# # Authors: The MNE-Python contributors. # License: BSD-3-Clause # Copyright the MNE-Python contributors. from __future__ import annotations # only needed for Python ≤ 3.9 import json import math import warnings from collections import namedtuple from collections.abc import Sequence from copy import deepcopy from dataclasses import dataclass, is_dataclass from inspect import Parameter, isfunction, signature from numbers import Integral from time import time from typing import Literal import numpy as np from scipy import stats from scipy.spatial import distance from scipy.special import expit from .._fiff.constants import FIFF from .._fiff.meas_info import ContainsMixin, read_meas_info, write_meas_info from .._fiff.open import fiff_open from .._fiff.pick import ( _DATA_CH_TYPES_SPLIT, _contains_ch_type, _picks_by_type, _picks_to_idx, pick_channels, pick_channels_regexp, pick_info, pick_types, ) from .._fiff.proj import make_projector 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_double_matrix, write_id, write_int, write_name_list, write_string, ) from ..channels.layout import _find_topomap_coords from ..cov import Covariance, compute_whitener from ..defaults import _BORDER_DEFAULT, _EXTRAPOLATE_DEFAULT, _INTERPOLATION_DEFAULT from ..epochs import BaseEpochs from ..evoked import Evoked from ..filter import filter_data from ..fixes import _safe_svd from ..html_templates import _get_html_template from ..io import BaseRaw from ..io.eeglab.eeglab import _check_load_mat, _get_info from ..utils import ( _PCA, Bunch, _check_all_same_channel_names, _check_compensation_grade, _check_fname, _check_on_missing, _check_option, _check_preload, _ensure_int, _get_inst_data, _on_missing, _pl, _reject_data_segments, _require_version, _validate_type, check_fname, check_random_state, compute_corr, copy_function_doc_to_method_doc, fill_doc, int_like, logger, pinv, repr_html, verbose, warn, ) from ..viz import ( plot_ica_components, plot_ica_overlay, plot_ica_scores, plot_ica_sources, ) from ..viz.ica import plot_ica_properties from ..viz.topomap import _plot_corrmap from .bads import _find_outliers from .ctps_ import ctps from .ecg import _get_ecg_channel_index, _make_ecg, create_ecg_epochs, qrs_detector from .eog import _find_eog_events, _get_eog_channel_index from .infomax_ import infomax __all__ = ( "ICA", "ica_find_ecg_events", "ica_find_eog_events", "get_score_funcs", "read_ica", "read_ica_eeglab", ) def _make_xy_sfunc(func, ndim_output=False): """Aux function.""" def sfunc(x, y, ndim_output=ndim_output): out = [func(a, y.ravel()) for a in x] if len(out) and is_dataclass(out[0]): # PermutationTestResult out = [(o.statistic, o.pvalue) for o in out] if ndim_output: out = np.array(out)[:, 0] return out sfunc.__name__ = ".".join(["score_func", func.__module__, func.__name__]) sfunc.__doc__ = func.__doc__ return sfunc # Violate our assumption that the output is 1D so can't be used. # Could eventually be added but probably not worth the effort unless someone # requests it. _BLOCKLIST = {"somersd"} # makes score funcs attr accessible for users def get_score_funcs(): """Get the score functions. Returns ------- score_funcs : dict The score functions. """ score_funcs = Bunch() xy_arg_dist_funcs = [ (n, f) for n, f in vars(distance).items() if isfunction(f) and not n.startswith("_") and n not in _BLOCKLIST ] xy_arg_stats_funcs = [ (n, f) for n, f in vars(stats).items() if isfunction(f) and not n.startswith("_") and n not in _BLOCKLIST ] score_funcs.update( { n: _make_xy_sfunc(f) for n, f in xy_arg_dist_funcs if signature(f).parameters == ["u", "v"] } ) # In SciPy 1.9+, pearsonr has (x, y, *, alternative='two-sided'), so we # should just look at the positional_only and positional_or_keyword entries for n, f in xy_arg_stats_funcs: params = [ name for name, param in signature(f).parameters.items() if param.kind in (Parameter.POSITIONAL_ONLY, Parameter.POSITIONAL_OR_KEYWORD) ] if params == ["x", "y"]: score_funcs.update({n: _make_xy_sfunc(f, ndim_output=True)}) assert "pearsonr" in score_funcs return score_funcs def _check_for_unsupported_ica_channels(picks, info, allow_ref_meg=False): """Check for channels in picks that are not considered valid channels. Accepted channels are the data channels ('seeg', 'dbs', 'ecog', 'eeg', 'hbo', 'hbr', 'mag', and 'grad'), 'eog' and 'ref_meg'. This prevents the program from crashing without feedback when a bad channel is provided to ICA whitening. """ types = _DATA_CH_TYPES_SPLIT + ("eog",) types += ("ref_meg",) if allow_ref_meg else () chs = info.get_channel_types(picks, unique=True, only_data_chs=False) check = all([ch in types for ch in chs]) if not check: raise ValueError( f"Invalid channel type{_pl(chs)} passed for ICA: {chs}." f"Only the following types are supported: {types}" ) _KNOWN_ICA_METHODS = ("fastica", "infomax", "picard") @fill_doc class ICA(ContainsMixin): """Data decomposition using Independent Component Analysis (ICA). This object estimates independent components from :class:`mne.io.Raw`, :class:`mne.Epochs`, or :class:`mne.Evoked` objects. Components can optionally be removed (for artifact repair) prior to signal reconstruction. .. warning:: ICA is sensitive to low-frequency drifts and therefore requires the data to be high-pass filtered prior to fitting. Typically, a cutoff frequency of 1 Hz is recommended. Parameters ---------- n_components : int | float | None Number of principal components (from the pre-whitening PCA step) that are passed to the ICA algorithm during fitting: - :class:`int` Must be greater than 1 and less than or equal to the number of channels. - :class:`float` between 0 and 1 (exclusive) Will select the smallest number of components required to explain the cumulative variance of the data greater than ``n_components``. Consider this hypothetical example: we have 3 components, the first explaining 70%%, the second 20%%, and the third the remaining 10%% of the variance. Passing 0.8 here (corresponding to 80%% of explained variance) would yield the first two components, explaining 90%% of the variance: only by using both components the requested threshold of 80%% explained variance can be exceeded. The third component, on the other hand, would be excluded. - ``None`` ``0.999999`` will be used. This is done to avoid numerical stability problems when whitening, particularly when working with rank-deficient data. Defaults to ``None``. The actual number used when executing the :meth:`ICA.fit` method will be stored in the attribute ``n_components_`` (note the trailing underscore). .. versionchanged:: 0.22 For a :class:`python:float`, the number of components will account for *greater than* the given variance level instead of *less than or equal to* it. The default (None) will also take into account the rank deficiency of the data. noise_cov : None | instance of Covariance Noise covariance used for pre-whitening. If None (default), channels are scaled to unit variance ("z-standardized") as a group by channel type prior to the whitening by PCA. %(random_state)s method : 'fastica' | 'infomax' | 'picard' The ICA method to use in the fit method. Use the ``fit_params`` argument to set additional parameters. Specifically, if you want Extended Infomax, set ``method='infomax'`` and ``fit_params=dict(extended=True)`` (this also works for ``method='picard'``). Defaults to ``'fastica'``. For reference, see :footcite:`Hyvarinen1999,BellSejnowski1995,LeeEtAl1999,AblinEtAl2018`. fit_params : dict | None Additional parameters passed to the ICA estimator as specified by ``method``. Allowed entries are determined by the various algorithm implementations: see :class:`~sklearn.decomposition.FastICA`, :func:`~picard.picard`, :func:`~mne.preprocessing.infomax`. max_iter : int | 'auto' Maximum number of iterations during fit. If ``'auto'``, it will set maximum iterations to ``1000`` for ``'fastica'`` and to ``500`` for ``'infomax'`` or ``'picard'``. The actual number of iterations it took :meth:`ICA.fit` to complete will be stored in the ``n_iter_`` attribute. allow_ref_meg : bool Allow ICA on MEG reference channels. Defaults to False. .. versionadded:: 0.18 %(verbose)s Attributes ---------- current_fit : 'unfitted' | 'raw' | 'epochs' Which data type was used for the fit. ch_names : list-like Channel names resulting from initial picking. n_components_ : int If fit, the actual number of PCA components used for ICA decomposition. pre_whitener_ : ndarray, shape (n_channels, 1) or (n_channels, n_channels) If fit, array used to pre-whiten the data prior to PCA. pca_components_ : ndarray, shape ``(n_channels, n_channels)`` If fit, the PCA components. pca_mean_ : ndarray, shape (n_channels,) If fit, the mean vector used to center the data before doing the PCA. pca_explained_variance_ : ndarray, shape ``(n_channels,)`` If fit, the variance explained by each PCA component. mixing_matrix_ : ndarray, shape ``(n_components_, n_components_)`` If fit, the whitened mixing matrix to go back from ICA space to PCA space. It is, in combination with the ``pca_components_``, used by :meth:`ICA.apply` and :meth:`ICA.get_components` to re-mix/project a subset of the ICA components into the observed channel space. The former method also removes the pre-whitening (z-scaling) and the de-meaning. unmixing_matrix_ : ndarray, shape ``(n_components_, n_components_)`` If fit, the whitened matrix to go from PCA space to ICA space. Used, in combination with the ``pca_components_``, by the methods :meth:`ICA.get_sources` and :meth:`ICA.apply` to unmix the observed data. exclude : array-like of int List or np.array of sources indices to exclude when re-mixing the data in the :meth:`ICA.apply` method, i.e. artifactual ICA components. The components identified manually and by the various automatic artifact detection methods should be (manually) appended (e.g. ``ica.exclude.extend(eog_inds)``). (There is also an ``exclude`` parameter in the :meth:`ICA.apply` method.) To scrap all marked components, set this attribute to an empty list. %(info)s n_samples_ : int The number of samples used on fit. labels_ : dict A dictionary of independent component indices, grouped by types of independent components. This attribute is set by some of the artifact detection functions. n_iter_ : int If fit, the number of iterations required to complete ICA. Notes ----- .. versionchanged:: 0.23 Version 0.23 introduced the ``max_iter='auto'`` settings for maximum iterations. With version 0.24 ``'auto'`` will be the new default, replacing the current ``max_iter=200``. .. versionchanged:: 0.23 Warn if `~mne.Epochs` were baseline-corrected. .. note:: If you intend to fit ICA on `~mne.Epochs`, it is recommended to high-pass filter, but **not** baseline correct the data for good ICA performance. A warning will be emitted otherwise. A trailing ``_`` in an attribute name signifies that the attribute was added to the object during fitting, consistent with standard scikit-learn practice. ICA :meth:`fit` in MNE proceeds in two steps: 1. :term:`Whitening ` the data by means of a pre-whitening step (using ``noise_cov`` if provided, or the standard deviation of each channel type) and then principal component analysis (PCA). 2. Passing the ``n_components`` largest-variance components to the ICA algorithm to obtain the unmixing matrix (and by pseudoinversion, the mixing matrix). ICA :meth:`apply` then: 1. Unmixes the data with the ``unmixing_matrix_``. 2. Includes ICA components based on ``ica.include`` and ``ica.exclude``. 3. Re-mixes the data with ``mixing_matrix_``. 