Neural Network Toolbox

dtansig

Hyperbolic tangent sigmoid transfer derivative function

Syntax

dA_dN = dtansig(N,A)

Description

dtansig is the derivative function for tansig.

dtansig(N,A) takes two arguments,

• N -- S x Q net input

  A -- S x Q output

and returns the S x Q derivative dA/dN.

Examples

Here we define the net input N for a layer of 3 tansig neurons.

• N = [0.1; 0.8; -0.7];
  

We calculate the layer's output A with tansig and then the derivative of A with respect to N.

• A = tansig(N)
  dA_dN = dtansig(N,A)
  

Algorithm

The derivative of tansig is calculated as follows:

• d = 1-a^2
  

See Also

tansig, logsig, dlogsig

dsse

dtribas

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