly-typed object and a boolean which
indicates if conversion was actually performed.
Raises
------
ValueError
If the input is not valid for this attribute.
"""
if (isinstance(value, list) and len(value) == 3 and
all(v == 0 for v in value) and self.unit is not None):
return CartesianRepresentation(np.zeros(3) * self.unit), True
else:
# is it a CartesianRepresentation with correct unit?
if hasattr(value, 'xyz') and value.xyz.unit == self.unit:
return value, False
converted = True
# if it's a CartesianRepresentation, get the xyz Quantity
value = getattr(value, 'xyz', value)
if not hasattr(value, 'unit'):
raise TypeError('tried to set a {0} with something that does '
'not have a unit.'
.format(self.__class__.__name__))
value = value.to(self.unit)
# now try and make a CartesianRepresentation.
cartrep = CartesianRepresentation(value, copy=False)
return cartrep, converted
class QuantityAttribute(Attribute):
"""
A frame attribute that is a quantity with specified units and shape
(optionally).
Parameters
----------
default : object
Default value for the attribute if not provided
secondary_attribute : str
Name of a secondary instance attribute which supplies the value if
``default is None`` and no value was supplied during initialization.
unit : unit object or None
Name of a unit that the input will be converted into. If None, no
unit-checking or conversion is performed
shape : tuple or None
If given, specifies the shape the attribute must be
"""
def __init__(self, default=None, secondary_attribute='', unit=None, shape=None):
super().__init__(default, secondary_attribute)
self.unit = unit
self.shape = shape
def convert_input(self, value):
"""
Checks that the input is a Quantity with the necessary units (or the
special value ``0``).
Parameters
----------
value : object
Input value to be converted.
Returns
-------
out, converted : correctly-typed object, boolean
Tuple consisting of the correctly-typed object and a boolean which
indicates if conversion was actually performed.
Raises
------
ValueError
If the input is not valid for this attribute.
"""
if np.all(value == 0) and self.unit is not None:
return u.Quantity(np.zeros(self.shape), self.unit), True
else:
if not hasattr(value, 'unit'):
raise TypeError('Tried to set a QuantityAttribute with '
'something that does not have a unit.')
oldvalue = value
value = u.Quantity(oldvalue, self.unit, copy=False)
if self.shape is not None and value.shape != self.shape:
raise ValueError('The provided value has shape "{0}", but '
'should have shape "{1}"'.format(value.shape,
self.shape))
converted = oldvalue is not value
return value, converted
class EarthLocationAttribute(Attribute):
"""
A frame attribute that can act as a `~astropy.coordinates.EarthLocation`.
It can be created as anything that can be transformed to the
`~astropy.coordinates.ITRS` frame, but always presents as an `EarthLocation`
when accessed after creation.
Parameters
----------
default : object
Default value for the attribute if not provided
secondary_attribute : str
Name of a secondary instance attribute which supplies the value if
``default is None`` and no value was supplied during initialization.
"""
def convert_input(self, value):
"""
Checks that the input is a Quantity with the necessary units (or the
special value ``0``).
Parameters
----------
value : object
Input value to be converted.
Returns
-------
out, converted : correctly-typed object, boolean
Tuple consisting of the correctly-typed object and a boolean which
indicates if conversion was actually performed.
Raises
------
ValueError
If the input is not valid for this attribute.
"""
if value is None:
return None, False
elif isinstance(value, EarthLocation):
return value, False
else:
# we have to do the import here because of some tricky circular deps
from .builtin_frames import ITRS
if not hasattr(value, 'transform_to'):
raise ValueError('"{0}" was passed into an '
'EarthLocationAttribute, but it does not have '
'"transform_to" method'.format(value))
itrsobj = value.transform_to(ITRS)
return itrsobj.earth_location, True
class CoordinateAttribute(Attribute):
"""
A frame attribute which is a coordinate object. It can be given as a
low-level frame class *or* a `~astropy.coordinates.SkyCoord`, but will
always be converted to the low-level frame class when accessed.
Parameters
----------
frame : a coordinate frame class
The type of frame this attribute can be
default : object
Default value for the attribute if not provided
secondary_attribute : str
Name of a secondary instance attribute which supplies the value if
``default is None`` and no value was supplied during initialization.
"""
def __init__(self, frame, default=None, secondary_attribute=''):
self._frame = frame
super().__init__(default, secondary_attribute)
def convert_input(self, value):
"""
Checks that the input is a SkyCoord with the necessary units (or the
special value ``None``).
Parameters
----------
value : object
Input value to be converted.
Returns
-------
out, converted : correctly-typed object, boolean
Tuple consisting of the correctly-typed object and a boolean which
indicates if conversion was actually performed.
Raises
------
ValueError
If the input is not valid for this attribute.
"""
if value is None:
return None, False
elif isinstance(value, self._frame):
return value, False
else:
if not hasattr(value, 'transform_to'):
raise ValueError('"{0}" was passed into a '
'CoordinateAttribute, but it does not have '
'"transform_to" method'.format(value))
transformedobj = value.transform_to(self._frame)
if hasattr(transformedobj, 'frame'):
transformedobj = transformedobj.frame
return transformedobj, True
class DifferentialAttribute(Attribute):
"""A frame attribute which is a differential instance.
The optional ``allowed_classes`` argument allows specifying a restricted
set of valid differential classes to check the input against. Otherwise,
any `~astropy.coordinates.BaseDifferential` subclass instance is valid.
Parameters
----------
default : object
Default value for the attribute if not provided
allowed_classes : tuple, optional
A list of allowed differential classes for this attribute to have.
secondary_attribute : str
Name of a secondary instance attribute which supplies the value if
``default is None`` and no value was supplied during initialization.
"""
def __init__(self, default=None, allowed_classes=None,
secondary_attribute=''):
if allowed_classes is not None:
self.allowed_classes = tuple(allowed_classes)
else:
self.allowed_classes = BaseDifferential
super().__init__(default, secondary_attribute)
def convert_input(self, value):
"""
Checks that the input is a differential object and is one of the
allowed class types.
Parameters
----------
value : object
Input value.
Returns
-------
out, converted : correctly-typed object, boolean
Tuple consisting of the correctly-typed object and a boolean which
indicates if conversion was actually performed.
Raises
------
ValueError
If the input is not valid for this attribute.
"""
if not isinstance(value, self.allowed_classes):
raise TypeError('Tried to set a DifferentialAttribute with '
'an unsupported Differential type {0}. Allowed '
'classes are: {1}'
.format(value.__class__,
self.allowed_classes))
return value, True
# Backwards-compatibility: these are the only classes that were previously
# released in v1.3
class FrameAttribute(Attribute):
def __init__(self, *args, **kwargs):
warnings.warn("FrameAttribute has been renamed to Attribute.",
AstropyDeprecationWarning)
super().__init__(*args, **kwargs)
class TimeFrameAttribute(TimeAttribute):
def __init__(self, *args, **kwargs):
warnings.warn("TimeFrameAttribute has been renamed to TimeAttribute.",
AstropyDeprecationWarning)
super().__init__(*args, **kwargs)
class QuantityFrameAttribute(QuantityAttribute):
def __init__(self, *args, **kwargs):
warnings.warn("QuantityFrameAttribute has been renamed to "
"QuantityAttribute.", AstropyDeprecationWarning)
super().__init__(*args, **kwargs)
class CartesianRepresentationFrameAttribute(CartesianRepresentationAttribute):
def __init__(self, *args, **kwargs):
warnings.warn("CartesianRepresentationFrameAttribute has been renamed "
"to CartesianRepresentationAttribute.",
AstropyDeprecationWarning)
super().__init__(*args, **kwargs)
# do this here to prevent a series of complicated circular imports
from .earth import EarthLocation
from .representation import CartesianRepresentation, BaseDifferential
|
ebb3001f081675aef04ce751a07b39b47c3b37829dfa22e3e6b8a3fdbb114c3d | # -*- coding: utf-8 -*-
# Licensed under a 3-clause BSD style license - see LICENSE.rst
# Standard library
import re
import textwrap
from datetime import datetime
from xml.dom.minidom import parse
from urllib.request import urlopen
# Third-party
from .. import time as atime
from ..utils.console import color_print, _color_text
from . import get_sun
__all__ = []
class HumanError(ValueError): pass
class CelestialError(ValueError): pass
def get_sign(dt):
"""
"""
if ((int(dt.month) == 12 and int(dt.day) >= 22)or(int(dt.month) == 1 and int(dt.day) <= 19)):
zodiac_sign = "capricorn"
elif ((int(dt.month) == 1 and int(dt.day) >= 20)or(int(dt.month) == 2 and int(dt.day) <= 17)):
zodiac_sign = "aquarius"
elif ((int(dt.month) == 2 and int(dt.day) >= 18)or(int(dt.month) == 3 and int(dt.day) <= 19)):
zodiac_sign = "pisces"
elif ((int(dt.month) == 3 and int(dt.day) >= 20)or(int(dt.month) == 4 and int(dt.day) <= 19)):
zodiac_sign = "aries"
elif ((int(dt.month) == 4 and int(dt.day) >= 20)or(int(dt.month) == 5 and int(dt.day) <= 20)):
zodiac_sign = "taurus"
elif ((int(dt.month) == 5 and int(dt.day) >= 21)or(int(dt.month) == 6 and int(dt.day) <= 20)):
zodiac_sign = "gemini"
elif ((int(dt.month) == 6 and int(dt.day) >= 21)or(int(dt.month) == 7 and int(dt.day) <= 22)):
zodiac_sign = "cancer"
elif ((int(dt.month) == 7 and int(dt.day) >= 23)or(int(dt.month) == 8 and int(dt.day) <= 22)):
zodiac_sign = "leo"
elif ((int(dt.month) == 8 and int(dt.day) >= 23)or(int(dt.month) == 9 and int(dt.day) <= 22)):
zodiac_sign = "virgo"
elif ((int(dt.month) == 9 and int(dt.day) >= 23)or(int(dt.month) == 10 and int(dt.day) <= 22)):
zodiac_sign = "libra"
elif ((int(dt.month) == 10 and int(dt.day) >= 23)or(int(dt.month) == 11 and int(dt.day) <= 21)):
zodiac_sign = "scorpio"
elif ((int(dt.month) == 11 and int(dt.day) >= 22)or(int(dt.month) == 12 and int(dt.day) <= 21)):
zodiac_sign = "sagittarius"
return zodiac_sign
_VALID_SIGNS = ["capricorn", "aquarius", "pisces", "aries", "taurus", "gemini",
"cancer", "leo", "virgo", "libra", "scorpio", "sagittarius"]
# Some of the constellation names map to different astrological "sign names".
# Astrologers really needs to talk to the IAU...
_CONST_TO_SIGNS = {'capricornus': 'capricorn', 'scorpius': 'scorpio'}
def horoscope(birthday, corrected=True):
"""
Enter your birthday as an `astropy.time.Time` object and
receive a mystical horoscope about things to come.
Parameter
---------
birthday : `astropy.time.Time`
Your birthday as a `datetime.datetime` or `astropy.time.Time` object.
corrected : bool
Whether to account for the precession of the Earth instead of using the
ancient Greek dates for the signs. After all, you do want your *real*
horoscope, not a cheap inaccurate approximation, right?
Returns
-------
Infinite wisdom, condensed into astrologically precise prose.
Notes
-----
This function was implemented on April 1. Take note of that date.
"""
special_words = {
'([sS]tar[s^ ]*)': 'yellow',
'([yY]ou[^ ]*)': 'magenta',
'([pP]lay[^ ]*)': 'blue',
'([hH]eart)': 'red',
'([fF]ate)': 'lightgreen',
}
birthday = atime.Time(birthday)
today = datetime.now()
if corrected:
zodiac_sign = get_sun(birthday).get_constellation().lower()
zodiac_sign = _CONST_TO_SIGNS.get(zodiac_sign, zodiac_sign)
if zodiac_sign not in _VALID_SIGNS:
raise HumanError('On your birthday the sun was in {}, which is not '
'a sign of the zodiac. You must not exist. Or '
'maybe you can settle for '
'corrected=False.'.format(zodiac_sign.title()))
else:
zodiac_sign = get_sign(birthday.to_datetime())
url = "http://www.findyourfate.com/rss/dailyhoroscope-feed.php?sign={sign}&id=45"
f = urlopen(url.format(sign=zodiac_sign.capitalize()))
try: # urlopen in py2 is not a decorator
doc = parse(f)
item = doc.getElementsByTagName('item')[0]
desc = item.getElementsByTagName('description')[0].childNodes[0].nodeValue
except Exception:
raise CelestialError("Invalid response from celestial gods (failed to load horoscope).")
finally:
f.close()
print("*"*79)
color_print("Horoscope for {} on {}:".format(zodiac_sign.capitalize(), today.strftime("%Y-%m-%d")),
'green')
print("*"*79)
for block in textwrap.wrap(desc, 79):
split_block = block.split()
for i, word in enumerate(split_block):
for re_word in special_words.keys():
match = re.search(re_word, word)
if match is None:
continue
split_block[i] = _color_text(match.groups()[0], special_words[re_word])
print(" ".join(split_block))
def inject_horoscope():
import astropy
astropy._yourfuture = horoscope
inject_horoscope()
|
31e08749c83acd528b0774e877277ff0f157efc03be09a216ab606b230565a29 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
