# Authors: The MNE-Python contributors.
# License: BSD-3-Clause
# Copyright the MNE-Python contributors.
from __future__ import annotations # only needed for Python ≤ 3.9
from copy import deepcopy
from inspect import getfullargspec
from pathlib import Path
import numpy as np
from ._fiff.constants import FIFF
from ._fiff.meas_info import (
ContainsMixin,
SetChannelsMixin,
_ensure_infos_match,
_read_extended_ch_info,
_rename_list,
read_meas_info,
write_meas_info,
)
from ._fiff.open import fiff_open
from ._fiff.pick import _FNIRS_CH_TYPES_SPLIT, _picks_to_idx, pick_types
from ._fiff.proj import ProjMixin
from ._fiff.tag import read_tag
from ._fiff.tree import dir_tree_find
from ._fiff.write import (
end_block,
start_and_end_file,
start_block,
write_complex_float_matrix,
write_float,
write_float_matrix,
write_id,
write_int,
write_string,
)
from .baseline import _check_baseline, _log_rescale, rescale
from .channels.channels import InterpolationMixin, ReferenceMixin, UpdateChannelsMixin
from .channels.layout import _merge_ch_data, _pair_grad_sensors
from .defaults import _BORDER_DEFAULT, _EXTRAPOLATE_DEFAULT, _INTERPOLATION_DEFAULT
from .filter import FilterMixin, _check_fun, detrend
from .html_templates import _get_html_template
from .parallel import parallel_func
from .time_frequency.spectrum import Spectrum, SpectrumMixin, _validate_method
from .time_frequency.tfr import AverageTFR
from .utils import (
ExtendedTimeMixin,
SizeMixin,
_build_data_frame,
_check_fname,
_check_option,
_check_pandas_index_arguments,
_check_pandas_installed,
_check_preload,
_check_time_format,
_convert_times,
_scale_dataframe_data,
_validate_type,
check_fname,
copy_function_doc_to_method_doc,
fill_doc,
logger,
repr_html,
sizeof_fmt,
verbose,
warn,
)
from .viz import (
plot_evoked,
plot_evoked_field,
plot_evoked_image,
plot_evoked_topo,
plot_evoked_topomap,
)
from .viz.evoked import plot_evoked_joint, plot_evoked_white
from .viz.topomap import _topomap_animation
_aspect_dict = {
"average": FIFF.FIFFV_ASPECT_AVERAGE,
"standard_error": FIFF.FIFFV_ASPECT_STD_ERR,
"single_epoch": FIFF.FIFFV_ASPECT_SINGLE,
"partial_average": FIFF.FIFFV_ASPECT_SUBAVERAGE,
"alternating_subaverage": FIFF.FIFFV_ASPECT_ALTAVERAGE,
"sample_cut_out_by_graph": FIFF.FIFFV_ASPECT_SAMPLE,
"power_density_spectrum": FIFF.FIFFV_ASPECT_POWER_DENSITY,
"dipole_amplitude_cuvre": FIFF.FIFFV_ASPECT_DIPOLE_WAVE,
"squid_modulation_lower_bound": FIFF.FIFFV_ASPECT_IFII_LOW,
"squid_modulation_upper_bound": FIFF.FIFFV_ASPECT_IFII_HIGH,
"squid_gate_setting": FIFF.FIFFV_ASPECT_GATE,
}
_aspect_rev = {val: key for key, val in _aspect_dict.items()}
@fill_doc
class Evoked(
ProjMixin,
ContainsMixin,
UpdateChannelsMixin,
ReferenceMixin,
SetChannelsMixin,
InterpolationMixin,
FilterMixin,
ExtendedTimeMixin,
SizeMixin,
SpectrumMixin,
):
"""Evoked data.
Parameters
----------
fname : path-like
Name of evoked/average FIF file to load.
If None no data is loaded.
condition : int, or str
Dataset ID number (int) or comment/name (str). Optional if there is
only one data set in file.
proj : bool, optional
Apply SSP projection vectors.
kind : str
Either ``'average'`` or ``'standard_error'``. The type of data to read.
Only used if 'condition' is a str.
allow_maxshield : bool | str (default False)
If True, allow loading of data that has been recorded with internal
active compensation (MaxShield). Data recorded with MaxShield should
generally not be loaded directly, but should first be processed using
SSS/tSSS to remove the compensation signals that may also affect brain
activity. Can also be ``"yes"`` to load without eliciting a warning.
%(verbose)s
Attributes
----------
%(info_not_none)s
ch_names : list of str
List of channels' names.
nave : int
Number of averaged epochs.
kind : str
Type of data, either average or standard_error.
comment : str
Comment on dataset. Can be the condition.
data : array of shape (n_channels, n_times)
Evoked response.
first : int
First time sample.
last : int
Last time sample.
tmin : float
The first time point in seconds.
tmax : float
The last time point in seconds.
times : array
Time vector in seconds. Goes from ``tmin`` to ``tmax``. Time interval
between consecutive time samples is equal to the inverse of the
sampling frequency.
baseline : None | tuple of length 2
This attribute reflects whether the data has been baseline-corrected
(it will be a ``tuple`` then) or not (it will be ``None``).
Notes
-----
Evoked objects can only contain the average of a single set of conditions.
"""
@verbose
def __init__(
self,
fname,
condition=None,
proj=True,
kind="average",
allow_maxshield=False,
*,
verbose=None,
):
_validate_type(proj, bool, "'proj'")
# Read the requested data
fname = _check_fname(fname=fname, must_exist=True, overwrite="read")
(
self.info,
self.nave,
self._aspect_kind,
self.comment,
times,
self.data,
self.baseline,
) = _read_evoked(fname, condition, kind, allow_maxshield)
self._set_times(times)
self._raw_times = self.times.copy()
self._decim = 1
self._update_first_last()
self.preload = True
# project and baseline correct
if proj:
self.apply_proj()
self.filename = fname
@property
def filename(self) -> Path | None:
"""The filename of the evoked object, if it exists.
:type: :class:`~pathlib.Path` | None
"""
return self._filename
@filename.setter
def filename(self, value):
self._filename = Path(value) if value is not None else value
@property
def kind(self):
"""The data kind."""
return _aspect_rev[self._aspect_kind]
@kind.setter
def kind(self, kind):
_check_option("kind", kind, list(_aspect_dict.keys()))
self._aspect_kind = _aspect_dict[kind]
@property
def data(self):
"""The data matrix."""
return self._data
@data.setter
def data(self, data):
"""Set the data matrix."""
self._data = data
@fill_doc
def get_data(self, picks=None, units=None, tmin=None, tmax=None):
"""Get evoked data as 2D array.
Parameters
----------
%(picks_all)s
%(units)s
tmin : float | None
Start time of data to get in seconds.
tmax : float | None
End time of data to get in seconds.
Returns
-------
data : ndarray, shape (n_channels, n_times)
A view on evoked data.
Notes
-----
.. versionadded:: 0.24
"""
# Avoid circular import
from .io.base import _get_ch_factors
picks = _picks_to_idx(self.info, picks, "all", exclude=())
start, stop = self._handle_tmin_tmax(tmin, tmax)
data = self.data[picks, start:stop]
if units is not None:
ch_factors = _get_ch_factors(self, units, picks)
data *= ch_factors[:, np.newaxis]
return data
@verbose
def apply_function(
self,
fun,
picks=None,
dtype=None,
n_jobs=None,
channel_wise=True,
*,
verbose=None,
**kwargs,
):
"""Apply a function to a subset of channels.
