UTILSLIB::Xdawn Class Reference

Event-related response enhancement with xDAWN spatial filtering. More...

#include <xdawn.h>

Static Public Member Functions
static XdawnResult	fit (const QVector< MNELIB::MNEEpochData > &epochs, int iTargetEvent=1, int nComponents=2, double dReg=1e-6)
static Eigen::MatrixXd	apply (const Eigen::MatrixXd &matEpoch, const XdawnResult &result)
static Eigen::MatrixXd	denoise (const Eigen::MatrixXd &matEpoch, const XdawnResult &result, int nComponents=-1)
static QVector< MNELIB::MNEEpochData >	denoiseEpochs (const QVector< MNELIB::MNEEpochData > &epochs, const XdawnResult &result, int nComponents=-1)

Detailed Description

Event-related response enhancement with xDAWN spatial filtering.

Typical usage:

auto xd = Xdawn::fit(epochs, 1, 4);
Eigen::MatrixXd comp = Xdawn::apply(epoch.epoch, xd);      // 4 x n_samples
Eigen::MatrixXd den  = Xdawn::denoise(epoch.epoch, xd, 2); // n_channels x n_samples

Definition at line 95 of file xdawn.h.

Member Function Documentation

apply()

MatrixXd Xdawn::apply ( const Eigen::MatrixXd & matEpoch, const XdawnResult & result )

static

Project one epoch into xDAWN component space.

Parameters

[in]	matEpoch	Epoch data (n_channels x n_samples).
[in]	result	Result from fit().

Returns

Component activations (n_components x n_samples).

Definition at line 236 of file xdawn.cpp.

denoise()

MatrixXd Xdawn::denoise ( const Eigen::MatrixXd & matEpoch, const XdawnResult & result, int nComponents = -1 )

static

Reconstruct one epoch from the first nComponents xDAWN components.

If nComponents <= 0 or exceeds the fitted dimensionality, all fitted components are used.

Parameters

[in]	matEpoch	Epoch data (n_channels x n_samples).
[in]	result	Result from fit().
[in]	nComponents	Number of leading xDAWN components to keep.

Returns

Denoised epoch (n_channels x n_samples).

Definition at line 252 of file xdawn.cpp.

denoiseEpochs()

QVector< MNEEpochData > Xdawn::denoiseEpochs ( const QVector< MNELIB::MNEEpochData > & epochs, const XdawnResult & result, int nComponents = -1 )

static

Apply denoise() to all epochs in the vector, preserving metadata.

Parameters

[in]	epochs	Input epochs.
[in]	result	Result from fit().
[in]	nComponents	Number of leading xDAWN components to keep.

Returns

Copy of the input epochs with denoised epoch matrices.

Definition at line 275 of file xdawn.cpp.

fit()

XdawnResult Xdawn::fit ( const QVector< MNELIB::MNEEpochData > & epochs, int iTargetEvent = 1, int nComponents = 2, double dReg = 1e-6 )

static

Fit xDAWN spatial filters for a target event code.

Uses non-rejected epochs only. The target signal covariance is estimated from the average of epochs whose MNEEpochData::event equals iTargetEvent. The noise covariance is estimated from residuals around the class-wise average for each event type.

Parameters

[in]	epochs	Input epochs.
[in]	iTargetEvent	Event code whose ERP/ERF should be enhanced.
[in]	nComponents	Number of xDAWN components to retain.
[in]	dReg	Relative diagonal regularisation added to the noise covariance.

Returns

XdawnResult containing filters, patterns, and covariances.

Definition at line 90 of file xdawn.cpp.

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The documentation for this class was generated from the following files:

• src/libraries/dsp/xdawn.h
• src/libraries/dsp/xdawn.cpp