# This file is automatically generated. Do not edit.
_tabversion = '3.8'
_lr_method = 'LALR'
_lr_signature = 'DA395940D76FFEB6A68EA2DB16FC015D'
_lr_action_items = {'UINT':([0,2,10,12,19,20,22,23,35,36,38,],[-7,12,-6,19,25,27,29,32,25,25,25,]),'MINUTE':([4,6,8,12,13,19,21,24,25,26,27,28,29,31,32,34,40,],[16,-14,-15,-17,-16,-9,-12,-8,-9,-13,-9,-10,36,37,38,39,-11,]),'COLON':([12,27,],[20,35,]),'$end':([1,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,19,21,22,23,24,25,26,27,28,29,30,31,32,33,34,36,37,38,39,40,41,42,43,44,],[-4,-1,-32,-5,-14,-2,-15,-3,0,-17,-16,-33,-31,-35,-24,-34,-9,-12,-25,-18,-8,-9,-13,-9,-10,-9,-26,-8,-9,-19,-8,-27,-28,-20,-21,-11,-29,-22,-30,-23,]),'SIMPLE_UNIT':([4,6,8,12,13,19,21,24,25,26,27,28,40,],[14,-14,-15,-17,-16,-9,-12,-8,-9,-13,-9,-10,-11,]),'DEGREE':([4,6,8,12,13,19,21,24,25,26,27,28,40,],[15,-14,-15,22,-16,-9,-12,-8,-9,-13,-9,-10,-11,]),'UFLOAT':([0,2,10,12,19,20,22,23,35,36,38,],[-7,13,-6,24,24,24,31,34,24,24,24,]),'HOUR':([4,6,8,12,13,19,21,24,25,26,27,28,40,],[17,-14,-15,23,-16,-9,-12,-8,-9,-13,-9,-10,-11,]),'SECOND':([4,6,8,12,13,19,21,24,25,26,27,28,40,41,42,],[18,-14,-15,-17,-16,-9,-12,-8,-9,-13,-9,-10,-11,43,44,]),'SIGN':([0,],[10,]),}
_lr_action = {}
for _k, _v in _lr_action_items.items():
for _x,_y in zip(_v[0],_v[1]):
if not _x in _lr_action: _lr_action[_x] = {}
_lr_action[_x][_k] = _y
del _lr_action_items
_lr_goto_items = {'ufloat':([12,19,20,22,23,35,36,38,],[21,26,28,30,33,40,41,42,]),'generic':([0,],[4,]),'arcminute':([0,],[1,]),'simple':([0,],[5,]),'sign':([0,],[2,]),'colon':([0,],[6,]),'dms':([0,],[7,]),'hms':([0,],[3,]),'spaced':([0,],[8,]),'angle':([0,],[11,]),'arcsecond':([0,],[9,]),}
_lr_goto = {}
for _k, _v in _lr_goto_items.items():
for _x, _y in zip(_v[0], _v[1]):
if not _x in _lr_goto: _lr_goto[_x] = {}
_lr_goto[_x][_k] = _y
del _lr_goto_items
_lr_productions = [
("S' -> angle","S'",1,None,None,None),
('angle -> hms','angle',1,'p_angle','angle_utilities.py',134),
('angle -> dms','angle',1,'p_angle','angle_utilities.py',135),
('angle -> arcsecond','angle',1,'p_angle','angle_utilities.py',136),
('angle -> arcminute','angle',1,'p_angle','angle_utilities.py',137),
('angle -> simple','angle',1,'p_angle','angle_utilities.py',138),
('sign -> SIGN','sign',1,'p_sign','angle_utilities.py',144),
('sign -> <empty>','sign',0,'p_sign','angle_utilities.py',145),
('ufloat -> UFLOAT','ufloat',1,'p_ufloat','angle_utilities.py',154),
('ufloat -> UINT','ufloat',1,'p_ufloat','angle_utilities.py',155),
('colon -> sign UINT COLON ufloat','colon',4,'p_colon','angle_utilities.py',161),
('colon -> sign UINT COLON UINT COLON ufloat','colon',6,'p_colon','angle_utilities.py',162),
('spaced -> sign UINT ufloat','spaced',3,'p_spaced','angle_utilities.py',171),
('spaced -> sign UINT UINT ufloat','spaced',4,'p_spaced','angle_utilities.py',172),
('generic -> colon','generic',1,'p_generic','angle_utilities.py',181),
('generic -> spaced','generic',1,'p_generic','angle_utilities.py',182),
('generic -> sign UFLOAT','generic',2,'p_generic','angle_utilities.py',183),
('generic -> sign UINT','generic',2,'p_generic','angle_utilities.py',184),
('hms -> sign UINT HOUR','hms',3,'p_hms','angle_utilities.py',193),
('hms -> sign UINT HOUR ufloat','hms',4,'p_hms','angle_utilities.py',194),
('hms -> sign UINT HOUR UINT MINUTE','hms',5,'p_hms','angle_utilities.py',195),
('hms -> sign UINT HOUR UFLOAT MINUTE','hms',5,'p_hms','angle_utilities.py',196),
('hms -> sign UINT HOUR UINT MINUTE ufloat','hms',6,'p_hms','angle_utilities.py',197),
('hms -> sign UINT HOUR UINT MINUTE ufloat SECOND','hms',7,'p_hms','angle_utilities.py',198),
('hms -> generic HOUR','hms',2,'p_hms','angle_utilities.py',199),
('dms -> sign UINT DEGREE','dms',3,'p_dms','angle_utilities.py',212),
('dms -> sign UINT DEGREE ufloat','dms',4,'p_dms','angle_utilities.py',213),
('dms -> sign UINT DEGREE UINT MINUTE','dms',5,'p_dms','angle_utilities.py',214),
('dms -> sign UINT DEGREE UFLOAT MINUTE','dms',5,'p_dms','angle_utilities.py',215),
('dms -> sign UINT DEGREE UINT MINUTE ufloat','dms',6,'p_dms','angle_utilities.py',216),
('dms -> sign UINT DEGREE UINT MINUTE ufloat SECOND','dms',7,'p_dms','angle_utilities.py',217),
('dms -> generic DEGREE','dms',2,'p_dms','angle_utilities.py',218),
('simple -> generic','simple',1,'p_simple','angle_utilities.py',231),
('simple -> generic SIMPLE_UNIT','simple',2,'p_simple','angle_utilities.py',232),
('arcsecond -> generic SECOND','arcsecond',2,'p_arcsecond','angle_utilities.py',241),
('arcminute -> generic MINUTE','arcminute',2,'p_arcminute','angle_utilities.py',247),
]
|
4df7ad700321b972abef569f9d60b3dc0c29bbcf946c8c719f2f0d00ae158731 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module contains standard functions for earth orientation, such as
precession and nutation.
This module is (currently) not intended to be part of the public API, but
is instead primarily for internal use in `coordinates`
"""
import numpy as np
from ..time import Time
from .. import units as u
from .matrix_utilities import rotation_matrix, matrix_product, matrix_transpose
jd1950 = Time('B1950', scale='tai').jd
jd2000 = Time('J2000', scale='utc').jd
_asecperrad = u.radian.to(u.arcsec)
def eccentricity(jd):
"""
Eccentricity of the Earth's orbit at the requested Julian Date.
Parameters
----------
jd : scalar or array-like
Julian date at which to compute the eccentricity
returns
-------
eccentricity : scalar or array
The eccentricity (or array of eccentricities)
References
----------
* Explanatory Supplement to the Astronomical Almanac: P. Kenneth
Seidelmann (ed), University Science Books (1992).
"""
T = (jd - jd1950) / 36525.0
p = (-0.000000126, - 0.00004193, 0.01673011)
return np.polyval(p, T)
def mean_lon_of_perigee(jd):
"""
Computes the mean longitude of perigee of the Earth's orbit at the
requested Julian Date.
Parameters
----------
jd : scalar or array-like
Julian date at which to compute the mean longitude of perigee
returns
-------
mean_lon_of_perigee : scalar or array
Mean longitude of perigee in degrees (or array of mean longitudes)
References
----------
* Explanatory Supplement to the Astronomical Almanac: P. Kenneth
Seidelmann (ed), University Science Books (1992).
"""
T = (jd - jd1950) / 36525.0
p = (0.012, 1.65, 6190.67, 1015489.951)
return np.polyval(p, T) / 3600.
def obliquity(jd, algorithm=2006):
"""
Computes the obliquity of the Earth at the requested Julian Date.
Parameters
----------
jd : scalar or array-like
Julian date at which to compute the obliquity
algorithm : int
Year of algorithm based on IAU adoption. Can be 2006, 2000 or 1980. The
2006 algorithm is mentioned in Circular 179, but the canonical reference
for the IAU adoption is apparently Hilton et al. 06 is composed of the
1980 algorithm with a precession-rate correction due to the 2000
precession models, and a description of the 1980 algorithm can be found
in the Explanatory Supplement to the Astronomical Almanac.
returns
-------
obliquity : scalar or array
Mean obliquity in degrees (or array of obliquities)
References
----------
* Hilton, J. et al., 2006, Celest.Mech.Dyn.Astron. 94, 351. 2000
* USNO Circular 179
* Explanatory Supplement to the Astronomical Almanac: P. Kenneth
Seidelmann (ed), University Science Books (1992).
"""
T = (jd - jd2000) / 36525.0
if algorithm == 2006:
p = (-0.0000000434, -0.000000576, 0.00200340, -0.0001831, -46.836769, 84381.406)
corr = 0
elif algorithm == 2000:
p = (0.001813, -0.00059, -46.8150, 84381.448)
corr = -0.02524 * T
elif algorithm == 1980:
p = (0.001813, -0.00059, -46.8150, 84381.448)
corr = 0
else:
raise ValueError('invalid algorithm year for computing obliquity')
return (np.polyval(p, T) + corr) / 3600.
# TODO: replace this with SOFA equivalent
def precession_matrix_Capitaine(fromepoch, toepoch):
"""
Computes the precession matrix from one Julian epoch to another.
The exact method is based on Capitaine et al. 2003, which should
match the IAU 2006 standard.
Parameters
----------
fromepoch : `~astropy.time.Time`
The epoch to precess from.
toepoch : `~astropy.time.Time`
The epoch to precess to.
Returns
-------
pmatrix : 3x3 array
Precession matrix to get from ``fromepoch`` to ``toepoch``
References
----------
USNO Circular 179
"""
mat_fromto2000 = matrix_transpose(
_precess_from_J2000_Capitaine(fromepoch.jyear))
mat_2000toto = _precess_from_J2000_Capitaine(toepoch.jyear)
return np.dot(mat_2000toto, mat_fromto2000)
def _precess_from_J2000_Capitaine(epoch):
"""
Computes the precession matrix from J2000 to the given Julian Epoch.
Expression from from Capitaine et al. 2003 as expressed in the USNO
Circular 179. This should match the IAU 2006 standard from SOFA.
Parameters
----------
epoch : scalar
The epoch as a Julian year number (e.g. J2000 is 2000.0)
"""
T = (epoch - 2000.0) / 100.0
# from USNO circular
pzeta = (-0.0000003173, -0.000005971, 0.01801828, 0.2988499, 2306.083227, 2.650545)
pz = (-0.0000002904, -0.000028596, 0.01826837, 1.0927348, 2306.077181, -2.650545)
ptheta = (-0.0000001274, -0.000007089, -0.04182264, -0.4294934, 2004.191903, 0)
zeta = np.polyval(pzeta, T) / 3600.0
z = np.polyval(pz, T) / 3600.0
theta = np.polyval(ptheta, T) / 3600.0
return matrix_product(rotation_matrix(-z, 'z'),
rotation_matrix(theta, 'y'),
rotation_matrix(-zeta, 'z'))
def _precession_matrix_besselian(epoch1, epoch2):
"""
Computes the precession matrix from one Besselian epoch to another using
Newcomb's method.
``epoch1`` and ``epoch2`` are in Besselian year numbers.
"""
# tropical years
t1 = (epoch1 - 1850.0) / 1000.0
t2 = (epoch2 - 1850.0) / 1000.0
dt = t2 - t1
zeta1 = 23035.545 + t1 * 139.720 + 0.060 * t1 * t1
zeta2 = 30.240 - 0.27 * t1
zeta3 = 17.995
pzeta = (zeta3, zeta2, zeta1, 0)
zeta = np.polyval(pzeta, dt) / 3600
z1 = 23035.545 + t1 * 139.720 + 0.060 * t1 * t1
z2 = 109.480 + 0.39 * t1
z3 = 18.325
pz = (z3, z2, z1, 0)
z = np.polyval(pz, dt) / 3600
theta1 = 20051.12 - 85.29 * t1 - 0.37 * t1 * t1
theta2 = -42.65 - 0.37 * t1
theta3 = -41.8
ptheta = (theta3, theta2, theta1, 0)
theta = np.polyval(ptheta, dt) / 3600
return matrix_product(rotation_matrix(-z, 'z'),
rotation_matrix(theta, 'y'),
rotation_matrix(-zeta, 'z'))
def _load_nutation_data(datastr, seriestype):
"""
Loads nutation series from data stored in string form.
Seriestype can be 'lunisolar' or 'planetary'
"""
if seriestype == 'lunisolar':
dtypes = [('nl', int),
('nlp', int),
('nF', int),
('nD', int),
('nOm', int),
('ps', float),
('pst', float),
('pc', float),
('ec', float),
('ect', float),
('es', float)]
elif seriestype == 'planetary':
dtypes = [('nl', int),
('nF', int),
('nD', int),
('nOm', int),
('nme', int),
('nve', int),
('nea', int),
('nma', int),
('nju', int),
('nsa', int),
('nur', int),
('nne', int),
('npa', int),
('sp', int),
('cp', int),
('se', int),
('ce', int)]
else:
raise ValueError('requested invalid nutation series type')
lines = [l for l in datastr.split('\n')
if not l.startswith('#') if not l.strip() == '']
lists = [[] for _ in dtypes]
for l in lines:
for i, e in enumerate(l.split(' ')):
lists[i].append(dtypes[i][1](e))
return np.rec.fromarrays(lists, names=[e[0] for e in dtypes])
_nut_data_00b = """
#l lprime F D Omega longitude_sin longitude_sin*t longitude_cos obliquity_cos obliquity_cos*t,obliquity_sin
0 0 0 0 1 -172064161.0 -174666.0 33386.0 92052331.0 9086.0 15377.0
0 0 2 -2 2 -13170906.0 -1675.0 -13696.0 5730336.0 -3015.0 -4587.0
0 0 2 0 2 -2276413.0 -234.0 2796.0 978459.0 -485.0 1374.0
0 0 0 0 2 2074554.0 207.0 -698.0 -897492.0 470.0 -291.0
0 1 0 0 0 1475877.0 -3633.0 11817.0 73871.0 -184.0 -1924.0
0 1 2 -2 2 -516821.0 1226.0 -524.0 224386.0 -677.0 -174.0
1 0 0 0 0 711159.0 73.0 -872.0 -6750.0 0.0 358.0
0 0 2 0 1 -387298.0 -367.0 380.0 200728.0 18.0 318.0
1 0 2 0 2 -301461.0 -36.0 816.0 129025.0 -63.0 367.0
0 -1 2 -2 2 215829.0 -494.0 111.0 -95929.0 299.0 132.0
0 0 2 -2 1 128227.0 137.0 181.0 -68982.0 -9.0 39.0
-1 0 2 0 2 123457.0 11.0 19.0 -53311.0 32.0 -4.0
-1 0 0 2 0 156994.0 10.0 -168.0 -1235.0 0.0 82.0
1 0 0 0 1 63110.0 63.0 27.0 -33228.0 0.0 -9.0
-1 0 0 0 1 -57976.0 -63.0 -189.0 31429.0 0.0 -75.0
-1 0 2 2 2 -59641.0 -11.0 149.0 25543.0 -11.0 66.0
1 0 2 0 1 -51613.0 -42.0 129.0 26366.0 0.0 78.0
-2 0 2 0 1 45893.0 50.0 31.0 -24236.0 -10.0 20.0
0 0 0 2 0 63384.0 11.0 -150.0 -1220.0 0.0 29.0
0 0 2 2 2 -38571.0 -1.0 158.0 16452.0 -11.0 68.0
0 -2 2 -2 2 32481.0 0.0 0.0 -13870.0 0.0 0.0
-2 0 0 2 0 -47722.0 0.0 -18.0 477.0 0.0 -25.0
2 0 2 0 2 -31046.0 -1.0 131.0 13238.0 -11.0 59.0
1 0 2 -2 2 28593.0 0.0 -1.0 -12338.0 10.0 -3.0
-1 0 2 0 1 20441.0 21.0 10.0 -10758.0 0.0 -3.0
2 0 0 0 0 29243.0 0.0 -74.0 -609.0 0.0 13.0
0 0 2 0 0 25887.0 0.0 -66.0 -550.0 0.0 11.0
0 1 0 0 1 -14053.0 -25.0 79.0 8551.0 -2.0 -45.0
-1 0 0 2 1 15164.0 10.0 11.0 -8001.0 0.0 -1.0
0 2 2 -2 2 -15794.0 72.0 -16.0 6850.0 -42.0 -5.0
0 0 -2 2 0 21783.0 0.0 13.0 -167.0 0.0 13.0
1 0 0 -2 1 -12873.0 -10.0 -37.0 6953.0 0.0 -14.0
0 -1 0 0 1 -12654.0 11.0 63.0 6415.0 0.0 26.0
-1 0 2 2 1 -10204.0 0.0 25.0 5222.0 0.0 15.0
0 2 0 0 0 16707.0 -85.0 -10.0 168.0 -1.0 10.0
1 0 2 2 2 -7691.0 0.0 44.0 3268.0 0.0 19.0
-2 0 2 0 0 -11024.0 0.0 -14.0 104.0 0.0 2.0
0 1 2 0 2 7566.0 -21.0 -11.0 -3250.0 0.0 -5.0
0 0 2 2 1 -6637.0 -11.0 25.0 3353.0 0.0 14.0
0 -1 2 0 2 -7141.0 21.0 8.0 3070.0 0.0 4.0
0 0 0 2 1 -6302.0 -11.0 2.0 3272.0 0.0 4.0
1 0 2 -2 1 5800.0 10.0 2.0 -3045.0 0.0 -1.0
2 0 2 -2 2 6443.0 0.0 -7.0 -2768.0 0.0 -4.0
-2 0 0 2 1 -5774.0 -11.0 -15.0 3041.0 0.0 -5.0
2 0 2 0 1 -5350.0 0.0 21.0 2695.0 0.0 12.0
0 -1 2 -2 1 -4752.0 -11.0 -3.0 2719.0 0.0 -3.0
0 0 0 -2 1 -4940.0 -11.0 -21.0 2720.0 0.0 -9.0
-1 -1 0 2 0 7350.0 0.0 -8.0 -51.0 0.0 4.0
2 0 0 -2 1 4065.0 0.0 6.0 -2206.0 0.0 1.0
1 0 0 2 0 6579.0 0.0 -24.0 -199.0 0.0 2.0
0 1 2 -2 1 3579.0 0.0 5.0 -1900.0 0.0 1.0
1 -1 0 0 0 4725.0 0.0 -6.0 -41.0 0.0 3.0
-2 0 2 0 2 -3075.0 0.0 -2.0 1313.0 0.0 -1.0
3 0 2 0 2 -2904.0 0.0 15.0 1233.0 0.0 7.0
0 -1 0 2 0 4348.0 0.0 -10.0 -81.0 0.0 2.0
1 -1 2 0 2 -2878.0 0.0 8.0 1232.0 0.0 4.0
0 0 0 1 0 -4230.0 0.0 5.0 -20.0 0.0 -2.0
-1 -1 2 2 2 -2819.0 0.0 7.0 1207.0 0.0 3.0
-1 0 2 0 0 -4056.0 0.0 5.0 40.0 0.0 -2.0
0 -1 2 2 2 -2647.0 0.0 11.0 1129.0 0.0 5.0
-2 0 0 0 1 -2294.0 0.0 -10.0 1266.0 0.0 -4.0
1 1 2 0 2 2481.0 0.0 -7.0 -1062.0 0.0 -3.0
2 0 0 0 1 2179.0 0.0 -2.0 -1129.0 0.0 -2.0
-1 1 0 1 0 3276.0 0.0 1.0 -9.0 0.0 0.0
1 1 0 0 0 -3389.0 0.0 5.0 35.0 0.0 -2.0
1 0 2 0 0 3339.0 0.0 -13.0 -107.0 0.0 1.0
-1 0 2 -2 1 -1987.0 0.0 -6.0 1073.0 0.0 -2.0
1 0 0 0 2 -1981.0 0.0 0.0 854.0 0.0 0.0
-1 0 0 1 0 4026.0 0.0 -353.0 -553.0 0.0 -139.0
0 0 2 1 2 1660.0 0.0 -5.0 -710.0 0.0 -2.0
-1 0 2 4 2 -1521.0 0.0 9.0 647.0 0.0 4.0
-1 1 0 1 1 1314.0 0.0 0.0 -700.0 0.0 0.0
0 -2 2 -2 1 -1283.0 0.0 0.0 672.0 0.0 0.0
1 0 2 2 1 -1331.0 0.0 8.0 663.0 0.0 4.0
-2 0 2 2 2 1383.0 0.0 -2.0 -594.0 0.0 -2.0
-1 0 0 0 2 1405.0 0.0 4.0 -610.0 0.0 2.0
1 1 2 -2 2 1290.0 0.0 0.0 -556.0 0.0 0.0
"""[1:-1]
_nut_data_00b = _load_nutation_data(_nut_data_00b, 'lunisolar')
# TODO: replace w/SOFA equivalent
def nutation_components2000B(jd):
"""
Computes nutation components following the IAU 2000B specification
Parameters
----------
jd : scalar
epoch at which to compute the nutation components as a JD
Returns
-------
eps : float
epsilon in radians
dpsi : float
dpsi in radians
deps : float
depsilon in raidans
"""
epsa = np.radians(obliquity(jd, 2000))
t = (jd - jd2000) / 36525
# Fundamental (Delaunay) arguments from Simon et al. (1994) via SOFA
# Mean anomaly of moon
el = ((485868.249036 + 1717915923.2178 * t) % 1296000) / _asecperrad
# Mean anomaly of sun
elp = ((1287104.79305 + 129596581.0481 * t) % 1296000) / _asecperrad
# Mean argument of the latitude of Moon
F = ((335779.526232 + 1739527262.8478 * t) % 1296000) / _asecperrad
# Mean elongation of the Moon from Sun
D = ((1072260.70369 + 1602961601.2090 * t) % 1296000) / _asecperrad
# Mean longitude of the ascending node of Moon
Om = ((450160.398036 + -6962890.5431 * t) % 1296000) / _asecperrad
# compute nutation series using array loaded from data directory
dat = _nut_data_00b
arg = dat.nl * el + dat.nlp * elp + dat.nF * F + dat.nD * D + dat.nOm * Om
sarg = np.sin(arg)
carg = np.cos(arg)
p1u_asecperrad = _asecperrad * 1e7 # 0.1 microasrcsecperrad
dpsils = np.sum((dat.ps + dat.pst * t) * sarg + dat.pc * carg) / p1u_asecperrad
depsls = np.sum((dat.ec + dat.ect * t) * carg + dat.es * sarg) / p1u_asecperrad
# fixed offset in place of planetary tersm
m_asecperrad = _asecperrad * 1e3 # milliarcsec per rad
dpsipl = -0.135 / m_asecperrad
depspl = 0.388 / m_asecperrad
return epsa, dpsils + dpsipl, depsls + depspl # all in radians
def nutation_matrix(epoch):
"""
Nutation matrix generated from nutation components.