%(applyfun_summary_evoked)s
Parameters
----------
%(fun_applyfun_evoked)s
%(picks_all_data_noref)s
%(dtype_applyfun)s
%(n_jobs)s Ignored if ``channel_wise=False`` as the workload
is split across channels.
%(channel_wise_applyfun)s
.. versionadded:: 1.6
%(verbose)s
%(kwargs_fun)s
Returns
-------
self : instance of Evoked
The evoked object with transformed data.
"""
_check_preload(self, "evoked.apply_function")
picks = _picks_to_idx(self.info, picks, exclude=(), with_ref_meg=False)
if not callable(fun):
raise ValueError("fun needs to be a function")
data_in = self._data
if dtype is not None and dtype != self._data.dtype:
self._data = self._data.astype(dtype)
args = getfullargspec(fun).args + getfullargspec(fun).kwonlyargs
if channel_wise is False:
if ("ch_idx" in args) or ("ch_name" in args):
raise ValueError(
"apply_function cannot access ch_idx or ch_name "
"when channel_wise=False"
)
if "ch_idx" in args:
logger.info("apply_function requested to access ch_idx")
if "ch_name" in args:
logger.info("apply_function requested to access ch_name")
# check the dimension of the incoming evoked data
_check_option("evoked.ndim", self._data.ndim, [2])
if channel_wise:
parallel, p_fun, n_jobs = parallel_func(_check_fun, n_jobs)
if n_jobs == 1:
# modify data inplace to save memory
for ch_idx in picks:
if "ch_idx" in args:
kwargs.update(ch_idx=ch_idx)
if "ch_name" in args:
kwargs.update(ch_name=self.info["ch_names"][ch_idx])
self._data[ch_idx, :] = _check_fun(
fun, data_in[ch_idx, :], **kwargs
)
else:
# use parallel function
data_picks_new = parallel(
p_fun(
fun,
data_in[ch_idx, :],
**kwargs,
**{
k: v
for k, v in [
("ch_name", self.info["ch_names"][ch_idx]),
("ch_idx", ch_idx),
]
if k in args
},
)
for ch_idx in picks
)
for run_idx, ch_idx in enumerate(picks):
self._data[ch_idx, :] = data_picks_new[run_idx]
else:
self._data[picks, :] = _check_fun(fun, data_in[picks, :], **kwargs)
return self
@verbose
def apply_baseline(self, baseline=(None, 0), *, verbose=None):
"""Baseline correct evoked data.
Parameters
----------
%(baseline_evoked)s
Defaults to ``(None, 0)``, i.e. beginning of the the data until
time point zero.
%(verbose)s
Returns
-------
evoked : instance of Evoked
The baseline-corrected Evoked object.
Notes
-----
Baseline correction can be done multiple times.
.. versionadded:: 0.13.0
"""
baseline = _check_baseline(baseline, times=self.times, sfreq=self.info["sfreq"])
if self.baseline is not None and baseline is None:
raise ValueError(
"The data has already been baseline-corrected. "
"Cannot remove existing baseline correction."
)
elif baseline is None:
# Do not rescale
logger.info(_log_rescale(None))
else:
# Actually baseline correct the data. Logging happens in rescale().
self.data = rescale(self.data, self.times, baseline, copy=False)
self.baseline = baseline
return self
@verbose
def save(self, fname, *, overwrite=False, verbose=None):
"""Save evoked data to a file.
Parameters
----------
fname : path-like
The name of the file, which should end with ``-ave.fif(.gz)`` or
``_ave.fif(.gz)``.
%(overwrite)s
%(verbose)s
Notes
-----
To write multiple conditions into a single file, use
`mne.write_evokeds`.
.. versionchanged:: 0.23
Information on baseline correction will be stored with the data,
and will be restored when reading again via `mne.read_evokeds`.
"""
write_evokeds(fname, self, overwrite=overwrite)
@verbose
def export(self, fname, fmt="auto", *, overwrite=False, verbose=None):
"""Export Evoked to external formats.
%(export_fmt_support_evoked)s
%(export_warning)s
Parameters
----------
%(fname_export_params)s
%(export_fmt_params_evoked)s
%(overwrite)s
%(verbose)s
Notes
-----
.. versionadded:: 1.1
%(export_warning_note_evoked)s
"""
from .export import export_evokeds
export_evokeds(fname, self, fmt, overwrite=overwrite, verbose=verbose)
def __repr__(self): # noqa: D105
max_comment_length = 1000
if len(self.comment) > max_comment_length:
comment = self.comment[:max_comment_length]
comment += "..."
else:
comment = self.comment
s = f"'{comment}' ({self.kind}, N={self.nave})"
s += f", {self.times[0]:0.5g} – {self.times[-1]:0.5g} s"
s += ", baseline "
if self.baseline is None:
s += "off"
else:
s += f"{self.baseline[0]:g} – {self.baseline[1]:g} s"
if self.baseline != _check_baseline(
self.baseline,
times=self.times,
sfreq=self.info["sfreq"],
on_baseline_outside_data="adjust",
):
s += " (baseline period was cropped after baseline correction)"
s += f", {self.data.shape[0]} ch"
s += f", ~{sizeof_fmt(self._size)}"
return f"<Evoked | {s}>"
@repr_html
def _repr_html_(self):
t = _get_html_template("repr", "evoked.html.jinja")
t = t.render(
inst=self,
filenames=(
[Path(self.filename).name]
if getattr(self, "filename", None) is not None
else None
),
)
return t
@property
def ch_names(self):
"""Channel names."""
return self.info["ch_names"]
@copy_function_doc_to_method_doc(plot_evoked)
def plot(
self,
picks=None,
exclude="bads",
unit=True,
show=True,
ylim=None,
xlim="tight",
proj=False,
hline=None,
units=None,
scalings=None,
titles=None,
axes=None,
gfp=False,
window_title=None,
spatial_colors="auto",
zorder="unsorted",
selectable=True,
noise_cov=None,
time_unit="s",
sphere=None,
*,
highlight=None,
verbose=None,
):
return plot_evoked(
self,
picks=picks,
exclude=exclude,
unit=unit,
show=show,
ylim=ylim,
proj=proj,
xlim=xlim,
hline=hline,
units=units,
scalings=scalings,
titles=titles,
axes=axes,
gfp=gfp,
window_title=window_title,
spatial_colors=spatial_colors,
zorder=zorder,
selectable=selectable,
noise_cov=noise_cov,
time_unit=time_unit,
sphere=sphere,
highlight=highlight,
verbose=verbose,
)
@copy_function_doc_to_method_doc(plot_evoked_image)
def plot_image(
self,
picks=None,
exclude="bads",
unit=True,
show=True,
clim=None,
xlim="tight",
proj=False,
units=None,
scalings=None,
titles=None,
axes=None,
cmap="RdBu_r",
colorbar=True,
mask=None,
mask_style=None,
mask_cmap="Greys",
mask_alpha=0.25,
time_unit="s",
show_names=None,
group_by=None,
sphere=None,
):
return plot_evoked_image(
self,
picks=picks,
exclude=exclude,
unit=unit,
show=show,
clim=clim,
xlim=xlim,
proj=proj,
units=units,
scalings=scalings,
titles=titles,
axes=axes,
cmap=cmap,
colorbar=colorbar,
mask=mask,
mask_style=mask_style,
mask_cmap=mask_cmap,
mask_alpha=mask_alpha,
time_unit=time_unit,
show_names=show_names,
group_by=group_by,
sphere=sphere,
)
@copy_function_doc_to_method_doc(plot_evoked_topo)
def plot_topo(
self,
layout=None,
layout_scale=0.945,
color=None,
border="none",
ylim=None,
scalings=None,
title=None,
proj=False,
vline=(0.0,),
fig_background=None,
merge_grads=False,
legend=True,
axes=None,
background_color="w",
noise_cov=None,
exclude="bads",
select=False,
show=True,
):
""".
