Sigmoid activation function.

Namespace:  AForge.Neuro
Assembly:  AForge.Neuro (in AForge.Neuro.dll) Version: 2.2.5.0 (2.2.5.0)

Syntax

C#
[SerializableAttribute]
public class SigmoidFunction : IActivationFunction, 
	ICloneable

Remarks

The class represents sigmoid activation function with the next expression:

Copy 
               1
f(x) = ------------------
       1 + exp(-alpha * x)

          alpha * exp(-alpha * x )
f'(x) = ---------------------------- = alpha * f(x) * (1 - f(x))
          (1 + exp(-alpha * x))^2

Output range of the function: [0, 1].

Functions graph:

Inheritance Hierarchy

System..::.Object
  AForge.Neuro..::.SigmoidFunction

See Also