Applies a softmin function.
nnf_softmin(input, dim, dtype = NULL)(Tensor) input
(int) A dimension along which softmin will be computed (so every slice along dim will sum to 1).
(torch.dtype, optional) the desired data type of returned tensor. If specified, the input tensor is casted to dtype before the operation is performed.
This is useful for preventing data type overflows. Default: NULL.
Note that
$$Softmin(x) = Softmax(-x)$$.
See nnf_softmax definition for mathematical formula.