Notes
-----
.. versionadded:: 0.10.0
"""
return plot_evoked_topo(
self,
layout=layout,
layout_scale=layout_scale,
color=color,
border=border,
ylim=ylim,
scalings=scalings,
title=title,
proj=proj,
vline=vline,
fig_background=fig_background,
merge_grads=merge_grads,
legend=legend,
axes=axes,
background_color=background_color,
noise_cov=noise_cov,
exclude=exclude,
select=select,
show=show,
)
@copy_function_doc_to_method_doc(plot_evoked_topomap)
def plot_topomap(
self,
times="auto",
*,
average=None,
ch_type=None,
scalings=None,
proj=False,
sensors=True,
show_names=False,
mask=None,
mask_params=None,
contours=6,
outlines="head",
sphere=None,
image_interp=_INTERPOLATION_DEFAULT,
extrapolate=_EXTRAPOLATE_DEFAULT,
border=_BORDER_DEFAULT,
res=64,
size=1,
cmap=None,
vlim=(None, None),
cnorm=None,
colorbar=True,
cbar_fmt="%3.1f",
units=None,
axes=None,
time_unit="s",
time_format=None,
nrows=1,
ncols="auto",
show=True,
):
return plot_evoked_topomap(
self,
times=times,
ch_type=ch_type,
vlim=vlim,
cmap=cmap,
cnorm=cnorm,
sensors=sensors,
colorbar=colorbar,
scalings=scalings,
units=units,
res=res,
size=size,
cbar_fmt=cbar_fmt,
time_unit=time_unit,
time_format=time_format,
proj=proj,
show=show,
show_names=show_names,
mask=mask,
mask_params=mask_params,
outlines=outlines,
contours=contours,
image_interp=image_interp,
average=average,
axes=axes,
extrapolate=extrapolate,
sphere=sphere,
border=border,
nrows=nrows,
ncols=ncols,
)
@copy_function_doc_to_method_doc(plot_evoked_field)
def plot_field(
self,
surf_maps,
time=None,
time_label="t = %0.0f ms",
n_jobs=None,
fig=None,
vmax=None,
n_contours=21,
*,
show_density=True,
alpha=None,
interpolation="nearest",
interaction="terrain",
time_viewer="auto",
verbose=None,
):
return plot_evoked_field(
self,
surf_maps,
time=time,
time_label=time_label,
n_jobs=n_jobs,
fig=fig,
vmax=vmax,
n_contours=n_contours,
show_density=show_density,
alpha=alpha,
interpolation=interpolation,
interaction=interaction,
time_viewer=time_viewer,
verbose=verbose,
)
@copy_function_doc_to_method_doc(plot_evoked_white)
def plot_white(
self,
noise_cov,
show=True,
rank=None,
time_unit="s",
sphere=None,
axes=None,
*,
spatial_colors="auto",
verbose=None,
):
return plot_evoked_white(
self,
noise_cov=noise_cov,
rank=rank,
show=show,
time_unit=time_unit,
sphere=sphere,
axes=axes,
spatial_colors=spatial_colors,
verbose=verbose,
)
@copy_function_doc_to_method_doc(plot_evoked_joint)
def plot_joint(
self,
times="peaks",
title="",
picks=None,
exclude="bads",
show=True,
ts_args=None,
topomap_args=None,
):
return plot_evoked_joint(
self,
times=times,
title=title,
picks=picks,
exclude=exclude,
show=show,
ts_args=ts_args,
topomap_args=topomap_args,
)
@fill_doc
def animate_topomap(
self,
ch_type=None,
times=None,
frame_rate=None,
butterfly=False,
blit=True,
show=True,
time_unit="s",
sphere=None,
*,
image_interp=_INTERPOLATION_DEFAULT,
extrapolate=_EXTRAPOLATE_DEFAULT,
vmin=None,
vmax=None,
verbose=None,
):
"""Make animation of evoked data as topomap timeseries.
The animation can be paused/resumed with left mouse button.
Left and right arrow keys can be used to move backward or forward
in time.
Parameters
----------
ch_type : str | None
Channel type to plot. Accepted data types: 'mag', 'grad', 'eeg',
'hbo', 'hbr', 'fnirs_cw_amplitude',
'fnirs_fd_ac_amplitude', 'fnirs_fd_phase', and 'fnirs_od'.
If None, first available channel type from the above list is used.
Defaults to None.
times : array of float | None
The time points to plot. If None, 10 evenly spaced samples are
calculated over the evoked time series. Defaults to None.
frame_rate : int | None
Frame rate for the animation in Hz. If None,
frame rate = sfreq / 10. Defaults to None.
butterfly : bool
Whether to plot the data as butterfly plot under the topomap.
Defaults to False.
blit : bool
Whether to use blit to optimize drawing. In general, it is
recommended to use blit in combination with ``show=True``. If you
intend to save the animation it is better to disable blit.
Defaults to True.
show : bool
Whether to show the animation. Defaults to True.
time_unit : str
The units for the time axis, can be "ms" (default in 0.16)
or "s" (will become the default in 0.17).
.. versionadded:: 0.16
%(sphere_topomap_auto)s
%(image_interp_topomap)s
%(extrapolate_topomap)s
.. versionadded:: 0.22
%(vmin_vmax_topomap)s
.. versionadded:: 1.1.0
%(verbose)s
Returns
-------
fig : instance of matplotlib.figure.Figure
The figure.
anim : instance of matplotlib.animation.FuncAnimation
Animation of the topomap.
Notes
-----
.. versionadded:: 0.12.0
"""
return _topomap_animation(
self,
ch_type=ch_type,
times=times,
frame_rate=frame_rate,
butterfly=butterfly,
blit=blit,
show=show,
time_unit=time_unit,
sphere=sphere,
image_interp=image_interp,
extrapolate=extrapolate,
vmin=vmin,
vmax=vmax,
verbose=verbose,
)
def as_type(self, ch_type="grad", mode="fast"):
"""Compute virtual evoked using interpolated fields.
.. Warning:: Using virtual evoked to compute inverse can yield
unexpected results. The virtual channels have ``'_v'`` appended
at the end of the names to emphasize that the data contained in
them are interpolated.
Parameters
----------
ch_type : str
The destination channel type. It can be 'mag' or 'grad'.
mode : str
Either ``'accurate'`` or ``'fast'``, determines the quality of the
Legendre polynomial expansion used. ``'fast'`` should be sufficient
for most applications.
