Versioned name : Elu-1

Category : Activation function

Short description : Exponential linear unit element-wise activation function.

Detailed Description

Elu operation is introduced in this article. It performs element-wise activation function on a given input tensor, based on the following mathematical formula:

\[\begin{split}Elu(x) = \left\{\begin{array}{r} x \qquad \mbox{if } x > 0 \\ \alpha(e^{x} - 1) \quad \mbox{if } x \leq 0 \end{array}\right.\end{split}\]

where α corresponds to alpha attribute.

Elu is equivalent to ReLU operation when alpha is equal to zero.


  • alpha

    • Description : scale for the negative factor

    • Range of values : non-negative arbitrary floating-point number

    • Type : float

    • Required : yes

Inputs :

  • 1 : A tensor of type T and arbitrary shape. Required.

Outputs :

  • 1 : The result of element-wise Elu function applied to the input tensor. A tensor of type T and the same shape as input tensor.


  • T : arbitrary supported floating-point type.


<layer ... type="Elu">
    <data alpha="1.0"/>
        <port id="0">
        <port id="1">