content: # -*- coding: utf-8 -*-
  
  from __future__ import print_function
  from warnings import catch_warnings
  
  from datetime import datetime, date, timedelta, time
  
  from pandas.compat import map, zip, range, lrange, lzip, long
  from pandas import compat
  
  from numpy import nan
  from numpy.random import randn
  
  import pytest
  import numpy as np
  
  import pandas.core.common as com
  from pandas import (DataFrame, Index, Series, notnull, isnull,
                      MultiIndex, DatetimeIndex, Timestamp,
                      date_range)
  import pandas as pd
  
  from pandas._libs.tslib import iNaT
  from pandas.tseries.offsets import BDay
  from pandas.core.dtypes.common import (
      is_float_dtype,
      is_integer,
      is_scalar)
  from pandas.util.testing import (assert_almost_equal,
                                   assert_series_equal,
                                   assert_frame_equal)
  from pandas.core.indexing import IndexingError
  
  import pandas.util.testing as tm
  
  from pandas.tests.frame.common import TestData
  
  
  class TestDataFrameIndexing(TestData):
  
      def test_getitem(self):
          # Slicing
          sl = self.frame[:20]
          assert len(sl.index) == 20
  
          # Column access
          for _, series in compat.iteritems(sl):
              assert len(series.index) == 20
              assert tm.equalContents(series.index, sl.index)
  
          for key, _ in compat.iteritems(self.frame._series):
              assert self.frame[key] is not None
  
          assert 'random' not in self.frame
          with tm.assert_raises_regex(KeyError, 'random'):
              self.frame['random']
  
          df = self.frame.copy()
          df['$10'] = randn(len(df))
  
          ad = randn(len(df))
          df['@awesome_domain'] = ad
  
          with pytest.raises(KeyError):
              df.__getitem__('df["$10"]')
  
          res = df['@awesome_domain']
          tm.assert_numpy_array_equal(ad, res.values)
  
      def test_getitem_dupe_cols(self):
          df = DataFrame([[1, 2, 3], [4, 5, 6]], columns=['a', 'a', 'b'])
          try:
              df[['baf']]
          except KeyError:
              pass
          else:
              self.fail("Dataframe failed to raise KeyError")
  
      def test_get(self):
          b = self.frame.get('B')
          assert_series_equal(b, self.frame['B'])
  
          assert self.frame.get('foo') is None
          assert_series_equal(self.frame.get('foo', self.frame['B']),
                              self.frame['B'])
          # None
          # GH 5652
          for df in [DataFrame(), DataFrame(columns=list('AB')),
                     DataFrame(columns=list('AB'), index=range(3))]:
              result = df.get(None)
              assert result is None
  
      def test_getitem_iterator(self):
          idx = iter(['A', 'B', 'C'])
          result = self.frame.loc[:, idx]
          expected = self.frame.loc[:, ['A', 'B', 'C']]
          assert_frame_equal(result, expected)
  
          idx = iter(['A', 'B', 'C'])
          result = self.frame.loc[:, idx]
          expected = self.frame.loc[:, ['A', 'B', 'C']]
          assert_frame_equal(result, expected)
  
      def test_getitem_list(self):
          self.frame.columns.name = 'foo'
  
          result = self.frame[['B', 'A']]
          result2 = self.frame[Index(['B', 'A'])]
  
          expected = self.frame.loc[:, ['B', 'A']]
          expected.columns.name = 'foo'
  
          assert_frame_equal(result, expected)
          assert_frame_equal(result2, expected)
  
          assert result.columns.name == 'foo'
  
          with tm.assert_raises_regex(KeyError, 'not in index'):
              self.frame[['B', 'A', 'food']]
          with tm.assert_raises_regex(KeyError, 'not in index'):
              self.frame[Index(['B', 'A', 'foo'])]
  
          # tuples
          df = DataFrame(randn(8, 3),
                         columns=Index([('foo', 'bar'), ('baz', 'qux'),
                                        ('peek', 'aboo')], name=['sth', 'sth2']))
  
          result = df[[('foo', 'bar'), ('baz', 'qux')]]
          expected = df.iloc[:, :2]
          assert_frame_equal(result, expected)
          assert result.columns.names == ['sth', 'sth2']
  
      def test_getitem_callable(self):
          # GH 12533
          result = self.frame[lambda x: 'A']
          tm.assert_series_equal(result, self.frame.loc[:, 'A'])
  
          result = self.frame[lambda x: ['A', 'B']]
          tm.assert_frame_equal(result, self.frame.loc[:, ['A', 'B']])
  
          df = self.frame[:3]
          result = df[lambda x: [True, False, True]]
          tm.assert_frame_equal(result, self.frame.iloc[[0, 2], :])
  
      def test_setitem_list(self):
  
          self.frame['E'] = 'foo'
          data = self.frame[['A', 'B']]
          self.frame[['B', 'A']] = data
  
          assert_series_equal(self.frame['B'], data['A'], check_names=False)
          assert_series_equal(self.frame['A'], data['B'], check_names=False)
  
          with tm.assert_raises_regex(ValueError,
                                      'Columns must be same length as key'):
              data[['A']] = self.frame[['A', 'B']]
  
          with tm.assert_raises_regex(ValueError, 'Length of values '
                                      'does not match '
                                      'length of index'):
              data['A'] = range(len(data.index) - 1)
  
          df = DataFrame(0, lrange(3), ['tt1', 'tt2'], dtype=np.int_)
          df.loc[1, ['tt1', 'tt2']] = [1, 2]
  
          result = df.loc[df.index[1], ['tt1', 'tt2']]
          expected = Series([1, 2], df.columns, dtype=np.int_, name=1)
          assert_series_equal(result, expected)
  
          df['tt1'] = df['tt2'] = '0'
          df.loc[df.index[1], ['tt1', 'tt2']] = ['1', '2']
          result = df.loc[df.index[1], ['tt1', 'tt2']]
          expected = Series(['1', '2'], df.columns, name=1)
          assert_series_equal(result, expected)
  
      def test_setitem_list_not_dataframe(self):
          data = np.random.randn(len(self.frame), 2)
          self.frame[['A', 'B']] = data
          assert_almost_equal(self.frame[['A', 'B']].values, data)
  
      def test_setitem_list_of_tuples(self):
          tuples = lzip(self.frame['A'], self.frame['B'])
          self.frame['tuples'] = tuples
  
          result = self.frame['tuples']
          expected = Series(tuples, index=self.frame.index, name='tuples')
          assert_series_equal(result, expected)
  
      def test_setitem_mulit_index(self):
          # GH7655, test that assigning to a sub-frame of a frame
          # with multi-index columns aligns both rows and columns
          it = ['jim', 'joe', 'jolie'], ['first', 'last'], \
               ['left', 'center', 'right']
  
          cols = MultiIndex.from_product(it)
          index = pd.date_range('20141006', periods=20)
          vals = np.random.randint(1, 1000, (len(index), len(cols)))
          df = pd.DataFrame(vals, columns=cols, index=index)
  
          i, j = df.index.values.copy(), it[-1][:]
  
          np.random.shuffle(i)
          df['jim'] = df['jolie'].loc[i, ::-1]
          assert_frame_equal(df['jim'], df['jolie'])
  
          np.random.shuffle(j)
          df[('joe', 'first')] = df[('jolie', 'last')].loc[i, j]
          assert_frame_equal(df[('joe', 'first')], df[('jolie', 'last')])
  
          np.random.shuffle(j)
          df[('joe', 'last')] = df[('jolie', 'first')].loc[i, j]
          assert_frame_equal(df[('joe', 'last')], df[('jolie', 'first')])
  
      def test_setitem_callable(self):
          # GH 12533
          df = pd.DataFrame({'A': [1, 2, 3, 4], 'B': [5, 6, 7, 8]})
          df[lambda x: 'A'] = [11, 12, 13, 14]
  
          exp = pd.DataFrame({'A': [11, 12, 13, 14], 'B': [5, 6, 7, 8]})
          tm.assert_frame_equal(df, exp)
  
      def test_setitem_other_callable(self):
          # GH 13299
          inc = lambda x: x + 1
  
          df = pd.DataFrame([[-1, 1], [1, -1]])
          df[df > 0] = inc
  
          expected = pd.DataFrame([[-1, inc], [inc, -1]])
          tm.assert_frame_equal(df, expected)
  
      def test_getitem_boolean(self):
          # boolean indexing
          d = self.tsframe.index[10]
          indexer = self.tsframe.index > d
          indexer_obj = indexer.astype(object)
  
          subindex = self.tsframe.index[indexer]
          subframe = self.tsframe[indexer]
  
          tm.assert_index_equal(subindex, subframe.index)
          with tm.assert_raises_regex(ValueError, 'Item wrong length'):
              self.tsframe[indexer[:-1]]
  
          subframe_obj = self.tsframe[indexer_obj]
          assert_frame_equal(subframe_obj, subframe)
  
          with tm.assert_raises_regex(ValueError, 'boolean values only'):
              self.tsframe[self.tsframe]
  
          # test that Series work
          indexer_obj = Series(indexer_obj, self.tsframe.index)
  
          subframe_obj = self.tsframe[indexer_obj]
          assert_frame_equal(subframe_obj, subframe)
  
          # test that Series indexers reindex
          # we are producing a warning that since the passed boolean
          # key is not the same as the given index, we will reindex
          # not sure this is really necessary
          with tm.assert_produces_warning(UserWarning, check_stacklevel=False):
              indexer_obj = indexer_obj.reindex(self.tsframe.index[::-1])
              subframe_obj = self.tsframe[indexer_obj]
              assert_frame_equal(subframe_obj, subframe)
  
          # test df[df > 0]
          for df in [self.tsframe, self.mixed_frame,
                     self.mixed_float, self.mixed_int]:
  
              data = df._get_numeric_data()
              bif = df[df > 0]
              bifw = DataFrame(dict([(c, np.where(data[c] > 0, data[c], np.nan))
                                     for c in data.columns]),
                               index=data.index, columns=data.columns)
  
              # add back other columns to compare
              for c in df.columns:
                  if c not in bifw:
                      bifw[c] = df[c]
              bifw = bifw.reindex(columns=df.columns)
  
              assert_frame_equal(bif, bifw, check_dtype=False)
              for c in df.columns:
                  if bif[c].dtype != bifw[c].dtype:
                      assert bif[c].dtype == df[c].dtype
  
      def test_getitem_boolean_casting(self):
  
          # don't upcast if we don't need to
          df = self.tsframe.copy()
          df['E'] = 1
          df['E'] = df['E'].astype('int32')
          df['E1'] = df['E'].copy()
          df['F'] = 1
          df['F'] = df['F'].astype('int64')
          df['F1'] = df['F'].copy()
  
          casted = df[df > 0]
          result = casted.get_dtype_counts()
          expected = Series({'float64': 4, 'int32': 2, 'int64': 2})
          assert_series_equal(result, expected)
  
          # int block splitting
          df.loc[df.index[1:3], ['E1', 'F1']] = 0
          casted = df[df > 0]
          result = casted.get_dtype_counts()
          expected = Series({'float64': 6, 'int32': 1, 'int64': 1})
          assert_series_equal(result, expected)
  
          # where dtype conversions
          # GH 3733
          df = DataFrame(data=np.random.randn(100, 50))
          df = df.where(df > 0)  # create nans
          bools = df > 0
          mask = isnull(df)
          expected = bools.astype(float).mask(mask)
          result = bools.mask(mask)
          assert_frame_equal(result, expected)
  
      def test_getitem_boolean_list(self):
          df = DataFrame(np.arange(12).reshape(3, 4))
  
          def _checkit(lst):
              result = df[lst]
              expected = df.loc[df.index[lst]]
              assert_frame_equal(result, expected)
  
          _checkit([True, False, True])
          _checkit([True, True, True])
          _checkit([False, False, False])
  
      def test_getitem_boolean_iadd(self):
          arr = randn(5, 5)
  
          df = DataFrame(arr.copy(), columns=['A', 'B', 'C', 'D', 'E'])
  
          df[df < 0] += 1
          arr[arr < 0] += 1
  
          assert_almost_equal(df.values, arr)
  
      def test_boolean_index_empty_corner(self):
          # #2096
          blah = DataFrame(np.empty([0, 1]), columns=['A'],
                           index=DatetimeIndex([]))
  
          # both of these should succeed trivially
          k = np.array([], bool)
  
          blah[k]
          blah[k] = 0
  
      def test_getitem_ix_mixed_integer(self):
          df = DataFrame(np.random.randn(4, 3),
                         index=[1, 10, 'C', 'E'], columns=[1, 2, 3])
  
          result = df.iloc[:-1]
          expected = df.loc[df.index[:-1]]
          assert_frame_equal(result, expected)
  
          with catch_warnings(record=True):
              result = df.ix[[1, 10]]
              expected = df.ix[Index([1, 10], dtype=object)]
          assert_frame_equal(result, expected)
  
          # 11320
          df = pd.DataFrame({"rna": (1.5, 2.2, 3.2, 4.5),
                             -1000: [11, 21, 36, 40],
                             0: [10, 22, 43, 34],
                             1000: [0, 10, 20, 30]},
                            columns=['rna', -1000, 0, 1000])
          result = df[[1000]]
          expected = df.iloc[:, [3]]
          assert_frame_equal(result, expected)
          result = df[[-1000]]
          expected = df.iloc[:, [1]]
          assert_frame_equal(result, expected)
  
      def test_getitem_setitem_ix_negative_integers(self):
          with catch_warnings(record=True):
              result = self.frame.ix[:, -1]
          assert_series_equal(result, self.frame['D'])
  
          with catch_warnings(record=True):
              result = self.frame.ix[:, [-1]]
          assert_frame_equal(result, self.frame[['D']])
  
          with catch_warnings(record=True):
              result = self.frame.ix[:, [-1, -2]]
          assert_frame_equal(result, self.frame[['D', 'C']])
  
          with catch_warnings(record=True):
              self.frame.ix[:, [-1]] = 0
          assert (self.frame['D'] == 0).all()
  
          df = DataFrame(np.random.randn(8, 4))
          with catch_warnings(record=True):
              assert isnull(df.ix[:, [-1]].values).all()
  
