Neural Network Toolbox

midpoint

Midpoint weight initialization function

Syntax

• W = midpoint(S,PR)
  

Description

midpoint is a weight initialization function that sets weight (row) vectors to the center of the input ranges.

midpoint(S,PR) takes two arguments,

• S -- Number of rows (neurons)

  PR -- R x 2 matrix of input value ranges = [Pmin Pmax]

and returns an S x R matrix with rows set to (Pmin+Pmax)'/2.

Examples

Here initial weight values are calculated for a 5 neuron layer with input elements ranging over [0 1] and [-2 2].

• W = midpoint(5,[0 1; -2 2])
  

Network Use

You can create a standard network that uses midpoint to initialize weights by calling newc.

To prepare the weights and the bias of layer i of a custom network to initialize with midpoint:

1. Set net.initFcn to 'initlay'. (net.initParam will automatically become initlay's default parameters.)
2. Set net.layers{i}.initFcn to 'initwb'.
3. Set each net.inputWeights{i,j}.initFcn to 'midpoint'. Set each net.layerWeights{i,j}.initFcn to 'midpoint';

To initialize the network call init.

See Also

• initwb, initlay, init
  

maxlinlr

minmax

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