4. Restores any data not passed to the ICA algorithm, i.e., the PCA components between ``n_components`` and ``n_pca_components``. ``n_pca_components`` determines how many PCA components will be kept when reconstructing the data when calling :meth:`apply`. This parameter can be used for dimensionality reduction of the data, or dealing with low-rank data (such as those with projections, or MEG data processed by SSS). It is important to remove any numerically-zero-variance components in the data, otherwise numerical instability causes problems when computing the mixing matrix. Alternatively, using ``n_components`` as a float will also avoid numerical stability problems. The ``n_components`` parameter determines how many components out of the ``n_channels`` PCA components the ICA algorithm will actually fit. This is not typically used for EEG data, but for MEG data, it's common to use ``n_components < n_channels``. For example, full-rank 306-channel MEG data might use ``n_components=40`` to find (and later exclude) only large, dominating artifacts in the data, but still reconstruct the data using all 306 PCA components. Setting ``n_pca_components=40``, on the other hand, would actually reduce the rank of the reconstructed data to 40, which is typically undesirable. If you are migrating from EEGLAB and intend to reduce dimensionality via PCA, similarly to EEGLAB's ``runica(..., 'pca', n)`` functionality, pass ``n_components=n`` during initialization and then ``n_pca_components=n`` during :meth:`apply`. The resulting reconstructed data after :meth:`apply` will have rank ``n``. .. note:: Commonly used for reasons of i) computational efficiency and ii) additional noise reduction, it is a matter of current debate whether pre-ICA dimensionality reduction could decrease the reliability and stability of the ICA, at least for EEG data and especially during preprocessing :footcite:`ArtoniEtAl2018`. (But see also :footcite:`Montoya-MartinezEtAl2017` for a possibly confounding effect of the different whitening/sphering methods used in this paper (ZCA vs. PCA).) On the other hand, for rank-deficient data such as EEG data after average reference or interpolation, it is recommended to reduce the dimensionality (by 1 for average reference and 1 for each interpolated channel) for optimal ICA performance (see the `EEGLAB wiki `_). Caveat! If supplying a noise covariance, keep track of the projections available in the cov or in the raw object. For example, if you are interested in EOG or ECG artifacts, EOG and ECG projections should be temporally removed before fitting ICA, for example:: >> projs, raw.info['projs'] = raw.info['projs'], [] >> ica.fit(raw) >> raw.info['projs'] = projs Methods currently implemented are FastICA (default), Infomax, and Picard. Standard Infomax can be quite sensitive to differences in floating point arithmetic. Extended Infomax seems to be more stable in this respect, enhancing reproducibility and stability of results; use Extended Infomax via ``method='infomax', fit_params=dict(extended=True)``. Allowed entries in ``fit_params`` are determined by the various algorithm implementations: see :class:`~sklearn.decomposition.FastICA`, :func:`~picard.picard`, :func:`~mne.preprocessing.infomax`. .. note:: Picard can be used to solve the same problems as FastICA, Infomax, and extended Infomax, but typically converges faster than either of those methods. To make use of Picard's speed while still obtaining the same solution as with other algorithms, you need to specify ``method='picard'`` and ``fit_params`` as a dictionary with the following combination of keys: - ``dict(ortho=False, extended=False)`` for Infomax - ``dict(ortho=False, extended=True)`` for extended Infomax - ``dict(ortho=True, extended=True)`` for FastICA Reducing the tolerance (set in ``fit_params``) speeds up estimation at the cost of consistency of the obtained results. It is difficult to directly compare tolerance levels between Infomax and Picard, but for Picard and FastICA a good rule of thumb is ``tol_fastica == tol_picard ** 2``. .. _eeglab_wiki: https://eeglab.org/tutorials/06_RejectArtifacts/RunICA.html#how-to-deal-with-corrupted-ica-decompositions References ---------- .. footbibliography:: """ # noqa: E501 @verbose def __init__( self, n_components=None, *, noise_cov=None, random_state=None, method="fastica", fit_params=None, max_iter="auto", allow_ref_meg=False, verbose=None, ): _validate_type(method, str, "method") _validate_type(n_components, (float, "int-like", None)) if method != "imported_eeglab": # internal use only _check_option("method", method, _KNOWN_ICA_METHODS) self.noise_cov = noise_cov for kind, val in [("n_components", n_components)]: if isinstance(val, float) and not 0 < val < 1: raise ValueError( "Selecting ICA components by explained " "variance needs values between 0.0 and 1.0 " f"(exclusive), got {kind}={val}" ) if isinstance(val, int_like) and val == 1: raise ValueError( f"Selecting one component with {kind}={val} is not supported" ) self.current_fit = "unfitted" self.n_components = n_components # In newer ICAs this should always be None, but keep it for # backward compat with older versions of MNE that used it self._max_pca_components = None self.n_pca_components = None self.ch_names = None self.random_state = random_state if fit_params is None: fit_params = {} fit_params = deepcopy(fit_params) # avoid side effects if method == "fastica": update = {"algorithm": "parallel", "fun": "logcosh", "fun_args": None} fit_params.update({k: v for k, v in update.items() if k not in fit_params}) elif method == "infomax": # extended=True is default in underlying function, but we want # default False here unless user specified True: fit_params.setdefault("extended", False) _validate_type(max_iter, (str, "int-like"), "max_iter") if isinstance(max_iter, str): _check_option("max_iter", max_iter, ("auto",), "when str") if method == "fastica": max_iter = 1000 elif method in ["infomax", "picard"]: max_iter = 500 fit_params.setdefault("max_iter", max_iter) self.max_iter = max_iter self.fit_params = fit_params self.exclude = [] self.info = None self.method = method self.labels_ = dict() self.allow_ref_meg = allow_ref_meg def _get_infos_for_repr(self): @dataclass class _InfosForRepr: fit_on: Literal["raw data", "epochs"] | None fit_method: Literal["fastica", "infomax", "extended-infomax", "picard"] fit_params: dict[str, str | float] fit_n_iter: int | None fit_n_samples: int | None fit_n_components: int | None fit_n_pca_components: int | None ch_types: list[str] excludes: list[str] if self.current_fit == "unfitted": fit_on = None elif self.current_fit == "raw": fit_on = "raw data" else: fit_on = "epochs" fit_method = self.method fit_params = self.fit_params fit_n_iter = getattr(self, "n_iter_", None) fit_n_samples = getattr(self, "n_samples_", None) fit_n_components = getattr(self, "n_components_", None) fit_n_pca_components = getattr(self, "pca_components_", None) if fit_n_pca_components is not None: fit_n_pca_components = len(self.pca_components_) if self.info is not None: ch_types = [c for c in _DATA_CH_TYPES_SPLIT if c in self] else: ch_types = [] if self.exclude: excludes = [self._ica_names[i] for i in self.exclude] else: excludes = [] infos_for_repr = _InfosForRepr( fit_on=fit_on, fit_method=fit_method, fit_params=fit_params, fit_n_iter=fit_n_iter, fit_n_samples=fit_n_samples, fit_n_components=fit_n_components, fit_n_pca_components=fit_n_pca_components, ch_types=ch_types, excludes=excludes, ) return infos_for_repr def __repr__(self): """ICA fit information.""" infos = self._get_infos_for_repr() s = f'{infos.fit_on or "no"} decomposition, method: {infos.fit_method}' if infos.fit_on is not None: s += ( f" (fit in {infos.fit_n_iter} iterations on " f"{infos.fit_n_samples} samples), " f"{infos.fit_n_components} ICA components " f"({infos.fit_n_pca_components} PCA components available), " f'channel types: {", ".join(infos.ch_types)}, ' f'{len(infos.excludes) or "no"} sources marked for exclusion' ) return f"" @repr_html def _repr_html_(self): infos = self._get_infos_for_repr() t = _get_html_template("repr", "ica.html.jinja") html = t.render( fit_on=infos.fit_on, method=infos.fit_method, fit_params=infos.fit_params, n_iter=infos.fit_n_iter, n_samples=infos.fit_n_samples, n_components=infos.fit_n_components, n_pca_components=infos.fit_n_pca_components, ch_types=infos.ch_types, excludes=infos.excludes, ) return html @verbose def fit( self, inst, picks=None, start=None, stop=None, decim=None, reject=None, flat=None, tstep=2.0, reject_by_annotation=True, verbose=None, ): """Run the ICA decomposition on raw data. Caveat! If supplying a noise covariance keep track of the projections available in the cov, the raw or the epochs object. For example, if you are interested in EOG or ECG artifacts, EOG and ECG projections should be temporally removed before fitting the ICA. Parameters ---------- inst : instance of Raw or Epochs The data to be decomposed. %(picks_good_data_noref)s This selection remains throughout the initialized ICA solution. start, stop : int | float | None First and last sample to include. If float, data will be interpreted as time in seconds. If ``None``, data will be used from the first sample and to the last sample, respectively. .. note:: These parameters only have an effect if ``inst`` is `~mne.io.Raw` data. decim : int | None Increment for selecting only each n-th sampling point. If ``None``, all samples between ``start`` and ``stop`` (inclusive) are used. reject, flat : dict | None Rejection parameters based on peak-to-peak amplitude (PTP) in the continuous data. Signal periods exceeding the thresholds in ``reject`` or less than the thresholds in ``flat`` will be removed before fitting the ICA. .. note:: These parameters only have an effect if ``inst`` is `~mne.io.Raw` data. For `~mne.Epochs`, perform PTP rejection via :meth:`~mne.Epochs.drop_bad`. Valid keys are all channel types present in the data. Values must be integers or floats. If ``None``, no PTP-based rejection will be performed. Example:: reject = dict( grad=4000e-13, # T / m (gradiometers) mag=4e-12, # T (magnetometers) eeg=40e-6, # V (EEG channels) eog=250e-6 # V (EOG channels) ) flat = None # no rejection based on flatness tstep : float Length of data chunks for artifact rejection in seconds. .. note:: This parameter only has an effect if ``inst`` is `~mne.io.Raw` data. %(reject_by_annotation_raw)s .. versionadded:: 0.14.0 %(verbose)s Returns ------- self : instance of ICA Returns the modified instance. """ req_map = dict(fastica="sklearn", picard="picard") for method, mod in req_map.items(): if self.method == method: _require_version(mod, f"use method={repr(method)}") _validate_type(inst, (BaseRaw, BaseEpochs), "inst", "Raw or Epochs") if np.isclose(inst.info["highpass"], 0.0): warn( "The data has not been high-pass filtered. For good ICA " "performance, it should be high-pass filtered (e.g., with a " "1.0 Hz lower bound) before fitting ICA." ) if isinstance(inst, BaseEpochs) and inst.baseline is not None: warn( "The epochs you passed to ICA.fit() were baseline-corrected. " "However, we suggest to fit ICA only on data that has been " "high-pass filtered, but NOT baseline-corrected." ) if not isinstance(inst, BaseRaw): ignored_params = [ param_name for param_name, param_val in zip( ("start", "stop", "reject", "flat"), (start, stop, reject, flat) ) if param_val is not None ] if ignored_params: warn( f"The following parameters passed to ICA.fit() will be " f"ignored, as they only affect raw data (and it appears " f'you passed epochs): {", ".join(ignored_params)}' ) picks = _picks_to_idx( inst.info, picks, allow_empty=False, with_ref_meg=self.allow_ref_meg ) _check_for_unsupported_ica_channels( picks, inst.info, allow_ref_meg=self.allow_ref_meg ) # Actually start fitting t_start = time() if self.current_fit != "unfitted": self._reset() logger.info( "Fitting ICA to data using %i channels " "(please be patient, this may take a while)" % len(picks) ) # n_components could be float 0 < x < 1, but that's okay here if self.n_components is not None and self.n_components > len(picks): raise ValueError( f"ica.n_components ({self.n_components}) cannot " f"be greater than len(picks) ({len(picks)})" ) # filter out all the channels the raw wouldn't have initialized self.info = pick_info(inst.info, picks) if self.info["comps"]: with self.info._unlock(): self.info["comps"] = [] self.ch_names = self.info["ch_names"] if isinstance(inst, BaseRaw): self._fit_raw( inst, picks, start, stop, decim, reject, flat, tstep, reject_by_annotation, verbose, ) else: assert isinstance(inst, BaseEpochs) self._fit_epochs(inst, picks, decim, verbose) # sort ICA components by explained variance var = _ica_explained_variance(self, inst) var_ord = var.argsort()[::-1] _sort_components(self, var_ord, copy=False) t_stop = time() logger.info(f"Fitting ICA took {t_stop - t_start:.1f}s.") return self def _reset(self): """Aux method.""" for key in ( "pre_whitener_", "unmixing_matrix_", "mixing_matrix_", "n_components_", "n_samples_", "pca_components_", "pca_explained_variance_", "pca_mean_", "n_iter_", "drop_inds_", "reject_", ): if hasattr(self, key): delattr(self, key) self.current_fit = "unfitted" def _fit_raw( self, raw, picks, start, stop, decim, reject, flat, tstep, reject_by_annotation, verbose, ): """Aux method.""" start, stop = _check_start_stop(raw, start, stop) reject_by_annotation = "omit" if reject_by_annotation else None # this will be a copy data = raw.get_data(picks, start, stop, reject_by_annotation) # this