          # #1942
          a = DataFrame(randn(20, 2), index=[chr(x + 65) for x in range(20)])
          with catch_warnings(record=True):
              a.ix[-1] = a.ix[-2]
  
          with catch_warnings(record=True):
              assert_series_equal(a.ix[-1], a.ix[-2], check_names=False)
              assert a.ix[-1].name == 'T'
              assert a.ix[-2].name == 'S'
  
      def test_getattr(self):
          assert_series_equal(self.frame.A, self.frame['A'])
          pytest.raises(AttributeError, getattr, self.frame,
                        'NONEXISTENT_NAME')
  
      def test_setattr_column(self):
          df = DataFrame({'foobar': 1}, index=lrange(10))
  
          df.foobar = 5
          assert (df.foobar == 5).all()
  
      def test_setitem(self):
          # not sure what else to do here
          series = self.frame['A'][::2]
          self.frame['col5'] = series
          assert 'col5' in self.frame
  
          assert len(series) == 15
          assert len(self.frame) == 30
  
          exp = np.ravel(np.column_stack((series.values, [np.nan] * 15)))
          exp = Series(exp, index=self.frame.index, name='col5')
          tm.assert_series_equal(self.frame['col5'], exp)
  
          series = self.frame['A']
          self.frame['col6'] = series
          tm.assert_series_equal(series, self.frame['col6'], check_names=False)
  
          with pytest.raises(KeyError):
              self.frame[randn(len(self.frame) + 1)] = 1
  
          # set ndarray
          arr = randn(len(self.frame))
          self.frame['col9'] = arr
          assert (self.frame['col9'] == arr).all()
  
          self.frame['col7'] = 5
          assert((self.frame['col7'] == 5).all())
  
          self.frame['col0'] = 3.14
          assert((self.frame['col0'] == 3.14).all())
  
          self.frame['col8'] = 'foo'
          assert((self.frame['col8'] == 'foo').all())
  
          # this is partially a view (e.g. some blocks are view)
          # so raise/warn
          smaller = self.frame[:2]
  
          def f():
              smaller['col10'] = ['1', '2']
          pytest.raises(com.SettingWithCopyError, f)
          assert smaller['col10'].dtype == np.object_
          assert (smaller['col10'] == ['1', '2']).all()
  
          # with a dtype
          for dtype in ['int32', 'int64', 'float32', 'float64']:
              self.frame[dtype] = np.array(arr, dtype=dtype)
              assert self.frame[dtype].dtype.name == dtype
  
          # dtype changing GH4204
          df = DataFrame([[0, 0]])
          df.iloc[0] = np.nan
          expected = DataFrame([[np.nan, np.nan]])
          assert_frame_equal(df, expected)
  
          df = DataFrame([[0, 0]])
          df.loc[0] = np.nan
          assert_frame_equal(df, expected)
  
      def test_setitem_tuple(self):
          self.frame['A', 'B'] = self.frame['A']
          assert_series_equal(self.frame['A', 'B'], self.frame[
                              'A'], check_names=False)
  
      def test_setitem_always_copy(self):
          s = self.frame['A'].copy()
          self.frame['E'] = s
  
          self.frame['E'][5:10] = nan
          assert notnull(s[5:10]).all()
  
      def test_setitem_boolean(self):
          df = self.frame.copy()
          values = self.frame.values
  
          df[df['A'] > 0] = 4
          values[values[:, 0] > 0] = 4
          assert_almost_equal(df.values, values)
  
          # test that column reindexing works
          series = df['A'] == 4
          series = series.reindex(df.index[::-1])
          df[series] = 1
          values[values[:, 0] == 4] = 1
          assert_almost_equal(df.values, values)
  
          df[df > 0] = 5
          values[values > 0] = 5
          assert_almost_equal(df.values, values)
  
          df[df == 5] = 0
          values[values == 5] = 0
          assert_almost_equal(df.values, values)
  
          # a df that needs alignment first
          df[df[:-1] < 0] = 2
          np.putmask(values[:-1], values[:-1] < 0, 2)
          assert_almost_equal(df.values, values)
  
          # indexed with same shape but rows-reversed df
          df[df[::-1] == 2] = 3
          values[values == 2] = 3
          assert_almost_equal(df.values, values)
  
          with tm.assert_raises_regex(TypeError, 'Must pass '
                                      'DataFrame with '
                                      'boolean values only'):
              df[df * 0] = 2
  
          # index with DataFrame
          mask = df > np.abs(df)
          expected = df.copy()
          df[df > np.abs(df)] = nan
          expected.values[mask.values] = nan
          assert_frame_equal(df, expected)
  
          # set from DataFrame
          expected = df.copy()
          df[df > np.abs(df)] = df * 2
          np.putmask(expected.values, mask.values, df.values * 2)
          assert_frame_equal(df, expected)
  
      def test_setitem_cast(self):
          self.frame['D'] = self.frame['D'].astype('i8')
          assert self.frame['D'].dtype == np.int64
  
          # #669, should not cast?
          # this is now set to int64, which means a replacement of the column to
          # the value dtype (and nothing to do with the existing dtype)
          self.frame['B'] = 0
          assert self.frame['B'].dtype == np.int64
  
          # cast if pass array of course
          self.frame['B'] = np.arange(len(self.frame))
          assert issubclass(self.frame['B'].dtype.type, np.integer)
  
          self.frame['foo'] = 'bar'
          self.frame['foo'] = 0
          assert self.frame['foo'].dtype == np.int64
  
          self.frame['foo'] = 'bar'
          self.frame['foo'] = 2.5
          assert self.frame['foo'].dtype == np.float64
  
          self.frame['something'] = 0
          assert self.frame['something'].dtype == np.int64
          self.frame['something'] = 2
          assert self.frame['something'].dtype == np.int64
          self.frame['something'] = 2.5
          assert self.frame['something'].dtype == np.float64
  
          # GH 7704
          # dtype conversion on setting
          df = DataFrame(np.random.rand(30, 3), columns=tuple('ABC'))
          df['event'] = np.nan
          df.loc[10, 'event'] = 'foo'
          result = df.get_dtype_counts().sort_values()
          expected = Series({'float64': 3, 'object': 1}).sort_values()
          assert_series_equal(result, expected)
  
          # Test that data type is preserved . #5782
          df = DataFrame({'one': np.arange(6, dtype=np.int8)})
          df.loc[1, 'one'] = 6
          assert df.dtypes.one == np.dtype(np.int8)
          df.one = np.int8(7)
          assert df.dtypes.one == np.dtype(np.int8)
  
      def test_setitem_boolean_column(self):
          expected = self.frame.copy()
          mask = self.frame['A'] > 0
  
          self.frame.loc[mask, 'B'] = 0
          expected.values[mask.values, 1] = 0
  
          assert_frame_equal(self.frame, expected)
  
      def test_setitem_corner(self):
          # corner case
          df = DataFrame({'B': [1., 2., 3.],
                          'C': ['a', 'b', 'c']},
                         index=np.arange(3))
          del df['B']
          df['B'] = [1., 2., 3.]
          assert 'B' in df
          assert len(df.columns) == 2
  
          df['A'] = 'beginning'
          df['E'] = 'foo'
          df['D'] = 'bar'
          df[datetime.now()] = 'date'
          df[datetime.now()] = 5.
  
          # what to do when empty frame with index
          dm = DataFrame(index=self.frame.index)
          dm['A'] = 'foo'
          dm['B'] = 'bar'
          assert len(dm.columns) == 2
          assert dm.values.dtype == np.object_
  
          # upcast
          dm['C'] = 1
          assert dm['C'].dtype == np.int64
  
          dm['E'] = 1.
          assert dm['E'].dtype == np.float64
  
          # set existing column
          dm['A'] = 'bar'
          assert 'bar' == dm['A'][0]
  
          dm = DataFrame(index=np.arange(3))
          dm['A'] = 1
          dm['foo'] = 'bar'
          del dm['foo']
          dm['foo'] = 'bar'
          assert dm['foo'].dtype == np.object_
  
          dm['coercable'] = ['1', '2', '3']
          assert dm['coercable'].dtype == np.object_
  
      def test_setitem_corner2(self):
          data = {"title": ['foobar', 'bar', 'foobar'] + ['foobar'] * 17,
                  "cruft": np.random.random(20)}
  
          df = DataFrame(data)
          ix = df[df['title'] == 'bar'].index
  
          df.loc[ix, ['title']] = 'foobar'
          df.loc[ix, ['cruft']] = 0
  
          assert df.loc[1, 'title'] == 'foobar'
          assert df.loc[1, 'cruft'] == 0
  
      def test_setitem_ambig(self):
          # Difficulties with mixed-type data
          from decimal import Decimal
  
          # Created as float type
          dm = DataFrame(index=lrange(3), columns=lrange(3))
  
          coercable_series = Series([Decimal(1) for _ in range(3)],
                                    index=lrange(3))
          uncoercable_series = Series(['foo', 'bzr', 'baz'], index=lrange(3))
  
          dm[0] = np.ones(3)
          assert len(dm.columns) == 3
  
          dm[1] = coercable_series
          assert len(dm.columns) == 3
  
          dm[2] = uncoercable_series
          assert len(dm.columns) == 3
          assert dm[2].dtype == np.object_
  
      def test_setitem_clear_caches(self):
          # see gh-304
          df = DataFrame({'x': [1.1, 2.1, 3.1, 4.1], 'y': [5.1, 6.1, 7.1, 8.1]},
                         index=[0, 1, 2, 3])
          df.insert(2, 'z', np.nan)
  
          # cache it
          foo = df['z']
          df.loc[df.index[2:], 'z'] = 42
  
          expected = Series([np.nan, np.nan, 42, 42], index=df.index, name='z')
  
          assert df['z'] is not foo
          tm.assert_series_equal(df['z'], expected)
  
      def test_setitem_None(self):
          # GH #766
          self.frame[None] = self.frame['A']
          assert_series_equal(
              self.frame.iloc[:, -1], self.frame['A'], check_names=False)
          assert_series_equal(self.frame.loc[:, None], self.frame[
                              'A'], check_names=False)
          assert_series_equal(self.frame[None], self.frame[
                              'A'], check_names=False)
          repr(self.frame)
  
      def test_setitem_empty(self):
          # GH 9596
          df = pd.DataFrame({'a': ['1', '2', '3'],
                             'b': ['11', '22', '33'],
                             'c': ['111', '222', '333']})
  
          result = df.copy()
          result.loc[result.b.isnull(), 'a'] = result.a
          assert_frame_equal(result, df)
  
      def test_setitem_empty_frame_with_boolean(self):
          # Test for issue #10126
  
          for dtype in ('float', 'int64'):
              for df in [
                      pd.DataFrame(dtype=dtype),
                      pd.DataFrame(dtype=dtype, index=[1]),
                      pd.DataFrame(dtype=dtype, columns=['A']),
              ]:
                  df2 = df.copy()
                  df[df > df2] = 47
                  assert_frame_equal(df, df2)
  
      def test_getitem_empty_frame_with_boolean(self):
          # Test for issue #11859
  
          df = pd.DataFrame()
          df2 = df[df > 0]
          assert_frame_equal(df, df2)
  
      def test_delitem_corner(self):
          f = self.frame.copy()
          del f['D']
          assert len(f.columns) == 3
          pytest.raises(KeyError, f.__delitem__, 'D')
          del f['B']
          assert len(f.columns) == 2
  
      def test_getitem_fancy_2d(self):
          f = self.frame
  
          with catch_warnings(record=True):
              assert_frame_equal(f.ix[:, ['B', 'A']],
                                 f.reindex(columns=['B', 'A']))
  
          subidx = self.frame.index[[5, 4, 1]]
          with catch_warnings(record=True):
              assert_frame_equal(f.ix[subidx, ['B', 'A']],
                                 f.reindex(index=subidx, columns=['B', 'A']))
  
          # slicing rows, etc.
          with catch_warnings(record=True):
              assert_frame_equal(f.ix[5:10], f[5:10])
              assert_frame_equal(f.ix[5:10, :], f[5:10])
              assert_frame_equal(f.ix[:5, ['A', 'B']],
                                 f.reindex(index=f.index[:5],
                                           columns=['A', 'B']))
  
          # slice rows with labels, inclusive!
          with catch_warnings(record=True):
              expected = f.ix[5:11]
              result = f.ix[f.index[5]:f.index[10]]
          assert_frame_equal(expected, result)
  
          # slice columns
          with catch_warnings(record=True):
              assert_frame_equal(f.ix[:, :2], f.reindex(columns=['A', 'B']))
  
          # get view
          with catch_warnings(record=True):
              exp = f.copy()
              f.ix[5:10].values[:] = 5
              exp.values[5:10] = 5
              assert_frame_equal(f, exp)
  
          with catch_warnings(record=True):
              pytest.raises(ValueError, f.ix.__getitem__, f > 0.5)
  
      def test_slice_floats(self):
          index = [52195.504153, 52196.303147, 52198.369883]
          df = DataFrame(np.random.rand(3, 2), index=index)
  
          s1 = df.loc[52195.1:52196.5]
          assert len(s1) == 2
  
          s1 = df.loc[52195.1:52196.6]
          assert len(s1) == 2
  
          s1 = df.loc[52195.1:52198.9]
          assert len(s1) == 3
  
      def test_getitem_fancy_slice_integers_step(self):
          df = DataFrame(np.random.randn(10, 5))
  
