mne.time_frequency.psd_array_welch¶

mne.time_frequency.psd_array_welch(x, sfreq, fmin=0, fmax=inf, n_fft=256, n_overlap=0, n_per_seg=None, n_jobs=1, verbose=None)[source]¶

Compute power spectral density (PSD) using Welch’s method.

Parameters:

Parameters:	x : array, shape=(…, n_times) The data to compute PSD from. sfreq : float The sampling frequency. fmin : float The lower frequency of interest. fmax : float The upper frequency of interest. n_fft : int The length of FFT used, must be `>= n_per_seg` (default: 256). The segments will be zero-padded if `n_fft > n_per_seg`. n_overlap : int The number of points of overlap between segments. Will be adjusted to be <= n_per_seg. The default value is 0. n_per_seg : int \| None Length of each Welch segment. The smaller it is with respect to the signal length the smoother are the PSDs. Defaults to None, which sets n_per_seg equal to n_fft. n_jobs : int Number of CPUs to use in the computation. verbose : bool, str, int, or None If not None, override default verbose level (see `mne.verbose()` and Logging documentation for more).
Returns:	psds : ndarray, shape (…, n_freqs) or The power spectral densities. All dimensions up to the last will be the same as input. freqs : ndarray, shape (n_freqs,) The frequencies.

x : array, shape=(…, n_times)

The data to compute PSD from.

sfreq : float

The sampling frequency.

fmin : float

The lower frequency of interest.

fmax : float

The upper frequency of interest.

n_fft : int

The length of FFT used, must be >= n_per_seg (default: 256). The segments will be zero-padded if n_fft > n_per_seg.

n_overlap : int

The number of points of overlap between segments. Will be adjusted to be <= n_per_seg. The default value is 0.

n_per_seg : int | None

Length of each Welch segment. The smaller it is with respect to the signal length the smoother are the PSDs. Defaults to None, which sets n_per_seg equal to n_fft.

n_jobs : int

Number of CPUs to use in the computation.

verbose : bool, str, int, or None

If not None, override default verbose level (see mne.verbose() and Logging documentation for more).

Returns:

psds : ndarray, shape (…, n_freqs) or

The power spectral densities. All dimensions up to the last will be the same as input.

freqs : ndarray, shape (n_freqs,)

The frequencies.

Notes

New in version 0.14.0.