will be a view if decim is not None: data = data[:, ::decim] # this will make a copy if (reject is not None) or (flat is not None): self.reject_ = reject data, self.drop_inds_ = _reject_data_segments( data, reject, flat, decim, self.info, tstep ) else: self.reject_ = None self.n_samples_ = data.shape[1] self._fit(data, "raw") return self def _fit_epochs(self, epochs, picks, decim, verbose): """Aux method.""" if epochs.events.size == 0: raise RuntimeError( "Tried to fit ICA with epochs, but none were found: epochs.events is " f'"{epochs.events}".' ) # this should be a copy (picks a list of int) data = epochs.get_data(picks=picks) # this will be a view if decim is not None: data = data[:, :, ::decim] self.n_samples_ = data.shape[0] * data.shape[2] # This will make at least one copy (one from hstack, maybe one # more from _pre_whiten) data = np.hstack(data) self._fit(data, "epochs") self.reject_ = deepcopy(epochs.reject) return self def _compute_pre_whitener(self, data): """Aux function.""" data = self._do_proj(data, log_suffix="(pre-whitener computation)") if self.noise_cov is None: # use standardization as whitener # Scale (z-score) the data by channel type info = self.info pre_whitener = np.empty([len(data), 1]) for _, picks_ in _picks_by_type(info, ref_meg=False, exclude=[]): pre_whitener[picks_] = np.std(data[picks_]) if _contains_ch_type(info, "ref_meg"): picks_ = pick_types(info, ref_meg=True, exclude=[]) pre_whitener[picks_] = np.std(data[picks_]) if _contains_ch_type(info, "eog"): picks_ = pick_types(info, eog=True, exclude=[]) pre_whitener[picks_] = np.std(data[picks_]) else: pre_whitener, _ = compute_whitener( self.noise_cov, self.info, picks=self.info.ch_names ) assert data.shape[0] == pre_whitener.shape[1] self.pre_whitener_ = pre_whitener def _do_proj(self, data, log_suffix=""): if self.info is not None and self.info["projs"]: proj, nproj, _ = make_projector( [p for p in self.info["projs"] if p["active"]], self.info["ch_names"], include_active=True, ) if nproj: logger.info( f" Applying projection operator with {nproj} " f"vector{_pl(nproj)}" f'{" " if log_suffix else ""}{log_suffix}' ) if self.noise_cov is None: # otherwise it's in pre_whitener_ data = proj @ data return data def _pre_whiten(self, data): data = self._do_proj(data, log_suffix="(pre-whitener application)") if self.noise_cov is None: data /= self.pre_whitener_ else: data = self.pre_whitener_ @ data return data def _fit(self, data, fit_type): """Aux function.""" random_state = check_random_state(self.random_state) n_channels, n_samples = data.shape self._compute_pre_whitener(data) data = self._pre_whiten(data) pca = _PCA(n_components=self._max_pca_components, whiten=True) data = pca.fit_transform(data.T) use_ev = pca.explained_variance_ratio_ n_pca = self.n_pca_components if isinstance(n_pca, float): n_pca = int(_exp_var_ncomp(use_ev, n_pca)[0]) elif n_pca is None: n_pca = len(use_ev) assert isinstance(n_pca, (int, np.int_)) # If user passed a float, select the PCA components explaining the # given cumulative variance. This information will later be used to # only submit the corresponding parts of the data to ICA. if self.n_components is None: # None case: check if n_pca_components or 0.999999 yields smaller msg = "Selecting by non-zero PCA components" self.n_components_ = min(n_pca, _exp_var_ncomp(use_ev, 0.999999)[0]) elif isinstance(self.n_components, float): self.n_components_, ev = _exp_var_ncomp(use_ev, self.n_components) if self.n_components_ == 1: raise RuntimeError( "One PCA component captures most of the " f"explained variance ({100 * ev}%), your threshold " "results in 1 component. You should select " "a higher value." ) msg = "Selecting by explained variance" else: msg = "Selecting by number" self.n_components_ = _ensure_int(self.n_components) # check to make sure something okay happened if self.n_components_ > n_pca: ev = np.cumsum(use_ev) ev /= ev[-1] evs = 100 * ev[[self.n_components_ - 1, n_pca - 1]] raise RuntimeError( f"n_components={self.n_components} requires " f"{self.n_components_} PCA values (EV={evs[0]:0.1f}%) but " f"n_pca_components ({self.n_pca_components}) results in " f"only {n_pca} components (EV={evs[1]:0.1f}%)" ) logger.info(f"{msg}: {self.n_components_} components") # the things to store for PCA self.pca_mean_ = pca.mean_ self.pca_components_ = pca.components_ self.pca_explained_variance_ = pca.explained_variance_ del pca # update number of components self._update_ica_names() if self.n_pca_components is not None and self.n_pca_components > len( self.pca_components_ ): raise ValueError( f"n_pca_components ({self.n_pca_components}) is greater than " f"the number of PCA components ({len(self.pca_components_)})" ) # take care of ICA sel = slice(0, self.n_components_) if self.method == "fastica": from sklearn.decomposition import FastICA ica = FastICA(whiten=False, random_state=random_state, **self.fit_params) ica.fit(data[:, sel]) self.unmixing_matrix_ = ica.components_ self.n_iter_ = ica.n_iter_ elif self.method in ("infomax", "extended-infomax"): unmixing_matrix, n_iter = infomax( data[:, sel], random_state=random_state, return_n_iter=True, **self.fit_params, ) self.unmixing_matrix_ = unmixing_matrix self.n_iter_ = n_iter del unmixing_matrix, n_iter elif self.method == "picard": from picard import picard _, W, _, n_iter = picard( data[:, sel].T, whiten=False, return_n_iter=True, random_state=random_state, **self.fit_params, ) self.unmixing_matrix_ = W self.n_iter_ = n_iter + 1 # picard() starts counting at 0 del _, n_iter assert self.unmixing_matrix_.shape == (self.n_components_,) * 2 norms = self.pca_explained_variance_ stable = norms / norms[0] > 1e-6 # to be stable during pinv norms = norms[: self.n_components_] if not stable[self.n_components_ - 1]: max_int = np.where(stable)[0][-1] + 1 warn( f"Using n_components={self.n_components} (resulting in " f"n_components_={self.n_components_}) may lead to an " f"unstable mixing matrix estimation because the ratio " f"between the largest ({norms[0]:0.2g}) and smallest " f"({norms[-1]:0.2g}) variances is too large (> 1e6); " f"consider setting n_components=0.999999 or an " f"integer <= {max_int}" ) norms = np.sqrt(norms) norms[norms == 0] = 1.0 self.unmixing_matrix_ /= norms # whitening self._update_mixing_matrix() self.current_fit = fit_type def _update_mixing_matrix(self): self.mixing_matrix_ = pinv(self.unmixing_matrix_) def _update_ica_names(self): """Update ICA names when n_components_ is set.""" self._ica_names = ["ICA%03d" % ii for ii in range(self.n_components_)] def _transform(self, data): """Compute sources from data (operates inplace).""" data = self._pre_whiten(data) if self.pca_mean_ is not None: data -= self.pca_mean_[:, None] # Apply unmixing pca_data = np.dot( self.unmixing_matrix_, self.pca_components_[: self.n_components_] ) # Apply PCA sources = np.dot(pca_data, data) return sources def _transform_raw(self, raw, start, stop, reject_by_annotation=False): """Transform raw data.""" if not hasattr(self, "mixing_matrix_"): raise RuntimeError("No fit available. Please fit ICA.") start, stop = _check_start_stop(raw, start, stop) picks = self._get_picks(raw) reject = "omit" if reject_by_annotation else None data = raw.get_data(picks, start, stop, reject) return self._transform(data) def _transform_epochs(self, epochs, concatenate): """Aux method.""" if not hasattr(self, "mixing_matrix_"): raise RuntimeError("No fit available. Please fit ICA.") picks = self._get_picks(epochs) data = np.hstack(epochs.get_data(picks=picks)) sources = self._transform(data) if not concatenate: # Put the data back in 3D sources = np.array(np.split(sources, len(epochs.events), 1)) return sources def _transform_evoked(self, evoked): """Aux method.""" if not hasattr(self, "mixing_matrix_"): raise RuntimeError("No fit available. Please fit ICA.") picks = self._get_picks(evoked) return self._transform(evoked.data[picks]) def _get_picks(self, inst): """Pick logic for _transform method.""" picks = _picks_to_idx(inst.info, self.ch_names, exclude=[], allow_empty=True) if len(picks) != len(self.ch_names): if isinstance(inst, BaseRaw): kind, do = "Raw", "doesn't" elif isinstance(inst, BaseEpochs): kind, do = "Epochs", "don't" elif isinstance(inst, Evoked): kind, do = "Evoked", "doesn't" else: raise ValueError("Data input must be of Raw, Epochs or Evoked type") raise RuntimeError( "%s %s match fitted data: %i channels " "fitted but %i channels supplied. \nPlease " "provide %s compatible with ica.ch_names" % (kind, do, len(self.ch_names), len(picks), kind) ) return picks def get_components(self): """Get ICA topomap for components as numpy arrays. Returns ------- components : array, shape (n_channels, n_components) The ICA components (maps). """ return np.dot( self.mixing_matrix_[:, : self.n_components_].T, self.pca_components_[: self.n_components_], ).T def get_explained_variance_ratio(self, inst, *, components=None, ch_type=None): """Get the proportion of data variance explained by ICA components. Parameters ---------- inst : mne.io.BaseRaw | mne.BaseEpochs | mne.Evoked The uncleaned data. components : array-like of int | int | None The component(s) for which to do the calculation. If more than one component is specified, explained variance will be calculated jointly across all supplied components. If ``None`` (default), uses all available components. ch_type : 'mag' | 'grad' | 'planar1' | 'planar2' | 'eeg' | array-like of str | None The channel type(s) to include in the calculation. If ``None``, all available channel types will be used. Returns ------- dict (str, float) The fraction of variance in ``inst`` that can be explained by the ICA components, calculated separately for each channel type. Dictionary keys are the channel types, and corresponding explained variance ratios are the values. Notes ----- A value similar to EEGLAB's ``pvaf`` (percent variance accounted for) will be calculated for the specified component(s). Since ICA components cannot be assumed to be aligned orthogonally, the sum of the proportion of variance explained by all components may not be equal to 1. In certain situations, the proportion of variance explained by a component may even be negative. .. versionadded:: 1.2 """ # noqa: E501 if self.current_fit == "unfitted": raise ValueError("ICA must be fitted first.") _validate_type(item=inst, types=(BaseRaw, BaseEpochs, Evoked), item_name="inst") _validate_type( item=components, types=(None, "int-like", Sequence, np.ndarray), item_name="components", type_name="int, array-like of int, or None", ) if isinstance(components, (Sequence, np.ndarray)): for item in components: _validate_type( item=item, types="int-like", item_name='Elements of "components"' ) _validate_type( item=ch_type, types=(Sequence, np.ndarray, str, None), item_name="ch_type", type_name="str, array-like of str, or None", ) if isinstance(ch_type, str): ch_types = [ch_type] elif ch_type is None: ch_types = inst.get_channel_types(unique=True, only_data_chs=True) else: assert isinstance(ch_type, (Sequence, np.ndarray)) ch_types = ch_type assert len(ch_types) >= 1 allowed_ch_types = ("mag", "grad", "planar1", "planar2", "eeg") for ch_type in ch_types: if ch_type not in allowed_ch_types: raise ValueError( f"You requested operation on the channel type " f'"{ch_type}", but only the following channel types are ' f'supported: {", ".join(allowed_ch_types)}' ) del ch_type # Input data validation ends here if components is None: components = range(self.n_components_) explained_var_ratios = [ self._get_explained_variance_ratio_one_ch_type( inst=inst, components=components, ch_type=ch_type ) for ch_type in ch_types ] result = dict(zip(ch_types, explained_var_ratios)) return result def _get_explained_variance_ratio_one_ch_type(self, *, inst, components, ch_type): # The algorithm implemented below should be equivalent to # https://sccn.ucsd.edu/pipermail/eeglablist/2014/009134.html # # Reconstruct ("back-project") the data using only the specified ICA # components. Don't make use of potential "spare" PCA components in # this process – we're only interested in the contribution of the ICA # components! kwargs = dict( inst=inst.copy(), include=[components], exclude=[], n_pca_components=0, verbose=False, ) if isinstance(inst, (BaseEpochs, Evoked)) and inst.baseline is not None: # Don't warn if data was baseline-corrected. with warnings.catch_warnings(): warnings.filterwarnings( action="ignore", message="The data.