          # this is OK
          result = df.iloc[:8:2]  # noqa
          df.iloc[:8:2] = np.nan
          assert isnull(df.iloc[:8:2]).values.all()
  
      def test_getitem_setitem_integer_slice_keyerrors(self):
          df = DataFrame(np.random.randn(10, 5), index=lrange(0, 20, 2))
  
          # this is OK
          cp = df.copy()
          cp.iloc[4:10] = 0
          assert (cp.iloc[4:10] == 0).values.all()
  
          # so is this
          cp = df.copy()
          cp.iloc[3:11] = 0
          assert (cp.iloc[3:11] == 0).values.all()
  
          result = df.iloc[2:6]
          result2 = df.loc[3:11]
          expected = df.reindex([4, 6, 8, 10])
  
          assert_frame_equal(result, expected)
          assert_frame_equal(result2, expected)
  
          # non-monotonic, raise KeyError
          df2 = df.iloc[lrange(5) + lrange(5, 10)[::-1]]
          pytest.raises(KeyError, df2.loc.__getitem__, slice(3, 11))
          pytest.raises(KeyError, df2.loc.__setitem__, slice(3, 11), 0)
  
      def test_setitem_fancy_2d(self):
  
          # case 1
          frame = self.frame.copy()
          expected = frame.copy()
  
          with catch_warnings(record=True):
              frame.ix[:, ['B', 'A']] = 1
          expected['B'] = 1.
          expected['A'] = 1.
          assert_frame_equal(frame, expected)
  
          # case 2
          frame = self.frame.copy()
          frame2 = self.frame.copy()
  
          expected = frame.copy()
  
          subidx = self.frame.index[[5, 4, 1]]
          values = randn(3, 2)
  
          with catch_warnings(record=True):
              frame.ix[subidx, ['B', 'A']] = values
              frame2.ix[[5, 4, 1], ['B', 'A']] = values
  
              expected['B'].ix[subidx] = values[:, 0]
              expected['A'].ix[subidx] = values[:, 1]
  
          assert_frame_equal(frame, expected)
          assert_frame_equal(frame2, expected)
  
          # case 3: slicing rows, etc.
          frame = self.frame.copy()
  
          with catch_warnings(record=True):
              expected1 = self.frame.copy()
              frame.ix[5:10] = 1.
              expected1.values[5:10] = 1.
          assert_frame_equal(frame, expected1)
  
          with catch_warnings(record=True):
              expected2 = self.frame.copy()
              arr = randn(5, len(frame.columns))
              frame.ix[5:10] = arr
              expected2.values[5:10] = arr
          assert_frame_equal(frame, expected2)
  
          # case 4
          with catch_warnings(record=True):
              frame = self.frame.copy()
              frame.ix[5:10, :] = 1.
              assert_frame_equal(frame, expected1)
              frame.ix[5:10, :] = arr
          assert_frame_equal(frame, expected2)
  
          # case 5
          with catch_warnings(record=True):
              frame = self.frame.copy()
              frame2 = self.frame.copy()
  
              expected = self.frame.copy()
              values = randn(5, 2)
  
              frame.ix[:5, ['A', 'B']] = values
              expected['A'][:5] = values[:, 0]
              expected['B'][:5] = values[:, 1]
          assert_frame_equal(frame, expected)
  
          with catch_warnings(record=True):
              frame2.ix[:5, [0, 1]] = values
          assert_frame_equal(frame2, expected)
  
          # case 6: slice rows with labels, inclusive!
          with catch_warnings(record=True):
              frame = self.frame.copy()
              expected = self.frame.copy()
  
              frame.ix[frame.index[5]:frame.index[10]] = 5.
              expected.values[5:11] = 5
          assert_frame_equal(frame, expected)
  
          # case 7: slice columns
          with catch_warnings(record=True):
              frame = self.frame.copy()
              frame2 = self.frame.copy()
              expected = self.frame.copy()
  
              # slice indices
              frame.ix[:, 1:3] = 4.
              expected.values[:, 1:3] = 4.
              assert_frame_equal(frame, expected)
  
              # slice with labels
              frame.ix[:, 'B':'C'] = 4.
              assert_frame_equal(frame, expected)
  
          # new corner case of boolean slicing / setting
          frame = DataFrame(lzip([2, 3, 9, 6, 7], [np.nan] * 5),
                            columns=['a', 'b'])
          lst = [100]
          lst.extend([np.nan] * 4)
          expected = DataFrame(lzip([100, 3, 9, 6, 7], lst),
                               columns=['a', 'b'])
          frame[frame['a'] == 2] = 100
          assert_frame_equal(frame, expected)
  
      def test_fancy_getitem_slice_mixed(self):
          sliced = self.mixed_frame.iloc[:, -3:]
          assert sliced['D'].dtype == np.float64
  
          # get view with single block
          # setting it triggers setting with copy
          sliced = self.frame.iloc[:, -3:]
  
          def f():
              sliced['C'] = 4.
          pytest.raises(com.SettingWithCopyError, f)
          assert (self.frame['C'] == 4).all()
  
      def test_fancy_setitem_int_labels(self):
          # integer index defers to label-based indexing
  
          df = DataFrame(np.random.randn(10, 5), index=np.arange(0, 20, 2))
  
          with catch_warnings(record=True):
              tmp = df.copy()
              exp = df.copy()
              tmp.ix[[0, 2, 4]] = 5
              exp.values[:3] = 5
          assert_frame_equal(tmp, exp)
  
          with catch_warnings(record=True):
              tmp = df.copy()
              exp = df.copy()
              tmp.ix[6] = 5
              exp.values[3] = 5
          assert_frame_equal(tmp, exp)
  
          with catch_warnings(record=True):
              tmp = df.copy()
              exp = df.copy()
              tmp.ix[:, 2] = 5
  
          # tmp correctly sets the dtype
          # so match the exp way
          exp[2] = 5
          assert_frame_equal(tmp, exp)
  
      def test_fancy_getitem_int_labels(self):
          df = DataFrame(np.random.randn(10, 5), index=np.arange(0, 20, 2))
  
          with catch_warnings(record=True):
              result = df.ix[[4, 2, 0], [2, 0]]
              expected = df.reindex(index=[4, 2, 0], columns=[2, 0])
          assert_frame_equal(result, expected)
  
          with catch_warnings(record=True):
              result = df.ix[[4, 2, 0]]
              expected = df.reindex(index=[4, 2, 0])
          assert_frame_equal(result, expected)
  
          with catch_warnings(record=True):
              result = df.ix[4]
              expected = df.xs(4)
          assert_series_equal(result, expected)
  
          with catch_warnings(record=True):
              result = df.ix[:, 3]
              expected = df[3]
          assert_series_equal(result, expected)
  
      def test_fancy_index_int_labels_exceptions(self):
          df = DataFrame(np.random.randn(10, 5), index=np.arange(0, 20, 2))
  
          with catch_warnings(record=True):
  
              # labels that aren't contained
              pytest.raises(KeyError, df.ix.__setitem__,
                            ([0, 1, 2], [2, 3, 4]), 5)
  
              # try to set indices not contained in frame
              pytest.raises(KeyError, self.frame.ix.__setitem__,
                            ['foo', 'bar', 'baz'], 1)
              pytest.raises(KeyError, self.frame.ix.__setitem__,
                            (slice(None, None), ['E']), 1)
  
              # partial setting now allows this GH2578
              # pytest.raises(KeyError, self.frame.ix.__setitem__,
              #               (slice(None, None), 'E'), 1)
  
      def test_setitem_fancy_mixed_2d(self):
  
          with catch_warnings(record=True):
              self.mixed_frame.ix[:5, ['C', 'B', 'A']] = 5
              result = self.mixed_frame.ix[:5, ['C', 'B', 'A']]
              assert (result.values == 5).all()
  
              self.mixed_frame.ix[5] = np.nan
              assert isnull(self.mixed_frame.ix[5]).all()
  
              self.mixed_frame.ix[5] = self.mixed_frame.ix[6]
              assert_series_equal(self.mixed_frame.ix[5], self.mixed_frame.ix[6],
                                  check_names=False)
  
          # #1432
          with catch_warnings(record=True):
              df = DataFrame({1: [1., 2., 3.],
                              2: [3, 4, 5]})
              assert df._is_mixed_type
  
              df.ix[1] = [5, 10]
  
              expected = DataFrame({1: [1., 5., 3.],
                                    2: [3, 10, 5]})
  
              assert_frame_equal(df, expected)
  
      def test_ix_align(self):
          b = Series(randn(10), name=0).sort_values()
          df_orig = DataFrame(randn(10, 4))
          df = df_orig.copy()
  
          with catch_warnings(record=True):
              df.ix[:, 0] = b
              assert_series_equal(df.ix[:, 0].reindex(b.index), b)
  
          with catch_warnings(record=True):
              dft = df_orig.T
              dft.ix[0, :] = b
              assert_series_equal(dft.ix[0, :].reindex(b.index), b)
  
          with catch_warnings(record=True):
              df = df_orig.copy()
              df.ix[:5, 0] = b
              s = df.ix[:5, 0]
              assert_series_equal(s, b.reindex(s.index))
  
          with catch_warnings(record=True):
              dft = df_orig.T
              dft.ix[0, :5] = b
              s = dft.ix[0, :5]
              assert_series_equal(s, b.reindex(s.index))
  
          with catch_warnings(record=True):
              df = df_orig.copy()
              idx = [0, 1, 3, 5]
              df.ix[idx, 0] = b
              s = df.ix[idx, 0]
              assert_series_equal(s, b.reindex(s.index))
  
          with catch_warnings(record=True):
              dft = df_orig.T
              dft.ix[0, idx] = b
              s = dft.ix[0, idx]
              assert_series_equal(s, b.reindex(s.index))
  
      def test_ix_frame_align(self):
          b = DataFrame(np.random.randn(3, 4))
          df_orig = DataFrame(randn(10, 4))
          df = df_orig.copy()
  
          with catch_warnings(record=True):
              df.ix[:3] = b
              out = b.ix[:3]
              assert_frame_equal(out, b)
  
          b.sort_index(inplace=True)
  
          with catch_warnings(record=True):
              df = df_orig.copy()
              df.ix[[0, 1, 2]] = b
              out = df.ix[[0, 1, 2]].reindex(b.index)
              assert_frame_equal(out, b)
  
          with catch_warnings(record=True):
              df = df_orig.copy()
              df.ix[:3] = b
              out = df.ix[:3]
              assert_frame_equal(out, b.reindex(out.index))
  
      def test_getitem_setitem_non_ix_labels(self):
          df = tm.makeTimeDataFrame()
  
          start, end = df.index[[5, 10]]
  
          result = df.loc[start:end]
          result2 = df[start:end]
          expected = df[5:11]
          assert_frame_equal(result, expected)
          assert_frame_equal(result2, expected)
  
          result = df.copy()
          result.loc[start:end] = 0
          result2 = df.copy()
          result2[start:end] = 0
          expected = df.copy()
          expected[5:11] = 0
          assert_frame_equal(result, expected)
          assert_frame_equal(result2, expected)
  
      def test_ix_multi_take(self):
          df = DataFrame(np.random.randn(3, 2))
          rs = df.loc[df.index == 0, :]
          xp = df.reindex([0])
          assert_frame_equal(rs, xp)
  
          """ #1321
          df = DataFrame(np.random.randn(3, 2))
          rs = df.loc[df.index==0, df.columns==1]
          xp = df.reindex([0], [1])
          assert_frame_equal(rs, xp)
          """
  
      def test_ix_multi_take_nonint_index(self):
          df = DataFrame(np.random.randn(3, 2), index=['x', 'y', 'z'],
                         columns=['a', 'b'])
          with catch_warnings(record=True):
              rs = df.ix[[0], [0]]
          xp = df.reindex(['x'], columns=['a'])
          assert_frame_equal(rs, xp)
  
      def test_ix_multi_take_multiindex(self):
          df = DataFrame(np.random.randn(3, 2), index=['x', 'y', 'z'],
                         columns=[['a', 'b'], ['1', '2']])
          with catch_warnings(record=True):
              rs = df.ix[[0], [0]]
          xp = df.reindex(['x'], columns=[('a', '1')])
          assert_frame_equal(rs, xp)
  
      def test_ix_dup(self):
          idx = Index(['a', 'a', 'b', 'c', 'd', 'd'])
          df = DataFrame(np.random.randn(len(idx), 3), idx)
  
          with catch_warnings(record=True):
              sub = df.ix[:'d']
              assert_frame_equal(sub, df)
  
          with catch_warnings(record=True):
              sub = df.ix['a':'c']
              assert_frame_equal(sub, df.ix[0:4])
  
          with catch_warnings(record=True):
              sub = df.ix['b':'d']
              assert_frame_equal(sub, df.ix[2:])
  
      def test_getitem_fancy_1d(self):
          f = self.frame
  
          # return self if no slicing...for now
          with catch_warnings(record=True):
              assert f.ix[:, :] is f
  
          # low dimensional slice
          with catch_warnings(record=True):
              xs1 = f.ix[2, ['C', 'B', 'A']]
          xs2 = f.xs(f.index[2]).reindex(['C', 'B', 'A'])
          tm.assert_series_equal(xs1, xs2)
  
          with catch_warnings(record=True):
              ts1 = f.ix[5:10, 2]
          ts2 = f[f.columns[2]][5:10]
          tm.assert_series_equal(ts1, ts2)
  
          # positional xs
          with catch_warnings(record=True):
              xs1 = f.ix[0]
          xs2 = f.xs(f.index[0])
          tm.assert_series_equal(xs1, xs2)
  
          with catch_warnings(record=True):
              xs1 = f.ix[f.index[5]]
          xs2 = f.xs(f.index[5])
          tm.assert_series_equal(xs1, xs2)
  
