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LogSoftmax module

Source: R/nn-activation.R
nn_log_softmax.Rd

Applies the \(\log(\mbox{Softmax}(x))\) function to an n-dimensional input Tensor. The LogSoftmax formulation can be simplified as:

Usage

nn_log_softmax(dim)

Arguments

dim

(int): A dimension along which LogSoftmax will be computed.

Value

a Tensor of the same dimension and shape as the input with values in the range [-inf, 0)

Details

$$ \mbox{LogSoftmax}(x_{i}) = \log\left(\frac{\exp(x_i) }{ \sum_j \exp(x_j)} \right) $$

Shape

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

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

Examples

if (torch_is_installed()) {
m <- nn_log_softmax(1)
input <- torch_randn(2, 3)
output <- m(input)
}