tfmri.math.block_soft_threshold

block_soft_threshold(x, threshold, name=None)

Block soft thresholding operator.

In the context of proximal gradient methods, this function is the proximal operator of \(f = {\left\| x \right\|}_{2}\) (L2 norm).

Parameters

• x – A Tensor of shape [..., n].

• threshold – A float.

• name – A name for this operation (optional).

Returns

A Tensor of shape [..., n] and same dtype as x.