          # single column
          with catch_warnings(record=True):
              assert_series_equal(f.ix[:, 'A'], f['A'])
  
          # return view
          with catch_warnings(record=True):
              exp = f.copy()
              exp.values[5] = 4
              f.ix[5][:] = 4
          tm.assert_frame_equal(exp, f)
  
          with catch_warnings(record=True):
              exp.values[:, 1] = 6
              f.ix[:, 1][:] = 6
          tm.assert_frame_equal(exp, f)
  
          # slice of mixed-frame
          with catch_warnings(record=True):
              xs = self.mixed_frame.ix[5]
          exp = self.mixed_frame.xs(self.mixed_frame.index[5])
          tm.assert_series_equal(xs, exp)
  
      def test_setitem_fancy_1d(self):
  
          # case 1: set cross-section for indices
          frame = self.frame.copy()
          expected = self.frame.copy()
  
          with catch_warnings(record=True):
              frame.ix[2, ['C', 'B', 'A']] = [1., 2., 3.]
          expected['C'][2] = 1.
          expected['B'][2] = 2.
          expected['A'][2] = 3.
          assert_frame_equal(frame, expected)
  
          with catch_warnings(record=True):
              frame2 = self.frame.copy()
              frame2.ix[2, [3, 2, 1]] = [1., 2., 3.]
          assert_frame_equal(frame, expected)
  
          # case 2, set a section of a column
          frame = self.frame.copy()
          expected = self.frame.copy()
  
          with catch_warnings(record=True):
              vals = randn(5)
              expected.values[5:10, 2] = vals
              frame.ix[5:10, 2] = vals
          assert_frame_equal(frame, expected)
  
          with catch_warnings(record=True):
              frame2 = self.frame.copy()
              frame2.ix[5:10, 'B'] = vals
          assert_frame_equal(frame, expected)
  
          # case 3: full xs
          frame = self.frame.copy()
          expected = self.frame.copy()
  
          with catch_warnings(record=True):
              frame.ix[4] = 5.
              expected.values[4] = 5.
          assert_frame_equal(frame, expected)
  
          with catch_warnings(record=True):
              frame.ix[frame.index[4]] = 6.
              expected.values[4] = 6.
          assert_frame_equal(frame, expected)
  
          # single column
          frame = self.frame.copy()
          expected = self.frame.copy()
  
          with catch_warnings(record=True):
              frame.ix[:, 'A'] = 7.
              expected['A'] = 7.
          assert_frame_equal(frame, expected)
  
      def test_getitem_fancy_scalar(self):
          f = self.frame
          ix = f.loc
  
          # individual value
          for col in f.columns:
              ts = f[col]
              for idx in f.index[::5]:
                  assert ix[idx, col] == ts[idx]
  
      def test_setitem_fancy_scalar(self):
          f = self.frame
          expected = self.frame.copy()
          ix = f.loc
  
          # individual value
          for j, col in enumerate(f.columns):
              ts = f[col]  # noqa
              for idx in f.index[::5]:
                  i = f.index.get_loc(idx)
                  val = randn()
                  expected.values[i, j] = val
  
                  ix[idx, col] = val
                  assert_frame_equal(f, expected)
  
      def test_getitem_fancy_boolean(self):
          f = self.frame
          ix = f.loc
  
          expected = f.reindex(columns=['B', 'D'])
          result = ix[:, [False, True, False, True]]
          assert_frame_equal(result, expected)
  
          expected = f.reindex(index=f.index[5:10], columns=['B', 'D'])
          result = ix[f.index[5:10], [False, True, False, True]]
          assert_frame_equal(result, expected)
  
          boolvec = f.index > f.index[7]
          expected = f.reindex(index=f.index[boolvec])
          result = ix[boolvec]
          assert_frame_equal(result, expected)
          result = ix[boolvec, :]
          assert_frame_equal(result, expected)
  
          result = ix[boolvec, f.columns[2:]]
          expected = f.reindex(index=f.index[boolvec],
                               columns=['C', 'D'])
          assert_frame_equal(result, expected)
  
      def test_setitem_fancy_boolean(self):
          # from 2d, set with booleans
          frame = self.frame.copy()
          expected = self.frame.copy()
  
          mask = frame['A'] > 0
          frame.loc[mask] = 0.
          expected.values[mask.values] = 0.
          assert_frame_equal(frame, expected)
  
          frame = self.frame.copy()
          expected = self.frame.copy()
          frame.loc[mask, ['A', 'B']] = 0.
          expected.values[mask.values, :2] = 0.
          assert_frame_equal(frame, expected)
  
      def test_getitem_fancy_ints(self):
          result = self.frame.iloc[[1, 4, 7]]
          expected = self.frame.loc[self.frame.index[[1, 4, 7]]]
          assert_frame_equal(result, expected)
  
          result = self.frame.iloc[:, [2, 0, 1]]
          expected = self.frame.loc[:, self.frame.columns[[2, 0, 1]]]
          assert_frame_equal(result, expected)
  
      def test_getitem_setitem_fancy_exceptions(self):
          ix = self.frame.iloc
          with tm.assert_raises_regex(IndexingError, 'Too many indexers'):
              ix[:, :, :]
  
          with pytest.raises(IndexingError):
              ix[:, :, :] = 1
  
      def test_getitem_setitem_boolean_misaligned(self):
          # boolean index misaligned labels
          mask = self.frame['A'][::-1] > 1
  
          result = self.frame.loc[mask]
          expected = self.frame.loc[mask[::-1]]
          assert_frame_equal(result, expected)
  
          cp = self.frame.copy()
          expected = self.frame.copy()
          cp.loc[mask] = 0
          expected.loc[mask] = 0
          assert_frame_equal(cp, expected)
  
      def test_getitem_setitem_boolean_multi(self):
          df = DataFrame(np.random.randn(3, 2))
  
          # get
          k1 = np.array([True, False, True])
          k2 = np.array([False, True])
          result = df.loc[k1, k2]
          expected = df.loc[[0, 2], [1]]
          assert_frame_equal(result, expected)
  
          expected = df.copy()
          df.loc[np.array([True, False, True]),
                 np.array([False, True])] = 5
          expected.loc[[0, 2], [1]] = 5
          assert_frame_equal(df, expected)
  
      def test_getitem_setitem_float_labels(self):
          index = Index([1.5, 2, 3, 4, 5])
          df = DataFrame(np.random.randn(5, 5), index=index)
  
          result = df.loc[1.5:4]
          expected = df.reindex([1.5, 2, 3, 4])
          assert_frame_equal(result, expected)
          assert len(result) == 4
  
          result = df.loc[4:5]
          expected = df.reindex([4, 5])  # reindex with int
          assert_frame_equal(result, expected, check_index_type=False)
          assert len(result) == 2
  
          result = df.loc[4:5]
          expected = df.reindex([4.0, 5.0])  # reindex with float
          assert_frame_equal(result, expected)
          assert len(result) == 2
  
          # loc_float changes this to work properly
          result = df.loc[1:2]
          expected = df.iloc[0:2]
          assert_frame_equal(result, expected)
  
          df.loc[1:2] = 0
          result = df[1:2]
          assert (result == 0).all().all()
  
          # #2727
          index = Index([1.0, 2.5, 3.5, 4.5, 5.0])
          df = DataFrame(np.random.randn(5, 5), index=index)
  
          # positional slicing only via iloc!
          pytest.raises(TypeError, lambda: df.iloc[1.0:5])
  
          result = df.iloc[4:5]
          expected = df.reindex([5.0])
          assert_frame_equal(result, expected)
          assert len(result) == 1
  
          cp = df.copy()
  
          def f():
              cp.iloc[1.0:5] = 0
          pytest.raises(TypeError, f)
  
          def f():
              result = cp.iloc[1.0:5] == 0  # noqa
  
          pytest.raises(TypeError, f)
          assert result.values.all()
          assert (cp.iloc[0:1] == df.iloc[0:1]).values.all()
  
          cp = df.copy()
          cp.iloc[4:5] = 0
          assert (cp.iloc[4:5] == 0).values.all()
          assert (cp.iloc[0:4] == df.iloc[0:4]).values.all()
  
          # float slicing
          result = df.loc[1.0:5]
          expected = df
          assert_frame_equal(result, expected)
          assert len(result) == 5
  
          result = df.loc[1.1:5]
          expected = df.reindex([2.5, 3.5, 4.5, 5.0])
          assert_frame_equal(result, expected)
          assert len(result) == 4
  
          result = df.loc[4.51:5]
          expected = df.reindex([5.0])
          assert_frame_equal(result, expected)
          assert len(result) == 1
  
          result = df.loc[1.0:5.0]
          expected = df.reindex([1.0, 2.5, 3.5, 4.5, 5.0])
          assert_frame_equal(result, expected)
          assert len(result) == 5
  
          cp = df.copy()
          cp.loc[1.0:5.0] = 0
          result = cp.loc[1.0:5.0]
          assert (result == 0).values.all()
  
      def test_setitem_single_column_mixed(self):
          df = DataFrame(randn(5, 3), index=['a', 'b', 'c', 'd', 'e'],
                         columns=['foo', 'bar', 'baz'])
          df['str'] = 'qux'
          df.loc[df.index[::2], 'str'] = nan
          expected = np.array([nan, 'qux', nan, 'qux', nan], dtype=object)
          assert_almost_equal(df['str'].values, expected)
  
      def test_setitem_single_column_mixed_datetime(self):
          df = DataFrame(randn(5, 3), index=['a', 'b', 'c', 'd', 'e'],
                         columns=['foo', 'bar', 'baz'])
  
          df['timestamp'] = Timestamp('20010102')
  
          # check our dtypes
          result = df.get_dtype_counts()
          expected = Series({'float64': 3, 'datetime64[ns]': 1})
          assert_series_equal(result, expected)
  
          # set an allowable datetime64 type
          df.loc['b', 'timestamp'] = iNaT
          assert isnull(df.loc['b', 'timestamp'])
  
          # allow this syntax
          df.loc['c', 'timestamp'] = nan
          assert isnull(df.loc['c', 'timestamp'])
  
          # allow this syntax
          df.loc['d', :] = nan
          assert not isnull(df.loc['c', :]).all()
  
          # as of GH 3216 this will now work!
          # try to set with a list like item
          # pytest.raises(
          #    Exception, df.loc.__setitem__, ('d', 'timestamp'), [nan])
  
      def test_setitem_frame(self):
          piece = self.frame.loc[self.frame.index[:2], ['A', 'B']]
          self.frame.loc[self.frame.index[-2]:, ['A', 'B']] = piece.values
          result = self.frame.loc[self.frame.index[-2:], ['A', 'B']].values
          expected = piece.values
          assert_almost_equal(result, expected)
  
          # GH 3216
  
          # already aligned
          f = self.mixed_frame.copy()
          piece = DataFrame([[1., 2.], [3., 4.]],
                            index=f.index[0:2], columns=['A', 'B'])
          key = (slice(None, 2), ['A', 'B'])
          f.loc[key] = piece
          assert_almost_equal(f.loc[f.index[0:2], ['A', 'B']].values,
                              piece.values)
  
          # rows unaligned
          f = self.mixed_frame.copy()
          piece = DataFrame([[1., 2.], [3., 4.], [5., 6.], [7., 8.]],
                            index=list(f.index[0:2]) + ['foo', 'bar'],
                            columns=['A', 'B'])
          key = (slice(None, 2), ['A', 'B'])
          f.loc[key] = piece
          assert_almost_equal(f.loc[f.index[0:2:], ['A', 'B']].values,
                              piece.values[0:2])
  
          # key is unaligned with values
          f = self.mixed_frame.copy()
          piece = f.loc[f.index[:2], ['A']]
          piece.index = f.index[-2:]
          key = (slice(-2, None), ['A', 'B'])
          f.loc[key] = piece
          piece['B'] = np.nan
          assert_almost_equal(f.loc[f.index[-2:], ['A', 'B']].values,
                              piece.values)
  
          # ndarray
          f = self.mixed_frame.copy()
          piece = self.mixed_frame.loc[f.index[:2], ['A', 'B']]
          key = (slice(-2, None), ['A', 'B'])
          f.loc[key] = piece.values
          assert_almost_equal(f.loc[f.index[-2:], ['A', 'B']].values,
                              piece.values)
  
