import os
import mne

sample_data_folder = mne.datasets.sample.data_path()
sample_data_raw_file = os.path.join(sample_data_folder, 'MEG', 'sample',
                                    'sample_audvis_raw.fif')
raw = mne.io.read_raw_fif(sample_data_raw_file, verbose=False).crop(tmax=120)

"""
Explanation: Visualizing epoched data
This tutorial shows how to plot epoched data as time series, how to plot the
spectral density of epoched data, how to plot epochs as an imagemap, and how to
plot the sensor locations and projectors stored in ~mne.Epochs objects.
We'll start by importing the modules we need, loading the continuous (raw)
sample data, and cropping it to save memory:
End of explanation
"""


events = mne.find_events(raw, stim_channel='STI 014')
event_dict = {'auditory/left': 1, 'auditory/right': 2, 'visual/left': 3,
              'visual/right': 4, 'face': 5, 'button': 32}
epochs = mne.Epochs(raw, events, tmin=-0.2, tmax=0.5, event_id=event_dict,
                    preload=True)
del raw

"""
Explanation: To create the ~mne.Epochs data structure, we'll extract the event
IDs stored in the :term:stim channel, map those integer event IDs to more
descriptive condition labels using an event dictionary, and pass those to the
~mne.Epochs constructor, along with the ~mne.io.Raw data and the
desired temporal limits of our epochs, tmin and tmax (for a
detailed explanation of these steps, see tut-epochs-class).
End of explanation
"""


catch_trials_and_buttonpresses = mne.pick_events(events, include=[5, 32])
epochs['face'].plot(events=catch_trials_and_buttonpresses, event_id=event_dict,
                    event_color=dict(button='red', face='blue'))

"""
Explanation: Plotting Epochs as time series
.. sidebar:: Interactivity in pipelines and scripts
To use the interactive features of the `~mne.Epochs.plot` method
when running your code non-interactively, pass the ``block=True``
parameter, which halts the Python interpreter until the figure window is
closed. That way, any channels or epochs that you mark as "bad" will be
taken into account in subsequent processing steps.

To visualize epoched data as time series (one time series per channel), the
mne.Epochs.plot method is available. It creates an interactive window
where you can scroll through epochs and channels, enable/disable any
unapplied :term:SSP projectors &lt;projector&gt; to see how they affect the
signal, and even manually mark bad channels (by clicking the channel name) or
bad epochs (by clicking the data) for later dropping. Channels marked "bad"
will be shown in light grey color and will be added to
epochs.info['bads']; epochs marked as bad will be indicated as 'USER'
in epochs.drop_log.
Here we'll plot only the "catch" trials from the sample dataset
&lt;sample-dataset&gt;, and pass in our events array so that the button press
responses also get marked (we'll plot them in red, and plot the "face" events
defining time zero for each epoch in blue). We also need to pass in
our event_dict so that the ~mne.Epochs.plot method will know what
we mean by "button" — this is because subsetting the conditions by
calling epochs['face'] automatically purges the dropped entries from
epochs.event_id:
End of explanation
"""


epochs['face'].plot(events=catch_trials_and_buttonpresses, event_id=event_dict,
                    event_color=dict(button='red', face='blue'),
                    group_by='selection', butterfly=True)

"""
Explanation: To see all sensors at once, we can use butterfly mode and group by selection:
End of explanation
"""


ecg_proj_file = os.path.join(sample_data_folder, 'MEG', 'sample',
                             'sample_audvis_ecg-proj.fif')
ecg_projs = mne.read_proj(ecg_proj_file)
epochs.add_proj(ecg_projs)
epochs.apply_proj()

"""
Explanation: Plotting projectors from an Epochs object
In the plot above we can see heartbeat artifacts in the magnetometer
channels, so before we continue let's load ECG projectors from disk and apply
them to the data:
End of explanation
"""


epochs.plot_projs_topomap(vlim='joint')

"""
Explanation: Just as we saw in the tut-section-raw-plot-proj section, we can plot
the projectors present in an ~mne.Epochs object using the same
~mne.Epochs.plot_projs_topomap method. Since the original three
empty-room magnetometer projectors were inherited from the
~mne.io.Raw file, and we added two ECG projectors for each sensor
type, we should see nine projector topomaps:
End of explanation
"""


print(all(proj['active'] for proj in epochs.info['projs']))

"""
Explanation: Note that these field maps illustrate aspects of the signal that have
already been removed (because projectors in ~mne.io.Raw data are
applied by default when epoching, and because we called
~mne.Epochs.apply_proj after adding additional ECG projectors from
file). You can check this by examining the 'active' field of the
projectors:
End of explanation
"""


epochs.plot_sensors(kind='3d', ch_type='all')
epochs.plot_sensors(kind='topomap', ch_type='all')

"""
Explanation: Plotting sensor locations
Just like ~mne.io.Raw objects, ~mne.Epochs objects
keep track of sensor locations, which can be visualized with the
~mne.Epochs.plot_sensors method:
End of explanation
"""


epochs['auditory'].plot_psd(picks='eeg')

"""
Explanation: Plotting the power spectrum of Epochs
Again, just like ~mne.io.Raw objects, ~mne.Epochs objects
have a ~mne.Epochs.plot_psd method for plotting the spectral
density_ of the data.
End of explanation
"""


epochs['visual/right'].plot_psd_topomap()

