pyriemann.utils.tangentspace.log_map_logeuclid

pyriemann.utils.tangentspace.log_map_logeuclid(X, Cref)

Project SPD matrices in tangent space by Log-Euclidean logarithmic map.

The projection of a SPD matrix X in the tangent space by Log-Euclidean logarithmic map according to a reference matrix \(\mathbf{C}_\text{ref}\) is:

\[\mathbf{X}_\text{new} = \log(\mathbf{X}) - \log(\mathbf{C}_\text{ref})\]

Parameters

Xndarray, shape (…, n_channels, n_channels)

SPD matrices.

Crefndarray, shape (n_channels, n_channels)

The reference SPD matrix.

Returns

X_newndarray, shape (…, n_channels, n_channels)

SPD matrices projected in tangent space.

Notes

New in version 0.3.1.