Matrix converts from mean coordinate to true coordinate as
r_true = M * r_mean
"""
# TODO: implement higher precision 2006/2000A model if requested/needed
epsa, dpsi, deps = nutation_components2000B(epoch.jd) # all in radians
return matrix_product(rotation_matrix(-(epsa + deps), 'x', False),
rotation_matrix(-dpsi, 'z', False),
rotation_matrix(epsa, 'x', False))
|
84a7e9c91a3eedcecd8a48690673cd4212459d94a6582cfc2004a3b23e367580 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
import contextlib
import pathlib
import re
import sys
from collections import OrderedDict
from operator import itemgetter
import numpy as np
__all__ = ['register_reader', 'register_writer', 'register_identifier',
'identify_format', 'get_reader', 'get_writer', 'read', 'write',
'get_formats', 'IORegistryError', 'delay_doc_updates']
__doctest_skip__ = ['register_identifier']
_readers = OrderedDict()
_writers = OrderedDict()
_identifiers = OrderedDict()
PATH_TYPES = (str, pathlib.Path)
class IORegistryError(Exception):
"""Custom error for registry clashes.
"""
pass
# If multiple formats are added to one class the update of the docs is quite
# expensive. Classes for which the doc update is temporarly delayed are added
# to this set.
_delayed_docs_classes = set()
@contextlib.contextmanager
def delay_doc_updates(cls):
"""Contextmanager to disable documentation updates when registering
reader and writer. The documentation is only built once when the
contextmanager exits.
.. versionadded:: 1.3
Parameters
----------
cls : class
Class for which the documentation updates should be delayed.
Notes
-----
Registering mutliple readers and writers can cause significant overhead
because the documentation of the corresponding ``read`` and ``write``
methods are build every time.
.. warning::
This contextmanager is experimental and may be replaced by a more
general approach.
Examples
--------
see for example the source code of ``astropy.table.__init__``.
"""
_delayed_docs_classes.add(cls)
yield
_delayed_docs_classes.discard(cls)
_update__doc__(cls, 'read')
_update__doc__(cls, 'write')
def get_formats(data_class=None, readwrite=None):
"""
Get the list of registered I/O formats as a Table.
Parameters
----------
data_class : classobj, optional
Filter readers/writer to match data class (default = all classes).
readwrite : str or None, optional
Search only for readers (``"Read"``) or writers (``"Write"``). If None
search for both. Default is None.
.. versionadded:: 1.3
Returns
-------
format_table : Table
Table of available I/O formats.
"""
from ..table import Table
format_classes = sorted(set(_readers) | set(_writers), key=itemgetter(0))
rows = []
for format_class in format_classes:
if (data_class is not None and not _is_best_match(
data_class, format_class[1], format_classes)):
continue
has_read = 'Yes' if format_class in _readers else 'No'
has_write = 'Yes' if format_class in _writers else 'No'
has_identify = 'Yes' if format_class in _identifiers else 'No'
# Check if this is a short name (e.g. 'rdb') which is deprecated in
# favor of the full 'ascii.rdb'.
ascii_format_class = ('ascii.' + format_class[0], format_class[1])
deprecated = 'Yes' if ascii_format_class in format_classes else ''
rows.append((format_class[1].__name__, format_class[0], has_read,
has_write, has_identify, deprecated))
if readwrite is not None:
if readwrite == 'Read':
rows = [row for row in rows if row[2] == 'Yes']
elif readwrite == 'Write':
rows = [row for row in rows if row[3] == 'Yes']
else:
raise ValueError('unrecognized value for "readwrite": {0}.\n'
'Allowed are "Read" and "Write" and None.')
# Sorting the list of tuples is much faster than sorting it after the table
# is created. (#5262)
if rows:
# Indices represent "Data Class", "Deprecated" and "Format".
data = list(zip(*sorted(rows, key=itemgetter(0, 5, 1))))
else:
data = None
format_table = Table(data, names=('Data class', 'Format', 'Read', 'Write',
'Auto-identify', 'Deprecated'))
if not np.any(format_table['Deprecated'] == 'Yes'):
format_table.remove_column('Deprecated')
return format_table
def _update__doc__(data_class, readwrite):
"""
Update the docstring to include all the available readers / writers for the
``data_class.read`` or ``data_class.write`` functions (respectively).
"""
FORMATS_TEXT = 'The available built-in formats are:'
# Get the existing read or write method and its docstring
class_readwrite_func = getattr(data_class, readwrite)
if not isinstance(class_readwrite_func.__doc__, str):
# No docstring--could just be test code, or possibly code compiled
# without docstrings
return
lines = class_readwrite_func.__doc__.splitlines()
# Find the location of the existing formats table if it exists
sep_indices = [ii for ii, line in enumerate(lines) if FORMATS_TEXT in line]
if sep_indices:
# Chop off the existing formats table, including the initial blank line
chop_index = sep_indices[0]
lines = lines[:chop_index]
# Find the minimum indent, skipping the first line because it might be odd
matches = [re.search(r'(\S)', line) for line in lines[1:]]
left_indent = ' ' * min(match.start() for match in matches if match)
# Get the available unified I/O formats for this class
# Include only formats that have a reader, and drop the 'Data class' column
format_table = get_formats(data_class, readwrite.capitalize())
format_table.remove_column('Data class')
# Get the available formats as a table, then munge the output of pformat()
# a bit and put it into the docstring.
new_lines = format_table.pformat(max_lines=-1, max_width=80)
table_rst_sep = re.sub('-', '=', new_lines[1])
new_lines[1] = table_rst_sep
new_lines.insert(0, table_rst_sep)
new_lines.append(table_rst_sep)
# Check for deprecated names and include a warning at the end.
if 'Deprecated' in format_table.colnames:
new_lines.extend(['',
'Deprecated format names like ``aastex`` will be '
'removed in a future version. Use the full ',
'name (e.g. ``ascii.aastex``) instead.'])
new_lines = [FORMATS_TEXT, ''] + new_lines
lines.extend([left_indent + line for line in new_lines])
# Depending on Python version and whether class_readwrite_func is
# an instancemethod or classmethod, one of the following will work.
try:
class_readwrite_func.__doc__ = '\n'.join(lines)
except AttributeError:
class_readwrite_func.__func__.__doc__ = '\n'.join(lines)
def register_reader(data_format, data_class, function, force=False):
"""
Register a reader function.
Parameters
----------
data_format : str
The data format identifier. This is the string that will be used to
specify the data type when reading.
data_class : classobj
The class of the object that the reader produces.
function : function
The function to read in a data object.
force : bool, optional
Whether to override any existing function if already present.
Default is ``False``.
"""
if not (data_format, data_class) in _readers or force:
_readers[(data_format, data_class)] = function
else:
raise IORegistryError("Reader for format '{0}' and class '{1}' is "
'already defined'
''.format(data_format, data_class.__name__))
if data_class not in _delayed_docs_classes:
_update__doc__(data_class, 'read')
def unregister_reader(data_format, data_class):
"""
Unregister a reader function
Parameters
----------
data_format : str
The data format identifier.
data_class : classobj
The class of the object that the reader produces.
"""
if (data_format, data_class) in _readers:
_readers.pop((data_format, data_class))
else:
raise IORegistryError("No reader defined for format '{0}' and class '{1}'"
''.format(data_format, data_class.__name__))
if data_class not in _delayed_docs_classes:
_update__doc__(data_class, 'read')
def register_writer(data_format, data_class, function, force=False):
"""
Register a table writer function.
Parameters
----------
data_format : str
The data format identifier. This is the string that will be used to
specify the data type when writing.
data_class : classobj
The class of the object that can be written.
function : function
The function to write out a data object.
force : bool, optional
Whether to override any existing function if already present.
Default is ``False``.
"""
if not (data_format, data_class) in _writers or force:
_writers[(data_format, data_class)] = function
else:
raise IORegistryError("Writer for format '{0}' and class '{1}' is "
'already defined'
''.format(data_format, data_class.__name__))
if data_class not in _delayed_docs_classes:
_update__doc__(data_class, 'write')
def unregister_writer(data_format, data_class):
"""
Unregister a writer function
Parameters
----------
data_format : str
The data format identifier.
data_class : classobj
The class of the object that can be written.
"""
if (data_format, data_class) in _writers:
_writers.pop((data_format, data_class))
else:
raise IORegistryError("No writer defined for format '{0}' and class '{1}'"
''.format(data_format, data_class.__name__))
if data_class not in _delayed_docs_classes:
_update__doc__(data_class, 'write')
def register_identifier(data_format, data_class, identifier, force=False):
"""
Associate an identifier function with a specific data type.
Parameters
----------
data_format : str
The data format identifier. This is the string that is used to
specify the data type when reading/writing.
data_class : classobj
The class of the object that can be written.
identifier : function
A function that checks the argument specified to `read` or `write` to
determine whether the input can be interpreted as a table of type
``data_format``. This function should take the following arguments:
- ``origin``: A string ``"read"`` or ``"write"`` identifying whether
the file is to be opened for reading or writing.
- ``path``: The path to the file.
- ``fileobj``: An open file object to read the file's contents, or
`None` if the file could not be opened.
- ``*args``: Positional arguments for the `read` or `write`
function.
- ``**kwargs``: Keyword arguments for the `read` or `write`
function.
One or both of ``path`` or ``fileobj`` may be `None`. If they are
both `None`, the identifier will need to work from ``args[0]``.
The function should return True if the input can be identified
as being of format ``data_format``, and False otherwise.
force : bool, optional
Whether to override any existing function if already present.
Default is ``False``.
Examples
--------
To set the identifier based on extensions, for formats that take a
filename as a first argument, you can do for example::
>>> def my_identifier(*args, **kwargs):
... return isinstance(args[0], str) and args[0].endswith('.tbl')
>>> register_identifier('ipac', Table, my_identifier)
"""
if not (data_format, data_class) in _identifiers or force:
_identifiers[(data_format, data_class)] = identifier
else:
raise IORegistryError("Identifier for format '{0}' and class '{1}' is "
'already defined'.format(data_format,
data_class.__name__))
def unregister_identifier(data_format, data_class):
"""
Unregister an identifier function
Parameters
----------
data_format : str
The data format identifier.
data_class : classobj
The class of the object that can be read/written.
"""
if (data_format, data_class) in _identifiers:
_identifiers.pop((data_format, data_class))
else:
raise IORegistryError("No identifier defined for format '{0}' and class"
" '{1}'".format(data_format, data_class.__name__))
def identify_format(origin, data_class_required, path, fileobj, args, kwargs):
"""Loop through identifiers to see which formats match.
Parameters
----------
origin : str
A string ``"read`` or ``"write"`` identifying whether the file is to be
opened for reading or writing.
data_class_required : object
The specified class for the result of `read` or the class that is to be
written.
path : str, other path object or None
The path to the file or None.
fileobj : File object or None.
An open file object to read the file's contents, or ``None`` if the
file could not be opened.
args : sequence
Positional arguments for the `read` or `write` function. Note that
these must be provided as sequence.
kwargs : dict-like
Keyword arguments for the `read` or `write` function. Note that this
parameter must be `dict`-like.
Returns
-------
valid_formats : list
List of matching formats.
"""
valid_formats = []
for data_format, data_class in _identifiers:
if _is_best_match(data_class_required, data_class, _identifiers):
if _identifiers[(data_format, data_class)](
origin, path, fileobj, *args, **kwargs):
valid_formats.append(data_format)
return valid_formats
def _get_format_table_str(data_class, readwrite):
format_table = get_formats(data_class, readwrite=readwrite)
format_table.remove_column('Data class')
format_table_str = '\n'.join(format_table.pformat(max_lines=-1))
return format_table_str
def get_reader(data_format, data_class):
"""Get reader for ``data_format``.
Parameters
----------
data_format : str
The data format identifier. This is the string that is used to
specify the data type when reading/writing.
data_class : classobj
The class of the object that can be written.
Returns
-------
reader : callable
The registered reader function for this format and class.