          # needs upcasting
          df = DataFrame([[1, 2, 'foo'], [3, 4, 'bar']], columns=['A', 'B', 'C'])
          df2 = df.copy()
          df2.loc[:, ['A', 'B']] = df.loc[:, ['A', 'B']] + 0.5
          expected = df.reindex(columns=['A', 'B'])
          expected += 0.5
          expected['C'] = df['C']
          assert_frame_equal(df2, expected)
  
      def test_setitem_frame_align(self):
          piece = self.frame.loc[self.frame.index[:2], ['A', 'B']]
          piece.index = self.frame.index[-2:]
          piece.columns = ['A', 'B']
          self.frame.loc[self.frame.index[-2:], ['A', 'B']] = piece
          result = self.frame.loc[self.frame.index[-2:], ['A', 'B']].values
          expected = piece.values
          assert_almost_equal(result, expected)
  
      def test_getitem_setitem_ix_duplicates(self):
          # #1201
          df = DataFrame(np.random.randn(5, 3),
                         index=['foo', 'foo', 'bar', 'baz', 'bar'])
  
          result = df.loc['foo']
          expected = df[:2]
          assert_frame_equal(result, expected)
  
          result = df.loc['bar']
          expected = df.iloc[[2, 4]]
          assert_frame_equal(result, expected)
  
          result = df.loc['baz']
          expected = df.iloc[3]
          assert_series_equal(result, expected)
  
      def test_getitem_ix_boolean_duplicates_multiple(self):
          # #1201
          df = DataFrame(np.random.randn(5, 3),
                         index=['foo', 'foo', 'bar', 'baz', 'bar'])
  
          result = df.loc[['bar']]
          exp = df.iloc[[2, 4]]
          assert_frame_equal(result, exp)
  
          result = df.loc[df[1] > 0]
          exp = df[df[1] > 0]
          assert_frame_equal(result, exp)
  
          result = df.loc[df[0] > 0]
          exp = df[df[0] > 0]
          assert_frame_equal(result, exp)
  
      def test_getitem_setitem_ix_bool_keyerror(self):
          # #2199
          df = DataFrame({'a': [1, 2, 3]})
  
          pytest.raises(KeyError, df.loc.__getitem__, False)
          pytest.raises(KeyError, df.loc.__getitem__, True)
  
          pytest.raises(KeyError, df.loc.__setitem__, False, 0)
          pytest.raises(KeyError, df.loc.__setitem__, True, 0)
  
      def test_getitem_list_duplicates(self):
          # #1943
          df = DataFrame(np.random.randn(4, 4), columns=list('AABC'))
          df.columns.name = 'foo'
  
          result = df[['B', 'C']]
          assert result.columns.name == 'foo'
  
          expected = df.iloc[:, 2:]
          assert_frame_equal(result, expected)
  
      def test_get_value(self):
          for idx in self.frame.index:
              for col in self.frame.columns:
                  result = self.frame.get_value(idx, col)
                  expected = self.frame[col][idx]
                  assert result == expected
  
      def test_lookup(self):
          def alt(df, rows, cols, dtype):
              result = []
              for r, c in zip(rows, cols):
                  result.append(df.get_value(r, c))
              return np.array(result, dtype=dtype)
  
          def testit(df):
              rows = list(df.index) * len(df.columns)
              cols = list(df.columns) * len(df.index)
              result = df.lookup(rows, cols)
              expected = alt(df, rows, cols, dtype=np.object_)
              tm.assert_almost_equal(result, expected, check_dtype=False)
  
          testit(self.mixed_frame)
          testit(self.frame)
  
          df = DataFrame({'label': ['a', 'b', 'a', 'c'],
                          'mask_a': [True, True, False, True],
                          'mask_b': [True, False, False, False],
                          'mask_c': [False, True, False, True]})
          df['mask'] = df.lookup(df.index, 'mask_' + df['label'])
          exp_mask = alt(df, df.index, 'mask_' + df['label'], dtype=np.bool_)
          tm.assert_series_equal(df['mask'], pd.Series(exp_mask, name='mask'))
          assert df['mask'].dtype == np.bool_
  
          with pytest.raises(KeyError):
              self.frame.lookup(['xyz'], ['A'])
  
          with pytest.raises(KeyError):
              self.frame.lookup([self.frame.index[0]], ['xyz'])
  
          with tm.assert_raises_regex(ValueError, 'same size'):
              self.frame.lookup(['a', 'b', 'c'], ['a'])
  
      def test_set_value(self):
          for idx in self.frame.index:
              for col in self.frame.columns:
                  self.frame.set_value(idx, col, 1)
                  assert self.frame[col][idx] == 1
  
      def test_set_value_resize(self):
  
          res = self.frame.set_value('foobar', 'B', 0)
          assert res is self.frame
          assert res.index[-1] == 'foobar'
          assert res.get_value('foobar', 'B') == 0
  
          self.frame.loc['foobar', 'qux'] = 0
          assert self.frame.get_value('foobar', 'qux') == 0
  
          res = self.frame.copy()
          res3 = res.set_value('foobar', 'baz', 'sam')
          assert res3['baz'].dtype == np.object_
  
          res = self.frame.copy()
          res3 = res.set_value('foobar', 'baz', True)
          assert res3['baz'].dtype == np.object_
  
          res = self.frame.copy()
          res3 = res.set_value('foobar', 'baz', 5)
          assert is_float_dtype(res3['baz'])
          assert isnull(res3['baz'].drop(['foobar'])).all()
          pytest.raises(ValueError, res3.set_value, 'foobar', 'baz', 'sam')
  
      def test_set_value_with_index_dtype_change(self):
          df_orig = DataFrame(randn(3, 3), index=lrange(3), columns=list('ABC'))
  
          # this is actually ambiguous as the 2 is interpreted as a positional
          # so column is not created
          df = df_orig.copy()
          df.set_value('C', 2, 1.0)
          assert list(df.index) == list(df_orig.index) + ['C']
          # assert list(df.columns) == list(df_orig.columns) + [2]
  
          df = df_orig.copy()
          df.loc['C', 2] = 1.0
          assert list(df.index) == list(df_orig.index) + ['C']
          # assert list(df.columns) == list(df_orig.columns) + [2]
  
          # create both new
          df = df_orig.copy()
          df.set_value('C', 'D', 1.0)
          assert list(df.index) == list(df_orig.index) + ['C']
          assert list(df.columns) == list(df_orig.columns) + ['D']
  
          df = df_orig.copy()
          df.loc['C', 'D'] = 1.0
          assert list(df.index) == list(df_orig.index) + ['C']
          assert list(df.columns) == list(df_orig.columns) + ['D']
  
      def test_get_set_value_no_partial_indexing(self):
          # partial w/ MultiIndex raise exception
          index = MultiIndex.from_tuples([(0, 1), (0, 2), (1, 1), (1, 2)])
          df = DataFrame(index=index, columns=lrange(4))
          pytest.raises(KeyError, df.get_value, 0, 1)
          # pytest.raises(KeyError, df.set_value, 0, 1, 0)
  
      def test_single_element_ix_dont_upcast(self):
          self.frame['E'] = 1
          assert issubclass(self.frame['E'].dtype.type, (int, np.integer))
  
          with catch_warnings(record=True):
              result = self.frame.ix[self.frame.index[5], 'E']
              assert is_integer(result)
  
          result = self.frame.loc[self.frame.index[5], 'E']
          assert is_integer(result)
  
          # GH 11617
          df = pd.DataFrame(dict(a=[1.23]))
          df["b"] = 666
  
          with catch_warnings(record=True):
              result = df.ix[0, "b"]
          assert is_integer(result)
          result = df.loc[0, "b"]
          assert is_integer(result)
  
          expected = Series([666], [0], name='b')
          with catch_warnings(record=True):
              result = df.ix[[0], "b"]
          assert_series_equal(result, expected)
          result = df.loc[[0], "b"]
          assert_series_equal(result, expected)
  
      def test_iloc_row(self):
          df = DataFrame(np.random.randn(10, 4), index=lrange(0, 20, 2))
  
          result = df.iloc[1]
          exp = df.loc[2]
          assert_series_equal(result, exp)
  
          result = df.iloc[2]
          exp = df.loc[4]
          assert_series_equal(result, exp)
  
          # slice
          result = df.iloc[slice(4, 8)]
          expected = df.loc[8:14]
          assert_frame_equal(result, expected)
  
          # verify slice is view
          # setting it makes it raise/warn
          def f():
              result[2] = 0.
          pytest.raises(com.SettingWithCopyError, f)
          exp_col = df[2].copy()
          exp_col[4:8] = 0.
          assert_series_equal(df[2], exp_col)
  
          # list of integers
          result = df.iloc[[1, 2, 4, 6]]
          expected = df.reindex(df.index[[1, 2, 4, 6]])
          assert_frame_equal(result, expected)
  
      def test_iloc_col(self):
  
          df = DataFrame(np.random.randn(4, 10), columns=lrange(0, 20, 2))
  
          result = df.iloc[:, 1]
          exp = df.loc[:, 2]
          assert_series_equal(result, exp)
  
          result = df.iloc[:, 2]
          exp = df.loc[:, 4]
          assert_series_equal(result, exp)
  
          # slice
          result = df.iloc[:, slice(4, 8)]
          expected = df.loc[:, 8:14]
          assert_frame_equal(result, expected)
  
          # verify slice is view
          # and that we are setting a copy
          def f():
              result[8] = 0.
          pytest.raises(com.SettingWithCopyError, f)
          assert (df[8] == 0).all()
  
          # list of integers
          result = df.iloc[:, [1, 2, 4, 6]]
          expected = df.reindex(columns=df.columns[[1, 2, 4, 6]])
          assert_frame_equal(result, expected)
  
      def test_iloc_duplicates(self):
  
          df = DataFrame(np.random.rand(3, 3), columns=list('ABC'),
                         index=list('aab'))
  
          result = df.iloc[0]
          with catch_warnings(record=True):
              result2 = df.ix[0]
          assert isinstance(result, Series)
          assert_almost_equal(result.values, df.values[0])
          assert_series_equal(result, result2)
  
          with catch_warnings(record=True):
              result = df.T.iloc[:, 0]
              result2 = df.T.ix[:, 0]
          assert isinstance(result, Series)
          assert_almost_equal(result.values, df.values[0])
          assert_series_equal(result, result2)
  
          # multiindex
          df = DataFrame(np.random.randn(3, 3),
                         columns=[['i', 'i', 'j'], ['A', 'A', 'B']],
                         index=[['i', 'i', 'j'], ['X', 'X', 'Y']])
  
          with catch_warnings(record=True):
              rs = df.iloc[0]
              xp = df.ix[0]
          assert_series_equal(rs, xp)
  
          with catch_warnings(record=True):
              rs = df.iloc[:, 0]
              xp = df.T.ix[0]
          assert_series_equal(rs, xp)
  
          with catch_warnings(record=True):
              rs = df.iloc[:, [0]]
              xp = df.ix[:, [0]]
          assert_frame_equal(rs, xp)
  
          # #2259
          df = DataFrame([[1, 2, 3], [4, 5, 6]], columns=[1, 1, 2])
          result = df.iloc[:, [0]]
          expected = df.take([0], axis=1)
          assert_frame_equal(result, expected)
  
      def test_iloc_sparse_propegate_fill_value(self):
          from pandas.core.sparse.api import SparseDataFrame
          df = SparseDataFrame({'A': [999, 1]}, default_fill_value=999)
          assert len(df['A'].sp_values) == len(df.iloc[:, 0].sp_values)
  
      def test_iat(self):
  
          for i, row in enumerate(self.frame.index):
              for j, col in enumerate(self.frame.columns):
                  result = self.frame.iat[i, j]
                  expected = self.frame.at[row, col]
                  assert result == expected
  
      def test_nested_exception(self):
          # Ignore the strange way of triggering the problem
          # (which may get fixed), it's just a way to trigger
          # the issue or reraising an outer exception without
          # a named argument
          df = DataFrame({"a": [1, 2, 3], "b": [4, 5, 6],
                          "c": [7, 8, 9]}).set_index(["a", "b"])
          l = list(df.index)
          l[0] = ["a", "b"]
          df.index = l
  
          try:
              repr(df)
          except Exception as e:
              assert type(e) != UnboundLocalError
  
      def test_reindex_methods(self):
          df = pd.DataFrame({'x': list(range(5))})
          target = np.array([-0.1, 0.9, 1.1, 1.5])
  
          for method, expected_values in [('nearest', [0, 1, 1, 2]),
                                          ('pad', [np.nan, 0, 1, 1]),
                                          ('backfill', [0, 1, 2, 2])]:
              expected = pd.DataFrame({'x': expected_values}, index=target)
              actual = df.reindex(target, method=method)
              assert_frame_equal(expected, actual)
  
              actual = df.reindex_like(df, method=method, tolerance=0)
              assert_frame_equal(df, actual)
  
              actual = df.reindex(target, method=method, tolerance=1)
              assert_frame_equal(expected, actual)
  
              e2 = expected[::-1]
              actual = df.reindex(target[::-1], method=method)
              assert_frame_equal(e2, actual)
  
              new_order = [3, 0, 2, 1]
              e2 = expected.iloc[new_order]
              actual = df.reindex(target[new_order], method=method)
              assert_frame_equal(e2, actual)
  
              switched_method = ('pad' if method == 'backfill'
                                 else 'backfill' if method == 'pad'
                                 else method)
              actual = df[::-1].reindex(target, method=switched_method)
              assert_frame_equal(expected, actual)
  
          expected = pd.DataFrame({'x': [0, 1, 1, np.nan]}, index=target)
          actual = df.reindex(target, method='nearest', tolerance=0.2)
          assert_frame_equal(expected, actual)
  
      def test_reindex_frame_add_nat(self):
          rng = date_range('1/1/2000 00:00:00', periods=10, freq='10s')
          df = DataFrame({'A': np.random.randn(len(rng)), 'B': rng})
  
          result = df.reindex(lrange(15))
          assert np.issubdtype(result['B'].dtype, np.dtype('M8[ns]'))
  
          mask = com.isnull(result)['B']
          assert mask[-5:].all()
          assert not mask[:-5].any()
  
      def test_set_dataframe_column_ns_dtype(self):
          x = DataFrame([datetime.now(), datetime.now()])
          assert x[0].dtype == np.dtype('M8[ns]')
  
      def test_non_monotonic_reindex_methods(self):
          dr = pd.date_range('2013-08-01', periods=6, freq='B')
          data = np.random.randn(6, 1)
          df = pd.DataFrame(data, index=dr, columns=list('A'))
          df_rev = pd.DataFrame(data, index=dr[[3, 4, 5] + [0, 1, 2]],
                                columns=list('A'))
          # index is not monotonic increasing or decreasing
          pytest.raises(ValueError, df_rev.reindex, df.index, method='pad')
          pytest.raises(ValueError, df_rev.reindex, df.index, method='ffill')
          pytest.raises(ValueError, df_rev.reindex, df.index, method='bfill')
          pytest.raises(ValueError, df_rev.reindex, df.index, method='nearest')
  
      def test_reindex_level(self):
          from itertools import permutations
          icol = ['jim', 'joe', 'jolie']
  
          def verify_first_level(df, level, idx, check_index_type=True):
              f = lambda val: np.nonzero(df[level] == val)[0]
              i = np.concatenate(list(map(f, idx)))
              left = df.set_index(icol).reindex(idx, level=level)
              right = df.iloc[i].set_index(icol)
              assert_frame_equal(left, right, check_index_type=check_index_type)
  
          def verify(df, level, idx, indexer, check_index_type=True):
              left = df.set_index(icol).reindex(idx, level=level)
              right = df.iloc[indexer].set_index(icol)
              assert_frame_equal(left, right, check_index_type=check_index_type)
  
          df = pd.DataFrame({'jim': list('B' * 4 + 'A' * 2 + 'C' * 3),
                             'joe': list('abcdeabcd')[::-1],
                             'jolie': [10, 20, 30] * 3,
                             'joline': np.random.randint(0, 1000, 9)})
  
          target = [['C', 'B', 'A'], ['F', 'C', 'A', 'D'], ['A'],
                    ['A', 'B', 'C'], ['C', 'A', 'B'], ['C', 'B'], ['C', 'A'],
                    ['A', 'B'], ['B', 'A', 'C']]
  
          for idx in target:
              verify_first_level(df, 'jim', idx)
  