Returns
-------
evoked : instance of mne.Evoked
The transformed evoked object containing only virtual channels.
Notes
-----
This method returns a copy and does not modify the data it
operates on. It also returns an EvokedArray instance.
.. versionadded:: 0.9.0
"""
from .forward import _as_meg_type_inst
return _as_meg_type_inst(self, ch_type=ch_type, mode=mode)
@fill_doc
def detrend(self, order=1, picks=None):
"""Detrend data.
This function operates in-place.
Parameters
----------
order : int
Either 0 or 1, the order of the detrending. 0 is a constant
(DC) detrend, 1 is a linear detrend.
%(picks_good_data)s
Returns
-------
evoked : instance of Evoked
The detrended evoked object.
"""
picks = _picks_to_idx(self.info, picks)
self.data[picks] = detrend(self.data[picks], order, axis=-1)
return self
def copy(self):
"""Copy the instance of evoked.
Returns
-------
evoked : instance of Evoked
A copy of the object.
"""
evoked = deepcopy(self)
return evoked
def __neg__(self):
"""Negate channel responses.
Returns
-------
evoked_neg : instance of Evoked
The Evoked instance with channel data negated and '-'
prepended to the comment.
"""
out = self.copy()
out.data *= -1
if out.comment is not None and " + " in out.comment:
out.comment = f"({out.comment})" # multiple conditions in evoked
out.comment = f"- {out.comment or 'unknown'}"
return out
def get_peak(
self,
ch_type=None,
tmin=None,
tmax=None,
mode="abs",
time_as_index=False,
merge_grads=False,
return_amplitude=False,
*,
strict=True,
):
"""Get location and latency of peak amplitude.
Parameters
----------
ch_type : str | None
The channel type to use. Defaults to None. If more than one channel
type is present in the data, this value **must** be provided.
tmin : float | None
The minimum point in time to be considered for peak getting.
If None (default), the beginning of the data is used.
tmax : float | None
The maximum point in time to be considered for peak getting.
If None (default), the end of the data is used.
mode : 'pos' | 'neg' | 'abs'
How to deal with the sign of the data. If 'pos' only positive
values will be considered. If 'neg' only negative values will
be considered. If 'abs' absolute values will be considered.
Defaults to 'abs'.
time_as_index : bool
Whether to return the time index instead of the latency in seconds.
merge_grads : bool
If True, compute peak from merged gradiometer data.
return_amplitude : bool
If True, return also the amplitude at the maximum response.
.. versionadded:: 0.16
strict : bool
If True, raise an error if values are all positive when detecting
a minimum (mode='neg'), or all negative when detecting a maximum
(mode='pos'). Defaults to True.
.. versionadded:: 1.7
Returns
-------
ch_name : str
The channel exhibiting the maximum response.
latency : float | int
The time point of the maximum response, either latency in seconds
or index.
amplitude : float
The amplitude of the maximum response. Only returned if
return_amplitude is True.
.. versionadded:: 0.16
""" # noqa: E501
supported = (
"mag",
"grad",
"eeg",
"seeg",
"dbs",
"ecog",
"misc",
"None",
) + _FNIRS_CH_TYPES_SPLIT
types_used = self.get_channel_types(unique=True, only_data_chs=True)
_check_option("ch_type", str(ch_type), supported)
if ch_type is not None and ch_type not in types_used:
raise ValueError(
f'Channel type "{ch_type}" not found in this evoked object.'
)
elif len(types_used) > 1 and ch_type is None:
raise RuntimeError(
'Multiple data channel types found. Please pass the "ch_type" '
"parameter."
)
if merge_grads:
if ch_type != "grad":
raise ValueError('Channel type must be "grad" for merge_grads')
elif mode == "neg":
raise ValueError(
"Negative mode (mode=neg) does not make sense with merge_grads=True"
)
meg = eeg = misc = seeg = dbs = ecog = fnirs = False
picks = None
if ch_type in ("mag", "grad"):
meg = ch_type
elif ch_type == "eeg":
eeg = True
elif ch_type == "misc":
misc = True
elif ch_type == "seeg":
seeg = True
elif ch_type == "dbs":
dbs = True
elif ch_type == "ecog":
ecog = True
elif ch_type in _FNIRS_CH_TYPES_SPLIT:
fnirs = ch_type
if ch_type is not None:
if merge_grads:
picks = _pair_grad_sensors(self.info, topomap_coords=False)
else:
picks = pick_types(
self.info,
meg=meg,
eeg=eeg,
misc=misc,
seeg=seeg,
ecog=ecog,
ref_meg=False,
fnirs=fnirs,
dbs=dbs,
)
data = self.data
ch_names = self.ch_names
if picks is not None:
data = data[picks]
ch_names = [ch_names[k] for k in picks]
if merge_grads:
data, _ = _merge_ch_data(data, ch_type, [])
ch_names = [ch_name[:-1] + "X" for ch_name in ch_names[::2]]
ch_idx, time_idx, max_amp = _get_peak(
data,
self.times,
tmin,
tmax,
mode,
strict=strict,
)
out = (ch_names[ch_idx], time_idx if time_as_index else self.times[time_idx])
if return_amplitude:
out += (max_amp,)
return out
@verbose
def compute_psd(
self,
method="multitaper",
fmin=0,
fmax=np.inf,
tmin=None,
tmax=None,
picks=None,
proj=False,
remove_dc=True,
exclude=(),
*,
n_jobs=1,
verbose=None,
**method_kw,
):
"""Perform spectral analysis on sensor data.
Parameters
----------
%(method_psd)s
Default is ``'multitaper'``.
%(fmin_fmax_psd)s
%(tmin_tmax_psd)s
%(picks_good_data_noref)s
%(proj_psd)s
%(remove_dc)s
%(exclude_psd)s
%(n_jobs)s
%(verbose)s
%(method_kw_psd)s
Returns
-------
spectrum : instance of Spectrum
The spectral representation of the data.
Notes
-----
.. versionadded:: 1.2
References
----------
.. footbibliography::
"""
method = _validate_method(method, type(self).__name__)
self._set_legacy_nfft_default(tmin, tmax, method, method_kw)
return Spectrum(
self,
method=method,
fmin=fmin,
fmax=fmax,
tmin=tmin,
tmax=tmax,
picks=picks,
exclude=exclude,
proj=proj,
remove_dc=remove_dc,
reject_by_annotation=False,
n_jobs=n_jobs,
verbose=verbose,
**method_kw,
)
@verbose
def compute_tfr(
self,
method,
freqs,
*,
tmin=None,
tmax=None,
picks=None,
proj=False,
output="power",
decim=1,
n_jobs=None,
verbose=None,
**method_kw,
):
"""Compute a time-frequency representation of evoked data.
Parameters
----------
%(method_tfr)s
%(freqs_tfr)s
%(tmin_tmax_psd)s
%(picks_good_data_noref)s
%(proj_psd)s
%(output_compute_tfr)s
%(decim_tfr)s
%(n_jobs)s
%(verbose)s
%(method_kw_tfr)s
Returns
-------
tfr : instance of AverageTFR
The time-frequency-resolved power estimates of the data.
