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Sigmoid

class torch.nn.modules.activation.Sigmoid(*args, **kwargs) [source]

Applies the Sigmoid function element-wise.

Sigmoid(x)=σ(x)=11+exp(x)\text{Sigmoid}(x) = \sigma(x) = \frac{1}{1 + \exp(-x)}
Shape:
  • Input: ()(*), where * means any number of dimensions.
  • Output: ()(*), same shape as the input.
../_images/Sigmoid.png

Examples:

>>> m = nn.Sigmoid()
>>> input = torch.randn(2)
>>> output = m(input)
forward(input) [source]

Runs the forward pass.

Return type

Tensor

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https://docs.pytorch.org/docs/2.9/generated/torch.nn.modules.activation.Sigmoid.html