*was baseline-corrected", category=RuntimeWarning, ) inst_recon = self.apply(**kwargs) else: inst_recon = self.apply(**kwargs) data_recon = inst_recon.get_data(picks=ch_type) data_orig = inst.get_data(picks=ch_type) data_diff = data_orig - data_recon # To estimate the data variance, we first compute the variance across # channels at each time point, and then we average these variances. mean_var_diff = data_diff.var(axis=0).mean() mean_var_orig = data_orig.var(axis=0).mean() var_explained_ratio = 1 - mean_var_diff / mean_var_orig return var_explained_ratio def get_sources(self, inst, add_channels=None, start=None, stop=None): """Estimate sources given the unmixing matrix. This method will return the sources in the container format passed. Typical usecases: 1. pass Raw object to use `raw.plot ` for ICA sources 2. pass Epochs object to compute trial-based statistics in ICA space 3. pass Evoked object to investigate time-locking in ICA space Parameters ---------- inst : instance of Raw, Epochs or Evoked Object to compute sources from and to represent sources in. add_channels : None | list of str Additional channels to be added. Useful to e.g. compare sources with some reference. Defaults to None. start : int | float | None First sample to include. If float, data will be interpreted as time in seconds. If None, the entire data will be used. stop : int | float | None Last sample to not include. If float, data will be interpreted as time in seconds. If None, the entire data will be used. Returns ------- sources : instance of Raw, Epochs or Evoked The ICA sources time series. """ if isinstance(inst, BaseRaw): _check_compensation_grade( self.info, inst.info, "ICA", "Raw", ch_names=self.ch_names ) sources = self._sources_as_raw(inst, add_channels, start, stop) elif isinstance(inst, BaseEpochs): _check_compensation_grade( self.info, inst.info, "ICA", "Epochs", ch_names=self.ch_names ) sources = self._sources_as_epochs(inst, add_channels, False) elif isinstance(inst, Evoked): _check_compensation_grade( self.info, inst.info, "ICA", "Evoked", ch_names=self.ch_names ) sources = self._sources_as_evoked(inst, add_channels) else: raise ValueError("Data input must be of Raw, Epochs or Evoked type") return sources def _sources_as_raw(self, raw, add_channels, start, stop): """Aux method.""" # merge copied instance and picked data with sources start, stop = _check_start_stop(raw, start, stop) data_ = self._transform_raw(raw, start=start, stop=stop) assert data_.shape[1] == stop - start preloaded = raw.preload if raw.preload: # get data and temporarily delete data = raw._data raw.preload = False del raw._data # copy and crop here so that things like annotations are adjusted try: out = raw.copy().crop( start / raw.info["sfreq"], (stop - 1) / raw.info["sfreq"] ) finally: # put the data back (always) if preloaded: raw.preload = True raw._data = data # populate copied raw. if add_channels is not None and len(add_channels): picks = pick_channels(raw.ch_names, add_channels) data_ = np.concatenate([data_, raw.get_data(picks, start=start, stop=stop)]) out._data = data_ out._first_samps = [out.first_samp] out._last_samps = [out.last_samp] out._filenames = [None] out.preload = True out._projector = None self._export_info(out.info, raw, add_channels) return out def _sources_as_epochs(self, epochs, add_channels, concatenate): """Aux method.""" out = epochs.copy() sources = self._transform_epochs(epochs, concatenate) if add_channels is not None: picks = [epochs.ch_names.index(k) for k in add_channels] else: picks = [] out._data = ( np.concatenate([sources, epochs.get_data()[:, picks]], axis=1) if len(picks) > 0 else sources ) self._export_info(out.info, epochs, add_channels) out.preload = True out._raw = None out._projector = None return out def _sources_as_evoked(self, evoked, add_channels): """Aux method.""" if add_channels is not None: picks = [evoked.ch_names.index(k) for k in add_channels] else: picks = [] sources = self._transform_evoked(evoked) if len(picks) > 1: data = np.r_[sources, evoked.data[picks]] else: data = sources out = evoked.copy() out.data = data self._export_info(out.info, evoked, add_channels) return out def _export_info(self, info, container, add_channels): """Aux method.""" # set channel names and info ch_names = [] ch_info = [] for ii, name in enumerate(self._ica_names): ch_names.append(name) ch_info.append( dict( ch_name=name, cal=1, logno=ii + 1, coil_type=FIFF.FIFFV_COIL_NONE, kind=FIFF.FIFFV_MISC_CH, coord_frame=FIFF.FIFFV_COORD_UNKNOWN, unit=FIFF.FIFF_UNIT_NONE, loc=np.zeros(12, dtype="f4"), range=1.0, scanno=ii + 1, unit_mul=0, ) ) if add_channels is not None: # re-append additionally picked ch_names ch_names += add_channels # re-append additionally picked ch_info ch_info += [ k for k in container.info["chs"] if k["ch_name"] in add_channels ] with info._unlock(update_redundant=True, check_after=True): info["chs"] = ch_info info["projs"] = [] # make sure projections are removed. info["bads"] = [ch_names[k] for k in self.exclude] @verbose def score_sources( self, inst, target=None, score_func="pearsonr", start=None, stop=None, l_freq=None, h_freq=None, reject_by_annotation=True, verbose=None, ): """Assign score to components based on statistic or metric. Parameters ---------- inst : instance of Raw, Epochs or Evoked The object to reconstruct the sources from. target : array-like | str | None Signal to which the sources shall be compared. It has to be of the same shape as the sources. If str, a routine will try to find a matching channel name. If None, a score function expecting only one input-array argument must be used, for instance, scipy.stats.skew (default). score_func : callable | str Callable taking as arguments either two input arrays (e.g. Pearson correlation) or one input array (e. g. skewness) and returns a float. For convenience the most common score_funcs are available via string labels: Currently, all distance metrics from scipy.spatial and All functions from scipy.stats taking compatible input arguments are supported. These function have been modified to support iteration over the rows of a 2D array. start : int | float | None First sample to include. If float, data will be interpreted as time in seconds. If None, data will be used from the first sample. stop : int | float | None Last sample to not include. If float, data will be interpreted as time in seconds. If None, data will be used to the last sample. l_freq : float Low pass frequency. h_freq : float High pass frequency. %(reject_by_annotation_all)s .. versionadded:: 0.14.0 %(verbose)s Returns ------- scores : ndarray Scores for each source as returned from score_func. """ if isinstance(inst, BaseRaw): _check_compensation_grade( self.info, inst.info, "ICA", "Raw", ch_names=self.ch_names ) sources = self._transform_raw(inst, start, stop, reject_by_annotation) elif isinstance(inst, BaseEpochs): _check_compensation_grade( self.info, inst.info, "ICA", "Epochs", ch_names=self.ch_names ) sources = self._transform_epochs(inst, concatenate=True) elif isinstance(inst, Evoked): _check_compensation_grade( self.info, inst.info, "ICA", "Evoked", ch_names=self.ch_names ) sources = self._transform_evoked(inst) else: raise ValueError("Data input must be of Raw, Epochs or Evoked type") if target is not None: # we can have univariate metrics without target target = self._check_target(target, inst, start, stop, reject_by_annotation) if sources.shape[-1] != target.shape[-1]: raise ValueError( "Sources and target do not have the same number of time slices." ) # auto target selection if isinstance(inst, BaseRaw): # We pass inst, not self, because the sfreq of the data we # use for scoring components can be different: sources, target = _band_pass_filter( inst, sources, target, l_freq, h_freq ) scores = _find_sources(sources, target, score_func) return scores def _check_target(self, target, inst, start, stop, reject_by_annotation=False): """Aux Method.""" if isinstance(inst, BaseRaw): reject_by_annotation = "omit" if reject_by_annotation else None start, stop = _check_start_stop(inst, start, stop) if hasattr(target, "ndim"): if target.ndim < 2: target = target.reshape(1, target.shape[-1]) if isinstance(target, str): pick = _get_target_ch(inst, target) target = inst.get_data(pick, start, stop, reject_by_annotation) elif isinstance(inst, BaseEpochs): if isinstance(target, str): pick = _get_target_ch(inst, target) target = inst.get_data(picks=pick) if hasattr(target, "ndim"): if target.ndim == 3 and min(target.shape) == 1: target = target.ravel() elif isinstance(inst, Evoked): if isinstance(target, str): pick = _get_target_ch(inst, target) target = inst.data[pick] return target def _find_bads_ch( self, inst, chs, threshold=3.0, start=None, stop=None, l_freq=None, h_freq=None, reject_by_annotation=True, prefix="chs", measure="zscore", ): """Compute ExG/ref components. See find_bads_ecg, find_bads_eog, and find_bads_ref for details. """ scores, idx = [], [] # some magic we need inevitably ... # get targets before equalizing targets = [ self._check_target(ch, inst, start, stop, reject_by_annotation) for ch in chs ] # assign names, if targets are arrays instead of strings target_names = [] for ch in chs: if not isinstance(ch, str): if prefix == "ecg": target_names.append("ECG-MAG") else: target_names.append(prefix) else: target_names.append(ch) for ii, (ch, target) in enumerate(zip(target_names, targets)): scores += [ self.score_sources( inst, target=target, score_func="pearsonr", start=start, stop=stop, l_freq=l_freq, h_freq=h_freq, reject_by_annotation=reject_by_annotation, ) ] # pick last scores if measure == "zscore": this_idx = _find_outliers(scores[-1], threshold=threshold) elif measure == "correlation": this_idx = np.where(abs(scores[-1]) > threshold)[0] else: raise ValueError(f"Unknown measure {measure}") idx += [this_idx] self.labels_["%s/%i/" % (prefix, ii) + ch] = list(this_idx) # remove duplicates but keep order by score, even across multiple # ref channels scores_ = np.concatenate([scores[ii][inds] for ii, inds in enumerate(idx)]) idx_ = np.concatenate(idx)[np.abs(scores_).argsort()[::-1]] idx_unique = list(np.unique(idx_)) idx = [] for i in idx_: if i in idx_unique: idx.append(i) idx_unique.remove(i) if len(scores) == 1: scores = scores[0] labels = list(idx) return labels, scores def _get_ctps_threshold(self, pk_threshold=20): """Automatically decide the threshold of Kuiper index for CTPS method. This function finds the threshold of Kuiper index based on the threshold of pk. Kuiper statistic that minimizes the difference between pk and the pk threshold (defaults to 20 :footcite:`DammersEtAl2008`) is returned. It is assumed that the data are appropriately filtered and bad data are rejected at least based on peak-to-peak amplitude when/before running the ICA decomposition on data. References ---------- .. footbibliography:: """ N = self.info["sfreq"] Vs = np.arange(1, 100) / 100 C = math.sqrt(N) + 0.155 + 0.24 / math.sqrt(N) # in formula (13), when k gets large, only k=1 matters for the # summation. k*V*C thus becomes V*C Pks = 2 * (4 * (Vs * C) ** 2 - 1) * (np.exp(-2 * (Vs * C) ** 2)) # NOTE: the threshold of pk is transformed to Pk for comparison # pk = -log10(Pk) return Vs[np.argmin(np.abs(Pks - 10 ** (-pk_threshold)))] @verbose def find_bads_ecg( self, inst, ch_name=None, threshold="auto", start=None, stop=None, l_freq=8, h_freq=16, method="ctps", reject_by_annotation=True, measure="zscore", verbose=None, ): """Detect ECG related components. Cross-trial phase statistics :footcite:`DammersEtAl2008` or Pearson correlation can be used for detection. .. note:: If no ECG channel is available, routine attempts to create an artificial ECG based on cross-channel averaging. Parameters ---------- inst : instance of Raw, Epochs or Evoked Object to compute sources from. ch_name : str The name of the channel to use for ECG peak detection. The argument is mandatory if the dataset contains no ECG channels. threshold : float | 'auto' Value above which a feature is classified as outlier. See Notes. .. versionchanged:: 0.21 start : int | float | None First sample to include. If float, data will be interpreted as time in seconds. If None, data will be used from the first sample. When working with Epochs or Evoked objects, must be float or None. stop : int | float | None Last sample to not include. If float, data will be interpreted as time in seconds. If None, data will be used to the last sample. When working with Epochs or Evoked objects, must be float or None. l_freq : float Low pass frequency. h_freq : float High pass frequency. method : 'ctps' | 'correlation' The