          # reindex by these causes different MultiIndex levels
          for idx in [['D', 'F'], ['A', 'C', 'B']]:
              verify_first_level(df, 'jim', idx, check_index_type=False)
  
          verify(df, 'joe', list('abcde'), [3, 2, 1, 0, 5, 4, 8, 7, 6])
          verify(df, 'joe', list('abcd'), [3, 2, 1, 0, 5, 8, 7, 6])
          verify(df, 'joe', list('abc'), [3, 2, 1, 8, 7, 6])
          verify(df, 'joe', list('eca'), [1, 3, 4, 6, 8])
          verify(df, 'joe', list('edc'), [0, 1, 4, 5, 6])
          verify(df, 'joe', list('eadbc'), [3, 0, 2, 1, 4, 5, 8, 7, 6])
          verify(df, 'joe', list('edwq'), [0, 4, 5])
          verify(df, 'joe', list('wq'), [], check_index_type=False)
  
          df = DataFrame({'jim': ['mid'] * 5 + ['btm'] * 8 + ['top'] * 7,
                          'joe': ['3rd'] * 2 + ['1st'] * 3 + ['2nd'] * 3 +
                          ['1st'] * 2 + ['3rd'] * 3 + ['1st'] * 2 +
                          ['3rd'] * 3 + ['2nd'] * 2,
                          # this needs to be jointly unique with jim and joe or
                          # reindexing will fail ~1.5% of the time, this works
                          # out to needing unique groups of same size as joe
                          'jolie': np.concatenate([
                              np.random.choice(1000, x, replace=False)
                              for x in [2, 3, 3, 2, 3, 2, 3, 2]]),
                          'joline': np.random.randn(20).round(3) * 10})
  
          for idx in permutations(df['jim'].unique()):
              for i in range(3):
                  verify_first_level(df, 'jim', idx[:i + 1])
  
          i = [2, 3, 4, 0, 1, 8, 9, 5, 6, 7, 10,
               11, 12, 13, 14, 18, 19, 15, 16, 17]
          verify(df, 'joe', ['1st', '2nd', '3rd'], i)
  
          i = [0, 1, 2, 3, 4, 10, 11, 12, 5, 6,
               7, 8, 9, 15, 16, 17, 18, 19, 13, 14]
          verify(df, 'joe', ['3rd', '2nd', '1st'], i)
  
          i = [0, 1, 5, 6, 7, 10, 11, 12, 18, 19, 15, 16, 17]
          verify(df, 'joe', ['2nd', '3rd'], i)
  
          i = [0, 1, 2, 3, 4, 10, 11, 12, 8, 9, 15, 16, 17, 13, 14]
          verify(df, 'joe', ['3rd', '1st'], i)
  
      def test_getitem_ix_float_duplicates(self):
          df = pd.DataFrame(np.random.randn(3, 3),
                            index=[0.1, 0.2, 0.2], columns=list('abc'))
          expect = df.iloc[1:]
          assert_frame_equal(df.loc[0.2], expect)
          with catch_warnings(record=True):
              assert_frame_equal(df.ix[0.2], expect)
  
          expect = df.iloc[1:, 0]
          assert_series_equal(df.loc[0.2, 'a'], expect)
  
          df.index = [1, 0.2, 0.2]
          expect = df.iloc[1:]
          assert_frame_equal(df.loc[0.2], expect)
          with catch_warnings(record=True):
              assert_frame_equal(df.ix[0.2], expect)
  
          expect = df.iloc[1:, 0]
          assert_series_equal(df.loc[0.2, 'a'], expect)
  
          df = pd.DataFrame(np.random.randn(4, 3),
                            index=[1, 0.2, 0.2, 1], columns=list('abc'))
          expect = df.iloc[1:-1]
          assert_frame_equal(df.loc[0.2], expect)
          with catch_warnings(record=True):
              assert_frame_equal(df.ix[0.2], expect)
  
          expect = df.iloc[1:-1, 0]
          assert_series_equal(df.loc[0.2, 'a'], expect)
  
          df.index = [0.1, 0.2, 2, 0.2]
          expect = df.iloc[[1, -1]]
          assert_frame_equal(df.loc[0.2], expect)
          with catch_warnings(record=True):
              assert_frame_equal(df.ix[0.2], expect)
  
          expect = df.iloc[[1, -1], 0]
          assert_series_equal(df.loc[0.2, 'a'], expect)
  
      def test_setitem_with_sparse_value(self):
          # GH8131
          df = pd.DataFrame({'c_1': ['a', 'b', 'c'], 'n_1': [1., 2., 3.]})
          sp_series = pd.Series([0, 0, 1]).to_sparse(fill_value=0)
          df['new_column'] = sp_series
          assert_series_equal(df['new_column'], sp_series, check_names=False)
  
      def test_setitem_with_unaligned_sparse_value(self):
          df = pd.DataFrame({'c_1': ['a', 'b', 'c'], 'n_1': [1., 2., 3.]})
          sp_series = (pd.Series([0, 0, 1], index=[2, 1, 0])
                       .to_sparse(fill_value=0))
          df['new_column'] = sp_series
          exp = pd.Series([1, 0, 0], name='new_column')
          assert_series_equal(df['new_column'], exp)
  
      def test_setitem_with_unaligned_tz_aware_datetime_column(self):
          # GH 12981
          # Assignment of unaligned offset-aware datetime series.
          # Make sure timezone isn't lost
          column = pd.Series(pd.date_range('2015-01-01', periods=3, tz='utc'),
                             name='dates')
          df = pd.DataFrame({'dates': column})
          df['dates'] = column[[1, 0, 2]]
          assert_series_equal(df['dates'], column)
  
          df = pd.DataFrame({'dates': column})
          df.loc[[0, 1, 2], 'dates'] = column[[1, 0, 2]]
          assert_series_equal(df['dates'], column)
  
      def test_setitem_datetime_coercion(self):
          # gh-1048
          df = pd.DataFrame({'c': [pd.Timestamp('2010-10-01')] * 3})
          df.loc[0:1, 'c'] = np.datetime64('2008-08-08')
          assert pd.Timestamp('2008-08-08') == df.loc[0, 'c']
          assert pd.Timestamp('2008-08-08') == df.loc[1, 'c']
          df.loc[2, 'c'] = date(2005, 5, 5)
          assert pd.Timestamp('2005-05-05') == df.loc[2, 'c']
  
      def test_setitem_datetimelike_with_inference(self):
          # GH 7592
          # assignment of timedeltas with NaT
  
          one_hour = timedelta(hours=1)
          df = DataFrame(index=date_range('20130101', periods=4))
          df['A'] = np.array([1 * one_hour] * 4, dtype='m8[ns]')
          df.loc[:, 'B'] = np.array([2 * one_hour] * 4, dtype='m8[ns]')
          df.loc[:3, 'C'] = np.array([3 * one_hour] * 3, dtype='m8[ns]')
          df.loc[:, 'D'] = np.array([4 * one_hour] * 4, dtype='m8[ns]')
          df.loc[df.index[:3], 'E'] = np.array([5 * one_hour] * 3,
                                               dtype='m8[ns]')
          df['F'] = np.timedelta64('NaT')
          df.loc[df.index[:-1], 'F'] = np.array([6 * one_hour] * 3,
                                                dtype='m8[ns]')
          df.loc[df.index[-3]:, 'G'] = date_range('20130101', periods=3)
          df['H'] = np.datetime64('NaT')
          result = df.dtypes
          expected = Series([np.dtype('timedelta64[ns]')] * 6 +
                            [np.dtype('datetime64[ns]')] * 2,
                            index=list('ABCDEFGH'))
          assert_series_equal(result, expected)
  
      def test_at_time_between_time_datetimeindex(self):
          index = date_range("2012-01-01", "2012-01-05", freq='30min')
          df = DataFrame(randn(len(index), 5), index=index)
          akey = time(12, 0, 0)
          bkey = slice(time(13, 0, 0), time(14, 0, 0))
          ainds = [24, 72, 120, 168]
          binds = [26, 27, 28, 74, 75, 76, 122, 123, 124, 170, 171, 172]
  
          result = df.at_time(akey)
          expected = df.loc[akey]
          expected2 = df.iloc[ainds]
          assert_frame_equal(result, expected)
          assert_frame_equal(result, expected2)
          assert len(result) == 4
  
          result = df.between_time(bkey.start, bkey.stop)
          expected = df.loc[bkey]
          expected2 = df.iloc[binds]
          assert_frame_equal(result, expected)
          assert_frame_equal(result, expected2)
          assert len(result) == 12
  
          result = df.copy()
          result.loc[akey] = 0
          result = result.loc[akey]
          expected = df.loc[akey].copy()
          expected.loc[:] = 0
          assert_frame_equal(result, expected)
  
          result = df.copy()
          result.loc[akey] = 0
          result.loc[akey] = df.iloc[ainds]
          assert_frame_equal(result, df)
  
          result = df.copy()
          result.loc[bkey] = 0
          result = result.loc[bkey]
          expected = df.loc[bkey].copy()
          expected.loc[:] = 0
          assert_frame_equal(result, expected)
  
          result = df.copy()
          result.loc[bkey] = 0
          result.loc[bkey] = df.iloc[binds]
          assert_frame_equal(result, df)
  
      def test_xs(self):
          idx = self.frame.index[5]
          xs = self.frame.xs(idx)
          for item, value in compat.iteritems(xs):
              if np.isnan(value):
                  assert np.isnan(self.frame[item][idx])
              else:
                  assert value == self.frame[item][idx]
  
          # mixed-type xs
          test_data = {
              'A': {'1': 1, '2': 2},
              'B': {'1': '1', '2': '2', '3': '3'},
          }
          frame = DataFrame(test_data)
          xs = frame.xs('1')
          assert xs.dtype == np.object_
          assert xs['A'] == 1
          assert xs['B'] == '1'
  
          with pytest.raises(KeyError):
              self.tsframe.xs(self.tsframe.index[0] - BDay())
  
          # xs get column
          series = self.frame.xs('A', axis=1)
          expected = self.frame['A']
          assert_series_equal(series, expected)
  
          # view is returned if possible
          series = self.frame.xs('A', axis=1)
          series[:] = 5
          assert (expected == 5).all()
  
      def test_xs_corner(self):
          # pathological mixed-type reordering case
          df = DataFrame(index=[0])
          df['A'] = 1.
          df['B'] = 'foo'
          df['C'] = 2.
          df['D'] = 'bar'
          df['E'] = 3.
  
          xs = df.xs(0)
          exp = pd.Series([1., 'foo', 2., 'bar', 3.],
                          index=list('ABCDE'), name=0)
          tm.assert_series_equal(xs, exp)
  
          # no columns but Index(dtype=object)
          df = DataFrame(index=['a', 'b', 'c'])
          result = df.xs('a')
          expected = Series([], name='a', index=pd.Index([], dtype=object))
          assert_series_equal(result, expected)
  
      def test_xs_duplicates(self):
          df = DataFrame(randn(5, 2), index=['b', 'b', 'c', 'b', 'a'])
  
          cross = df.xs('c')
          exp = df.iloc[2]
          assert_series_equal(cross, exp)
  
      def test_xs_keep_level(self):
          df = (DataFrame({'day': {0: 'sat', 1: 'sun'},
                           'flavour': {0: 'strawberry', 1: 'strawberry'},
                           'sales': {0: 10, 1: 12},
                           'year': {0: 2008, 1: 2008}})
                .set_index(['year', 'flavour', 'day']))
          result = df.xs('sat', level='day', drop_level=False)
          expected = df[:1]
          assert_frame_equal(result, expected)
  
          result = df.xs([2008, 'sat'], level=['year', 'day'], drop_level=False)
          assert_frame_equal(result, expected)
  
      def test_xs_view(self):
          # in 0.14 this will return a view if possible a copy otherwise, but
          # this is numpy dependent
  
          dm = DataFrame(np.arange(20.).reshape(4, 5),
                         index=lrange(4), columns=lrange(5))
  
          dm.xs(2)[:] = 10
          assert (dm.xs(2) == 10).all()
  
      def test_index_namedtuple(self):
          from collections import namedtuple
          IndexType = namedtuple("IndexType", ["a", "b"])
          idx1 = IndexType("foo", "bar")
          idx2 = IndexType("baz", "bof")
          index = Index([idx1, idx2],
                        name="composite_index", tupleize_cols=False)
          df = DataFrame([(1, 2), (3, 4)], index=index, columns=["A", "B"])
  
          with catch_warnings(record=True):
              result = df.ix[IndexType("foo", "bar")]["A"]
          assert result == 1
  
          result = df.loc[IndexType("foo", "bar")]["A"]
          assert result == 1
  
      def test_boolean_indexing(self):
          idx = lrange(3)
          cols = ['A', 'B', 'C']
          df1 = DataFrame(index=idx, columns=cols,
                          data=np.array([[0.0, 0.5, 1.0],
                                         [1.5, 2.0, 2.5],
                                         [3.0, 3.5, 4.0]],
                                        dtype=float))
          df2 = DataFrame(index=idx, columns=cols,
                          data=np.ones((len(idx), len(cols))))
  
          expected = DataFrame(index=idx, columns=cols,
                               data=np.array([[0.0, 0.5, 1.0],
                                              [1.5, 2.0, -1],
                                              [-1, -1, -1]], dtype=float))
  
          df1[df1 > 2.0 * df2] = -1
          assert_frame_equal(df1, expected)
          with tm.assert_raises_regex(ValueError, 'Item wrong length'):
              df1[df1.index[:-1] > 2] = -1
  
      def test_boolean_indexing_mixed(self):
          df = DataFrame({
              long(0): {35: np.nan, 40: np.nan, 43: np.nan,
                        49: np.nan, 50: np.nan},
              long(1): {35: np.nan,
                        40: 0.32632316859446198,
                        43: np.nan,
                        49: 0.32632316859446198,
                        50: 0.39114724480578139},
              long(2): {35: np.nan, 40: np.nan, 43: 0.29012581014105987,
                        49: np.nan, 50: np.nan},
              long(3): {35: np.nan, 40: np.nan, 43: np.nan, 49: np.nan,
                        50: np.nan},
              long(4): {35: 0.34215328467153283, 40: np.nan, 43: np.nan,
                        49: np.nan, 50: np.nan},
              'y': {35: 0, 40: 0, 43: 0, 49: 0, 50: 1}})
  
