getipsph

getipsph(x, m=None)

Return an EEGLAB-compatible sphering or quasi-sphering matrix.

Parameters:

• x (Any) – Channel-major data with shape (channels, samples).

• m (int | None) – Output dimensionality. The default preserves all channels.

Returns:

A matrix with shape (m, channels) whose product with centered x has identity covariance when the retained covariance is full rank.

Return type:

ndarray