"""
readers = [(fmt, cls) for fmt, cls in _readers if fmt == data_format]
for reader_format, reader_class in readers:
if _is_best_match(data_class, reader_class, readers):
return _readers[(reader_format, reader_class)]
else:
format_table_str = _get_format_table_str(data_class, 'Read')
raise IORegistryError(
"No reader defined for format '{0}' and class '{1}'.\nThe "
"available formats are:\n{2}".format(
data_format, data_class.__name__, format_table_str))
def get_writer(data_format, data_class):
"""Get writer for ``data_format``.
Parameters
----------
data_format : str
The data format identifier. This is the string that is used to
specify the data type when reading/writing.
data_class : classobj
The class of the object that can be written.
Returns
-------
writer : callable
The registered writer function for this format and class.
"""
writers = [(fmt, cls) for fmt, cls in _writers if fmt == data_format]
for writer_format, writer_class in writers:
if _is_best_match(data_class, writer_class, writers):
return _writers[(writer_format, writer_class)]
else:
format_table_str = _get_format_table_str(data_class, 'Write')
raise IORegistryError(
"No writer defined for format '{0}' and class '{1}'.\nThe "
"available formats are:\n{2}".format(
data_format, data_class.__name__, format_table_str))
def read(cls, *args, format=None, **kwargs):
"""
Read in data.
The arguments passed to this method depend on the format.
"""
ctx = None
try:
if format is None:
path = None
fileobj = None
if len(args):
if isinstance(args[0], PATH_TYPES):
from ..utils.data import get_readable_fileobj
# path might be a pathlib.Path object
if isinstance(args[0], pathlib.Path):
args = (str(args[0]),) + args[1:]
path = args[0]
try:
ctx = get_readable_fileobj(args[0], encoding='binary')
fileobj = ctx.__enter__()
except OSError:
raise
except Exception:
fileobj = None
else:
args = [fileobj] + list(args[1:])
elif hasattr(args[0], 'read'):
path = None
fileobj = args[0]
format = _get_valid_format(
'read', cls, path, fileobj, args, kwargs)
reader = get_reader(format, cls)
data = reader(*args, **kwargs)
if not isinstance(data, cls):
if issubclass(cls, data.__class__):
# User has read with a subclass where only the parent class is
# registered. This returns the parent class, so try coercing
# to desired subclass.
try:
data = cls(data)
except Exception:
raise TypeError('could not convert reader output to {0} '
'class.'.format(cls.__name__))
else:
raise TypeError("reader should return a {0} instance"
"".format(cls.__name__))
finally:
if ctx is not None:
ctx.__exit__(*sys.exc_info())
return data
def write(data, *args, format=None, **kwargs):
"""
Write out data.
The arguments passed to this method depend on the format.
"""
if format is None:
path = None
fileobj = None
if len(args):
if isinstance(args[0], PATH_TYPES):
# path might be a pathlib.Path object
if isinstance(args[0], pathlib.Path):
args = (str(args[0]),) + args[1:]
path = args[0]
fileobj = None
elif hasattr(args[0], 'read'):
path = None
fileobj = args[0]
format = _get_valid_format(
'write', data.__class__, path, fileobj, args, kwargs)
writer = get_writer(format, data.__class__)
writer(data, *args, **kwargs)
def _is_best_match(class1, class2, format_classes):
"""
Determine if class2 is the "best" match for class1 in the list
of classes. It is assumed that (class2 in classes) is True.
class2 is the the best match if:
- ``class1`` is a subclass of ``class2`` AND
- ``class2`` is the nearest ancestor of ``class1`` that is in classes
(which includes the case that ``class1 is class2``)
"""
if issubclass(class1, class2):
classes = {cls for fmt, cls in format_classes}
for parent in class1.__mro__:
if parent is class2: # class2 is closest registered ancestor
return True
if parent in classes: # class2 was superceded
return False
return False
def _get_valid_format(mode, cls, path, fileobj, args, kwargs):
"""
Returns the first valid format that can be used to read/write the data in
question. Mode can be either 'read' or 'write'.
"""
valid_formats = identify_format(mode, cls, path, fileobj, args, kwargs)
if len(valid_formats) == 0:
format_table_str = _get_format_table_str(cls, mode.capitalize())
raise IORegistryError("Format could not be identified.\n"
"The available formats are:\n"
"{0}".format(format_table_str))
elif len(valid_formats) > 1:
raise IORegistryError(
"Format is ambiguous - options are: {0}".format(
', '.join(sorted(valid_formats, key=itemgetter(0)))))
return valid_formats[0]
|
3514095323b3408a50df99f844f2b1a0a82a8ad14728f0e62e08263a1fbaf3a3 | """
Implements the wrapper for the Astropy test runner in the form of the
``./setup.py test`` distutils command.
"""
import os
import glob
import shutil
import subprocess
import sys
import tempfile
from setuptools import Command
class FixRemoteDataOption(type):
"""
This metaclass is used to catch cases where the user is running the tests
with --remote-data. We've now changed the --remote-data option so that it
takes arguments, but we still want --remote-data to work as before and to
enable all remote tests. With this metaclass, we can modify sys.argv
before distutils/setuptools try to parse the command-line options.
"""
def __init__(cls, name, bases, dct):
try:
idx = sys.argv.index('--remote-data')
except ValueError:
pass
else:
sys.argv[idx] = '--remote-data=any'
try:
idx = sys.argv.index('-R')
except ValueError:
pass
else:
sys.argv[idx] = '-R=any'
return super(FixRemoteDataOption, cls).__init__(name, bases, dct)
class AstropyTest(Command, metaclass=FixRemoteDataOption):
description = 'Run the tests for this package'
user_options = [
('package=', 'P',
"The name of a specific package to test, e.g. 'io.fits' or 'utils'. "
"If nothing is specified, all default tests are run."),
('test-path=', 't',
'Specify a test location by path. If a relative path to a .py file, '
'it is relative to the built package, so e.g., a leading "astropy/" '
'is necessary. If a relative path to a .rst file, it is relative to '
'the directory *below* the --docs-path directory, so a leading '
'"docs/" is usually necessary. May also be an absolute path.'),
('verbose-results', 'V',
'Turn on verbose output from pytest.'),
('plugins=', 'p',
'Plugins to enable when running pytest.'),
('pastebin=', 'b',
"Enable pytest pastebin output. Either 'all' or 'failed'."),
('args=', 'a',
'Additional arguments to be passed to pytest.'),
('remote-data=', 'R', 'Run tests that download remote data. Should be '
'one of none/astropy/any (defaults to none).'),
('pep8', '8',
'Enable PEP8 checking and disable regular tests. '
'Requires the pytest-pep8 plugin.'),
('pdb', 'd',
'Start the interactive Python debugger on errors.'),
('coverage', 'c',
'Create a coverage report. Requires the coverage package.'),
('open-files', 'o', 'Fail if any tests leave files open. Requires the '
'psutil package.'),
('parallel=', 'j',
'Run the tests in parallel on the specified number of '
'CPUs. If negative, all the cores on the machine will be '
'used. Requires the pytest-xdist plugin.'),
('docs-path=', None,
'The path to the documentation .rst files. If not provided, and '
'the current directory contains a directory called "docs", that '
'will be used.'),
('skip-docs', None,
"Don't test the documentation .rst files."),
('repeat=', None,
'How many times to repeat each test (can be used to check for '
'sporadic failures).'),
('temp-root=', None,
'The root directory in which to create the temporary testing files. '
'If unspecified the system default is used (e.g. /tmp) as explained '
'in the documentation for tempfile.mkstemp.')
]
package_name = ''
def initialize_options(self):
self.package = None
self.test_path = None
self.verbose_results = False
self.plugins = None
self.pastebin = None
self.args = None
self.remote_data = 'none'
self.pep8 = False
self.pdb = False
self.coverage = False
self.open_files = False
self.parallel = 0
self.docs_path = None
self.skip_docs = False
self.repeat = None
self.temp_root = None
def finalize_options(self):
# Normally we would validate the options here, but that's handled in
# run_tests
pass
def generate_testing_command(self):
"""
Build a Python script to run the tests.
"""
cmd_pre = '' # Commands to run before the test function
cmd_post = '' # Commands to run after the test function
if self.coverage:
pre, post = self._generate_coverage_commands()
cmd_pre += pre
cmd_post += post
set_flag = "import builtins; builtins._ASTROPY_TEST_ = True"
cmd = ('{cmd_pre}{0}; import {1.package_name}, sys; result = ('
'{1.package_name}.test('
'package={1.package!r}, '
'test_path={1.test_path!r}, '
'args={1.args!r}, '
'plugins={1.plugins!r}, '
'verbose={1.verbose_results!r}, '
'pastebin={1.pastebin!r}, '
'remote_data={1.remote_data!r}, '
'pep8={1.pep8!r}, '
'pdb={1.pdb!r}, '
'open_files={1.open_files!r}, '
'parallel={1.parallel!r}, '
'docs_path={1.docs_path!r}, '
'skip_docs={1.skip_docs!r}, '
'add_local_eggs_to_path=True, ' # see _build_temp_install below
'repeat={1.repeat!r})); '
'{cmd_post}'
'sys.exit(result)')
return cmd.format(set_flag, self, cmd_pre=cmd_pre, cmd_post=cmd_post)
def run(self):
"""
Run the tests!
"""
# Install the runtime dependencies.
if self.distribution.install_requires:
self.distribution.fetch_build_eggs(self.distribution.install_requires)
# Ensure there is a doc path
if self.docs_path is None:
cfg_docs_dir = self.distribution.get_option_dict('build_docs').get('source_dir', None)
# Some affiliated packages use this.
# See astropy/package-template#157
if cfg_docs_dir is not None and os.path.exists(cfg_docs_dir[1]):
self.docs_path = os.path.abspath(cfg_docs_dir[1])
# fall back on a default path of "docs"
elif os.path.exists('docs'): # pragma: no cover
self.docs_path = os.path.abspath('docs')
# Build a testing install of the package
self._build_temp_install()
# Install the test dependencies
# NOTE: we do this here after _build_temp_install because there is
# a weird but which occurs if psutil is installed in this way before
# astropy is built, Cython can have segmentation fault. Strange, eh?
if self.distribution.tests_require:
self.distribution.fetch_build_eggs(self.distribution.tests_require)
# Copy any additional dependencies that may have been installed via
# tests_requires or install_requires. We then pass the
# add_local_eggs_to_path=True option to package.test() to make sure the
# eggs get included in the path.
if os.path.exists('.eggs'):
shutil.copytree('.eggs', os.path.join(self.testing_path, '.eggs'))
# Run everything in a try: finally: so that the tmp dir gets deleted.
try:
# Construct this modules testing command
cmd = self.generate_testing_command()
# Run the tests in a subprocess--this is necessary since
# new extension modules may have appeared, and this is the
# easiest way to set up a new environment
testproc = subprocess.Popen(
[sys.executable, '-c', cmd],
cwd=self.testing_path, close_fds=False)
retcode = testproc.wait()
except KeyboardInterrupt:
import signal
# If a keyboard interrupt is handled, pass it to the test
# subprocess to prompt pytest to initiate its teardown
testproc.send_signal(signal.SIGINT)
retcode = testproc.wait()
finally:
# Remove temporary directory
shutil.rmtree(self.tmp_dir)
raise SystemExit(retcode)
def _build_temp_install(self):
"""
Install the package and to a temporary directory for the purposes of
testing. This allows us to test the install command, include the
entry points, and also avoids creating pyc and __pycache__ directories
inside the build directory
"""
# On OSX the default path for temp files is under /var, but in most
# cases on OSX /var is actually a symlink to /private/var; ensure we
# dereference that link, because py.test is very sensitive to relative
# paths...
tmp_dir = tempfile.mkdtemp(prefix=self.package_name + '-test-',
dir=self.temp_root)
self.tmp_dir = os.path.realpath(tmp_dir)
# We now install the package to the temporary directory. We do this
# rather than build and copy because this will ensure that e.g. entry
# points work.
self.reinitialize_command('install')
install_cmd = self.distribution.get_command_obj('install')
install_cmd.prefix = self.tmp_dir
self.run_command('install')
# We now get the path to the site-packages directory that was created
# inside self.tmp_dir
install_cmd = self.get_finalized_command('install')
self.testing_path = install_cmd.install_lib
# Ideally, docs_path is set properly in run(), but if it is still
# not set here, do not pretend it is, otherwise bad things happen.
# See astropy/package-template#157
if self.docs_path is not None:
new_docs_path = os.path.join(self.testing_path,
os.path.basename(self.docs_path))
shutil.copytree(self.docs_path, new_docs_path)
self.docs_path = new_docs_path
shutil.copy('setup.cfg', self.testing_path)
def _generate_coverage_commands(self):
"""
This method creates the post and pre commands if coverage is to be
generated
"""
if self.parallel != 0:
raise ValueError(
"--coverage can not be used with --parallel")
try:
import coverage # pylint: disable=W0611
except ImportError:
raise ImportError(
"--coverage requires that the coverage package is "
"installed.")
# Don't use get_pkg_data_filename here, because it
# requires importing astropy.config and thus screwing
# up coverage results for those packages.
coveragerc = os.path.join(
self.testing_path, self.package_name, 'tests', 'coveragerc')
with open(coveragerc, 'r') as fd:
coveragerc_content = fd.read()
coveragerc_content = coveragerc_content.replace(
"{packagename}", self.package_name)
tmp_coveragerc = os.path.join(self.tmp_dir, 'coveragerc')
with open(tmp_coveragerc, 'wb') as tmp:
tmp.write(coveragerc_content.encode('utf-8'))
cmd_pre = (
'import coverage; '
'cov = coverage.coverage(data_file="{0}", config_file="{1}"); '
'cov.start();'.format(
os.path.abspath(".coverage"), tmp_coveragerc))
cmd_post = (
'cov.stop(); '
'from astropy.tests.helper import _save_coverage; '
'_save_coverage(cov, result, "{0}", "{1}");'.format(
os.path.abspath('.'), self.testing_path))
return cmd_pre, cmd_post
|
73cb84d9665a83ab4af90e18393e507d75a9f66c47b2ba17b2ba12d8de22c505 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module is included only for backwards compatibility. Packages that
want to use these variables should now import them directly from
`astropy.tests.plugins.display` (although eventually it may be possible to
configure them within setup.cfg).
TODO: This entire module should eventually be removed once backwards
compatibility is no longer supported.