method used for detection. If ``'ctps'``, cross-trial phase statistics :footcite:`DammersEtAl2008` are used to detect ECG-related components. See Notes. %(reject_by_annotation_all)s .. versionadded:: 0.14.0 %(measure)s %(verbose)s Returns ------- ecg_idx : list of int The indices of ECG-related components. scores : np.ndarray of float, shape (``n_components_``) If method is 'ctps', the normalized Kuiper index scores. If method is 'correlation', the correlation scores. See Also -------- find_bads_eog, find_bads_ref, find_bads_muscle Notes ----- The ``threshold``, ``method``, and ``measure`` parameters interact in the following ways: - If ``method='ctps'``, ``threshold`` refers to the significance value of a Kuiper statistic, and ``threshold='auto'`` will compute the threshold automatically based on the sampling frequency. - If ``method='correlation'`` and ``measure='correlation'``, ``threshold`` refers to the Pearson correlation value, and ``threshold='auto'`` sets the threshold to 0.9. - If ``method='correlation'`` and ``measure='zscore'``, ``threshold`` refers to the z-score value (i.e., standard deviations) used in the iterative z-scoring method, and ``threshold='auto'`` sets the threshold to 3.0. References ---------- .. footbibliography:: """ _validate_type(threshold, (str, "numeric"), "threshold") if isinstance(threshold, str): _check_option("threshold", threshold, ("auto",), extra="when str") _validate_type(method, str, "method") _check_option("method", method, ("ctps", "correlation")) _validate_type(measure, str, "measure") _check_option("measure", measure, ("zscore", "correlation")) idx_ecg = _get_ecg_channel_index(ch_name, inst) if idx_ecg is None: ecg, times = _make_ecg( inst, start, stop, reject_by_annotation=reject_by_annotation ) else: ecg = inst.ch_names[idx_ecg] if method == "ctps": if threshold == "auto": threshold = self._get_ctps_threshold() logger.info(f"Using threshold: {threshold:.2f} for CTPS ECG detection") if isinstance(inst, BaseRaw): sources = self.get_sources( create_ecg_epochs( inst, ch_name, l_freq=l_freq, h_freq=h_freq, keep_ecg=False, reject_by_annotation=reject_by_annotation, ) ).get_data(copy=False) if sources.shape[0] == 0: warn( "No ECG activity detected. Consider changing " "the input parameters." ) elif isinstance(inst, BaseEpochs): sources = self.get_sources(inst).get_data(copy=False) else: raise ValueError("With `ctps` only Raw and Epochs input is supported") _, p_vals, _ = ctps(sources) scores = p_vals.max(-1) ecg_idx = np.where(scores >= threshold)[0] # sort indices by scores ecg_idx = ecg_idx[np.abs(scores[ecg_idx]).argsort()[::-1]] self.labels_["ecg"] = list(ecg_idx) if ch_name is None: ch_name = "ECG-MAG" self.labels_[f"ecg/{ch_name}"] = list(ecg_idx) elif method == "correlation": if threshold == "auto" and measure == "zscore": threshold = 3.0 elif threshold == "auto" and measure == "correlation": threshold = 0.9 self.labels_["ecg"], scores = self._find_bads_ch( inst, [ecg], threshold=threshold, start=start, stop=stop, l_freq=l_freq, h_freq=h_freq, prefix="ecg", reject_by_annotation=reject_by_annotation, measure=measure, ) return self.labels_["ecg"], scores @verbose def find_bads_ref( self, inst, ch_name=None, threshold=3.0, start=None, stop=None, l_freq=None, h_freq=None, reject_by_annotation=True, method="together", measure="zscore", verbose=None, ): """Detect MEG reference related components using correlation. Parameters ---------- inst : instance of Raw, Epochs or Evoked Object to compute sources from. Should contain at least one channel i.e. component derived from MEG reference channels. ch_name : list of str Which MEG reference components to use. If None, then all channels that begin with REF_ICA. threshold : float | str Value above which a feature is classified as outlier. - If ``measure`` is ``'zscore'``, defines the threshold on the z-score used in the iterative z-scoring method. - If ``measure`` is ``'correlation'``, defines the absolute threshold on the correlation between 0 and 1. - If ``'auto'``, defaults to 3.0 if ``measure`` is ``'zscore'`` and 0.9 if ``measure`` is ``'correlation'``. .. warning:: If ``method`` is ``'together'``, the iterative z-score method is always used. start : int | float | None First sample to include. If float, data will be interpreted as time in seconds. If None, data will be used from the first sample. stop : int | float | None Last sample to not include. If float, data will be interpreted as time in seconds. If None, data will be used to the last sample. l_freq : float Low pass frequency. h_freq : float High pass frequency. %(reject_by_annotation_all)s method : 'together' | 'separate' Method to use to identify reference channel related components. Defaults to ``'together'``. See notes. .. versionadded:: 0.21 %(measure)s %(verbose)s Returns ------- ref_idx : list of int The indices of MEG reference related components, sorted by score. scores : np.ndarray of float, shape (``n_components_``) | list of array The correlation scores. See Also -------- find_bads_ecg, find_bads_eog, find_bads_muscle Notes ----- ICA decomposition on MEG reference channels is used to assess external magnetic noise and remove it from the MEG. Two methods are supported: With the ``'together'`` method, only one ICA fit is used, which encompasses both MEG and reference channels together. Components which have particularly strong weights on the reference channels may be thresholded and marked for removal. With ``'separate'`` selected components from a separate ICA decomposition on the reference channels are used as a ground truth for identifying bad components in an ICA fit done on MEG channels only. The logic here is similar to an EOG/ECG, with reference components replacing the EOG/ECG channels. Recommended procedure is to perform ICA separately on reference channels, extract them using :meth:`~mne.preprocessing.ICA.get_sources`, and then append them to the inst using :meth:`~mne.io.Raw.add_channels`, preferably with the prefix ``REF_ICA`` so that they can be automatically detected. With ``'together'``, thresholding is based on adaptative z-scoring. With ``'separate'``: - If ``measure`` is ``'zscore'``, thresholding is based on adaptative z-scoring. - If ``measure`` is ``'correlation'``, threshold defines the absolute threshold on the correlation between 0 and 1. Validation and further documentation for this technique can be found in :footcite:`HannaEtAl2020`. .. versionadded:: 0.18 References ---------- .. footbibliography:: """ _validate_type(threshold, (str, "numeric"), "threshold") if isinstance(threshold, str): _check_option("threshold", threshold, ("auto",), extra="when str") _validate_type(method, str, "method") _check_option("method", method, ("together", "separate")) _validate_type(measure, str, "measure") _check_option("measure", measure, ("zscore", "correlation")) if method == "separate": if threshold == "auto" and measure == "zscore": threshold = 3.0 elif threshold == "auto" and measure == "correlation": threshold = 0.9 if not ch_name: inds = pick_channels_regexp(inst.ch_names, "REF_ICA*") else: inds = pick_channels(inst.ch_names, ch_name) # regexp returns list, pick_channels returns numpy inds = list(inds) if not inds: raise ValueError("No valid channels available.") ref_chs = [inst.ch_names[k] for k in inds] self.labels_["ref_meg"], scores = self._find_bads_ch( inst, ref_chs, threshold=threshold, start=start, stop=stop, l_freq=l_freq, h_freq=h_freq, prefix="ref_meg", reject_by_annotation=reject_by_annotation, measure=measure, ) elif method == "together": if threshold == "auto": threshold = 3.0 if measure != "zscore": logger.info( "With method 'together', only 'zscore' measure is" f"supported. Using 'zscore' instead of '{measure}'." ) meg_picks = pick_types(self.info, meg=True, ref_meg=False) ref_picks = pick_types(self.info, meg=False, ref_meg=True) if not any(meg_picks) or not any(ref_picks): raise ValueError( "ICA solution must contain both reference and MEG channels." ) weights = self.get_components() # take norm of component weights on reference channels for each # component, divide them by the norm on the standard channels, # log transform to approximate normal distribution normrats = np.linalg.norm(weights[ref_picks], axis=0) / np.linalg.norm( weights[meg_picks], axis=0 ) scores = np.log(normrats) self.labels_["ref_meg"] = list( _find_outliers(scores, threshold=threshold, tail=1) ) return self.labels_["ref_meg"], scores @verbose def find_bads_muscle( self, inst, threshold=0.5, start=None, stop=None, l_freq=7, h_freq=45, sphere=None, verbose=None, ): """Detect muscle related components. Detection is based on :footcite:`DharmapraniEtAl2016` which uses data from a subject who has been temporarily paralyzed :footcite:`WhithamEtAl2007`. The criteria are threefold: 1) Positive log-log spectral slope from 7 to 45 Hz 2) Peripheral component power (farthest away from the vertex) 3) A single focal point measured by low spatial smoothness The threshold is relative to the slope, focal point and smoothness of a typical muscle-related ICA component. Note the high frequency of the power spectral density slope was 75 Hz in the reference but has been modified to 45 Hz as a default based on the criteria being more accurate in practice. Parameters ---------- inst : instance of Raw, Epochs or Evoked Object to compute sources from. threshold : float | str Value above which a component should be marked as muscle-related, relative to a typical muscle component. start : int | float | None First sample to include. If float, data will be interpreted as time in seconds. If None, data will be used from the first sample. stop : int | float | None Last sample to not include. If float, data will be interpreted as time in seconds. If None, data will be used to the last sample. l_freq : float Low frequency for muscle-related power. h_freq : float High frequency for msucle related power. %(sphere_topomap_auto)s %(verbose)s Returns ------- muscle_idx : list of int The indices of EOG related components, sorted by score. scores : np.ndarray of float, shape (``n_components_``) | list of array The correlation scores. See Also -------- find_bads_ecg, find_bads_eog, find_bads_ref Notes ----- .. versionadded:: 1.1 """ _validate_type(threshold, "numeric", "threshold") sources = self.get_sources(inst, start=start, stop=stop) components = self.get_components() # compute metric #1: slope of the log-log psd spectrum = sources.compute_psd(fmin=l_freq, fmax=h_freq, picks="misc") psds, freqs = spectrum.get_data(return_freqs=True) if psds.ndim > 2: psds = psds.mean(axis=0) slopes = np.polyfit(np.log10(freqs), np.log10(psds).T, 1)[0] # compute metric #2: distance from the vertex of focus components_norm = abs(components) / np.max(abs(components), axis=0) # we need to retrieve the position from the channels that were used to # fit the ICA. N.B: picks in _find_topomap_coords includes bad channels # even if they are not provided explicitly. pos = _find_topomap_coords( inst.info, picks=self.ch_names, sphere=sphere, ignore_overlap=True ) assert pos.shape[0] == components.shape[0] # pos for each sensor pos -= pos.mean(axis=0) # center dists = np.linalg.norm(pos, axis=1) dists /= dists.max() focus_dists = np.dot(dists, components_norm) # compute metric #3: smoothness smoothnesses = np.zeros((components.shape[1],)) dists = distance.squareform(distance.pdist(pos)) dists = 1 - (dists / dists.max()) # invert for idx, comp in enumerate(components.T): comp_dists = distance.squareform(distance.pdist(comp[:, np.newaxis])) comp_dists /= comp_dists.max() smoothnesses[idx] = np.multiply(dists, comp_dists).sum() # typical muscle slope is ~0.15, non-muscle components negative # so logistic with shift -0.5 and slope 0.25 so -0.5 -> 0.5 and 0->1 slope_score = expit((slopes + 0.5) / 0.25) # focus distance is ~65% of max electrode distance with 10% slope # (assumes typical head size) focus_score = expit((focus_dists - 0.65) / 0.1) # smoothnessness is around 150 for muscle and 450 otherwise # so use reversed logistic centered at 300 with 100 slope smoothness_score = 1 - expit((smoothnesses - 300) / 100) # multiply so that all three components must be present scores = slope_score * focus_score * smoothness_score # scale the threshold by the use of three metrics self.labels_["muscle"] = [ idx for idx, score in enumerate(scores) if score > threshold**3 ] return self.labels_["muscle"], scores @verbose def find_bads_eog( self, inst, ch_name=None, threshold=3.0, start=None, stop=None, l_freq=1, h_freq=10, reject_by_annotation=True, measure="zscore", verbose=None, ): """Detect