"""
Explanation: It is also possible to plot spectral estimates across sensors as a scalp
topography, using ~mne.Epochs.plot_psd_topomap. The default parameters will
plot five frequency bands (δ, θ, α, β, γ), will compute power based on
magnetometer channels, and will plot the power estimates in decibels:
End of explanation
"""


bands = [(10, '10 Hz'), (15, '15 Hz'), (20, '20 Hz'), (10, 20, '10-20 Hz')]
epochs['visual/right'].plot_psd_topomap(bands=bands, vlim='joint',
                                        ch_type='grad')

"""
Explanation: Just like ~mne.Epochs.plot_projs_topomap,
~mne.Epochs.plot_psd_topomap has a vlim='joint' option for fixing
the colorbar limits jointly across all subplots, to give a better sense of
the relative magnitude in each frequency band. You can change which channel
type is used  via the ch_type parameter, and if you want to view
different frequency bands than the defaults, the bands parameter takes a
list of tuples, with each tuple containing either a single frequency and a
subplot title, or lower/upper frequency limits and a subplot title:
End of explanation
"""


epochs['auditory'].plot_image(picks='mag', combine='mean')

"""
Explanation: If you prefer untransformed power estimates, you can pass dB=False. It is
also possible to normalize the power estimates by dividing by the total power
across all frequencies, by passing normalize=True. See the docstring of
~mne.Epochs.plot_psd_topomap for details.
Plotting Epochs as an image map
A convenient way to visualize many epochs simultaneously is to plot them as
an image map, with each row of pixels in the image representing a single
epoch, the horizontal axis representing time, and each pixel's color
representing the signal value at that time sample for that epoch. Of course,
this requires either a separate image map for each channel, or some way of
combining information across channels. The latter is possible using the
~mne.Epochs.plot_image method; the former can be achieved with the
~mne.Epochs.plot_image method (one channel at a time) or with the
~mne.Epochs.plot_topo_image method (all sensors at once).
By default, the image map generated by ~mne.Epochs.plot_image will be
accompanied by a scalebar indicating the range of the colormap, and a time
series showing the average signal across epochs and a bootstrapped 95%
confidence band around the mean. ~mne.Epochs.plot_image is a highly
customizable method with many parameters, including customization of the
auxiliary colorbar and averaged time series subplots. See the docstrings of
~mne.Epochs.plot_image and mne.viz.plot_compare_evokeds (which is
used to plot the average time series) for full details. Here we'll show the
mean across magnetometers for all epochs with an auditory stimulus:
End of explanation
"""


epochs['auditory'].plot_image(picks=['MEG 0242', 'MEG 0243'])
epochs['auditory'].plot_image(picks=['MEG 0242', 'MEG 0243'], combine='gfp')

"""
Explanation: To plot image maps for individual sensors or a small group of sensors, use
the picks parameter. Passing combine=None (the default) will yield
separate plots for each sensor in picks; passing combine='gfp' will
plot the global field power (useful for combining sensors that respond with
opposite polarity).
End of explanation
"""


reject_criteria = dict(mag=3000e-15,     # 3000 fT
                       grad=3000e-13,    # 3000 fT/cm
                       eeg=150e-6)       # 150 µV
epochs.drop_bad(reject=reject_criteria)

for ch_type, title in dict(mag='Magnetometers', grad='Gradiometers').items():
    layout = mne.channels.find_layout(epochs.info, ch_type=ch_type)
    epochs['auditory/left'].plot_topo_image(layout=layout, fig_facecolor='w',
                                            font_color='k', title=title)

"""
Explanation: To plot an image map for all sensors, use
~mne.Epochs.plot_topo_image, which is optimized for plotting a large
number of image maps simultaneously, and (in interactive sessions) allows you
to click on each small image map to pop open a separate figure with the
full-sized image plot (as if you had called ~mne.Epochs.plot_image on
just that sensor). At the small scale shown in this tutorial it's hard to see
much useful detail in these plots; it's often best when plotting
interactively to maximize the topo image plots to fullscreen. The default is
a figure with black background, so here we specify a white background and
black foreground text. By default ~mne.Epochs.plot_topo_image will
show magnetometers and gradiometers on the same plot (and hence not show a
colorbar, since the sensors are on different scales) so we'll also pass a
~mne.channels.Layout restricting each plot to one channel type.
First, however, we'll also drop any epochs that have unusually high signal
levels, because they can cause the colormap limits to be too extreme and
therefore mask smaller signal fluctuations of interest.
End of explanation
"""


layout = mne.channels.find_layout(epochs.info, ch_type='eeg')
epochs['auditory/left'].plot_topo_image(layout=layout, fig_facecolor='w',
                                        font_color='k', sigma=1)

"""
Explanation: To plot image maps for all EEG sensors, pass an EEG layout as the layout
parameter of ~mne.Epochs.plot_topo_image. Note also here the use of
the sigma parameter, which smooths each image map along the vertical
dimension (across epochs) which can make it easier to see patterns across the
small image maps (by smearing noisy epochs onto their neighbors, while
reinforcing parts of the image where adjacent epochs are similar). However,
sigma can also disguise epochs that have persistent extreme values and
maybe should have been excluded, so it should be used with caution.
End of explanation
"""