"""
import warnings
from ..utils.exceptions import AstropyDeprecationWarning
from .helper import enable_deprecations_as_exceptions
from .plugins.display import PYTEST_HEADER_MODULES, TESTED_VERSIONS
_warning_message = "The module `astropy.tests.pytest_plugins has been " \
"deprecated. The variables `PYTEST_HEADER_MODULES` and `TESTED_VERSIONS`" \
"should now be imported from `astropy.tests.plugins.display`. The function " \
"`enable_deprecations_as_exceptions` should be imported from " \
"`astropy.tests.helper`"
# Unfortunately, pytest does not display warning messages that occur within
# conftest files, which is where these variables are imported by most packages.
warnings.warn(_warning_message, AstropyDeprecationWarning)
|
2a7784b155ea6b5268bd954bb46cf5da42f5de95b7d967f44fdd3aed5bc97483 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
import importlib
import sys
import warnings
import pytest
from .helper import catch_warnings
from .. import log
from ..logger import LoggingError, conf
from ..utils.exceptions import AstropyWarning, AstropyUserWarning
# Save original values of hooks. These are not the system values, but the
# already overwritten values since the logger already gets imported before
# this file gets executed.
_excepthook = sys.__excepthook__
_showwarning = warnings.showwarning
try:
ip = get_ipython()
except NameError:
ip = None
def setup_function(function):
# Reset modules to default
importlib.reload(warnings)
importlib.reload(sys)
# Reset internal original hooks
log._showwarning_orig = None
log._excepthook_orig = None
# Set up the logger
log._set_defaults()
# Reset hooks
if log.warnings_logging_enabled():
log.disable_warnings_logging()
if log.exception_logging_enabled():
log.disable_exception_logging()
teardown_module = setup_function
def test_warnings_logging_disable_no_enable():
with pytest.raises(LoggingError) as e:
log.disable_warnings_logging()
assert e.value.args[0] == 'Warnings logging has not been enabled'
def test_warnings_logging_enable_twice():
log.enable_warnings_logging()
with pytest.raises(LoggingError) as e:
log.enable_warnings_logging()
assert e.value.args[0] == 'Warnings logging has already been enabled'
def test_warnings_logging_overridden():
log.enable_warnings_logging()
warnings.showwarning = lambda: None
with pytest.raises(LoggingError) as e:
log.disable_warnings_logging()
assert e.value.args[0] == 'Cannot disable warnings logging: warnings.showwarning was not set by this logger, or has been overridden'
def test_warnings_logging():
# Without warnings logging
with catch_warnings() as warn_list:
with log.log_to_list() as log_list:
warnings.warn("This is a warning", AstropyUserWarning)
assert len(log_list) == 0
assert len(warn_list) == 1
assert warn_list[0].message.args[0] == "This is a warning"
# With warnings logging
with catch_warnings() as warn_list:
log.enable_warnings_logging()
with log.log_to_list() as log_list:
warnings.warn("This is a warning", AstropyUserWarning)
log.disable_warnings_logging()
assert len(log_list) == 1
assert len(warn_list) == 0
assert log_list[0].levelname == 'WARNING'
assert log_list[0].message.startswith('This is a warning')
assert log_list[0].origin == 'astropy.tests.test_logger'
# With warnings logging (differentiate between Astropy and non-Astropy)
with catch_warnings() as warn_list:
log.enable_warnings_logging()
with log.log_to_list() as log_list:
warnings.warn("This is a warning", AstropyUserWarning)
warnings.warn("This is another warning, not from Astropy")
log.disable_warnings_logging()
assert len(log_list) == 1
assert len(warn_list) == 1
assert log_list[0].levelname == 'WARNING'
assert log_list[0].message.startswith('This is a warning')
assert log_list[0].origin == 'astropy.tests.test_logger'
assert warn_list[0].message.args[0] == "This is another warning, not from Astropy"
# Without warnings logging
with catch_warnings() as warn_list:
with log.log_to_list() as log_list:
warnings.warn("This is a warning", AstropyUserWarning)
assert len(log_list) == 0
assert len(warn_list) == 1
assert warn_list[0].message.args[0] == "This is a warning"
def test_warnings_logging_with_custom_class():
class CustomAstropyWarningClass(AstropyWarning):
pass
# With warnings logging
with catch_warnings() as warn_list:
log.enable_warnings_logging()
with log.log_to_list() as log_list:
warnings.warn("This is a warning", CustomAstropyWarningClass)
log.disable_warnings_logging()
assert len(log_list) == 1
assert len(warn_list) == 0
assert log_list[0].levelname == 'WARNING'
assert log_list[0].message.startswith('CustomAstropyWarningClass: This is a warning')
assert log_list[0].origin == 'astropy.tests.test_logger'
def test_warning_logging_with_io_votable_warning():
from ..io.votable.exceptions import W02, vo_warn
with catch_warnings() as warn_list:
log.enable_warnings_logging()
with log.log_to_list() as log_list:
vo_warn(W02, ('a', 'b'))
log.disable_warnings_logging()
assert len(log_list) == 1
assert len(warn_list) == 0
assert log_list[0].levelname == 'WARNING'
x = log_list[0].message.startswith(("W02: ?:?:?: W02: a attribute 'b' is "
"invalid. Must be a standard XML id"))
assert x
assert log_list[0].origin == 'astropy.tests.test_logger'
def test_import_error_in_warning_logging():
"""
Regression test for https://github.com/astropy/astropy/issues/2671
This test actually puts a goofy fake module into ``sys.modules`` to test
this problem.
"""
class FakeModule:
def __getattr__(self, attr):
raise ImportError('_showwarning should ignore any exceptions '
'here')
log.enable_warnings_logging()
sys.modules['<test fake module>'] = FakeModule()
try:
warnings.showwarning(AstropyWarning('Regression test for #2671'),
AstropyWarning, '<this is only a test>', 1)
finally:
del sys.modules['<test fake module>']
def test_exception_logging_disable_no_enable():
with pytest.raises(LoggingError) as e:
log.disable_exception_logging()
assert e.value.args[0] == 'Exception logging has not been enabled'
def test_exception_logging_enable_twice():
log.enable_exception_logging()
with pytest.raises(LoggingError) as e:
log.enable_exception_logging()
assert e.value.args[0] == 'Exception logging has already been enabled'
# You can't really override the exception handler in IPython this way, so
# this test doesn't really make sense in the IPython context.
@pytest.mark.skipif(str("ip is not None"))
def test_exception_logging_overridden():
log.enable_exception_logging()
sys.excepthook = lambda etype, evalue, tb: None
with pytest.raises(LoggingError) as e:
log.disable_exception_logging()
assert e.value.args[0] == 'Cannot disable exception logging: sys.excepthook was not set by this logger, or has been overridden'
@pytest.mark.xfail(str("ip is not None"))
def test_exception_logging():
# Without exception logging
try:
with log.log_to_list() as log_list:
raise Exception("This is an Exception")
except Exception as exc:
sys.excepthook(*sys.exc_info())
assert exc.args[0] == "This is an Exception"
else:
assert False # exception should have been raised
assert len(log_list) == 0
# With exception logging
try:
log.enable_exception_logging()
with log.log_to_list() as log_list:
raise Exception("This is an Exception")
except Exception as exc:
sys.excepthook(*sys.exc_info())
assert exc.args[0] == "This is an Exception"
else:
assert False # exception should have been raised
assert len(log_list) == 1
assert log_list[0].levelname == 'ERROR'
assert log_list[0].message.startswith('Exception: This is an Exception')
assert log_list[0].origin == 'astropy.tests.test_logger'
# Without exception logging
log.disable_exception_logging()
try:
with log.log_to_list() as log_list:
raise Exception("This is an Exception")
except Exception as exc:
sys.excepthook(*sys.exc_info())
assert exc.args[0] == "This is an Exception"
else:
assert False # exception should have been raised
assert len(log_list) == 0
@pytest.mark.xfail(str("ip is not None"))
def test_exception_logging_origin():
# The point here is to get an exception raised from another location
# and make sure the error's origin is reported correctly
from ..utils.collections import HomogeneousList
l = HomogeneousList(int)
try:
log.enable_exception_logging()
with log.log_to_list() as log_list:
l.append('foo')
except TypeError as exc:
sys.excepthook(*sys.exc_info())
assert exc.args[0].startswith(
"homogeneous list must contain only objects of type ")
else:
assert False
assert len(log_list) == 1
assert log_list[0].levelname == 'ERROR'
assert log_list[0].message.startswith(
"TypeError: homogeneous list must contain only objects of type ")
assert log_list[0].origin == 'astropy.utils.collections'
@pytest.mark.xfail(True, reason="Infinite recursion on Python 3.5+, probably a real issue")
@pytest.mark.xfail(str("ip is not None"))
def test_exception_logging_argless_exception():
"""
Regression test for a crash that occurred on Python 3 when logging an
exception that was instantiated with no arguments (no message, etc.)
Regression test for https://github.com/astropy/astropy/pull/4056
"""
try:
log.enable_exception_logging()
with log.log_to_list() as log_list:
raise Exception()
except Exception as exc:
sys.excepthook(*sys.exc_info())
else:
assert False # exception should have been raised
assert len(log_list) == 1
assert log_list[0].levelname == 'ERROR'
assert log_list[0].message == 'Exception [astropy.tests.test_logger]'
assert log_list[0].origin == 'astropy.tests.test_logger'
@pytest.mark.parametrize(('level'), [None, 'DEBUG', 'INFO', 'WARN', 'ERROR'])
def test_log_to_list(level):
orig_level = log.level
try:
if level is not None:
log.setLevel(level)
with log.log_to_list() as log_list:
log.error("Error message")
log.warning("Warning message")
log.info("Information message")
log.debug("Debug message")
finally:
log.setLevel(orig_level)
if level is None:
# The log level *should* be set to whatever it was in the config
level = conf.log_level
# Check list length
if level == 'DEBUG':
assert len(log_list) == 4
elif level == 'INFO':
assert len(log_list) == 3
elif level == 'WARN':
assert len(log_list) == 2
elif level == 'ERROR':
assert len(log_list) == 1
# Check list content
assert log_list[0].levelname == 'ERROR'
assert log_list[0].message.startswith('Error message')
assert log_list[0].origin == 'astropy.tests.test_logger'
if len(log_list) >= 2:
assert log_list[1].levelname == 'WARNING'
assert log_list[1].message.startswith('Warning message')
assert log_list[1].origin == 'astropy.tests.test_logger'
if len(log_list) >= 3:
assert log_list[2].levelname == 'INFO'
assert log_list[2].message.startswith('Information message')
assert log_list[2].origin == 'astropy.tests.test_logger'
if len(log_list) >= 4:
assert log_list[3].levelname == 'DEBUG'
assert log_list[3].message.startswith('Debug message')
assert log_list[3].origin == 'astropy.tests.test_logger'
def test_log_to_list_level():
with log.log_to_list(filter_level='ERROR') as log_list:
log.error("Error message")
log.warning("Warning message")
assert len(log_list) == 1 and log_list[0].levelname == 'ERROR'
def test_log_to_list_origin1():
with log.log_to_list(filter_origin='astropy.tests') as log_list:
log.error("Error message")
log.warning("Warning message")
assert len(log_list) == 2
def test_log_to_list_origin2():
with log.log_to_list(filter_origin='astropy.wcs') as log_list:
log.error("Error message")
log.warning("Warning message")
assert len(log_list) == 0
@pytest.mark.parametrize(('level'), [None, 'DEBUG', 'INFO', 'WARN', 'ERROR'])
def test_log_to_file(tmpdir, level):
local_path = tmpdir.join('test.log')
log_file = local_path.open('wb')
log_path = str(local_path.realpath())
orig_level = log.level
try:
if level is not None:
log.setLevel(level)
with log.log_to_file(log_path):
log.error("Error message")
log.warning("Warning message")
log.info("Information message")
log.debug("Debug message")
log_file.close()
finally:
log.setLevel(orig_level)
log_file = local_path.open('rb')
log_entries = log_file.readlines()
log_file.close()
if level is None:
# The log level *should* be set to whatever it was in the config
level = conf.log_level
# Check list length
if level == 'DEBUG':
assert len(log_entries) == 4
elif level == 'INFO':
assert len(log_entries) == 3
elif level == 'WARN':
assert len(log_entries) == 2
elif level == 'ERROR':
assert len(log_entries) == 1
# Check list content
assert eval(log_entries[0].strip())[-3:] == (
'astropy.tests.test_logger', 'ERROR', 'Error message')
if len(log_entries) >= 2:
assert eval(log_entries[1].strip())[-3:] == (
'astropy.tests.test_logger', 'WARNING', 'Warning message')
if len(log_entries) >= 3:
assert eval(log_entries[2].strip())[-3:] == (
'astropy.tests.test_logger', 'INFO', 'Information message')
if len(log_entries) >= 4:
assert eval(log_entries[3].strip())[-3:] == (
'astropy.tests.test_logger', 'DEBUG', 'Debug message')
def test_log_to_file_level(tmpdir):
local_path = tmpdir.join('test.log')
log_file = local_path.open('wb')
log_path = str(local_path.realpath())
with log.log_to_file(log_path, filter_level='ERROR'):
log.error("Error message")
log.warning("Warning message")
log_file.close()
log_file = local_path.open('rb')
log_entries = log_file.readlines()
log_file.close()
assert len(log_entries) == 1
assert eval(log_entries[0].strip())[-2:] == (
'ERROR', 'Error message')
def test_log_to_file_origin1(tmpdir):
local_path = tmpdir.join('test.log')
log_file = local_path.open('wb')
log_path = str(local_path.realpath())
with log.log_to_file(log_path, filter_origin='astropy.tests'):
log.error("Error message")
log.warning("Warning message")
log_file.close()
log_file = local_path.open('rb')
log_entries = log_file.readlines()
log_file.close()
assert len(log_entries) == 2
def test_log_to_file_origin2(tmpdir):
local_path = tmpdir.join('test.log')
log_file = local_path.open('wb')
log_path = str(local_path.realpath())
with log.log_to_file(log_path, filter_origin='astropy.wcs'):
log.error("Error message")
log.warning("Warning message")
log_file.close()
log_file = local_path.open('rb')
log_entries = log_file.readlines()
log_file.close()
assert len(log_entries) == 0
|
405ccccf29369ba6b8d77a86add0590980e6dc66c9feba4317118fa49c554ebf | """Implements the Astropy TestRunner which is a thin wrapper around py.test."""
import inspect
import os
import glob
import copy
import shlex
import sys
import tempfile
import warnings
import importlib
from collections import OrderedDict
from importlib.util import find_spec
from ..config.paths import set_temp_config, set_temp_cache
from ..utils import wraps, find_current_module
from ..utils.exceptions import AstropyWarning, AstropyDeprecationWarning
__all__ = ['TestRunner', 'TestRunnerBase', 'keyword']
def _has_test_dependencies(): # pragma: no cover
# Using the test runner will not work without these dependencies, but
# pytest-openfiles is optional, so it's not listed here.
required = ['pytest', 'pytest_remotedata', 'pytest_doctestplus']
for module in required:
spec = find_spec(module)
# Checking loader accounts for packages that were uninstalled
if spec is None or spec.loader is None:
return False
return True
class keyword:
"""
A decorator to mark a method as keyword argument for the ``TestRunner``.
Parameters
----------
default_value : `object`
The default value for the keyword argument. (Default: `None`)
priority : `int`
keyword argument methods are executed in order of descending priority.
"""
def __init__(self, default_value=None, priority=0):
self.default_value = default_value
self.priority = priority
def __call__(self, f):
def keyword(*args, **kwargs):
return f(*args, **kwargs)
keyword._default_value = self.default_value
keyword._priority = self.priority
# Set __doc__ explicitly here rather than using wraps because we want
# to keep the function name as keyword so we can inspect it later.
keyword.__doc__ = f.__doc__
return keyword
class TestRunnerBase:
"""
The base class for the TestRunner.
A test runner can be constructed by creating a subclass of this class and
defining 'keyword' methods. These are methods that have the
`~astropy.tests.runner.keyword` decorator, these methods are used to
construct allowed keyword arguments to the
`~astropy.tests.runner.TestRunnerBase.run_tests` method as a way to allow
customization of individual keyword arguments (and associated logic)
without having to re-implement the whole
`~astropy.tests.runner.TestRunnerBase.run_tests` method.
Examples
--------
A simple keyword method::
class MyRunner(TestRunnerBase):
@keyword('default_value'):
def spam(self, spam, kwargs):
\"\"\"
spam : `str`
The parameter description for the run_tests docstring.
\"\"\"
# Return value must be a list with a CLI parameter for pytest.
return ['--spam={}'.format(spam)]
"""
def __init__(self, base_path):
self.base_path = os.path.abspath(base_path)
def __new__(cls, *args, **kwargs):
# Before constructing the class parse all the methods that have been
# decorated with ``keyword``.
# The objective of this method is to construct a default set of keyword
# arguments to the ``run_tests`` method. It does this by inspecting the
# methods of the class for functions with the name ``keyword`` which is
# the name of the decorator wrapping function. Once it has created this
# dictionary, it also formats the docstring of ``run_tests`` to be
# comprised of the docstrings for the ``keyword`` methods.
# To add a keyword argument to the ``run_tests`` method, define a new
# method decorated with ``@keyword`` and with the ``self, name, kwargs``
# signature.
# Get all 'function' members as the wrapped methods are functions
functions = inspect.getmembers(cls, predicate=inspect.isfunction)
# Filter out anything that's not got the name 'keyword'
keywords = filter(lambda func: func[1].__name__ == 'keyword', functions)
# Sort all keywords based on the priority flag.
sorted_keywords = sorted(keywords, key=lambda x: x[1]._priority, reverse=True)
cls.keywords = OrderedDict()
doc_keywords = ""
for name, func in sorted_keywords:
# Here we test if the function has been overloaded to return
# NotImplemented which is the way to disable arguments on
# subclasses. If it has been disabled we need to remove it from the
# default keywords dict. We do it in the try except block because
# we do not have access to an instance of the class, so this is
# going to error unless the method is just doing `return
# NotImplemented`.
try:
# Second argument is False, as it is normally a bool.
# The other two are placeholders for objects.
if func(None, False, None) is NotImplemented:
continue
except Exception:
pass
# Construct the default kwargs dict and docstring
cls.keywords[name] = func._default_value
if func.__doc__:
doc_keywords += ' '*8
doc_keywords += func.__doc__.strip()
doc_keywords += '\n\n'
cls.run_tests.__doc__ = cls.RUN_TESTS_DOCSTRING.format(keywords=doc_keywords)
return super(TestRunnerBase, cls).__new__(cls)
def _generate_args(self, **kwargs):
# Update default values with passed kwargs
# but don't modify the defaults
keywords = copy.deepcopy(self.keywords)
keywords.update(kwargs)
# Iterate through the keywords (in order of priority)
args = []
for keyword in keywords.keys():
func = getattr(self, keyword)
result = func(keywords[keyword], keywords)
# Allow disabling of options in a subclass
if result is NotImplemented:
raise TypeError("run_tests() got an unexpected keyword argument {}".format(keyword))
# keyword methods must return a list
if not isinstance(result, list):
raise TypeError("{} keyword method must return a list".format(keyword))
args += result
return args
RUN_TESTS_DOCSTRING = \
"""
Run the tests for the package.
