oneflow.nn.Softmax

class oneflow.nn.Softmax(dim: Optional[int] = None)

Applies the Softmax function to an n-dimensional input Tensor rescaling them so that the elements of the n-dimensional output Tensor lie in the range [0,1] and sum to 1.

Softmax is defined as:

\[\text{Softmax}(x_{i}) = \frac{\exp(x_i)}{\sum_j \exp(x_j)}\]

When the input Tensor is a sparse tensor then the unspecifed values are treated as -inf.

Shape:

• Input: \((*)\) where * means, any number of additional dimensions

• Output: \((*)\), same shape as the input

Returns

a Tensor of the same dimension and shape as the input with values in the range [0, 1]

Parameters

dim (int) – A dimension along which Softmax will be computed (so every slice along dim will sum to 1).

For example:

>>> import numpy as np
>>> import oneflow as flow

>>> m = flow.nn.Softmax(dim = 2)
>>> x = flow.Tensor(
...    np.array(
...        [[[-0.46716809,  0.40112534,  0.61984003],
...        [-1.31244969, -0.42528763,  1.47953856]]]
...    )
... )
>>> out = m(x)
>>> out
tensor([[[0.1575, 0.3754, 0.4671],
         [0.0507, 0.1230, 0.8263]]], dtype=oneflow.float32)