          # mixed int/float ok
          df2 = df.copy()
          df2[df2 > 0.3] = 1
          expected = df.copy()
          expected.loc[40, 1] = 1
          expected.loc[49, 1] = 1
          expected.loc[50, 1] = 1
          expected.loc[35, 4] = 1
          assert_frame_equal(df2, expected)
  
          df['foo'] = 'test'
          with tm.assert_raises_regex(TypeError, 'boolean setting '
                                      'on mixed-type'):
              df[df > 0.3] = 1
  
      def test_where(self):
          default_frame = DataFrame(np.random.randn(5, 3),
                                    columns=['A', 'B', 'C'])
  
          def _safe_add(df):
              # only add to the numeric items
              def is_ok(s):
                  return (issubclass(s.dtype.type, (np.integer, np.floating)) and
                          s.dtype != 'uint8')
  
              return DataFrame(dict([(c, s + 1) if is_ok(s) else (c, s)
                                     for c, s in compat.iteritems(df)]))
  
          def _check_get(df, cond, check_dtypes=True):
              other1 = _safe_add(df)
              rs = df.where(cond, other1)
              rs2 = df.where(cond.values, other1)
              for k, v in rs.iteritems():
                  exp = Series(
                      np.where(cond[k], df[k], other1[k]), index=v.index)
                  assert_series_equal(v, exp, check_names=False)
              assert_frame_equal(rs, rs2)
  
              # dtypes
              if check_dtypes:
                  assert (rs.dtypes == df.dtypes).all()
  
          # check getting
          for df in [default_frame, self.mixed_frame,
                     self.mixed_float, self.mixed_int]:
              cond = df > 0
              _check_get(df, cond)
  
          # upcasting case (GH # 2794)
          df = DataFrame(dict([(c, Series([1] * 3, dtype=c))
                               for c in ['int64', 'int32',
                                         'float32', 'float64']]))
          df.iloc[1, :] = 0
          result = df.where(df >= 0).get_dtype_counts()
  
          # when we don't preserve boolean casts
          #
          # expected = Series({ 'float32' : 1, 'float64' : 3 })
  
          expected = Series({'float32': 1, 'float64': 1, 'int32': 1, 'int64': 1})
          assert_series_equal(result, expected)
  
          # aligning
          def _check_align(df, cond, other, check_dtypes=True):
              rs = df.where(cond, other)
              for i, k in enumerate(rs.columns):
                  result = rs[k]
                  d = df[k].values
                  c = cond[k].reindex(df[k].index).fillna(False).values
  
                  if is_scalar(other):
                      o = other
                  else:
                      if isinstance(other, np.ndarray):
                          o = Series(other[:, i], index=result.index).values
                      else:
                          o = other[k].values
  
                  new_values = d if c.all() else np.where(c, d, o)
                  expected = Series(new_values, index=result.index, name=k)
  
                  # since we can't always have the correct numpy dtype
                  # as numpy doesn't know how to downcast, don't check
                  assert_series_equal(result, expected, check_dtype=False)
  
              # dtypes
              # can't check dtype when other is an ndarray
  
              if check_dtypes and not isinstance(other, np.ndarray):
                  assert (rs.dtypes == df.dtypes).all()
  
          for df in [self.mixed_frame, self.mixed_float, self.mixed_int]:
  
              # other is a frame
              cond = (df > 0)[1:]
              _check_align(df, cond, _safe_add(df))
  
              # check other is ndarray
              cond = df > 0
              _check_align(df, cond, (_safe_add(df).values))
  
              # integers are upcast, so don't check the dtypes
              cond = df > 0
              check_dtypes = all([not issubclass(s.type, np.integer)
                                  for s in df.dtypes])
              _check_align(df, cond, np.nan, check_dtypes=check_dtypes)
  
          # invalid conditions
          df = default_frame
          err1 = (df + 1).values[0:2, :]
          pytest.raises(ValueError, df.where, cond, err1)
  
          err2 = cond.iloc[:2, :].values
          other1 = _safe_add(df)
          pytest.raises(ValueError, df.where, err2, other1)
  
          pytest.raises(ValueError, df.mask, True)
          pytest.raises(ValueError, df.mask, 0)
  
          # where inplace
          def _check_set(df, cond, check_dtypes=True):
              dfi = df.copy()
              econd = cond.reindex_like(df).fillna(True)
              expected = dfi.mask(~econd)
  
              dfi.where(cond, np.nan, inplace=True)
              assert_frame_equal(dfi, expected)
  
              # dtypes (and confirm upcasts)x
              if check_dtypes:
                  for k, v in compat.iteritems(df.dtypes):
                      if issubclass(v.type, np.integer) and not cond[k].all():
                          v = np.dtype('float64')
                      assert dfi[k].dtype == v
  
          for df in [default_frame, self.mixed_frame, self.mixed_float,
                     self.mixed_int]:
  
              cond = df > 0
              _check_set(df, cond)
  
              cond = df >= 0
              _check_set(df, cond)
  
              # aligining
              cond = (df >= 0)[1:]
              _check_set(df, cond)
  
          # GH 10218
          # test DataFrame.where with Series slicing
          df = DataFrame({'a': range(3), 'b': range(4, 7)})
          result = df.where(df['a'] == 1)
          expected = df[df['a'] == 1].reindex(df.index)
          assert_frame_equal(result, expected)
  
      def test_where_array_like(self):
          # see gh-15414
          klasses = [list, tuple, np.array]
  
          df = DataFrame({'a': [1, 2, 3]})
          cond = [[False], [True], [True]]
          expected = DataFrame({'a': [np.nan, 2, 3]})
  
          for klass in klasses:
              result = df.where(klass(cond))
              assert_frame_equal(result, expected)
  
          df['b'] = 2
          expected['b'] = [2, np.nan, 2]
          cond = [[False, True], [True, False], [True, True]]
  
          for klass in klasses:
              result = df.where(klass(cond))
              assert_frame_equal(result, expected)
  
      def test_where_invalid_input(self):
          # see gh-15414: only boolean arrays accepted
          df = DataFrame({'a': [1, 2, 3]})
          msg = "Boolean array expected for the condition"
  
          conds = [
              [[1], [0], [1]],
              Series([[2], [5], [7]]),
              DataFrame({'a': [2, 5, 7]}),
              [["True"], ["False"], ["True"]],
              [[Timestamp("2017-01-01")],
               [pd.NaT], [Timestamp("2017-01-02")]]
          ]
  
          for cond in conds:
              with tm.assert_raises_regex(ValueError, msg):
                  df.where(cond)
  
          df['b'] = 2
          conds = [
              [[0, 1], [1, 0], [1, 1]],
              Series([[0, 2], [5, 0], [4, 7]]),
              [["False", "True"], ["True", "False"],
               ["True", "True"]],
              DataFrame({'a': [2, 5, 7], 'b': [4, 8, 9]}),
              [[pd.NaT, Timestamp("2017-01-01")],
               [Timestamp("2017-01-02"), pd.NaT],
               [Timestamp("2017-01-03"), Timestamp("2017-01-03")]]
          ]
  
          for cond in conds:
              with tm.assert_raises_regex(ValueError, msg):
                  df.where(cond)
  
      def test_where_dataframe_col_match(self):
          df = DataFrame([[1, 2, 3], [4, 5, 6]])
          cond = DataFrame([[True, False, True], [False, False, True]])
  
          out = df.where(cond)
          expected = DataFrame([[1.0, np.nan, 3], [np.nan, np.nan, 6]])
          tm.assert_frame_equal(out, expected)
  
          cond.columns = ["a", "b", "c"]  # Columns no longer match.
          msg = "Boolean array expected for the condition"
          with tm.assert_raises_regex(ValueError, msg):
              df.where(cond)
  
      def test_where_ndframe_align(self):
          msg = "Array conditional must be same shape as self"
          df = DataFrame([[1, 2, 3], [4, 5, 6]])
  
          cond = [True]
          with tm.assert_raises_regex(ValueError, msg):
              df.where(cond)
  
          expected = DataFrame([[1, 2, 3], [np.nan, np.nan, np.nan]])
  
          out = df.where(Series(cond))
          tm.assert_frame_equal(out, expected)
  
          cond = np.array([False, True, False, True])
          with tm.assert_raises_regex(ValueError, msg):
              df.where(cond)
  
          expected = DataFrame([[np.nan, np.nan, np.nan], [4, 5, 6]])
  
          out = df.where(Series(cond))
          tm.assert_frame_equal(out, expected)
  
      def test_where_bug(self):
  
          # GH 2793
  
          df = DataFrame({'a': [1.0, 2.0, 3.0, 4.0], 'b': [
                         4.0, 3.0, 2.0, 1.0]}, dtype='float64')
          expected = DataFrame({'a': [np.nan, np.nan, 3.0, 4.0], 'b': [
                               4.0, 3.0, np.nan, np.nan]}, dtype='float64')
          result = df.where(df > 2, np.nan)
          assert_frame_equal(result, expected)
  
          result = df.copy()
          result.where(result > 2, np.nan, inplace=True)
          assert_frame_equal(result, expected)
  
          # mixed
          for dtype in ['int16', 'int8', 'int32', 'int64']:
              df = DataFrame({'a': np.array([1, 2, 3, 4], dtype=dtype),
                              'b': np.array([4.0, 3.0, 2.0, 1.0],
                                            dtype='float64')})
  
              expected = DataFrame({'a': [np.nan, np.nan, 3.0, 4.0],
                                    'b': [4.0, 3.0, np.nan, np.nan]},
                                   dtype='float64')
  
              result = df.where(df > 2, np.nan)
              assert_frame_equal(result, expected)
  
              result = df.copy()
              result.where(result > 2, np.nan, inplace=True)
              assert_frame_equal(result, expected)
  
          # transpositional issue
          # GH7506
          a = DataFrame({0: [1, 2], 1: [3, 4], 2: [5, 6]})
          b = DataFrame({0: [np.nan, 8], 1: [9, np.nan], 2: [np.nan, np.nan]})
          do_not_replace = b.isnull() | (a > b)
  
          expected = a.copy()
          expected[~do_not_replace] = b
  
          result = a.where(do_not_replace, b)
          assert_frame_equal(result, expected)
  
          a = DataFrame({0: [4, 6], 1: [1, 0]})
          b = DataFrame({0: [np.nan, 3], 1: [3, np.nan]})
          do_not_replace = b.isnull() | (a > b)
  
          expected = a.copy()
          expected[~do_not_replace] = b
  
          result = a.where(do_not_replace, b)
          assert_frame_equal(result, expected)
  
      def test_where_datetime(self):
  
          # GH 3311
          df = DataFrame(dict(A=date_range('20130102', periods=5),
                              B=date_range('20130104', periods=5),
                              C=np.random.randn(5)))
  
          stamp = datetime(2013, 1, 3)
          result = df[df > stamp]
          expected = df.copy()
          expected.loc[[0, 1], 'A'] = np.nan
          assert_frame_equal(result, expected)
  
      def test_where_none(self):
          # GH 4667
          # setting with None changes dtype
          df = DataFrame({'series': Series(range(10))}).astype(float)
          df[df > 7] = None
          expected = DataFrame(
              {'series': Series([0, 1, 2, 3, 4, 5, 6, 7, np.nan, np.nan])})
          assert_frame_equal(df, expected)
  
          # GH 7656
          df = DataFrame([{'A': 1, 'B': np.nan, 'C': 'Test'}, {
                         'A': np.nan, 'B': 'Test', 'C': np.nan}])
          expected = df.where(~isnull(df), None)
          with tm.assert_raises_regex(TypeError, 'boolean setting '
                                      'on mixed-type'):
              df.where(~isnull(df), None, inplace=True)
  
      def test_where_align(self):
  
          def create():
              df = DataFrame(np.random.randn(10, 3))
              df.iloc[3:5, 0] = np.nan
              df.iloc[4:6, 1] = np.nan
              df.iloc[5:8, 2] = np.nan
              return df
  
          # series
          df = create()
          expected = df.fillna(df.mean())
          result = df.where(pd.notnull(df), df.mean(), axis='columns')
          assert_frame_equal(result, expected)
  
          df.where(pd.notnull(df), df.mean(), inplace=True, axis='columns')
          assert_frame_equal(df, expected)
  
          df = create().fillna(0)
          expected = df.apply(lambda x, y: x.where(x > 0, y), y=df[0])
          result = df.where(df > 0, df[0], axis='index')
          assert_frame_equal(result, expected)
          result = df.where(df > 0, df[0], axis='rows')
          assert_frame_equal(result, expected)
  