Parameters
----------
{keywords}
See Also
--------
pytest.main : This method builds arguments for and then calls this function.
"""
def run_tests(self, **kwargs):
# The following option will include eggs inside a .eggs folder in
# sys.path when running the tests. This is possible so that when
# runnning python setup.py test, test dependencies installed via e.g.
# tests_requires are available here. This is not an advertised option
# since it is only for internal use
if kwargs.pop('add_local_eggs_to_path', False):
# Add each egg to sys.path individually
for egg in glob.glob(os.path.join('.eggs', '*.egg')):
sys.path.insert(0, egg)
# We now need to force reload pkg_resources in case any pytest
# plugins were added above, so that their entry points are picked up
import pkg_resources
importlib.reload(pkg_resources)
if not _has_test_dependencies(): # pragma: no cover
msg = "Test dependencies are missing. You should install the 'pytest-astropy' package."
raise RuntimeError(msg)
# The docstring for this method is defined as a class variable.
# This allows it to be built for each subclass in __new__.
# Don't import pytest until it's actually needed to run the tests
import pytest
# Raise error for undefined kwargs
allowed_kwargs = set(self.keywords.keys())
passed_kwargs = set(kwargs.keys())
if not passed_kwargs.issubset(allowed_kwargs):
wrong_kwargs = list(passed_kwargs.difference(allowed_kwargs))
raise TypeError("run_tests() got an unexpected keyword argument {}".format(wrong_kwargs[0]))
args = self._generate_args(**kwargs)
if 'plugins' not in self.keywords or self.keywords['plugins'] is None:
self.keywords['plugins'] = []
# Make plugins available to test runner without registering them
self.keywords['plugins'].extend([
'astropy.tests.plugins.display',
'astropy.tests.plugins.config'
])
# override the config locations to not make a new directory nor use
# existing cache or config
astropy_config = tempfile.mkdtemp('astropy_config')
astropy_cache = tempfile.mkdtemp('astropy_cache')
# Have to use nested with statements for cross-Python support
# Note, using these context managers here is superfluous if the
# config_dir or cache_dir options to py.test are in use, but it's
# also harmless to nest the contexts
with set_temp_config(astropy_config, delete=True):
with set_temp_cache(astropy_cache, delete=True):
return pytest.main(args=args, plugins=self.keywords['plugins'])
@classmethod
def make_test_runner_in(cls, path):
"""
Constructs a `TestRunner` to run in the given path, and returns a
``test()`` function which takes the same arguments as
`TestRunner.run_tests`.
The returned ``test()`` function will be defined in the module this
was called from. This is used to implement the ``astropy.test()``
function (or the equivalent for affiliated packages).
"""
runner = cls(path)
@wraps(runner.run_tests, ('__doc__',), exclude_args=('self',))
def test(**kwargs):
return runner.run_tests(**kwargs)
module = find_current_module(2)
if module is not None:
test.__module__ = module.__name__
# A somewhat unusual hack, but delete the attached __wrapped__
# attribute--although this is normally used to tell if the function
# was wrapped with wraps, on some version of Python this is also
# used to determine the signature to display in help() which is
# not useful in this case. We don't really care in this case if the
# function was wrapped either
if hasattr(test, '__wrapped__'):
del test.__wrapped__
return test
class TestRunner(TestRunnerBase):
"""
A test runner for astropy tests
"""
# Increase priority so this warning is displayed first.
@keyword(priority=1000)
def coverage(self, coverage, kwargs):
if coverage:
warnings.warn(
"The coverage option is ignored on run_tests, since it "
"can not be made to work in that context. Use "
"'python setup.py test --coverage' instead.",
AstropyWarning)
return []
# test_path depends on self.package_path so make sure this runs before
# test_path.
@keyword(priority=1)
def package(self, package, kwargs):
"""
package : str, optional
The name of a specific package to test, e.g. 'io.fits' or 'utils'.
If nothing is specified all default Astropy tests are run.
"""
if package is None:
self.package_path = self.base_path
else:
self.package_path = os.path.join(self.base_path,
package.replace('.', os.path.sep))
if not os.path.isdir(self.package_path):
raise ValueError('Package not found: {0}'.format(package))
if not kwargs['test_path']:
return [self.package_path]
return []
@keyword()
def test_path(self, test_path, kwargs):
"""
test_path : str, optional
Specify location to test by path. May be a single file or
directory. Must be specified absolutely or relative to the
calling directory.
"""
all_args = []
# Ensure that the package kwarg has been run.
self.package(kwargs['package'], kwargs)
if test_path:
base, ext = os.path.splitext(test_path)
if ext in ('.rst', ''):
if kwargs['docs_path'] is None:
# This shouldn't happen from "python setup.py test"
raise ValueError(
"Can not test .rst files without a docs_path "
"specified.")
abs_docs_path = os.path.abspath(kwargs['docs_path'])
abs_test_path = os.path.abspath(
os.path.join(abs_docs_path, os.pardir, test_path))
common = os.path.commonprefix((abs_docs_path, abs_test_path))
if os.path.exists(abs_test_path) and common == abs_docs_path:
# Turn on the doctest_rst plugin
all_args.append('--doctest-rst')
test_path = abs_test_path
if not (os.path.isdir(test_path) or ext in ('.py', '.rst')):
raise ValueError("Test path must be a directory or a path to "
"a .py or .rst file")
return all_args + [test_path]
return []
@keyword()
def args(self, args, kwargs):
"""
args : str, optional
Additional arguments to be passed to ``pytest.main`` in the ``args``
keyword argument.
"""
if args:
return shlex.split(args, posix=not sys.platform.startswith('win'))
return []
@keyword()
def plugins(self, plugins, kwargs):
"""
plugins : list, optional
Plugins to be passed to ``pytest.main`` in the ``plugins`` keyword
argument.
"""
return []
@keyword()
def verbose(self, verbose, kwargs):
"""
verbose : bool, optional
Convenience option to turn on verbose output from py.test. Passing
True is the same as specifying ``-v`` in ``args``.
"""
if verbose:
return ['-v']
return []
@keyword()
def pastebin(self, pastebin, kwargs):
"""
pastebin : ('failed', 'all', None), optional
Convenience option for turning on py.test pastebin output. Set to
'failed' to upload info for failed tests, or 'all' to upload info
for all tests.
"""
if pastebin is not None:
if pastebin in ['failed', 'all']:
return ['--pastebin={0}'.format(pastebin)]
else:
raise ValueError("pastebin should be 'failed' or 'all'")
return []
@keyword(default_value='none')
def remote_data(self, remote_data, kwargs):
"""
remote_data : {'none', 'astropy', 'any'}, optional
Controls whether to run tests marked with @pytest.mark.remote_data. This can be
set to run no tests with remote data (``none``), only ones that use
data from http://data.astropy.org (``astropy``), or all tests that
use remote data (``any``). The default is ``none``.
"""
if remote_data is True:
remote_data = 'any'
elif remote_data is False:
remote_data = 'none'
elif remote_data not in ('none', 'astropy', 'any'):
warnings.warn("The remote_data option should be one of "
"none/astropy/any (found {0}). For backward-compatibility, "
"assuming 'any', but you should change the option to be "
"one of the supported ones to avoid issues in "
"future.".format(remote_data),
AstropyDeprecationWarning)
remote_data = 'any'
return ['--remote-data={0}'.format(remote_data)]
@keyword()
def pep8(self, pep8, kwargs):
"""
pep8 : bool, optional
Turn on PEP8 checking via the pytest-pep8 plugin and disable normal
tests. Same as specifying ``--pep8 -k pep8`` in ``args``.
"""
if pep8:
try:
import pytest_pep8 # pylint: disable=W0611
except ImportError:
raise ImportError('PEP8 checking requires pytest-pep8 plugin: '
'http://pypi.python.org/pypi/pytest-pep8')
else:
return ['--pep8', '-k', 'pep8']
return []
@keyword()
def pdb(self, pdb, kwargs):
"""
pdb : bool, optional
Turn on PDB post-mortem analysis for failing tests. Same as
specifying ``--pdb`` in ``args``.
"""
if pdb:
return ['--pdb']
return []
@keyword()
def open_files(self, open_files, kwargs):
"""
open_files : bool, optional
Fail when any tests leave files open. Off by default, because
this adds extra run time to the test suite. Requires the
``psutil`` package.
"""
if open_files:
if kwargs['parallel'] != 0:
raise SystemError(
"open file detection may not be used in conjunction with "
"parallel testing.")
try:
import psutil # pylint: disable=W0611
except ImportError:
raise SystemError(
"open file detection requested, but psutil package "
"is not installed.")
return ['--open-files']
print("Checking for unclosed files")
return []
@keyword(0)
def parallel(self, parallel, kwargs):
"""
parallel : int, optional
When provided, run the tests in parallel on the specified
number of CPUs. If parallel is negative, it will use the all
the cores on the machine. Requires the ``pytest-xdist`` plugin.
"""
if parallel != 0:
try:
from xdist import plugin # noqa
except ImportError:
raise SystemError(
"running tests in parallel requires the pytest-xdist package")
return ['-n', str(parallel)]
return []
@keyword()
def docs_path(self, docs_path, kwargs):
"""
docs_path : str, optional
The path to the documentation .rst files.
"""
if docs_path is not None and not kwargs['skip_docs']:
if kwargs['package'] is not None:
docs_path = os.path.join(
docs_path, kwargs['package'].replace('.', os.path.sep))
if not os.path.exists(docs_path):
warnings.warn(
"Can not test .rst docs, since docs path "
"({0}) does not exist.".format(docs_path))
docs_path = None
if docs_path and not kwargs['skip_docs'] and not kwargs['test_path']:
return [docs_path, '--doctest-rst']
return []
@keyword()
def skip_docs(self, skip_docs, kwargs):
"""
skip_docs : `bool`, optional
When `True`, skips running the doctests in the .rst files.
"""
# Skip docs is a bool used by docs_path only.
return []
@keyword()
def repeat(self, repeat, kwargs):
"""
repeat : `int`, optional
If set, specifies how many times each test should be run. This is
useful for diagnosing sporadic failures.
"""
if repeat:
return ['--repeat={0}'.format(repeat)]
return []
# Override run_tests for astropy-specific fixes
def run_tests(self, **kwargs):
# This prevents cyclical import problems that make it
# impossible to test packages that define Table types on their
# own.
from ..table import Table # pylint: disable=W0611
return super(TestRunner, self).run_tests(**kwargs)
|
2a115ddce0861b7f2083906e13be2b5e3ad38bc42614db852ff9aada7443ce45 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
def get_package_data():
return {
'astropy.tests': ['coveragerc'],
}
|
2b1018b9248842d86917337db9a73f1c3a0c0ddbe988ec73fb901a314444ccb1 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module provides the tools used to internally run the astropy test suite
from the installed astropy. It makes use of the `pytest` testing framework.
"""
import os
import sys
import types
import pickle
import warnings
import functools
import pytest
try:
# Import pkg_resources to prevent it from issuing warnings upon being
# imported from within py.test. See
# https://github.com/astropy/astropy/pull/537 for a detailed explanation.
import pkg_resources # pylint: disable=W0611
except ImportError:
pass
from ..utils.exceptions import (AstropyDeprecationWarning,
AstropyPendingDeprecationWarning)
# For backward-compatibility with affiliated packages
from .runner import TestRunner # pylint: disable=W0611
__all__ = ['raises', 'enable_deprecations_as_exceptions', 'remote_data',
'treat_deprecations_as_exceptions', 'catch_warnings',
'assert_follows_unicode_guidelines', 'quantity_allclose',
'assert_quantity_allclose', 'check_pickling_recovery',
'pickle_protocol', 'generic_recursive_equality_test']
# pytest marker to mark tests which get data from the web
# This is being maintained for backwards compatibility
remote_data = pytest.mark.remote_data
# distutils expects options to be Unicode strings
def _fix_user_options(options):
def to_str_or_none(x):
if x is None:
return None
return str(x)
return [tuple(to_str_or_none(x) for x in y) for y in options]
def _save_coverage(cov, result, rootdir, testing_path):
"""
This method is called after the tests have been run in coverage mode
to cleanup and then save the coverage data and report.
"""
from ..utils.console import color_print
if result != 0:
return
# The coverage report includes the full path to the temporary
# directory, so we replace all the paths with the true source
# path. Note that this will not work properly for packages that still
# rely on 2to3.
try:
# Coverage 4.0: _harvest_data has been renamed to get_data, the
# lines dict is private
cov.get_data()
except AttributeError:
# Coverage < 4.0
cov._harvest_data()
lines = cov.data.lines
else:
lines = cov.data._lines
for key in list(lines.keys()):
new_path = os.path.relpath(
os.path.realpath(key),
os.path.realpath(testing_path))
new_path = os.path.abspath(
os.path.join(rootdir, new_path))
lines[new_path] = lines.pop(key)
color_print('Saving coverage data in .coverage...', 'green')
cov.save()
color_print('Saving HTML coverage report in htmlcov...', 'green')
cov.html_report(directory=os.path.join(rootdir, 'htmlcov'))
class raises:
"""
A decorator to mark that a test should raise a given exception.
Use as follows::
@raises(ZeroDivisionError)
def test_foo():
x = 1/0
This can also be used a context manager, in which case it is just
an alias for the ``pytest.raises`` context manager (because the
two have the same name this help avoid confusion by being
flexible).
"""
# pep-8 naming exception -- this is a decorator class
def __init__(self, exc):
self._exc = exc
self._ctx = None
def __call__(self, func):
@functools.wraps(func)
def run_raises_test(*args, **kwargs):
pytest.raises(self._exc, func, *args, **kwargs)
return run_raises_test
def __enter__(self):
self._ctx = pytest.raises(self._exc)
return self._ctx.__enter__()
def __exit__(self, *exc_info):
return self._ctx.__exit__(*exc_info)
_deprecations_as_exceptions = False
_include_astropy_deprecations = True
_modules_to_ignore_on_import = set([
'compiler', # A deprecated stdlib module used by py.test
'scipy',
'pygments',
'ipykernel',
'IPython', # deprecation warnings for async and await
'setuptools'])
_warnings_to_ignore_entire_module = set([])
_warnings_to_ignore_by_pyver = {
(3, 5): set([
# py.test reads files with the 'U' flag, which is
# deprecated.
r"'U' mode is deprecated",
# py.test raised this warning in inspect on Python 3.5.
# See https://github.com/pytest-dev/pytest/pull/1009
# Keeping it since e.g. lxml as of 3.8.0 is still calling getargspec()
r"inspect\.getargspec\(\) is deprecated, use "
r"inspect\.signature\(\) instead"]),
(3, 6): set([
# py.test reads files with the 'U' flag, which is
# deprecated.
r"'U' mode is deprecated",
# inspect raises this slightly different warning on Python 3.6.
# Keeping it since e.g. lxml as of 3.8.0 is still calling getargspec()
r"inspect\.getargspec\(\) is deprecated, use "
r"inspect\.signature\(\) or inspect\.getfullargspec\(\)"])}
def enable_deprecations_as_exceptions(include_astropy_deprecations=True,
modules_to_ignore_on_import=[],
warnings_to_ignore_entire_module=[],
warnings_to_ignore_by_pyver={}):
"""
Turn on the feature that turns deprecations into exceptions.