EOG related components using correlation. Detection is based on Pearson correlation between the filtered data and the filtered EOG channel. Thresholding is based on adaptive z-scoring. The above threshold components will be masked and the z-score will be recomputed until no supra-threshold component remains. Parameters ---------- inst : instance of Raw, Epochs or Evoked Object to compute sources from. ch_name : str The name of the channel to use for EOG peak detection. The argument is mandatory if the dataset contains no EOG channels. threshold : float | str Value above which a feature is classified as outlier. - If ``measure`` is ``'zscore'``, defines the threshold on the z-score used in the iterative z-scoring method. - If ``measure`` is ``'correlation'``, defines the absolute threshold on the correlation between 0 and 1. - If ``'auto'``, defaults to 3.0 if ``measure`` is ``'zscore'`` and 0.9 if ``measure`` is ``'correlation'``. start : int | float | None First sample to include. If float, data will be interpreted as time in seconds. If None, data will be used from the first sample. stop : int | float | None Last sample to not include. If float, data will be interpreted as time in seconds. If None, data will be used to the last sample. l_freq : float Low pass frequency. h_freq : float High pass frequency. %(reject_by_annotation_all)s .. versionadded:: 0.14.0 %(measure)s %(verbose)s Returns ------- eog_idx : list of int The indices of EOG related components, sorted by score. scores : np.ndarray of float, shape (``n_components_``) | list of array The correlation scores. See Also -------- find_bads_ecg, find_bads_ref """ _validate_type(threshold, (str, "numeric"), "threshold") if isinstance(threshold, str): _check_option("threshold", threshold, ("auto",), extra="when str") _validate_type(measure, str, "measure") _check_option("measure", measure, ("zscore", "correlation")) eog_inds = _get_eog_channel_index(ch_name, inst) eog_chs = [inst.ch_names[k] for k in eog_inds] if threshold == "auto" and measure == "zscore": threshold = 3.0 elif threshold == "auto" and measure == "correlation": threshold = 0.9 self.labels_["eog"], scores = self._find_bads_ch( inst, eog_chs, threshold=threshold, start=start, stop=stop, l_freq=l_freq, h_freq=h_freq, prefix="eog", reject_by_annotation=reject_by_annotation, measure=measure, ) return self.labels_["eog"], scores @verbose def apply( self, inst, include=None, exclude=None, n_pca_components=None, start=None, stop=None, *, on_baseline="warn", verbose=None, ): """Remove selected components from the signal. Given the unmixing matrix, transform the data, zero out all excluded components, and inverse-transform the data. This procedure will reconstruct M/EEG signals from which the dynamics described by the excluded components is subtracted. Parameters ---------- inst : instance of Raw, Epochs or Evoked The data to be processed (i.e., cleaned). It will be modified in-place. include : array_like of int The indices referring to columns in the ummixing matrix. The components to be kept. If ``None`` (default), all components will be included (minus those defined in ``ica.exclude`` and the ``exclude`` parameter, see below). exclude : array_like of int The indices referring to columns in the ummixing matrix. The components to be zeroed out. If ``None`` (default) or an empty list, only components from ``ica.exclude`` will be excluded. Else, the union of ``exclude`` and ``ica.exclude`` will be excluded. %(n_pca_components_apply)s start : int | float | None First sample to include. If float, data will be interpreted as time in seconds. If None, data will be used from the first sample. stop : int | float | None Last sample to not include. If float, data will be interpreted as time in seconds. If None, data will be used to the last sample. %(on_baseline_ica)s %(verbose)s Returns ------- out : instance of Raw, Epochs or Evoked The processed data. Notes ----- .. note:: Applying ICA may introduce a DC shift. If you pass baseline-corrected `~mne.Epochs` or `~mne.Evoked` data, the baseline period of the cleaned data may not be of zero mean anymore. If you require baseline-corrected data, apply baseline correction again after cleaning via ICA. A warning will be emitted to remind you of this fact if you pass baseline-corrected data. .. versionchanged:: 0.23 Warn if instance was baseline-corrected. """ _validate_type( inst, (BaseRaw, BaseEpochs, Evoked), "inst", "Raw, Epochs, or Evoked" ) kwargs = dict( include=include, exclude=exclude, n_pca_components=n_pca_components ) if isinstance(inst, BaseRaw): kind, meth = "Raw", self._apply_raw kwargs.update(raw=inst, start=start, stop=stop) elif isinstance(inst, BaseEpochs): kind, meth = "Epochs", self._apply_epochs kwargs.update(epochs=inst) else: # isinstance(inst, Evoked): kind, meth = "Evoked", self._apply_evoked kwargs.update(evoked=inst) _check_compensation_grade( self.info, inst.info, "ICA", kind, ch_names=self.ch_names ) _check_on_missing(on_baseline, "on_baseline", extras=("reapply",)) reapply_baseline = False if isinstance(inst, (BaseEpochs, Evoked)): if getattr(inst, "baseline", None) is not None: if on_baseline == "reapply": reapply_baseline = True else: msg = ( "The data you passed to ICA.apply() was " "baseline-corrected. Please note that ICA can " "introduce DC shifts, therefore you may wish to " "consider baseline-correcting the cleaned data again." ) _on_missing(on_baseline, msg, "on_baseline") logger.info(f"Applying ICA to {kind} instance") out = meth(**kwargs) if reapply_baseline: out.apply_baseline(inst.baseline) return out def _check_exclude(self, exclude): if exclude is None: return list(set(self.exclude)) else: # Allow both self.exclude and exclude to be array-like: return list(set(self.exclude).union(set(exclude))) def _apply_raw(self, raw, include, exclude, n_pca_components, start, stop): """Aux method.""" _check_preload(raw, "ica.apply") start, stop = _check_start_stop(raw, start, stop) picks = pick_types( raw.info, meg=False, include=self.ch_names, exclude="bads", ref_meg=False ) data = raw[picks, start:stop][0] data = self._pick_sources(data, include, exclude, n_pca_components) raw[picks, start:stop] = data return raw def _apply_epochs(self, epochs, include, exclude, n_pca_components): """Aux method.""" _check_preload(epochs, "ica.apply") picks = pick_types( epochs.info, meg=False, ref_meg=False, include=self.ch_names, exclude="bads" ) # special case where epochs come picked but fit was 'unpicked'. if len(picks) != len(self.ch_names): raise RuntimeError( "Epochs don't match fitted data: %i channels " "fitted but %i channels supplied. \nPlease " "provide Epochs compatible with " "ica.ch_names" % (len(self.ch_names), len(picks)) ) data = np.hstack(epochs.get_data(picks)) data = self._pick_sources(data, include, exclude, n_pca_components) # restore epochs, channels, tsl order epochs._data[:, picks] = np.array(np.split(data, len(epochs.events), 1)) epochs.preload = True return epochs def _apply_evoked(self, evoked, include, exclude, n_pca_components): """Aux method.""" picks = pick_types( evoked.info, meg=False, ref_meg=False, include=self.ch_names, exclude="bads" ) # special case where evoked come picked but fit was 'unpicked'. if len(picks) != len(self.ch_names): raise RuntimeError( "Evoked does not match fitted data: %i channels" " fitted but %i channels supplied. \nPlease " "provide an Evoked object that's compatible " "with ica.ch_names" % (len(self.ch_names), len(picks)) ) data = evoked.data[picks] data = self._pick_sources(data, include, exclude, n_pca_components) # restore evoked evoked.data[picks] = data return evoked def _pick_sources(self, data, include, exclude, n_pca_components): """Aux function.""" if n_pca_components is None: n_pca_components = self.n_pca_components data = self._pre_whiten(data) exclude = self._check_exclude(exclude) _n_pca_comp = self._check_n_pca_components(n_pca_components) n_ch, _ = data.shape max_pca_components = self.pca_components_.shape[0] if not self.n_components_ <= _n_pca_comp <= max_pca_components: raise ValueError( f"n_pca_components ({_n_pca_comp}) must be >= " f"n_components_ ({self.n_components_}) and <= " "the total number of PCA components " f"({max_pca_components})." ) logger.info( f" Transforming to ICA space ({self.n_components_} " f"component{_pl(self.n_components_)})" ) # Apply first PCA if self.pca_mean_ is not None: data -= self.pca_mean_[:, None] sel_keep = np.arange(self.n_components_) if include not in (None, []): sel_keep = np.unique(include) elif exclude not in (None, []): sel_keep = np.setdiff1d(np.arange(self.n_components_), exclude) n_zero = self.n_components_ - len(sel_keep) logger.info(f" Zeroing out {n_zero} ICA component{_pl(n_zero)}") # Mixing and unmixing should both be shape (self.n_components_, 2), # and we need to put these into the upper left part of larger mixing # and unmixing matrices of shape (n_ch, _n_pca_comp) pca_components = self.pca_components_[:_n_pca_comp] assert pca_components.shape == (_n_pca_comp, n_ch) assert ( self.unmixing_matrix_.shape == self.mixing_matrix_.shape == (self.n_components_,) * 2 ) unmixing = np.eye(_n_pca_comp) unmixing[: self.n_components_, : self.n_components_] = self.unmixing_matrix_ unmixing = np.dot(unmixing, pca_components) logger.info( f" Projecting back using {_n_pca_comp} " f"PCA component{_pl(_n_pca_comp)}" ) mixing = np.eye(_n_pca_comp) mixing[: self.n_components_, : self.n_components_] = self.mixing_matrix_ mixing = pca_components.T @ mixing assert mixing.shape == unmixing.shape[::-1] == (n_ch, _n_pca_comp) # keep requested components plus residuals (if any) sel_keep = np.concatenate( (sel_keep, np.arange(self.n_components_, _n_pca_comp)) ) proj_mat = np.dot(mixing[:, sel_keep], unmixing[sel_keep, :]) data = np.dot(proj_mat, data) assert proj_mat.shape == (n_ch,) * 2 if self.pca_mean_ is not None: data += self.pca_mean_[:, None] # restore scaling if self.noise_cov is None: # revert standardization data *= self.pre_whitener_ else: data = np.linalg.pinv(self.pre_whitener_, rcond=1e-14) @ data return data @verbose def save(self, fname, *, overwrite=False, verbose=None): """Store ICA solution into a fiff file. Parameters ---------- fname : path-like The absolute path of the file name to save the ICA solution into. The file name should end with ``-ica.fif`` or ``-ica.fif.gz``. %(overwrite)s .. versionadded:: 1.0 %(verbose)s Returns ------- ica : instance of ICA The object. See Also -------- read_ica """ if self.current_fit == "unfitted": raise RuntimeError("No fit available. Please first fit ICA") check_fname( fname, "ICA", ("-ica.fif", "-ica.fif.gz", "_ica.fif", "_ica.fif.gz") ) fname = _check_fname(fname, overwrite=overwrite) logger.info(f"Writing ICA solution to {fname}...") with start_and_end_file(fname) as fid: _write_ica(fid, self) return self def copy(self): """Copy the ICA object. Returns ------- ica : instance of ICA The copied object. """ return deepcopy(self) @copy_function_doc_to_method_doc(plot_ica_components) def plot_components( self, picks=None, ch_type=None, *, inst=None, plot_std=True, reject="auto", sensors=True, show_names=False, contours=6, outlines="head", sphere=None, image_interp=_INTERPOLATION_DEFAULT, extrapolate=_EXTRAPOLATE_DEFAULT, border=_BORDER_DEFAULT, res=64, size=1, cmap="RdBu_r", vlim=(None, None), cnorm=None, colorbar=False, cbar_fmt="%3.2f", axes=None, title=None, nrows="auto", ncols="auto", show=True, image_args=None, psd_args=None, verbose=None, ): return plot_ica_components( self, picks=picks, ch_type=ch_type, inst=inst, plot_std=plot_std, reject=reject, sensors=sensors, show_names=show_names, contours=contours, outlines=outlines, sphere=sphere, image_interp=image_interp, extrapolate=extrapolate, border=border, res=res, size=size, cmap=cmap, vlim=vlim, cnorm=cnorm, colorbar=colorbar, cbar_fmt=cbar_fmt, axes=axes, title=title, nrows=nrows, ncols=ncols, show=show, image_args=image_args, psd_args=psd_args, verbose=verbose, ) @copy_function_doc_to_method_doc(plot_ica_properties) def plot_properties( self, inst, picks=None, axes=None, dB=True, plot_std=True, log_scale=False, topomap_args=None, image_args=None, psd_args=None, figsize=None, show=True, reject="auto", reject_by_annotation=True, *, estimate="power", verbose=None, ): return plot_ica_properties( self, inst, picks=picks, axes=axes, dB=dB, plot_std=plot_std, log_scale=log_scale, topomap_args=topomap_args, image_args=image_args, psd_args=psd_args, figsize=figsize, show=show, reject=reject, reject_by_annotation=reject_by_annotation, estimate=estimate, verbose=verbose, ) @copy_function_doc_to_method_doc(plot_ica_sources) def