Notes
-----
.. versionadded:: 1.7
References
----------
.. footbibliography::
"""
_check_option("output", output, ("power", "phase", "complex"))
method_kw["output"] = output
return AverageTFR(
inst=self,
method=method,
freqs=freqs,
tmin=tmin,
tmax=tmax,
picks=picks,
proj=proj,
decim=decim,
n_jobs=n_jobs,
verbose=verbose,
**method_kw,
)
@verbose
def plot_psd(
self,
fmin=0,
fmax=np.inf,
tmin=None,
tmax=None,
picks=None,
proj=False,
*,
method="auto",
average=False,
dB=True,
estimate="power",
xscale="linear",
area_mode="std",
area_alpha=0.33,
color="black",
line_alpha=None,
spatial_colors=True,
sphere=None,
exclude="bads",
ax=None,
show=True,
n_jobs=1,
verbose=None,
**method_kw,
):
"""%(plot_psd_doc)s.
Parameters
----------
%(fmin_fmax_psd)s
%(tmin_tmax_psd)s
%(picks_good_data_noref)s
%(proj_psd)s
%(method_plot_psd_auto)s
%(average_plot_psd)s
%(dB_plot_psd)s
%(estimate_plot_psd)s
%(xscale_plot_psd)s
%(area_mode_plot_psd)s
%(area_alpha_plot_psd)s
%(color_plot_psd)s
%(line_alpha_plot_psd)s
%(spatial_colors_psd)s
%(sphere_topomap_auto)s
.. versionadded:: 0.22.0
exclude : list of str | 'bads'
Channels names to exclude from being shown. If 'bads', the bad
channels are excluded. Pass an empty list to plot all channels
(including channels marked "bad", if any).
.. versionadded:: 0.24.0
%(ax_plot_psd)s
%(show)s
%(n_jobs)s
%(verbose)s
%(method_kw_psd)s
Returns
-------
fig : instance of Figure
Figure with frequency spectra of the data channels.
Notes
-----
%(notes_plot_psd_meth)s
"""
return super().plot_psd(
fmin=fmin,
fmax=fmax,
tmin=tmin,
tmax=tmax,
picks=picks,
proj=proj,
reject_by_annotation=False,
method=method,
average=average,
dB=dB,
estimate=estimate,
xscale=xscale,
area_mode=area_mode,
area_alpha=area_alpha,
color=color,
line_alpha=line_alpha,
spatial_colors=spatial_colors,
sphere=sphere,
exclude=exclude,
ax=ax,
show=show,
n_jobs=n_jobs,
verbose=verbose,
**method_kw,
)
@verbose
def to_data_frame(
self,
picks=None,
index=None,
scalings=None,
copy=True,
long_format=False,
time_format=None,
*,
verbose=None,
):
"""Export data in tabular structure as a pandas DataFrame.
Channels are converted to columns in the DataFrame. By default,
an additional column "time" is added, unless ``index='time'``
(in which case time values form the DataFrame's index).
Parameters
----------
%(picks_all)s
%(index_df_evk)s
Defaults to ``None``.
%(scalings_df)s
%(copy_df)s
%(long_format_df_raw)s
%(time_format_df)s
.. versionadded:: 0.20
%(verbose)s
Returns
-------
%(df_return)s
"""
# check pandas once here, instead of in each private utils function
pd = _check_pandas_installed() # noqa
# arg checking
valid_index_args = ["time"]
valid_time_formats = ["ms", "timedelta"]
index = _check_pandas_index_arguments(index, valid_index_args)
time_format = _check_time_format(time_format, valid_time_formats)
# get data
picks = _picks_to_idx(self.info, picks, "all", exclude=())
data = self.data[picks, :]
times = self.times
data = data.T
if copy:
data = data.copy()
data = _scale_dataframe_data(self, data, picks, scalings)
# prepare extra columns / multiindex
mindex = list()
times = _convert_times(times, time_format, self.info["meas_date"])
mindex.append(("time", times))
# build DataFrame
df = _build_data_frame(
self, data, picks, long_format, mindex, index, default_index=["time"]
)
return df
@fill_doc
class EvokedArray(Evoked):
"""Evoked object from numpy array.
Parameters
----------
data : array of shape (n_channels, n_times)
The channels' evoked response. See notes for proper units of measure.
%(info_not_none)s Consider using :func:`mne.create_info` to populate this
structure.
tmin : float
Start time before event. Defaults to 0.
comment : str
Comment on dataset. Can be the condition. Defaults to ''.
nave : int
Number of averaged epochs. Defaults to 1.
kind : str
Type of data, either average or standard_error. Defaults to 'average'.
%(baseline_evoked)s
Defaults to ``None``, i.e. no baseline correction.
.. versionadded:: 0.23
%(verbose)s
See Also
--------
EpochsArray, io.RawArray, create_info
Notes
-----
Proper units of measure:
* V: eeg, eog, seeg, dbs, emg, ecg, bio, ecog
* T: mag
* T/m: grad
* M: hbo, hbr
* Am: dipole
* AU: misc
"""
@verbose
def __init__(
self,
data,
info,
tmin=0.0,
comment="",
nave=1,
kind="average",
baseline=None,
*,
verbose=None,
):
dtype = np.complex128 if np.iscomplexobj(data) else np.float64
data = np.asanyarray(data, dtype=dtype)
if data.ndim != 2:
raise ValueError(
"Data must be a 2D array of shape (n_channels, n_samples), got shape "
f"{data.shape}"
)
if len(info["ch_names"]) != np.shape(data)[0]:
raise ValueError(
f"Info ({len(info['ch_names'])}) and data ({np.shape(data)[0]}) must "
"have same number of channels."
)
self.data = data
self.first = int(round(tmin * info["sfreq"]))
self.last = self.first + np.shape(data)[-1] - 1
self._set_times(
np.arange(self.first, self.last + 1, dtype=np.float64) / info["sfreq"]
)
self._raw_times = self.times.copy()
self._decim = 1
self.info = info.copy() # do not modify original info
self.nave = nave
self.kind = kind
self.comment = comment
self.picks = None
self.preload = True
self._projector = None
_validate_type(self.kind, "str", "kind")
if self.kind not in _aspect_dict:
raise ValueError(
f'unknown kind "{self.kind}", should be "average" or "standard_error"'
)
self._aspect_kind = _aspect_dict[self.kind]
self.baseline = baseline
if self.baseline is not None: # omit log msg if not baselining
self.apply_baseline(self.baseline)
self._filename = None
def _get_entries(fid, evoked_node, allow_maxshield=False):
"""Get all evoked entries."""
comments = list()
aspect_kinds = list()
for ev in evoked_node:
for k in range(ev["nent"]):
my_kind = ev["directory"][k].kind
pos = ev["directory"][k].pos
if my_kind == FIFF.FIFF_COMMENT:
tag = read_tag(fid, pos)
comments.append(tag.data)
my_aspect = _get_aspect(ev, allow_maxshield)[0]
for k in range(my_aspect["nent"]):
my_kind = my_aspect["directory"][k].kind
pos = my_aspect["directory"][k].pos
if my_kind == FIFF.FIFF_ASPECT_KIND:
tag = read_tag(fid, pos)
aspect_kinds.append(int(tag.data.item()))
comments = np.atleast_1d(comments)
aspect_kinds = np.atleast_1d(aspect_kinds)
if len(comments) != len(aspect_kinds) or len(comments) == 0:
fid.close()
raise ValueError("Dataset names in FIF file could not be found.")