Parameters
----------
include_astropy_deprecations : bool
If set to `True`, ``AstropyDeprecationWarning`` and
``AstropyPendingDeprecationWarning`` are also turned into exceptions.
modules_to_ignore_on_import : list of str
List of additional modules that generate deprecation warnings
on import, which are to be ignored. By default, these are already
included: ``compiler``, ``scipy``, ``pygments``, ``ipykernel``, and
``setuptools``.
warnings_to_ignore_entire_module : list of str
List of modules with deprecation warnings to ignore completely,
not just during import. If ``include_astropy_deprecations=True``
is given, ``AstropyDeprecationWarning`` and
``AstropyPendingDeprecationWarning`` are also ignored for the modules.
warnings_to_ignore_by_pyver : dict
Dictionary mapping tuple of ``(major, minor)`` Python version to
a list of deprecation warning messages to ignore. This is in
addition of those already ignored by default
(see ``_warnings_to_ignore_by_pyver`` values).
"""
global _deprecations_as_exceptions
_deprecations_as_exceptions = True
global _include_astropy_deprecations
_include_astropy_deprecations = include_astropy_deprecations
global _modules_to_ignore_on_import
_modules_to_ignore_on_import.update(modules_to_ignore_on_import)
global _warnings_to_ignore_entire_module
_warnings_to_ignore_entire_module.update(warnings_to_ignore_entire_module)
global _warnings_to_ignore_by_pyver
for key, val in warnings_to_ignore_by_pyver.items():
if key in _warnings_to_ignore_by_pyver:
_warnings_to_ignore_by_pyver[key].update(val)
else:
_warnings_to_ignore_by_pyver[key] = set(val)
def treat_deprecations_as_exceptions():
"""
Turn all DeprecationWarnings (which indicate deprecated uses of
Python itself or Numpy, but not within Astropy, where we use our
own deprecation warning class) into exceptions so that we find
out about them early.
This completely resets the warning filters and any "already seen"
warning state.
"""
# First, totally reset the warning state. The modules may change during
# this iteration thus we copy the original state to a list to iterate
# on. See https://github.com/astropy/astropy/pull/5513.
for module in list(sys.modules.values()):
# We don't want to deal with six.MovedModules, only "real"
# modules.
if (isinstance(module, types.ModuleType) and
hasattr(module, '__warningregistry__')):
del module.__warningregistry__
if not _deprecations_as_exceptions:
return
warnings.resetwarnings()
# Hide the next couple of DeprecationWarnings
warnings.simplefilter('ignore', DeprecationWarning)
# Here's the wrinkle: a couple of our third-party dependencies
# (py.test and scipy) are still using deprecated features
# themselves, and we'd like to ignore those. Fortunately, those
# show up only at import time, so if we import those things *now*,
# before we turn the warnings into exceptions, we're golden.
for m in _modules_to_ignore_on_import:
try:
__import__(m)
except ImportError:
pass
# Now, start over again with the warning filters
warnings.resetwarnings()
# Now, turn DeprecationWarnings into exceptions
_all_warns = [DeprecationWarning]
# Only turn astropy deprecation warnings into exceptions if requested
if _include_astropy_deprecations:
_all_warns += [AstropyDeprecationWarning,
AstropyPendingDeprecationWarning]
for w in _all_warns:
warnings.filterwarnings("error", ".*", w)
# This ignores all deprecation warnings from given module(s),
# not just on import, for use of Astropy affiliated packages.
for m in _warnings_to_ignore_entire_module:
for w in _all_warns:
warnings.filterwarnings('ignore', category=w, module=m)
for v in _warnings_to_ignore_by_pyver:
if sys.version_info[:2] == v:
for s in _warnings_to_ignore_by_pyver[v]:
warnings.filterwarnings("ignore", s, DeprecationWarning)
class catch_warnings(warnings.catch_warnings):
"""
A high-powered version of warnings.catch_warnings to use for testing
and to make sure that there is no dependence on the order in which
the tests are run.
This completely blitzes any memory of any warnings that have
appeared before so that all warnings will be caught and displayed.
``*args`` is a set of warning classes to collect. If no arguments are
provided, all warnings are collected.
Use as follows::
with catch_warnings(MyCustomWarning) as w:
do.something.bad()
assert len(w) > 0
"""
def __init__(self, *classes):
super(catch_warnings, self).__init__(record=True)
self.classes = classes
def __enter__(self):
warning_list = super(catch_warnings, self).__enter__()
treat_deprecations_as_exceptions()
if len(self.classes) == 0:
warnings.simplefilter('always')
else:
warnings.simplefilter('ignore')
for cls in self.classes:
warnings.simplefilter('always', cls)
return warning_list
def __exit__(self, type, value, traceback):
treat_deprecations_as_exceptions()
class ignore_warnings(catch_warnings):
"""
This can be used either as a context manager or function decorator to
ignore all warnings that occur within a function or block of code.
An optional category option can be supplied to only ignore warnings of a
certain category or categories (if a list is provided).
"""
def __init__(self, category=None):
super(ignore_warnings, self).__init__()
if isinstance(category, type) and issubclass(category, Warning):
self.category = [category]
else:
self.category = category
def __call__(self, func):
@functools.wraps(func)
def wrapper(*args, **kwargs):
# Originally this just reused self, but that doesn't work if the
# function is called more than once so we need to make a new
# context manager instance for each call
with self.__class__(category=self.category):
return func(*args, **kwargs)
return wrapper
def __enter__(self):
retval = super(ignore_warnings, self).__enter__()
if self.category is not None:
for category in self.category:
warnings.simplefilter('ignore', category)
else:
warnings.simplefilter('ignore')
return retval
def assert_follows_unicode_guidelines(
x, roundtrip=None):
"""
Test that an object follows our Unicode policy. See
"Unicode guidelines" in the coding guidelines.
Parameters
----------
x : object
The instance to test
roundtrip : module, optional
When provided, this namespace will be used to evaluate
``repr(x)`` and ensure that it roundtrips. It will also
ensure that ``__bytes__(x)`` roundtrip.
If not provided, no roundtrip testing will be performed.
"""
from .. import conf
with conf.set_temp('unicode_output', False):
bytes_x = bytes(x)
unicode_x = str(x)
repr_x = repr(x)
assert isinstance(bytes_x, bytes)
bytes_x.decode('ascii')
assert isinstance(unicode_x, str)
unicode_x.encode('ascii')
assert isinstance(repr_x, str)
if isinstance(repr_x, bytes):
repr_x.decode('ascii')
else:
repr_x.encode('ascii')
if roundtrip is not None:
assert x.__class__(bytes_x) == x
assert x.__class__(unicode_x) == x
assert eval(repr_x, roundtrip) == x
with conf.set_temp('unicode_output', True):
bytes_x = bytes(x)
unicode_x = str(x)
repr_x = repr(x)
assert isinstance(bytes_x, bytes)
bytes_x.decode('ascii')
assert isinstance(unicode_x, str)
assert isinstance(repr_x, str)
if isinstance(repr_x, bytes):
repr_x.decode('ascii')
else:
repr_x.encode('ascii')
if roundtrip is not None:
assert x.__class__(bytes_x) == x
assert x.__class__(unicode_x) == x
assert eval(repr_x, roundtrip) == x
@pytest.fixture(params=[0, 1, -1])
def pickle_protocol(request):
"""
Fixture to run all the tests for protocols 0 and 1, and -1 (most advanced).
(Originally from astropy.table.tests.test_pickle)
"""
return request.param
def generic_recursive_equality_test(a, b, class_history):
"""
Check if the attributes of a and b are equal. Then,
check if the attributes of the attributes are equal.
"""
dict_a = a.__dict__
dict_b = b.__dict__
for key in dict_a:
assert key in dict_b,\
"Did not pickle {0}".format(key)
if hasattr(dict_a[key], '__eq__'):
eq = (dict_a[key] == dict_b[key])
if '__iter__' in dir(eq):
eq = (False not in eq)
assert eq, "Value of {0} changed by pickling".format(key)
if hasattr(dict_a[key], '__dict__'):
if dict_a[key].__class__ in class_history:
# attempt to prevent infinite recursion
pass
else:
new_class_history = [dict_a[key].__class__]
new_class_history.extend(class_history)
generic_recursive_equality_test(dict_a[key],
dict_b[key],
new_class_history)
def check_pickling_recovery(original, protocol):
"""
Try to pickle an object. If successful, make sure
the object's attributes survived pickling and unpickling.
"""
f = pickle.dumps(original, protocol=protocol)
unpickled = pickle.loads(f)
class_history = [original.__class__]
generic_recursive_equality_test(original, unpickled,
class_history)
def assert_quantity_allclose(actual, desired, rtol=1.e-7, atol=None,
**kwargs):
"""
Raise an assertion if two objects are not equal up to desired tolerance.
This is a :class:`~astropy.units.Quantity`-aware version of
:func:`numpy.testing.assert_allclose`.
"""
import numpy as np
np.testing.assert_allclose(*_unquantify_allclose_arguments(actual, desired,
rtol, atol),
**kwargs)
def quantity_allclose(a, b, rtol=1.e-5, atol=None, **kwargs):
"""
Returns True if two arrays are element-wise equal within a tolerance.
This is a :class:`~astropy.units.Quantity`-aware version of
:func:`numpy.allclose`.
"""
import numpy as np
return np.allclose(*_unquantify_allclose_arguments(a, b, rtol, atol),
**kwargs)
def _unquantify_allclose_arguments(actual, desired, rtol, atol):
from .. import units as u
actual = u.Quantity(actual, subok=True, copy=False)
desired = u.Quantity(desired, subok=True, copy=False)
try:
desired = desired.to(actual.unit)
except u.UnitsError:
raise u.UnitsError("Units for 'desired' ({0}) and 'actual' ({1}) "
"are not convertible"
.format(desired.unit, actual.unit))
if atol is None:
# by default, we assume an absolute tolerance of 0
atol = u.Quantity(0)
else:
atol = u.Quantity(atol, subok=True, copy=False)
try:
atol = atol.to(actual.unit)
except u.UnitsError:
raise u.UnitsError("Units for 'atol' ({0}) and 'actual' ({1}) "
"are not convertible"
.format(atol.unit, actual.unit))
rtol = u.Quantity(rtol, subok=True, copy=False)
try:
rtol = rtol.to(u.dimensionless_unscaled)
except Exception:
raise u.UnitsError("`rtol` should be dimensionless")
return actual.value, desired.value, rtol.value, atol.value
|
129c37a6211e764d0ee0173f0b05cdb162d59169cff4e3e9c2ac0f997ed64694 | import matplotlib
from matplotlib import pyplot as plt
from ..utils.decorators import wraps
MPL_VERSION = matplotlib.__version__
ROOT = "http://{server}/testing/astropy/2018-02-01T23:31:45.013149/{mpl_version}/"
IMAGE_REFERENCE_DIR = ROOT.format(server='data.astropy.org', mpl_version=MPL_VERSION[:3] + '.x')
def ignore_matplotlibrc(func):
# This is a decorator for tests that use matplotlib but not pytest-mpl
# (which already handles rcParams)
@wraps(func)
def wrapper(*args, **kwargs):
with plt.style.context({}, after_reset=True):
return func(*args, **kwargs)
return wrapper
|
764720ca5eb566100d7c4ab7a6cf4e6bd965521d1e16e6632c150dc5aa28e703 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This is retained only for backwards compatibility. Affiliated packages
should no longer import ``disable_internet`` from ``astropy.tests``. It is
now available from ``pytest_remotedata``. However, this is not the
recommended mechanism for controlling access to remote data in tests.
Instead, packages should make use of decorators provided by the
pytest_remotedata plugin: - ``@pytest.mark.remote_data`` for tests that
require remote data access - ``@pytest.mark.internet_off`` for tests that
should only run when remote data access is disabled. Remote data access for
the test suite is controlled by the ``--remote-data`` command line flag. This
is either passed to ``pytest`` directly or to the ``setup.py test`` command.
TODO: This module should eventually be removed once backwards compatibility
is no longer supported.
"""
from warnings import warn
from ..utils.exceptions import AstropyDeprecationWarning
warn("The ``disable_internet`` module is no longer provided by astropy. It "
"is now available as ``pytest_remotedata.disable_internet``. However, "
"developers are encouraged to avoid using this module directly. See "
"<https://docs.astropy.org/en/latest/whatsnew/3.0.html#pytest-plugins> "
"for more information.", AstropyDeprecationWarning)
try:
# This should only be necessary during testing, in which case the test
# package must be installed anyway.
from pytest_remotedata.disable_internet import *
except ImportError:
pass
|
5c96aae81722034e1a5cd7e3a62430c52febcedf052d6fd426b26154778928c4 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Astronomical and physics constants in SI units. See :mod:`astropy.constants`
for a complete listing of constants defined in Astropy.
"""
import numpy as np
from .constant import Constant
# ASTRONOMICAL CONSTANTS
class IAU2012(Constant):
default_reference = 'IAU 2012'
_registry = {}
_has_incompatible_units = set()
# DISTANCE
# Astronomical Unit
au = IAU2012('au', "Astronomical Unit", 1.49597870700e11, 'm', 0.0,
"IAU 2012 Resolution B2", system='si')
# Parsec
pc = IAU2012('pc', "Parsec", au.value / np.tan(np.radians(1. / 3600.)), 'm',
au.uncertainty / np.tan(np.radians(1. / 3600.)),
"Derived from au", system='si')
# Kiloparsec
kpc = IAU2012('kpc', "Kiloparsec",
1000. * au.value / np.tan(np.radians(1. / 3600.)), 'm',
1000. * au.uncertainty / np.tan(np.radians(1. / 3600.)),
"Derived from au", system='si')
# Luminosity
L_bol0 = IAU2012('L_bol0', "Luminosity for absolute bolometric magnitude 0",
3.0128e28, "W", 0.0, "IAU 2015 Resolution B 2", system='si')
# SOLAR QUANTITIES
# Solar luminosity
L_sun = IAU2012('L_sun', "Solar luminosity", 3.846e26, 'W', 0.0005e26,
"Allen's Astrophysical Quantities 4th Ed.", system='si')
# Solar mass
M_sun = IAU2012('M_sun', "Solar mass", 1.9891e30, 'kg', 0.00005e30,
"Allen's Astrophysical Quantities 4th Ed.", system='si')
# Solar radius
R_sun = IAU2012('R_sun', "Solar radius", 6.95508e8, 'm', 0.00026e8,
"Allen's Astrophysical Quantities 4th Ed.", system='si')
# OTHER SOLAR SYSTEM QUANTITIES
# Jupiter mass
M_jup = IAU2012('M_jup', "Jupiter mass", 1.8987e27, 'kg', 0.00005e27,
"Allen's Astrophysical Quantities 4th Ed.", system='si')
# Jupiter equatorial radius
R_jup = IAU2012('R_jup', "Jupiter equatorial radius", 7.1492e7, 'm',
0.00005e7, "Allen's Astrophysical Quantities 4th Ed.",
system='si')
# Earth mass
M_earth = IAU2012('M_earth', "Earth mass", 5.9742e24, 'kg', 0.00005e24,
"Allen's Astrophysical Quantities 4th Ed.", system='si')
# Earth equatorial radius
R_earth = IAU2012('R_earth', "Earth equatorial radius", 6.378136e6, 'm',
0.0000005e6, "Allen's Astrophysical Quantities 4th Ed.",
system='si')
|
d7151215de768d393c09a4b5abe77239df6b075f660ed38ad7fcfc16022c002b | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Astronomical and physics constants in SI units. See :mod:`astropy.constants`
for a complete listing of constants defined in Astropy.
