Mercurial > hg > camir-aes2014
diff toolboxes/FullBNT-1.0.7/netlab3.3/rbffwd.m @ 0:e9a9cd732c1e tip
first hg version after svn
author | wolffd |
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date | Tue, 10 Feb 2015 15:05:51 +0000 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/toolboxes/FullBNT-1.0.7/netlab3.3/rbffwd.m Tue Feb 10 15:05:51 2015 +0000 @@ -0,0 +1,55 @@ +function [a, z, n2] = rbffwd(net, x) +%RBFFWD Forward propagation through RBF network with linear outputs. +% +% Description +% A = RBFFWD(NET, X) takes a network data structure NET and a matrix X +% of input vectors and forward propagates the inputs through the +% network to generate a matrix A of output vectors. Each row of X +% corresponds to one input vector and each row of A contains the +% corresponding output vector. The activation function that is used is +% determined by NET.ACTFN. +% +% [A, Z, N2] = RBFFWD(NET, X) also generates a matrix Z of the hidden +% unit activations where each row corresponds to one pattern. These +% hidden unit activations represent the design matrix for the RBF. The +% matrix N2 is the squared distances between each basis function centre +% and each pattern in which each row corresponds to a data point. +% +% See also +% RBF, RBFERR, RBFGRAD, RBFPAK, RBFTRAIN, RBFUNPAK +% + +% Copyright (c) Ian T Nabney (1996-2001) + +% Check arguments for consistency +errstring = consist(net, 'rbf', x); +if ~isempty(errstring); + error(errstring); +end + +[ndata, data_dim] = size(x); + +% Calculate squared norm matrix, of dimension (ndata, ncentres) +n2 = dist2(x, net.c); + +% Switch on activation function type +switch net.actfn + + case 'gaussian' % Gaussian + % Calculate width factors: net.wi contains squared widths + wi2 = ones(ndata, 1) * (2 .* net.wi); + + % Now compute the activations + z = exp(-(n2./wi2)); + + case 'tps' % Thin plate spline + z = n2.*log(n2+(n2==0)); + + case 'r4logr' % r^4 log r + z = n2.*n2.*log(n2+(n2==0)); + + otherwise + error('Unknown activation function in rbffwd') +end + +a = z*net.w2 + ones(ndata, 1)*net.b2; \ No newline at end of file