t = [_aspect_rev[a] for a in aspect_kinds]
t = ['"' + c + '" (' + tt + ")" for tt, c in zip(t, comments)]
t = "\n".join(t)
return comments, aspect_kinds, t
def _get_aspect(evoked, allow_maxshield):
"""Get Evoked data aspect."""
from .io.base import _check_maxshield
is_maxshield = False
aspect = dir_tree_find(evoked, FIFF.FIFFB_ASPECT)
if len(aspect) == 0:
_check_maxshield(allow_maxshield)
aspect = dir_tree_find(evoked, FIFF.FIFFB_IAS_ASPECT)
is_maxshield = True
if len(aspect) > 1:
logger.info("Multiple data aspects found. Taking first one.")
return aspect[0], is_maxshield
def _get_evoked_node(fname):
"""Get info in evoked file."""
f, tree, _ = fiff_open(fname)
with f as fid:
_, meas = read_meas_info(fid, tree, verbose=False)
evoked_node = dir_tree_find(meas, FIFF.FIFFB_EVOKED)
return evoked_node
def _check_evokeds_ch_names_times(all_evoked):
evoked = all_evoked[0]
ch_names = evoked.ch_names
for ii, ev in enumerate(all_evoked[1:]):
if ev.ch_names != ch_names:
if set(ev.ch_names) != set(ch_names):
raise ValueError(f"{evoked} and {ev} do not contain the same channels.")
else:
warn("Order of channels differs, reordering channels ...")
ev = ev.copy()
ev.reorder_channels(ch_names)
all_evoked[ii + 1] = ev
if not np.max(np.abs(ev.times - evoked.times)) < 1e-7:
raise ValueError(f"{evoked} and {ev} do not contain the same time instants")
return all_evoked
def combine_evoked(all_evoked, weights):
"""Merge evoked data by weighted addition or subtraction.
Each `~mne.Evoked` in ``all_evoked`` should have the same channels and the
same time instants. Subtraction can be performed by passing
``weights=[1, -1]``.
.. Warning::
Other than cases like simple subtraction mentioned above (where all
weights are ``-1`` or ``1``), if you provide numeric weights instead of using
``'equal'`` or ``'nave'``, the resulting `~mne.Evoked` object's
``.nave`` attribute (which is used to scale noise covariance when
applying the inverse operator) may not be suitable for inverse imaging.
Parameters
----------
all_evoked : list of Evoked
The evoked datasets.
weights : list of float | ``'equal'`` | ``'nave'``
The weights to apply to the data of each evoked instance, or a string
describing the weighting strategy to apply: ``'nave'`` computes
sum-to-one weights proportional to each object's ``nave`` attribute;
``'equal'`` weights each `~mne.Evoked` by ``1 / len(all_evoked)``.
Returns
-------
evoked : Evoked
The new evoked data.
Notes
-----
.. versionadded:: 0.9.0
"""
naves = np.array([evk.nave for evk in all_evoked], float)
if isinstance(weights, str):
_check_option("weights", weights, ["nave", "equal"])
if weights == "nave":
weights = naves / naves.sum()
else:
weights = np.ones_like(naves) / len(naves)
else:
weights = np.array(weights, float)
if weights.ndim != 1 or weights.size != len(all_evoked):
raise ValueError("weights must be the same size as all_evoked")
# cf. https://en.wikipedia.org/wiki/Weighted_arithmetic_mean, section on
# "weighted sample variance". The variance of a weighted sample mean is:
#
# σ² = w₁² σ₁² + w₂² σ₂² + ... + wₙ² σₙ²
#
# We estimate the variance of each evoked instance as 1 / nave to get:
#
# σ² = w₁² / nave₁ + w₂² / nave₂ + ... + wₙ² / naveₙ
#
# And our resulting nave is the reciprocal of this:
new_nave = 1.0 / np.sum(weights**2 / naves)
# This general formula is equivalent to formulae in Matti's manual
# (pp 128-129), where:
# new_nave = sum(naves) when weights='nave' and
# new_nave = 1. / sum(1. / naves) when weights are all 1.
all_evoked = _check_evokeds_ch_names_times(all_evoked)
evoked = all_evoked[0].copy()
# use union of bad channels
bads = list(set(b for e in all_evoked for b in e.info["bads"]))
evoked.info["bads"] = bads
evoked.data = sum(w * e.data for w, e in zip(weights, all_evoked))
evoked.nave = new_nave
comment = ""
for idx, (w, e) in enumerate(zip(weights, all_evoked)):
# pick sign
sign = "" if w >= 0 else "-"
# format weight
weight = "" if np.isclose(abs(w), 1.0) else f"{abs(w):0.3f}"
# format multiplier
multiplier = " × " if weight else ""
# format comment
if e.comment is not None and " + " in e.comment: # multiple conditions
this_comment = f"({e.comment})"
else:
this_comment = f"{e.comment or 'unknown'}"
# assemble everything
if idx == 0:
comment += f"{sign}{weight}{multiplier}{this_comment}"
else:
comment += f" {sign or '+'} {weight}{multiplier}{this_comment}"
# special-case: combine_evoked([e1, -e2], [1, -1])
evoked.comment = comment.replace(" - - ", " + ")
return evoked
@verbose
def read_evokeds(
fname,
condition=None,
baseline=None,
kind="average",
proj=True,
allow_maxshield=False,
verbose=None,
) -> list[Evoked] | Evoked:
"""Read evoked dataset(s).
Parameters
----------
fname : path-like
The filename, which should end with ``-ave.fif`` or ``-ave.fif.gz``.
condition : int or str | list of int or str | None
The index or list of indices of the evoked dataset to read. FIF files
can contain multiple datasets. If None, all datasets are returned as a
list.
%(baseline_evoked)s
If ``None`` (default), do not apply baseline correction.
.. note:: Note that if the read `~mne.Evoked` objects have already
been baseline-corrected, the data retrieved from disk will
**always** be baseline-corrected (in fact, only the
baseline-corrected version of the data will be saved, so
there is no way to undo this procedure). Only **after** the
data has been loaded, a custom (additional) baseline
correction **may** be optionally applied by passing a tuple
here. Passing ``None`` will **not** remove an existing
baseline correction, but merely omit the optional, additional
baseline correction.
kind : str
Either ``'average'`` or ``'standard_error'``, the type of data to read.
proj : bool
If False, available projectors won't be applied to the data.
allow_maxshield : bool | str (default False)
If True, allow loading of data that has been recorded with internal
active compensation (MaxShield). Data recorded with MaxShield should
generally not be loaded directly, but should first be processed using
SSS/tSSS to remove the compensation signals that may also affect brain
activity. Can also be ``"yes"`` to load without eliciting a warning.
%(verbose)s
Returns
-------
evoked : Evoked or list of Evoked
The evoked dataset(s); one `~mne.Evoked` if ``condition`` is an
integer or string; or a list of `~mne.Evoked` if ``condition`` is
``None`` or a list.
See Also
--------
write_evokeds
Notes
-----
.. versionchanged:: 0.23
If the read `~mne.Evoked` objects had been baseline-corrected before
saving, this will be reflected in their ``baseline`` attribute after
reading.