"""
import numpy as np
from .constant import Constant, EMConstant
# PHYSICAL CONSTANTS
class CODATA2014(Constant):
default_reference = 'CODATA 2014'
_registry = {}
_has_incompatible_units = set()
class EMCODATA2014(CODATA2014, EMConstant):
_registry = CODATA2014._registry
h = CODATA2014('h', "Planck constant", 6.626070040e-34,
'J s', 0.000000081e-34, system='si')
hbar = CODATA2014('hbar', "Reduced Planck constant", 1.054571800e-34,
'J s', 0.000000013e-34, system='si')
k_B = CODATA2014('k_B', "Boltzmann constant", 1.38064852e-23,
'J / (K)', 0.00000079e-23, system='si')
c = CODATA2014('c', "Speed of light in vacuum", 299792458.,
'm / (s)', 0.0, system='si')
G = CODATA2014('G', "Gravitational constant", 6.67408e-11,
'm3 / (kg s2)', 0.00031e-11, system='si')
g0 = CODATA2014('g0', "Standard acceleration of gravity", 9.80665,
'm / s2', 0.0, system='si')
m_p = CODATA2014('m_p', "Proton mass", 1.672621898e-27,
'kg', 0.000000021e-27, system='si')
m_n = CODATA2014('m_n', "Neutron mass", 1.674927471e-27,
'kg', 0.000000021e-27, system='si')
m_e = CODATA2014('m_e', "Electron mass", 9.10938356e-31,
'kg', 0.00000011e-31, system='si')
u = CODATA2014('u', "Atomic mass", 1.660539040e-27,
'kg', 0.000000020e-27, system='si')
sigma_sb = CODATA2014('sigma_sb', "Stefan-Boltzmann constant", 5.670367e-8,
'W / (K4 m2)', 0.000013e-8, system='si')
e = EMCODATA2014('e', 'Electron charge', 1.6021766208e-19,
'C', 0.0000000098e-19, system='si')
eps0 = EMCODATA2014('eps0', 'Electric constant', 8.854187817e-12,
'F/m', 0.0, system='si')
N_A = CODATA2014('N_A', "Avogadro's number", 6.022140857e23,
'1 / (mol)', 0.000000074e23, system='si')
R = CODATA2014('R', "Gas constant", 8.3144598,
'J / (K mol)', 0.0000048, system='si')
Ryd = CODATA2014('Ryd', 'Rydberg constant', 10973731.568508,
'1 / (m)', 0.000065, system='si')
a0 = CODATA2014('a0', "Bohr radius", 0.52917721067e-10,
'm', 0.00000000012e-10, system='si')
muB = CODATA2014('muB', "Bohr magneton", 927.4009994e-26,
'J/T', 0.00002e-26, system='si')
alpha = CODATA2014('alpha', "Fine-structure constant", 7.2973525664e-3,
'', 0.0000000017e-3, system='si')
atm = CODATA2014('atm', "Standard atmosphere", 101325,
'Pa', 0.0, system='si')
mu0 = CODATA2014('mu0', "Magnetic constant", 4.0e-7 * np.pi, 'N/A2', 0.0,
system='si')
sigma_T = CODATA2014('sigma_T', "Thomson scattering cross-section",
0.66524587158e-28, 'm2', 0.00000000091e-28,
system='si')
b_wien = CODATA2014('b_wien', 'Wien wavelength displacement law constant',
2.8977729e-3, 'm K', 00.0000017e-3, system='si')
# cgs constants
# Only constants that cannot be converted directly from S.I. are defined here.
e_esu = EMCODATA2014(e.abbrev, e.name, e.value * c.value * 10.0,
'statC', e.uncertainty * c.value * 10.0, system='esu')
e_emu = EMCODATA2014(e.abbrev, e.name, e.value / 10, 'abC',
e.uncertainty / 10, system='emu')
e_gauss = EMCODATA2014(e.abbrev, e.name, e.value * c.value * 10.0,
'Fr', e.uncertainty * c.value * 10.0, system='gauss')
|
8422048da6508d633e96dcbc4b116a79cd1be82ac05af650dcf9749cf5c0aa6b | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Contains astronomical and physical constants for use in Astropy or other
places.
A typical use case might be::
>>> from astropy.constants import c, m_e
>>> # ... define the mass of something you want the rest energy of as m ...
>>> m = m_e
>>> E = m * c**2
>>> E.to('MeV') # doctest: +FLOAT_CMP
<Quantity 0.510998927603161 MeV>
"""
import inspect
from contextlib import contextmanager
# Hack to make circular imports with units work
try:
from .. import units
del units
except ImportError:
pass
from .constant import Constant, EMConstant # noqa
from . import si # noqa
from . import cgs # noqa
from . import codata2014, iau2015 # noqa
from . import utils as _utils
# for updating the constants module docstring
_lines = [
'The following constants are available:\n',
'========== ============== ================ =========================',
' Name Value Unit Description',
'========== ============== ================ =========================',
]
# NOTE: Update this when default changes.
_utils._set_c(codata2014, iau2015, inspect.getmodule(inspect.currentframe()),
not_in_module_only=True, doclines=_lines, set_class=True)
_lines.append(_lines[1])
if __doc__ is not None:
__doc__ += '\n'.join(_lines)
# TODO: Re-implement in a way that is more consistent with astropy.units.
# See https://github.com/astropy/astropy/pull/7008 discussions.
@contextmanager
def set_enabled_constants(modname):
"""
Context manager to temporarily set values in the ``constants``
namespace to an older version.
See :ref:`astropy-constants-prior` for usage.
Parameters
----------
modname : {'astropyconst13'}
Name of the module containing an older version.
"""
# Re-import here because these were deleted from namespace on init.
import inspect
import warnings
from . import utils as _utils
# NOTE: Update this when default changes.
if modname == 'astropyconst13':
from .astropyconst13 import codata2010 as codata
from .astropyconst13 import iau2012 as iaudata
else:
raise ValueError(
'Context manager does not currently handle {}'.format(modname))
module = inspect.getmodule(inspect.currentframe())
# Ignore warnings about "Constant xxx already has a definition..."
with warnings.catch_warnings():
warnings.simplefilter('ignore')
_utils._set_c(codata, iaudata, module,
not_in_module_only=False, set_class=True)
try:
yield
finally:
with warnings.catch_warnings():
warnings.simplefilter('ignore')
# NOTE: Update this when default changes.
_utils._set_c(codata2014, iau2015, module,
not_in_module_only=False, set_class=True)
# Clean up namespace
del inspect
del contextmanager
del _utils
del _lines
|
a98708e9b40932300529e6ff8b9ce0bbf6df894ddc9c3d9ffdeacbe62a3c7152 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Astronomical and physics constants in SI units. See :mod:`astropy.constants`
for a complete listing of constants defined in Astropy.
"""
import numpy as np
from .constant import Constant, EMConstant
# PHYSICAL CONSTANTS
class CODATA2010(Constant):
default_reference = 'CODATA 2010'
_registry = {}
_has_incompatible_units = set()
def __new__(cls, abbrev, name, value, unit, uncertainty,
reference=default_reference, system=None):
return super().__new__(
cls, abbrev, name, value, unit, uncertainty, reference, system)
class EMCODATA2010(CODATA2010, EMConstant):
_registry = CODATA2010._registry
h = CODATA2010('h', "Planck constant", 6.62606957e-34, 'J s',
0.00000029e-34, system='si')
hbar = CODATA2010('hbar', "Reduced Planck constant",
h.value * 0.5 / np.pi, 'J s',
h.uncertainty * 0.5 / np.pi,
h.reference, system='si')
k_B = CODATA2010('k_B', "Boltzmann constant", 1.3806488e-23, 'J / (K)',
0.0000013e-23, system='si')
c = CODATA2010('c', "Speed of light in vacuum", 2.99792458e8, 'm / (s)', 0.,
system='si')
G = CODATA2010('G', "Gravitational constant", 6.67384e-11, 'm3 / (kg s2)',
0.00080e-11, system='si')
g0 = CODATA2010('g0', "Standard acceleration of gravity", 9.80665, 'm / s2', 0.0,
system='si')
m_p = CODATA2010('m_p', "Proton mass", 1.672621777e-27, 'kg', 0.000000074e-27,
system='si')
m_n = CODATA2010('m_n', "Neutron mass", 1.674927351e-27, 'kg', 0.000000074e-27,
system='si')
m_e = CODATA2010('m_e', "Electron mass", 9.10938291e-31, 'kg', 0.00000040e-31,
system='si')
u = CODATA2010('u', "Atomic mass", 1.660538921e-27, 'kg', 0.000000073e-27,
system='si')
sigma_sb = CODATA2010('sigma_sb', "Stefan-Boltzmann constant", 5.670373e-8,
'W / (K4 m2)', 0.000021e-8, system='si')
e = EMCODATA2010('e', 'Electron charge', 1.602176565e-19, 'C', 0.000000035e-19,
system='si')
eps0 = EMCODATA2010('eps0', 'Electric constant', 8.854187817e-12, 'F/m', 0.0,
system='si')
N_A = CODATA2010('N_A', "Avogadro's number", 6.02214129e23, '1 / (mol)',
0.00000027e23, system='si')
R = CODATA2010('R', "Gas constant", 8.3144621, 'J / (K mol)', 0.0000075,
system='si')
Ryd = CODATA2010('Ryd', 'Rydberg constant', 10973731.568539, '1 / (m)',
0.000055, system='si')
a0 = CODATA2010('a0', "Bohr radius", 0.52917721092e-10, 'm', 0.00000000017e-10,
system='si')
muB = CODATA2010('muB', "Bohr magneton", 927.400968e-26, 'J/T', 0.00002e-26,
system='si')
alpha = CODATA2010('alpha', "Fine-structure constant", 7.2973525698e-3,
'', 0.0000000024e-3, system='si')
atm = CODATA2010('atm', "Standard atmosphere", 101325, 'Pa', 0.0,
system='si')
mu0 = CODATA2010('mu0', "Magnetic constant", 4.0e-7 * np.pi, 'N/A2', 0.0,
system='si')
sigma_T = CODATA2010('sigma_T', "Thomson scattering cross-section",
0.6652458734e-28, 'm2', 0.0000000013e-28, system='si')
b_wien = Constant('b_wien', 'Wien wavelength displacement law constant',
2.8977721e-3, 'm K', 0.0000026e-3, 'CODATA 2010', system='si')
# cgs constants
# Only constants that cannot be converted directly from S.I. are defined here.
e_esu = EMCODATA2010(e.abbrev, e.name, e.value * c.value * 10.0,
'statC', e.uncertainty * c.value * 10.0, system='esu')
e_emu = EMCODATA2010(e.abbrev, e.name, e.value / 10, 'abC',
e.uncertainty / 10, system='emu')
e_gauss = EMCODATA2010(e.abbrev, e.name, e.value * c.value * 10.0,
'Fr', e.uncertainty * c.value * 10.0, system='gauss')
|
9547dcedb4c8e705412c4dc9900c379a5ce9218ded7bc87daee2eea7c29df6e4 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Astronomical and physics constants for Astropy v1.3 and earlier.
See :mod:`astropy.constants` for a complete listing of constants
defined in Astropy.
"""
import inspect
from . import utils as _utils
from . import codata2010, iau2012
_utils._set_c(codata2010, iau2012, inspect.getmodule(inspect.currentframe()))
# Clean up namespace
del inspect
del _utils
|
8160b661c19685069d4c326fea1e9091605a79ffdc67957f4f1ffc25afb0e1bb | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Astronomical and physics constants in SI units. See :mod:`astropy.constants`
for a complete listing of constants defined in Astropy.
"""
import numpy as np
from .constant import Constant
from .codata2014 import G
# ASTRONOMICAL CONSTANTS
class IAU2015(Constant):
default_reference = 'IAU 2015'
_registry = {}
_has_incompatible_units = set()
# DISTANCE
# Astronomical Unit
au = IAU2015('au', "Astronomical Unit", 1.49597870700e11, 'm', 0.0,
"IAU 2012 Resolution B2", system='si')
# Parsec
pc = IAU2015('pc', "Parsec", au.value / np.tan(np.radians(1. / 3600.)), 'm',
au.uncertainty / np.tan(np.radians(1. / 3600.)),
"Derived from au", system='si')
# Kiloparsec
kpc = IAU2015('kpc', "Kiloparsec",
1000. * au.value / np.tan(np.radians(1. / 3600.)), 'm',
1000. * au.uncertainty / np.tan(np.radians(1. / 3600.)),
"Derived from au", system='si')
# Luminosity
L_bol0 = IAU2015('L_bol0', "Luminosity for absolute bolometric magnitude 0",
3.0128e28, "W", 0.0, "IAU 2015 Resolution B 2", system='si')
# SOLAR QUANTITIES
# Solar luminosity
L_sun = IAU2015('L_sun', "Nominal solar luminosity", 3.828e26,
'W', 0.0, "IAU 2015 Resolution B 3", system='si')
# Solar mass parameter
GM_sun = IAU2015('GM_sun', 'Nominal solar mass parameter', 1.3271244e20,
'm3 / (s2)', 0.0, "IAU 2015 Resolution B 3", system='si')
# Solar mass (derived from mass parameter and gravitational constant)
M_sun = IAU2015('M_sun', "Solar mass", GM_sun.value / G.value,
'kg', ((G.uncertainty / G.value) *
(GM_sun.value / G.value)),
"IAU 2015 Resolution B 3 + CODATA 2014", system='si')
# Solar radius
R_sun = IAU2015('R_sun', "Nominal solar radius", 6.957e8, 'm', 0.0,
"IAU 2015 Resolution B 3", system='si')
# OTHER SOLAR SYSTEM QUANTITIES
# Jupiter mass parameter
GM_jup = IAU2015('GM_jup', 'Nominal Jupiter mass parameter', 1.2668653e17,
'm3 / (s2)', 0.0, "IAU 2015 Resolution B 3", system='si')
# Jupiter mass (derived from mass parameter and gravitational constant)
M_jup = IAU2015('M_jup', "Jupiter mass", GM_jup.value / G.value,
'kg', ((G.uncertainty / G.value) *
(GM_jup.value / G.value)),
"IAU 2015 Resolution B 3 + CODATA 2014", system='si')
# Jupiter equatorial radius
R_jup = IAU2015('R_jup', "Nominal Jupiter equatorial radius", 7.1492e7,
'm', 0.0, "IAU 2015 Resolution B 3", system='si')
# Earth mass parameter
GM_earth = IAU2015('GM_earth', 'Nominal Earth mass parameter', 3.986004e14,
'm3 / (s2)', 0.0, "IAU 2015 Resolution B 3", system='si')
# Earth mass (derived from mass parameter and gravitational constant)
M_earth = IAU2015('M_earth', "Earth mass",
GM_earth.value / G.value,
'kg', ((G.uncertainty / G.value) *
(GM_earth.value / G.value)),
"IAU 2015 Resolution B 3 + CODATA 2014", system='si')
# Earth equatorial radius
R_earth = IAU2015('R_earth', "Nominal Earth equatorial radius", 6.3781e6,
'm', 0.0, "IAU 2015 Resolution B 3", system='si')
|
3c887bb764ca200aa1a037c7c5dc08a14aa209badd24b86081a8b2bd59f9e82d | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
Astronomical and physics constants for Astropy v2.0. See :mod:`astropy.constants`
for a complete listing of constants defined in Astropy.
"""
import inspect
from . import utils as _utils
from . import codata2014, iau2015
_utils._set_c(codata2014, iau2015, inspect.getmodule(inspect.currentframe()))
# Clean up namespace
del inspect
del _utils
|
23da9068839b5173829f67bfb88de75bf61fd418e7e85421f8c6d9393393c537 | # Licensed under a 3-clause BSD style license - see LICENSE.rst
"""Utility functions for ``constants`` sub-package."""
import itertools
__all__ = []
def _get_c(codata, iaudata, module, not_in_module_only=True):
"""
Generator to return a Constant object.
Parameters
----------
codata, iaudata : obj
Modules containing CODATA and IAU constants of interest.
module : obj
Namespace module of interest.
not_in_module_only : bool
If ``True``, ignore constants that are already in the
namespace of ``module``.
Returns
-------
_c : Constant
Constant object to process.
"""
from .constant import Constant
for _nm, _c in itertools.chain(sorted(vars(codata).items()),
sorted(vars(iaudata).items())):
if not isinstance(_c, Constant):
continue
elif (not not_in_module_only) or (_c.abbrev not in module.__dict__):
yield _c
def _set_c(codata, iaudata, module, not_in_module_only=True, doclines=None,
set_class=False):
"""
Set constants in a given module namespace.
Parameters
----------
codata, iaudata : obj
Modules containing CODATA and IAU constants of interest.
module : obj
Namespace module to modify with the given ``codata`` and ``iaudata``.
not_in_module_only : bool
If ``True``, constants that are already in the namespace
of ``module`` will not be modified.
doclines : list or `None`
If a list is given, this list will be modified in-place to include
documentation of modified constants. This can be used to update
docstring of ``module``.
set_class : bool
Namespace of ``module`` is populated with ``_c.__class__``
instead of just ``_c`` from :func:`_get_c`.
"""
for _c in _get_c(codata, iaudata, module,
not_in_module_only=not_in_module_only):
if set_class:
value = _c.__class__(_c.abbrev, _c.name, _c.value,
_c._unit_string, _c.uncertainty,
_c.reference)
else:
value = _c
setattr(module, _c.abbrev, value)
if doclines is not None:
doclines.append('{0:^10} {1:^14.9g} {2:^16} {3}'.format(
_c.abbrev, _c.value, _c._unit_string, _c.name))
|
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