pyriemann.utils.mean.mean_harmonic

pyriemann.utils.mean.mean_harmonic(covmats, sample_weight=None)

Harmonic mean of SPD matrices.

\[\mathbf{C} = \left(\frac{1}{m} \sum_i {\mathbf{C}_i}^{-1}\right)^{-1}\]
Parameters
covmatsndarray, shape (n_matrices, n_channels, n_channels)

Set of SPD matrices.

sample_weightNone | ndarray, shape (n_matrices,), default=None

Weights for each matrix. If None, it uses equal weights.

Returns
Cndarray, shape (n_channels, n_channels)

Harmonic mean.