spyrit.core.prep.UnsplitRescale.sigma

UnsplitRescale.sigma(y: tensor) → tensor

Rescale the variance

\[\text{var}(m) = \frac{\text{var}(y_+) + \text{var}(y_-)}{\alpha^2}\]

Args:

v (torch.tensor): Variance of \(y\) with shape \((*, 2M)\).

Returns:

torch.tensor: Variance of \(m\) with shape \((*, M)\).