deltalin.m

模式识别 MATLAB 的工具箱,比较实用,包括SVM,ICA,PCA,NN等等模式识别算法.

function d = deltalin(a,d,w)
%DELTALIN Delta function for PURELIN neurons.
%	
%	DELATLIN(A)
%	  A - S1xQ matrix of output vectors.
%	Returns the S1xQ matrix of derivatives of the output vectors
%	  with respect to the net input of the PURELIN transfer function.
%	
%	DELTALIN(A,E)
%	  E - S1xQ matrix of associated errors
%	Returns an S1xQ matrix of derivatives of error for an output layer.
%	
%	DELTALIN(A,D,W)
%	  D - S2xQ matrix of next layer delta vectors
%	  W - S2xS1 weight matrix between layers.
%	Returns an S1xQ matrix of derivatives of error for a hidden layer.
%	
% See also NNTRANS, BACKPROP, PURELIN.

% Mark Beale, 1-31-92
% Revised 12-15-93, MB
% Copyright (c) 1992-94 by the MathWorks, Inc.
% $Revision: 1.1 $  $Date: 1994/01/11 16:24:02 $

if nargin == 1
  d = ones(size(a));
elseif nargin == 2
  d = d;
else
  d = w'*d;
end