"""
fname = _check_fname(fname, overwrite="read", must_exist=True)
check_fname(fname, "evoked", ("-ave.fif", "-ave.fif.gz", "_ave.fif", "_ave.fif.gz"))
logger.info(f"Reading {fname} ...")
return_list = True
if condition is None:
evoked_node = _get_evoked_node(fname)
condition = range(len(evoked_node))
elif not isinstance(condition, list):
condition = [condition]
return_list = False
out = []
for c in condition:
evoked = Evoked(
fname,
c,
kind=kind,
proj=proj,
allow_maxshield=allow_maxshield,
verbose=verbose,
)
if baseline is None and evoked.baseline is None:
logger.info(_log_rescale(None))
elif baseline is None and evoked.baseline is not None:
# Don't touch an existing baseline
bmin, bmax = evoked.baseline
logger.info(
f"Loaded Evoked data is baseline-corrected "
f"(baseline: [{bmin:g}, {bmax:g}] s)"
)
else:
evoked.apply_baseline(baseline)
out.append(evoked)
return out if return_list else out[0]
def _read_evoked(fname, condition=None, kind="average", allow_maxshield=False):
"""Read evoked data from a FIF file."""
if fname is None:
raise ValueError("No evoked filename specified")
f, tree, _ = fiff_open(fname)
with f as fid:
# Read the measurement info
info, meas = read_meas_info(fid, tree, clean_bads=True)
# Locate the data of interest
processed = dir_tree_find(meas, FIFF.FIFFB_PROCESSED_DATA)
if len(processed) == 0:
raise ValueError("Could not find processed data")
evoked_node = dir_tree_find(meas, FIFF.FIFFB_EVOKED)
if len(evoked_node) == 0:
raise ValueError("Could not find evoked data")
# find string-based entry
if isinstance(condition, str):
if kind not in _aspect_dict.keys():
raise ValueError('kind must be "average" or "standard_error"')
comments, aspect_kinds, t = _get_entries(fid, evoked_node, allow_maxshield)
goods = np.isin(comments, [condition]) & np.isin(
aspect_kinds, [_aspect_dict[kind]]
)
found_cond = np.where(goods)[0]
if len(found_cond) != 1:
raise ValueError(
f'condition "{condition}" ({kind}) not found, out of found '
f"datasets:\n{t}"
)
condition = found_cond[0]
elif condition is None:
if len(evoked_node) > 1:
_, _, conditions = _get_entries(fid, evoked_node, allow_maxshield)
raise TypeError(
"Evoked file has more than one condition, the condition parameters "
f"must be specified from:\n{conditions}"
)
else:
condition = 0
if condition >= len(evoked_node) or condition < 0:
raise ValueError("Data set selector out of range")
my_evoked = evoked_node[condition]
# Identify the aspects
with info._unlock():
my_aspect, info["maxshield"] = _get_aspect(my_evoked, allow_maxshield)
# Now find the data in the evoked block
nchan = 0
sfreq = -1
chs = []
baseline = bmin = bmax = None
comment = last = first = first_time = nsamp = None
for k in range(my_evoked["nent"]):
my_kind = my_evoked["directory"][k].kind
pos = my_evoked["directory"][k].pos
if my_kind == FIFF.FIFF_COMMENT:
tag = read_tag(fid, pos)
comment = tag.data
elif my_kind == FIFF.FIFF_FIRST_SAMPLE:
tag = read_tag(fid, pos)
first = int(tag.data.item())
elif my_kind == FIFF.FIFF_LAST_SAMPLE:
tag = read_tag(fid, pos)
last = int(tag.data.item())
elif my_kind == FIFF.FIFF_NCHAN:
tag = read_tag(fid, pos)
nchan = int(tag.data.item())
elif my_kind == FIFF.FIFF_SFREQ:
tag = read_tag(fid, pos)
sfreq = float(tag.data.item())
elif my_kind == FIFF.FIFF_CH_INFO:
tag = read_tag(fid, pos)
chs.append(tag.data)
elif my_kind == FIFF.FIFF_FIRST_TIME:
tag = read_tag(fid, pos)
first_time = float(tag.data.item())
elif my_kind == FIFF.FIFF_NO_SAMPLES:
tag = read_tag(fid, pos)
nsamp = int(tag.data.item())
elif my_kind == FIFF.FIFF_MNE_BASELINE_MIN:
tag = read_tag(fid, pos)
bmin = float(tag.data.item())
elif my_kind == FIFF.FIFF_MNE_BASELINE_MAX:
tag = read_tag(fid, pos)
bmax = float(tag.data.item())
if comment is None:
comment = "No comment"
if bmin is not None or bmax is not None:
# None's should've been replaced with floats
assert bmin is not None and bmax is not None
baseline = (bmin, bmax)
# Local channel information?
if nchan > 0:
if chs is None:
raise ValueError(
"Local channel information was not found when it was expected."
)
if len(chs) != nchan:
raise ValueError(
"Number of channels and number of channel definitions are different"
)
ch_names_mapping = _read_extended_ch_info(chs, my_evoked, fid)
info["chs"] = chs
info["bads"][:] = _rename_list(info["bads"], ch_names_mapping)
logger.info(
f" Found channel information in evoked data. nchan = {nchan}"
)
if sfreq > 0:
info["sfreq"] = sfreq
# Read the data in the aspect block
nave = 1
epoch = []
for k in range(my_aspect["nent"]):
kind = my_aspect["directory"][k].kind
pos = my_aspect["directory"][k].pos
if kind == FIFF.FIFF_COMMENT:
tag = read_tag(fid, pos)
comment = tag.data
elif kind == FIFF.FIFF_ASPECT_KIND:
tag = read_tag(fid, pos)
aspect_kind = int(tag.data.item())
elif kind == FIFF.FIFF_NAVE:
tag = read_tag(fid, pos)
nave = int(tag.data.item())
elif kind == FIFF.FIFF_EPOCH:
tag = read_tag(fid, pos)
epoch.append(tag)
nepoch = len(epoch)
if nepoch != 1 and nepoch != info["nchan"]:
raise ValueError(
"Number of epoch tags is unreasonable "
f"(nepoch = {nepoch} nchan = {info['nchan']})"
)
if nepoch == 1:
# Only one epoch
data = epoch[0].data
# May need a transpose if the number of channels is one
if data.shape[1] == 1 and info["nchan"] == 1:
data = data.T
else:
# Put the old style epochs together
data = np.concatenate([e.data[None, :] for e in epoch], axis=0)
if np.isrealobj(data):
data = data.astype(np.float64)
else:
data = data.astype(np.complex128)
if first_time is not None and nsamp is not None:
times = first_time + np.arange(nsamp) / info["sfreq"]
elif first is not None:
nsamp = last - first + 1
times = np.arange(first, last + 1) / info["sfreq"]
else:
raise RuntimeError("Could not read time parameters")
del first, last
if nsamp is not None and data.shape[1] != nsamp:
raise ValueError(
f"Incorrect number of samples ({data.shape[1]} instead of {nsamp})"
)
logger.info(" Found the data of interest:")
logger.info(
f" t = {1000 * times[0]:10.2f} ... {1000 * times[-1]:10.2f} ms ("
f"{comment})"
)
if info["comps"] is not None:
logger.info(
f" {len(info['comps'])} CTF compensation matrices available"
)
logger.info(f" nave = {nave} - aspect type = {aspect_kind}")
# Calibrate
cals = np.array(
[
info["chs"][k]["cal"] * info["chs"][k].get("scale", 1.0)
for k in range(info["nchan"])
]
)
data *= cals[:, np.newaxis]
return info, nave, aspect_kind, comment, times, data, baseline
@verbose
def write_evokeds(fname, evoked, *, on_mismatch="raise", overwrite=False, verbose=None):
"""Write an evoked dataset to a file.