plot_sources( self, inst, picks=None, start=None, stop=None, title=None, show=True, block=False, show_first_samp=False, show_scrollbars=True, time_format="float", precompute=None, use_opengl=None, *, theme=None, overview_mode=None, splash=True, ): return plot_ica_sources( self, inst=inst, picks=picks, start=start, stop=stop, title=title, show=show, block=block, show_first_samp=show_first_samp, show_scrollbars=show_scrollbars, time_format=time_format, precompute=precompute, use_opengl=use_opengl, theme=theme, overview_mode=overview_mode, splash=splash, ) @copy_function_doc_to_method_doc(plot_ica_scores) def plot_scores( self, scores, exclude=None, labels=None, axhline=None, title="ICA component scores", figsize=None, n_cols=None, show=True, ): return plot_ica_scores( ica=self, scores=scores, exclude=exclude, labels=labels, axhline=axhline, title=title, figsize=figsize, n_cols=n_cols, show=show, ) @copy_function_doc_to_method_doc(plot_ica_overlay) def plot_overlay( self, inst, exclude=None, picks=None, start=None, stop=None, title=None, show=True, n_pca_components=None, *, on_baseline="warn", verbose=None, ): return plot_ica_overlay( self, inst=inst, exclude=exclude, picks=picks, start=start, stop=stop, title=title, show=show, n_pca_components=n_pca_components, on_baseline=on_baseline, verbose=verbose, ) @verbose def _check_n_pca_components(self, _n_pca_comp, verbose=None): """Aux function.""" if isinstance(_n_pca_comp, float): n, ev = _exp_var_ncomp(self.pca_explained_variance_, _n_pca_comp) logger.info( f" Selected {n} PCA components by explained " f"variance ({100 * ev}≥{100 * _n_pca_comp}%)" ) _n_pca_comp = n elif _n_pca_comp is None: _n_pca_comp = self._max_pca_components if _n_pca_comp is None: _n_pca_comp = self.pca_components_.shape[0] elif _n_pca_comp < self.n_components_: _n_pca_comp = self.n_components_ return _n_pca_comp def _exp_var_ncomp(var, n): cvar = np.asarray(var, dtype=np.float64) cvar = cvar.cumsum() cvar /= cvar[-1] # We allow 1., which would give us N+1 n = min((cvar <= n).sum() + 1, len(cvar)) return n, cvar[n - 1] def _check_start_stop(raw, start, stop): """Aux function.""" out = list() for st, none_ in ((start, 0), (stop, raw.n_times)): if st is None: out.append(none_) else: try: out.append(_ensure_int(st)) except TypeError: # not int-like out.append(raw.time_as_index(st)[0]) return out @verbose def ica_find_ecg_events( raw, ecg_source, event_id=999, tstart=0.0, l_freq=5, h_freq=35, qrs_threshold="auto", verbose=None, ): """Find ECG peaks from one selected ICA source. Parameters ---------- raw : instance of Raw Raw object to draw sources from. ecg_source : ndarray ICA source resembling ECG to find peaks from. event_id : int The index to assign to found events. tstart : float Start detection after tstart seconds. Useful when beginning of run is noisy. l_freq : float Low pass frequency. h_freq : float High pass frequency. qrs_threshold : float | str Between 0 and 1. qrs detection threshold. Can also be "auto" to automatically choose the threshold that generates a reasonable number of heartbeats (40-160 beats / min). %(verbose)s Returns ------- ecg_events : array Events. ch_ECG : string Name of channel used. average_pulse : float. Estimated average pulse. """ logger.info("Using ICA source to identify heart beats") # detecting QRS and generating event file ecg_events = qrs_detector( raw.info["sfreq"], ecg_source.ravel(), tstart=tstart, thresh_value=qrs_threshold, l_freq=l_freq, h_freq=h_freq, ) n_events = len(ecg_events) ecg_events = np.c_[ ecg_events + raw.first_samp, np.zeros(n_events), event_id * np.ones(n_events) ] return ecg_events @verbose def ica_find_eog_events( raw, eog_source=None, event_id=998, l_freq=1, h_freq=10, verbose=None ): """Locate EOG artifacts from one selected ICA source. Parameters ---------- raw : instance of Raw The raw data. eog_source : ndarray ICA source resembling EOG to find peaks from. event_id : int The index to assign to found events. l_freq : float Low cut-off frequency in Hz. h_freq : float High cut-off frequency in Hz. %(verbose)s Returns ------- eog_events : array Events. """ eog_events = _find_eog_events( eog_source[np.newaxis], ch_names=None, event_id=event_id, l_freq=l_freq, h_freq=h_freq, sampling_rate=raw.info["sfreq"], first_samp=raw.first_samp, ) return eog_events def _get_target_ch(container, target): """Aux function.""" # auto target selection picks = pick_channels(container.ch_names, include=[target]) ref_picks = pick_types(container.info, meg=False, eeg=False, ref_meg=True) if len(ref_picks) > 0: picks = list(set(picks) - set(ref_picks)) if len(picks) == 0: raise ValueError(f"{target} not in channel list ({container.ch_names})") return picks def _find_sources(sources, target, score_func): """Aux function.""" if isinstance(score_func, str): score_func = get_score_funcs().get(score_func, score_func) if not callable(score_func): raise ValueError(f"{score_func} is not a valid score_func.") scores = ( score_func(sources, target) if target is not None else score_func(sources, 1) ) return scores def _ica_explained_variance(ica, inst, normalize=False): """Check variance accounted for by each component in supplied data. This function is only used for sorting the components. Parameters ---------- ica : ICA Instance of `mne.preprocessing.ICA`. inst : Raw | Epochs | Evoked Data to explain with ICA. Instance of Raw, Epochs or Evoked. normalize : bool Whether to normalize the variance. Returns ------- var : array Variance explained by each component. """ # check if ica is ICA and whether inst is Raw or Epochs if not isinstance(ica, ICA): raise TypeError("first argument must be an instance of ICA.") if not isinstance(inst, (BaseRaw, BaseEpochs, Evoked)): raise TypeError( "second argument must an instance of either Raw, Epochs or Evoked." ) source_data = _get_inst_data(ica.get_sources(inst)) # if epochs - reshape to channels x timesamples if isinstance(inst, BaseEpochs): n_epochs, n_chan, n_samp = source_data.shape source_data = source_data.transpose(1, 0, 2).reshape( (n_chan, n_epochs * n_samp) ) n_chan, n_samp = source_data.shape var = ( np.sum(ica.mixing_matrix_**2, axis=0) * np.sum(source_data**2, axis=1) / (n_chan * n_samp - 1) ) if normalize: var /= var.sum() return var def _sort_components(ica, order, copy=True): """Change the order of components in ica solution.""" assert ica.n_components_ == len(order) if copy: ica = ica.copy() # reorder components ica.mixing_matrix_ = ica.mixing_matrix_[:, order] ica.unmixing_matrix_ = ica.unmixing_matrix_[order, :] # reorder labels, excludes etc. if isinstance(order, np.ndarray): order = list(order) if ica.exclude: ica.exclude = [order.index(ic) for ic in ica.exclude] for k in ica.labels_.keys(): ica.labels_[k] = [order.index(ic) for ic in ica.labels_[k]] return ica def _serialize(dict_, outer_sep=";", inner_sep=":"): """Aux function.""" s = [] for key, value in dict_.items(): if callable(value): value = value.__name__ elif isinstance(value, Integral): value = int(value) elif isinstance(value, dict): # py35 json does not support numpy int64 for subkey, subvalue in value.items(): if isinstance(subvalue, list): if len(subvalue) > 0: if isinstance(subvalue[0], (int, np.integer)): value[subkey] = [int(i) for i in subvalue] for cls in (np.random.RandomState, Covariance): if isinstance(value, cls): value = cls.__name__ s.append(key + inner_sep + json.dumps(value)) return outer_sep.join(s) def _deserialize(str_, outer_sep=";", inner_sep=":"): """Aux Function.""" out = {} for mapping in str_.split(outer_sep): k, v = mapping.split(inner_sep, 1) out[k] = json.loads(v) return out def _write_ica(fid, ica): """Write an ICA object. Parameters ---------- fid: file The file descriptor ica: The instance of ICA to write """ ica_init = dict( noise_cov=ica.noise_cov, n_components=ica.n_components, n_pca_components=ica.n_pca_components, max_pca_components=ica._max_pca_components, current_fit=ica.current_fit, allow_ref_meg=ica.allow_ref_meg, ) if ica.info is not None: start_block(fid, FIFF.FIFFB_MEAS) write_id(fid, FIFF.FIFF_BLOCK_ID) if ica.info["meas_id"] is not None: write_id(fid, FIFF.FIFF_PARENT_BLOCK_ID, ica.info["meas_id"]) # Write measurement info write_meas_info(fid, ica.info) end_block(fid, FIFF.FIFFB_MEAS) start_block(fid, FIFF.FIFFB_MNE_ICA) # ICA interface params write_string(fid, FIFF.FIFF_MNE_ICA_INTERFACE_PARAMS, _serialize(ica_init)) # Channel names if ica.ch_names is not None: write_name_list(fid, FIFF.FIFF_MNE_ROW_NAMES, ica.ch_names) # samples on fit n_samples = getattr(ica, "n_samples_", None) ica_misc = { "n_samples_": (None if n_samples is None else int(n_samples)), "labels_": getattr(ica, "labels_", None), "method": getattr(ica, "method", None), "n_iter_": getattr(ica, "n_iter_", None), "fit_params": getattr(ica, "fit_params", None), } # ICA misc params write_string(fid, FIFF.FIFF_MNE_ICA_MISC_PARAMS, _serialize(ica_misc)) # Whitener write_double_matrix(fid, FIFF.FIFF_MNE_ICA_WHITENER, ica.pre_whitener_) # PCA components_ write_double_matrix(fid, FIFF.FIFF_MNE_ICA_PCA_COMPONENTS, ica.pca_components_) # PCA mean_ write_double_matrix(fid, FIFF.FIFF_MNE_ICA_PCA_MEAN, ica.pca_mean_) # PCA explained_variance_ write_double_matrix( fid, FIFF.FIFF_MNE_ICA_PCA_EXPLAINED_VAR, ica.pca_explained_variance_ ) # ICA unmixing write_double_matrix(fid, FIFF.FIFF_MNE_ICA_MATRIX, ica.unmixing_matrix_) # Write bad components write_int(fid, FIFF.FIFF_MNE_ICA_BADS, list(ica.exclude)) # Write reject_ if ica.reject_ is not None: write_string( fid, FIFF.FIFF_MNE_EPOCHS_REJECT_FLAT, json.dumps(dict(reject=ica.reject_)) ) # Done! end_block(fid, FIFF.FIFFB_MNE_ICA) @verbose def read_ica(fname, verbose=None): """Restore ICA solution from fif file. Parameters ---------- fname : path-like Absolute path to fif file containing ICA matrices. The file name should end with -ica.fif or -ica.fif.gz. %(verbose)s Returns ------- ica : instance of ICA The ICA estimator. """ check_fname(fname, "ICA", ("-ica.fif", "-ica.fif.gz", "_ica.fif", "_ica.fif.gz")) logger.info(f"Reading {fname} ...") fid, tree, _ = fiff_open(fname) try: # we used to store bads that weren't part of the info... info, _ = read_meas_info(fid, tree, clean_bads=True) except ValueError: logger.info( "Could not find the measurement info. \n" "Functionality requiring the info won't be" " available." ) info = None ica_data = dir_tree_find(tree, FIFF.FIFFB_MNE_ICA) if len(ica_data) == 0: ica_data = dir_tree_find(tree, 123) # Constant 123 Used before v 0.11 if len(ica_data) == 0: fid.close() raise ValueError("Could not find ICA data") my_ica_data = ica_data[0] ica_reject = None for d in my_ica_data["directory"]: kind = d.kind pos = d.pos if kind == FIFF.FIFF_MNE_ICA_INTERFACE_PARAMS: tag = read_tag(fid, pos) ica_init = tag.data elif kind == FIFF.FIFF_MNE_ROW_NAMES: tag = read_tag(fid, pos) ch_names = tag.data elif kind == FIFF.FIFF_MNE_ICA_WHITENER: tag = read_tag(fid, pos) pre_whitener = tag.data elif kind == FIFF.FIFF_MNE_ICA_PCA_COMPONENTS: tag = read_tag(fid, pos) pca_components = tag.data elif kind == FIFF.FIFF_MNE_ICA_PCA_EXPLAINED_VAR: tag = read_tag(fid, pos) pca_explained_variance = tag.data elif kind == FIFF.FIFF_MNE_ICA_PCA_MEAN: tag = read_tag(fid, pos) pca_mean = tag.data elif kind == FIFF.FIFF_MNE_ICA_MATRIX: tag = read_tag(fid, pos) unmixing_matrix = tag.data elif kind == FIFF.FIFF_MNE_ICA_BADS: tag = read_tag(fid, pos) exclude = tag.data elif kind == FIFF.FIFF_MNE_ICA_MISC_PARAMS: tag = read_tag(fid, pos) ica_misc = tag.data elif kind == FIFF.FIFF_MNE_EPOCHS_REJECT_FLAT: tag = read_tag(fid, pos) ica_reject = json.loads(tag.data)["reject"] fid.close() ica_init, ica_misc = (_deserialize(k) for k in (ica_init, ica_misc)) n_pca_components = ica_init.pop("n_pca_components") current_fit = ica_init.pop("current_fit") max_pca_components = ica_init.pop("max_pca_components") method = ica_misc.get("method", "fastica") if method in _KNOWN_ICA_METHODS: ica_init["method"] = method if ica_init["noise_cov"] == Covariance.__name__: logger.info("Reading whitener drawn from noise covariance ...") logger.info("Now restoring ICA solution ...") # make sure dtypes are np.float64 to satisfy fast_dot def f(x): return x.astype(np.float64) ica_init = { k: v for k, v in ica_init.items() if k in signature(ICA.