pyriemann.utils.tangentspace.exp_map_logeuclid

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

Project matrices back to SPD manifold by Log-Euclidean exponential map.

The projection of a matrix X back to the SPD manifold with Log-Euclidean exponential map according to a reference matrix \(\mathbf{C}_\text{ref}\) is:

\[\mathbf{X}_\text{original} = \exp(\mathbf{X} + \log(\mathbf{C}_\text{ref}))\]
Parameters
Xndarray, shape (…, n_channels, n_channels)

Matrices in tangent space.

Crefndarray, shape (n_channels, n_channels)

The reference SPD matrix.

Returns
X_originalndarray, shape (…, n_channels, n_channels)

SPD matrices.

Notes

New in version 0.3.1.