Parameters
----------
fname : path-like
The file name, which should end with ``-ave.fif`` or ``-ave.fif.gz``.
evoked : Evoked instance, or list of Evoked instances
The evoked dataset, or list of evoked datasets, to save in one file.
Note that the measurement info from the first evoked instance is used,
so be sure that information matches.
%(on_mismatch_info)s
%(overwrite)s
.. versionadded:: 1.0
%(verbose)s
.. versionadded:: 0.24
See Also
--------
read_evokeds
Notes
-----
.. versionchanged:: 0.23
Information on baseline correction will be stored with each individual
`~mne.Evoked` object, and will be restored when reading the data again
via `mne.read_evokeds`.
"""
_write_evokeds(fname, evoked, on_mismatch=on_mismatch, overwrite=overwrite)
def _write_evokeds(fname, evoked, check=True, *, on_mismatch="raise", overwrite=False):
"""Write evoked data."""
from .dipole import DipoleFixed # avoid circular import
fname = _check_fname(fname=fname, overwrite=overwrite)
if check:
check_fname(
fname, "evoked", ("-ave.fif", "-ave.fif.gz", "_ave.fif", "_ave.fif.gz")
)
if not isinstance(evoked, list | tuple):
evoked = [evoked]
warned = False
# Create the file and save the essentials
with start_and_end_file(fname) as fid:
start_block(fid, FIFF.FIFFB_MEAS)
write_id(fid, FIFF.FIFF_BLOCK_ID)
if evoked[0].info["meas_id"] is not None:
write_id(fid, FIFF.FIFF_PARENT_BLOCK_ID, evoked[0].info["meas_id"])
# Write measurement info
write_meas_info(fid, evoked[0].info)
# One or more evoked data sets
start_block(fid, FIFF.FIFFB_PROCESSED_DATA)
for ei, e in enumerate(evoked):
if ei:
_ensure_infos_match(
info1=evoked[0].info,
info2=e.info,
name=f"evoked[{ei}]",
on_mismatch=on_mismatch,
)
start_block(fid, FIFF.FIFFB_EVOKED)
# Comment is optional
if e.comment is not None and len(e.comment) > 0:
write_string(fid, FIFF.FIFF_COMMENT, e.comment)
# First time, num. samples, first and last sample
write_float(fid, FIFF.FIFF_FIRST_TIME, e.times[0])
write_int(fid, FIFF.FIFF_NO_SAMPLES, len(e.times))
write_int(fid, FIFF.FIFF_FIRST_SAMPLE, e.first)
write_int(fid, FIFF.FIFF_LAST_SAMPLE, e.last)
# Baseline
if not isinstance(e, DipoleFixed) and e.baseline is not None:
bmin, bmax = e.baseline
write_float(fid, FIFF.FIFF_MNE_BASELINE_MIN, bmin)
write_float(fid, FIFF.FIFF_MNE_BASELINE_MAX, bmax)
# The evoked data itself
if e.info.get("maxshield"):
aspect = FIFF.FIFFB_IAS_ASPECT
else:
aspect = FIFF.FIFFB_ASPECT
start_block(fid, aspect)
write_int(fid, FIFF.FIFF_ASPECT_KIND, e._aspect_kind)
# convert nave to integer to comply with FIFF spec
nave_int = int(round(e.nave))
if nave_int != e.nave and not warned:
warn(
'converting "nave" to integer before saving evoked; this '
"can have a minor effect on the scale of source "
'estimates that are computed using "nave".'
)
warned = True
write_int(fid, FIFF.FIFF_NAVE, nave_int)
del nave_int
decal = np.zeros((e.info["nchan"], 1))
for k in range(e.info["nchan"]):
decal[k] = 1.0 / (
e.info["chs"][k]["cal"] * e.info["chs"][k].get("scale", 1.0)
)
if np.iscomplexobj(e.data):
write_function = write_complex_float_matrix
else:
write_function = write_float_matrix
write_function(fid, FIFF.FIFF_EPOCH, decal * e.data)
end_block(fid, aspect)
end_block(fid, FIFF.FIFFB_EVOKED)
end_block(fid, FIFF.FIFFB_PROCESSED_DATA)
end_block(fid, FIFF.FIFFB_MEAS)
def _get_peak(data, times, tmin=None, tmax=None, mode="abs", *, strict=True):
"""Get feature-index and time of maximum signal from 2D array.
Note. This is a 'getter', not a 'finder'. For non-evoked type
data and continuous signals, please use proper peak detection algorithms.
Parameters
----------
data : instance of numpy.ndarray (n_locations, n_times)
The data, either evoked in sensor or source space.
times : instance of numpy.ndarray (n_times)
The times in seconds.
tmin : float | None
The minimum point in time to be considered for peak getting.
tmax : float | None
The maximum point in time to be considered for peak getting.
mode : {'pos', 'neg', 'abs'}
How to deal with the sign of the data. If 'pos' only positive
values will be considered. If 'neg' only negative values will
be considered. If 'abs' absolute values will be considered.
Defaults to 'abs'.
strict : bool
If True, raise an error if values are all positive when detecting
a minimum (mode='neg'), or all negative when detecting a maximum
(mode='pos'). Defaults to True.
Returns
-------
max_loc : int
The index of the feature with the maximum value.
max_time : int
The time point of the maximum response, index.
max_amp : float
Amplitude of the maximum response.
"""
_check_option("mode", mode, ["abs", "neg", "pos"])
if tmin is None:
tmin = times[0]
if tmax is None:
tmax = times[-1]
if tmin < times.min() or tmax > times.max():
if tmin < times.min():
param_name = "tmin"
param_val = tmin
else:
param_name = "tmax"
param_val = tmax
raise ValueError(
f"{param_name} ({param_val}) is out of bounds. It must be "
f"between {times.min()} and {times.max()}"
)
elif tmin > tmax:
raise ValueError(f"tmin ({tmin}) must be <= tmax ({tmax})")
time_win = (times >= tmin) & (times <= tmax)
mask = np.ones_like(data).astype(bool)
mask[:, time_win] = False
maxfun = np.argmax
if mode == "pos":
if strict and not np.any(data[~mask] > 0):
raise ValueError(
"No positive values encountered. Cannot operate in pos mode."
)
elif mode == "neg":
if strict and not np.any(data[~mask] < 0):
raise ValueError(
"No negative values encountered. Cannot operate in neg mode."
)
maxfun = np.argmin
masked_index = np.ma.array(np.abs(data) if mode == "abs" else data, mask=mask)
max_loc, max_time = np.unravel_index(maxfun(masked_index), data.shape)
return max_loc, max_time, data[max_loc, max_time]