pyriemann.utils.tangentspace.exp_map_logeuclid

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

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

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

\[\mathbf{X}_\text{original} = \exp(\mathbf{X} + \log(\mathbf{C}_\text{ref}))\]

Parameters:

Xndarray, shape (…, n, n)

Matrices in tangent space.

Crefndarray, shape (n, n)

Reference SPD/HPD matrix.

Returns:

X_originalndarray, shape (…, n, n)

Matrices in SPD/HPD manifold.

Notes

New in version 0.4.