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Csd

Namespace: UTILSLIB  ·  Library: Utilities Library

#include <utils/csd.h>

class UTILSLIB::Csd

Cross-Spectral Density (CSD) estimator.

Provides three methods for computing the CSD matrix between channels: multitaper (DPSS tapers), Fourier (Welch-style segmented), and Morlet wavelet.

// Multitaper CSD: 600 Hz data, 0–60 Hz band, half-bandwidth 4
CsdResult r = Csd::computeMultitaper(matData, 600.0, 0.0, 60.0, 4.0);
// r.matCsd       → n_ch × n_ch mean CSD
// r.csdByFreq[k] → n_ch × n_ch at frequency r.vecFreqs[k]

Static Methods​

computeMultitaper(matData, sfreq, fmin, fmax, halfBandwidth, nTapers)​

Compute CSD using multitaper (DPSS) spectral estimation.

Parameters:

  • matData : const Eigen::MatrixXd & Data matrix (n_channels × n_samples).

  • sfreq : double Sampling frequency in Hz.

  • fmin : double Minimum frequency of interest in Hz (default 0).

  • fmax : double Maximum frequency in Hz; -1 → Nyquist (default -1).

  • halfBandwidth : double Half-bandwidth parameter (NW) for DPSS tapers (default 4).

  • nTapers : int Number of tapers; -1 → floor(2*halfBandwidth - 1) (default -1).

Returns:

  • CsdResult — CsdResult with per-frequency and mean CSD matrices.

computeFourier(matData, sfreq, fmin, fmax, nFft, overlap)​

Compute CSD using Welch-style Fourier segmented estimation.

Parameters:

  • matData : const Eigen::MatrixXd & Data matrix (n_channels × n_samples).

  • sfreq : double Sampling frequency in Hz.

  • fmin : double Minimum frequency of interest in Hz (default 0).

  • fmax : double Maximum frequency in Hz; -1 → Nyquist (default -1).

  • nFft : int FFT / segment length in samples (default 256).

  • overlap : double Fractional overlap between adjacent segments, in [0, 1) (default 0.5).

Returns:

  • CsdResult — CsdResult with per-frequency and mean CSD matrices.

computeMorlet(matData, sfreq, frequencies, nCycles)​

Compute CSD using Morlet wavelet convolution.

Parameters:

  • matData : const Eigen::MatrixXd & Data matrix (n_channels × n_samples).

  • sfreq : double Sampling frequency in Hz.

  • frequencies : const Eigen::RowVectorXd & Target frequencies in Hz.

  • nCycles : int Number of cycles in the Morlet wavelet (default 7).

Returns:

  • CsdResult — CsdResult with one CSD matrix per target frequency.

Authors of this file​