__init__).parameters } ica = ICA(**ica_init) ica.current_fit = current_fit ica.ch_names = ch_names.split(":") if n_pca_components is not None and not isinstance(n_pca_components, int_like): n_pca_components = np.float64(n_pca_components) ica.n_pca_components = n_pca_components ica.pre_whitener_ = f(pre_whitener) ica.pca_mean_ = f(pca_mean) ica.pca_components_ = f(pca_components) ica.n_components_ = unmixing_matrix.shape[0] ica._max_pca_components = max_pca_components ica._update_ica_names() ica.pca_explained_variance_ = f(pca_explained_variance) ica.unmixing_matrix_ = f(unmixing_matrix) ica._update_mixing_matrix() ica.exclude = [] if exclude is None else list(exclude) ica.info = info if "n_samples_" in ica_misc: ica.n_samples_ = ica_misc["n_samples_"] if "labels_" in ica_misc: labels_ = ica_misc["labels_"] if labels_ is not None: ica.labels_ = labels_ if "method" in ica_misc: ica.method = ica_misc["method"] if "n_iter_" in ica_misc: ica.n_iter_ = ica_misc["n_iter_"] if "fit_params" in ica_misc: ica.fit_params = ica_misc["fit_params"] ica.reject_ = ica_reject logger.info("Ready.") return ica _ica_node = namedtuple("Node", "name target score_func criterion") @verbose def _band_pass_filter(inst, sources, target, l_freq, h_freq, verbose=None): """Optionally band-pass filter the data.""" if l_freq is not None and h_freq is not None: logger.info("... filtering ICA sources") # use FIR here, steeper is better kw = dict( phase="zero-double", filter_length="10s", fir_window="hann", l_trans_bandwidth=0.5, h_trans_bandwidth=0.5, fir_design="firwin2", ) sources = filter_data(sources, inst.info["sfreq"], l_freq, h_freq, **kw) logger.info("... filtering target") target = filter_data(target, inst.info["sfreq"], l_freq, h_freq, **kw) elif l_freq is not None or h_freq is not None: raise ValueError("Must specify both pass bands") return sources, target # ############################################################################# # CORRMAP def _find_max_corrs(all_maps, target, threshold): """Compute correlations between template and target components.""" # Following Fig.2 from: # https://www.sciencedirect.com/science/article/abs/pii/S1388245709002338 # > ... inverse weights (i.e., IC maps) from a selected template IC are # > correlated with all ICs from all datasets ... all_corrs = [compute_corr(target, subj_maps.T) for subj_maps in all_maps] abs_corrs = [np.abs(a) for a in all_corrs] corr_polarities = [np.sign(a) for a in all_corrs] del all_corrs # > selection of X ICs from each dataset with highest absolute # > correlation >= TH # # subj_idxs is a list of indices for each subject that exceeded the threshold: if threshold <= 1: subj_idxs = [list(np.nonzero(s_corr > threshold)[0]) for s_corr in abs_corrs] else: subj_idxs = [ list(_find_outliers(s_corr, threshold=threshold)) for s_corr in abs_corrs ] # > The mean correlation of a resulting cluster is then computed via # > Fisher’s z transform, to account for the non-normal distribution of # > correlation values. # # Here we just use the median rather than the (transformed-back) mean of # the (Fisher z-transformed) correlations: am = np.concatenate( [abs_corr[subj_idx] for abs_corr, subj_idx in zip(abs_corrs, subj_idxs)] ) if len(am) == 0: return [], 0, 0, [] median_corr_with_target = np.median(am) # > Next, an average cluster map is calculated, after inversion of those # > ICs showing a negative correlation (sign ambiguity problem) and root # > mean square (RMS) normalization of each individual IC. # # Which is this (rms=Frobenius norm=np.linalg.norm): newtarget = sum( subj_maps[idx] * (pols[idx] / np.linalg.norm(subj_maps[idx])) for subj_maps, pols, subj_idx in zip(all_maps, corr_polarities, subj_idxs) for idx in subj_idx ) newtarget /= len(am) # And we also compute the similarity between this new map and our original # target map sim_i_o = np.abs(np.corrcoef(target, newtarget)[1, 0]) return newtarget, median_corr_with_target, sim_i_o, subj_idxs @verbose def corrmap( icas, template, threshold="auto", label=None, ch_type="eeg", *, sensors=True, show_names=False, contours=6, outlines="head", sphere=None, image_interp=_INTERPOLATION_DEFAULT, extrapolate=_EXTRAPOLATE_DEFAULT, border=_BORDER_DEFAULT, cmap=None, plot=True, show=True, verbose=None, ): """Find similar Independent Components across subjects by map similarity. Corrmap :footcite:p:`CamposViolaEtAl2009` identifies the best group match to a supplied template. Typically, feed it a list of fitted ICAs and a template IC, for example, the blink for the first subject, to identify specific ICs across subjects. The specific procedure consists of two iterations. In a first step, the maps best correlating with the template are identified. In the next step, the analysis is repeated with the mean of the maps identified in the first stage. Run with ``plot`` and ``show`` set to ``True`` and ``label=False`` to find good parameters. Then, run with labelling enabled to apply the labelling in the IC objects. (Running with both ``plot`` and ``labels`` off does nothing.) Outputs a list of fitted ICAs with the indices of the marked ICs in a specified field. The original Corrmap website: www.debener.de/corrmap/corrmapplugin1.html Parameters ---------- icas : list of mne.preprocessing.ICA A list of fitted ICA objects. template : tuple | np.ndarray, shape (n_components,) Either a tuple with two elements (int, int) representing the list indices of the set from which the template should be chosen, and the template. E.g., if template=(1, 0), the first IC of the 2nd ICA object is used. Or a numpy array whose size corresponds to each IC map from the supplied maps, in which case this map is chosen as the template. threshold : "auto" | list of float | float Correlation threshold for identifying ICs If "auto", search for the best map by trying all correlations between 0.6 and 0.95. In the original proposal, lower values are considered, but this is not yet implemented. If list of floats, search for the best map in the specified range of correlation strengths. As correlation values, must be between 0 and 1 If float > 0, select ICs correlating better than this. If float > 1, use z-scoring to identify ICs within subjects (not in original Corrmap) Defaults to "auto". label : None | str If not None, categorised ICs are stored in a dictionary ``labels_`` under the given name. Preexisting entries will be appended to (excluding repeats), not overwritten. If None, a dry run is performed and the supplied ICs are not changed. ch_type : 'mag' | 'grad' | 'planar1' | 'planar2' | 'eeg' The channel type to plot. Defaults to 'eeg'. %(sensors_topomap)s %(show_names_topomap)s %(contours_topomap)s %(outlines_topomap)s %(sphere_topomap_auto)s %(image_interp_topomap)s .. versionadded:: 1.2 %(extrapolate_topomap)s .. versionadded:: 1.2 %(border_topomap)s .. versionadded:: 1.2 %(cmap_topomap_simple)s plot : bool Should constructed template and selected maps be plotted? Defaults to True. %(show)s %(verbose)s Returns ------- template_fig : Figure Figure showing the template. labelled_ics : Figure Figure showing the labelled ICs in all ICA decompositions. References ---------- .. footbibliography:: """ if not isinstance(plot, bool): raise ValueError("`plot` must be of type `bool`") same_chans = _check_all_same_channel_names(icas) if same_chans is False: raise ValueError( "Not all ICA instances have the same channel names. " "Corrmap requires all instances to have the same " "montage. Consider interpolating bad channels before " "running ICA." ) threshold_extra = "" if threshold == "auto": threshold = np.arange(60, 95, dtype=np.float64) / 100.0 threshold_extra = ' ("auto")' all_maps = [ica.get_components().T for ica in icas] # check if template is an index to one IC in one ICA object, or an array if len(template) == 2: target = all_maps[template[0]][template[1]] is_subject = True elif template.ndim == 1 and len(template) == all_maps[0].shape[1]: target = template is_subject = False else: raise ValueError( "`template` must be a length-2 tuple or an array the " "size of the ICA maps." ) template_fig, labelled_ics = None, None if plot is True: if is_subject: # plotting from an ICA object ttl = f"Template from subj. {template[0]}" template_fig = icas[template[0]].plot_components( picks=template[1], ch_type=ch_type, title=ttl, outlines=outlines, cmap=cmap, contours=contours, show=show, sphere=sphere, ) else: # plotting an array template_fig = _plot_corrmap( [template], [0], [0], ch_type, icas[0].copy(), "Template", outlines=outlines, cmap=cmap, contours=contours, image_interp=image_interp, extrapolate=extrapolate, border=border, show=show, template=True, sphere=sphere, ) template_fig.canvas.draw() # first run: use user-selected map threshold = np.atleast_1d(np.array(threshold, float)).ravel() threshold_err = ( "No component detected using when z-scoring " f"threshold{threshold_extra} {threshold}, consider using a more lenient " "threshold" ) if len(all_maps) == 0: raise RuntimeError(threshold_err) paths = [_find_max_corrs(all_maps, target, t) for t in threshold] # find iteration with highest avg correlation with target new_target, _, _, _ = paths[np.argmax([path[2] for path in paths])] # second run: use output from first run if len(all_maps) == 0 or len(new_target) == 0: raise RuntimeError(threshold_err) paths = [_find_max_corrs(all_maps, new_target, t) for t in threshold] del new_target # find iteration with highest avg correlation with target _, median_corr, _, max_corrs = paths[np.argmax([path[1] for path in paths])] allmaps, indices, subjs, nones = (list() for _ in range(4)) logger.info(f"Median correlation with constructed map: {median_corr:0.3f}") del median_corr if plot is True: logger.info("Displaying selected ICs per subject.") for ii, (ica, max_corr) in enumerate(zip(icas, max_corrs)): if len(max_corr) > 0: if isinstance(max_corr[0], np.ndarray): max_corr = max_corr[0] if label is not None: ica.labels_[label] = list( set(list(max_corr) + ica.labels_.get(label, list())) ) if plot is True: allmaps.extend(ica.get_components()[:, max_corr].T) subjs.extend([ii] * len(max_corr)) indices.extend(max_corr) else: if (label is not None) and (label not in ica.labels_): ica.labels_[label] = list() nones.append(ii) if len(nones) == 0: logger.info("At least 1 IC detected for each subject.") else: logger.info( f"No maps selected for subject{_pl(nones)} {nones}, " "consider a more liberal threshold." ) if plot is True: labelled_ics = _plot_corrmap( allmaps, subjs, indices, ch_type, ica, label, outlines=outlines, cmap=cmap, sensors=sensors, contours=contours, sphere=sphere, image_interp=image_interp, extrapolate=extrapolate, border=border, show=show, show_names=show_names, ) return template_fig, labelled_ics else: return None @verbose def read_ica_eeglab(fname, *, montage_units="auto", verbose=None): """Load ICA information saved in an EEGLAB .set file. Parameters ---------- fname : path-like Complete path to a ``.set`` EEGLAB file that contains an ICA object. %(montage_units)s .. versionadded:: 1.6 %(verbose)s Returns ------- ica : instance of ICA An ICA object based on the information contained in the input file. """ eeg = _check_load_mat(fname, None) info, eeg_montage, _ = _get_info(eeg, eog=(), montage_units=montage_units) info.set_montage(eeg_montage) pick_info(info, np.round(eeg["icachansind"]).astype(int) - 1, copy=False) rank = eeg.icasphere.shape[0] n_components = eeg.icaweights.shape[0] ica = ICA(method="imported_eeglab", n_components=n_components) ica.current_fit = "eeglab" ica.ch_names = info["ch_names"] ica.n_pca_components = None ica.n_components_ = n_components n_ch = len(ica.ch_names) assert len(eeg.icachansind) == n_ch ica.pre_whitener_ = np.ones((n_ch, 1)) ica.pca_mean_ = np.zeros(n_ch) assert eeg.icasphere.shape[1] == n_ch assert eeg.icaweights.shape == (n_components, rank) # When PCA reduction is used in EEGLAB, runica returns # weights= weights*sphere*eigenvectors(:,1:ncomps)'; # sphere = eye(urchans). When PCA reduction is not used, we have: # # eeg.icawinv == pinv(eeg.icaweights @ eeg.icasphere) # # So in either case, we can use SVD to get our square whitened # weights matrix (u * s) and our PCA vectors (v) back: use = eeg.icaweights @ eeg.icasphere use_check = pinv(eeg.icawinv) if not np.allclose(use, use_check, rtol=1e-6): warn( "Mismatch between icawinv and icaweights @ icasphere from EEGLAB " "possibly due to ICA component removal, assuming icawinv is " "correct" ) use = use_check u, s, v = _safe_svd(use, full_matrices=False) ica.unmixing_matrix_ = u * s ica.pca_components_ = v ica.pca_explained_variance_ = s * s ica.info = info ica._update_mixing_matrix() ica._update_ica_names() ica.reject_ = None return ica