          # frame
          df = create()
          expected = df.fillna(1)
          result = df.where(pd.notnull(df), DataFrame(
              1, index=df.index, columns=df.columns))
          assert_frame_equal(result, expected)
  
      def test_where_complex(self):
          # GH 6345
          expected = DataFrame(
              [[1 + 1j, 2], [np.nan, 4 + 1j]], columns=['a', 'b'])
          df = DataFrame([[1 + 1j, 2], [5 + 1j, 4 + 1j]], columns=['a', 'b'])
          df[df.abs() >= 5] = np.nan
          assert_frame_equal(df, expected)
  
      def test_where_axis(self):
          # GH 9736
          df = DataFrame(np.random.randn(2, 2))
          mask = DataFrame([[False, False], [False, False]])
          s = Series([0, 1])
  
          expected = DataFrame([[0, 0], [1, 1]], dtype='float64')
          result = df.where(mask, s, axis='index')
          assert_frame_equal(result, expected)
  
          result = df.copy()
          result.where(mask, s, axis='index', inplace=True)
          assert_frame_equal(result, expected)
  
          expected = DataFrame([[0, 1], [0, 1]], dtype='float64')
          result = df.where(mask, s, axis='columns')
          assert_frame_equal(result, expected)
  
          result = df.copy()
          result.where(mask, s, axis='columns', inplace=True)
          assert_frame_equal(result, expected)
  
          # Upcast needed
          df = DataFrame([[1, 2], [3, 4]], dtype='int64')
          mask = DataFrame([[False, False], [False, False]])
          s = Series([0, np.nan])
  
          expected = DataFrame([[0, 0], [np.nan, np.nan]], dtype='float64')
          result = df.where(mask, s, axis='index')
          assert_frame_equal(result, expected)
  
          result = df.copy()
          result.where(mask, s, axis='index', inplace=True)
          assert_frame_equal(result, expected)
  
          expected = DataFrame([[0, np.nan], [0, np.nan]], dtype='float64')
          result = df.where(mask, s, axis='columns')
          assert_frame_equal(result, expected)
  
          expected = DataFrame({0: np.array([0, 0], dtype='int64'),
                                1: np.array([np.nan, np.nan], dtype='float64')})
          result = df.copy()
          result.where(mask, s, axis='columns', inplace=True)
          assert_frame_equal(result, expected)
  
          # Multiple dtypes (=> multiple Blocks)
          df = pd.concat([DataFrame(np.random.randn(10, 2)),
                          DataFrame(np.random.randint(0, 10, size=(10, 2)))],
                         ignore_index=True, axis=1)
          mask = DataFrame(False, columns=df.columns, index=df.index)
          s1 = Series(1, index=df.columns)
          s2 = Series(2, index=df.index)
  
          result = df.where(mask, s1, axis='columns')
          expected = DataFrame(1.0, columns=df.columns, index=df.index)
          expected[2] = expected[2].astype(int)
          expected[3] = expected[3].astype(int)
          assert_frame_equal(result, expected)
  
          result = df.copy()
          result.where(mask, s1, axis='columns', inplace=True)
          assert_frame_equal(result, expected)
  
          result = df.where(mask, s2, axis='index')
          expected = DataFrame(2.0, columns=df.columns, index=df.index)
          expected[2] = expected[2].astype(int)
          expected[3] = expected[3].astype(int)
          assert_frame_equal(result, expected)
  
          result = df.copy()
          result.where(mask, s2, axis='index', inplace=True)
          assert_frame_equal(result, expected)
  
          # DataFrame vs DataFrame
          d1 = df.copy().drop(1, axis=0)
          expected = df.copy()
          expected.loc[1, :] = np.nan
  
          result = df.where(mask, d1)
          assert_frame_equal(result, expected)
          result = df.where(mask, d1, axis='index')
          assert_frame_equal(result, expected)
          result = df.copy()
          result.where(mask, d1, inplace=True)
          assert_frame_equal(result, expected)
          result = df.copy()
          result.where(mask, d1, inplace=True, axis='index')
          assert_frame_equal(result, expected)
  
          d2 = df.copy().drop(1, axis=1)
          expected = df.copy()
          expected.loc[:, 1] = np.nan
  
          result = df.where(mask, d2)
          assert_frame_equal(result, expected)
          result = df.where(mask, d2, axis='columns')
          assert_frame_equal(result, expected)
          result = df.copy()
          result.where(mask, d2, inplace=True)
          assert_frame_equal(result, expected)
          result = df.copy()
          result.where(mask, d2, inplace=True, axis='columns')
          assert_frame_equal(result, expected)
  
      def test_where_callable(self):
          # GH 12533
          df = DataFrame([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
          result = df.where(lambda x: x > 4, lambda x: x + 1)
          exp = DataFrame([[2, 3, 4], [5, 5, 6], [7, 8, 9]])
          tm.assert_frame_equal(result, exp)
          tm.assert_frame_equal(result, df.where(df > 4, df + 1))
  
          # return ndarray and scalar
          result = df.where(lambda x: (x % 2 == 0).values, lambda x: 99)
          exp = DataFrame([[99, 2, 99], [4, 99, 6], [99, 8, 99]])
          tm.assert_frame_equal(result, exp)
          tm.assert_frame_equal(result, df.where(df % 2 == 0, 99))
  
          # chain
          result = (df + 2).where(lambda x: x > 8, lambda x: x + 10)
          exp = DataFrame([[13, 14, 15], [16, 17, 18], [9, 10, 11]])
          tm.assert_frame_equal(result, exp)
          tm.assert_frame_equal(result,
                                (df + 2).where((df + 2) > 8, (df + 2) + 10))
  
      def test_mask(self):
          df = DataFrame(np.random.randn(5, 3))
          cond = df > 0
  
          rs = df.where(cond, np.nan)
          assert_frame_equal(rs, df.mask(df <= 0))
          assert_frame_equal(rs, df.mask(~cond))
  
          other = DataFrame(np.random.randn(5, 3))
          rs = df.where(cond, other)
          assert_frame_equal(rs, df.mask(df <= 0, other))
          assert_frame_equal(rs, df.mask(~cond, other))
  
      def test_mask_inplace(self):
          # GH8801
          df = DataFrame(np.random.randn(5, 3))
          cond = df > 0
  
          rdf = df.copy()
  
          rdf.where(cond, inplace=True)
          assert_frame_equal(rdf, df.where(cond))
          assert_frame_equal(rdf, df.mask(~cond))
  
          rdf = df.copy()
          rdf.where(cond, -df, inplace=True)
          assert_frame_equal(rdf, df.where(cond, -df))
          assert_frame_equal(rdf, df.mask(~cond, -df))
  
      def test_mask_edge_case_1xN_frame(self):
          # GH4071
          df = DataFrame([[1, 2]])
          res = df.mask(DataFrame([[True, False]]))
          expec = DataFrame([[nan, 2]])
          assert_frame_equal(res, expec)
  
      def test_mask_callable(self):
          # GH 12533
          df = DataFrame([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
          result = df.mask(lambda x: x > 4, lambda x: x + 1)
          exp = DataFrame([[1, 2, 3], [4, 6, 7], [8, 9, 10]])
          tm.assert_frame_equal(result, exp)
          tm.assert_frame_equal(result, df.mask(df > 4, df + 1))
  
          # return ndarray and scalar
          result = df.mask(lambda x: (x % 2 == 0).values, lambda x: 99)
          exp = DataFrame([[1, 99, 3], [99, 5, 99], [7, 99, 9]])
          tm.assert_frame_equal(result, exp)
          tm.assert_frame_equal(result, df.mask(df % 2 == 0, 99))
  
          # chain
          result = (df + 2).mask(lambda x: x > 8, lambda x: x + 10)
          exp = DataFrame([[3, 4, 5], [6, 7, 8], [19, 20, 21]])
          tm.assert_frame_equal(result, exp)
          tm.assert_frame_equal(result,
                                (df + 2).mask((df + 2) > 8, (df + 2) + 10))
  
      def test_head_tail(self):
          assert_frame_equal(self.frame.head(), self.frame[:5])
          assert_frame_equal(self.frame.tail(), self.frame[-5:])
  
          assert_frame_equal(self.frame.head(0), self.frame[0:0])
          assert_frame_equal(self.frame.tail(0), self.frame[0:0])
  
          assert_frame_equal(self.frame.head(-1), self.frame[:-1])
          assert_frame_equal(self.frame.tail(-1), self.frame[1:])
          assert_frame_equal(self.frame.head(1), self.frame[:1])
          assert_frame_equal(self.frame.tail(1), self.frame[-1:])
          # with a float index
          df = self.frame.copy()
          df.index = np.arange(len(self.frame)) + 0.1
          assert_frame_equal(df.head(), df.iloc[:5])
          assert_frame_equal(df.tail(), df.iloc[-5:])
          assert_frame_equal(df.head(0), df[0:0])
          assert_frame_equal(df.tail(0), df[0:0])
          assert_frame_equal(df.head(-1), df.iloc[:-1])
          assert_frame_equal(df.tail(-1), df.iloc[1:])
          # test empty dataframe
          empty_df = DataFrame()
          assert_frame_equal(empty_df.tail(), empty_df)
          assert_frame_equal(empty_df.head(), empty_df)
  
      def test_type_error_multiindex(self):
          # See gh-12218
          df = DataFrame(columns=['i', 'c', 'x', 'y'],
                         data=[[0, 0, 1, 2], [1, 0, 3, 4],
                               [0, 1, 1, 2], [1, 1, 3, 4]])
          dg = df.pivot_table(index='i', columns='c',
                              values=['x', 'y'])
  
          with tm.assert_raises_regex(TypeError, "is an invalid key"):
              str(dg[:, 0])
  
          index = Index(range(2), name='i')
          columns = MultiIndex(levels=[['x', 'y'], [0, 1]],
                               labels=[[0, 1], [0, 0]],
                               names=[None, 'c'])
          expected = DataFrame([[1, 2], [3, 4]], columns=columns, index=index)
  
          result = dg.loc[:, (slice(None), 0)]
          assert_frame_equal(result, expected)
  
          name = ('x', 0)
          index = Index(range(2), name='i')
          expected = Series([1, 3], index=index, name=name)
  
          result = dg['x', 0]
          assert_series_equal(result, expected)
  
  
  class TestDataFrameIndexingDatetimeWithTZ(TestData):
  
      def setup_method(self, method):
          self.idx = Index(date_range('20130101', periods=3, tz='US/Eastern'),
                           name='foo')
          self.dr = date_range('20130110', periods=3)
          self.df = DataFrame({'A': self.idx, 'B': self.dr})
  
      def test_setitem(self):
  
          df = self.df
          idx = self.idx
  
          # setitem
          df['C'] = idx
          assert_series_equal(df['C'], Series(idx, name='C'))
  
          df['D'] = 'foo'
          df['D'] = idx
          assert_series_equal(df['D'], Series(idx, name='D'))
          del df['D']
  
          # assert that A & C are not sharing the same base (e.g. they
          # are copies)
          b1 = df._data.blocks[1]
          b2 = df._data.blocks[2]
          assert b1.values.equals(b2.values)
          assert id(b1.values.values.base) != id(b2.values.values.base)
  
          # with nan
          df2 = df.copy()
          df2.iloc[1, 1] = pd.NaT
          df2.iloc[1, 2] = pd.NaT
          result = df2['B']
          assert_series_equal(notnull(result), Series(
              [True, False, True], name='B'))
          assert_series_equal(df2.dtypes, df.dtypes)
  
      def test_set_reset(self):
  
          idx = self.idx
  
          # set/reset
          df = DataFrame({'A': [0, 1, 2]}, index=idx)
          result = df.reset_index()
          assert result['foo'].dtype, 'M8[ns, US/Eastern'
  
          df = result.set_index('foo')
          tm.assert_index_equal(df.index, idx)
  
      def test_transpose(self):
  
          result = self.df.T
          expected = DataFrame(self.df.values.T)
          expected.index = ['A', 'B']
          assert_frame_equal(result, expected)
  
  
  class TestDataFrameIndexingUInt64(TestData):
  
      def setup_method(self, method):
          self.ir = Index(np.arange(3), dtype=np.uint64)
          self.idx = Index([2**63, 2**63 + 5, 2**63 + 10], name='foo')
  
          self.df = DataFrame({'A': self.idx, 'B': self.ir})
  
      def test_setitem(self):
  
          df = self.df
          idx = self.idx
  
          # setitem
          df['C'] = idx
          assert_series_equal(df['C'], Series(idx, name='C'))
  
          df['D'] = 'foo'
          df['D'] = idx
          assert_series_equal(df['D'], Series(idx, name='D'))
          del df['D']
  
          # With NaN: because uint64 has no NaN element,
          # the column should be cast to object.
          df2 = df.copy()
          df2.iloc[1, 1] = pd.NaT
          df2.iloc[1, 2] = pd.NaT
          result = df2['B']
          assert_series_equal(notnull(result), Series(
              [True, False, True], name='B'))
          assert_series_equal(df2.dtypes, Series([np.dtype('uint64'),
                                                  np.dtype('O'), np.dtype('O')],
                                                 index=['A', 'B', 'C']))
  
      def test_set_reset(self):
  
          idx = self.idx
  
          # set/reset
          df = DataFrame({'A': [0, 1, 2]}, index=idx)
          result = df.reset_index()
          assert result['foo'].dtype == np.dtype('uint64')
  
          df = result.set_index('foo')
          tm.assert_index_equal(df.index, idx)
  
      def test_transpose(self):
  
          result = self.df.T
          expected = DataFrame(self.df.values.T)
          expected.index = ['A', 'B']
          assert_frame_equal(result, expected)
  