Mercurial > hg > camir-aes2014
annotate toolboxes/FullBNT-1.0.7/netlab3.3/mlpinit.m @ 0:e9a9cd732c1e tip
first hg version after svn
author | wolffd |
---|---|
date | Tue, 10 Feb 2015 15:05:51 +0000 |
parents | |
children |
rev | line source |
---|---|
wolffd@0 | 1 function net = mlpinit(net, prior) |
wolffd@0 | 2 %MLPINIT Initialise the weights in a 2-layer feedforward network. |
wolffd@0 | 3 % |
wolffd@0 | 4 % Description |
wolffd@0 | 5 % |
wolffd@0 | 6 % NET = MLPINIT(NET, PRIOR) takes a 2-layer feedforward network NET and |
wolffd@0 | 7 % sets the weights and biases by sampling from a Gaussian distribution. |
wolffd@0 | 8 % If PRIOR is a scalar, then all of the parameters (weights and biases) |
wolffd@0 | 9 % are sampled from a single isotropic Gaussian with inverse variance |
wolffd@0 | 10 % equal to PRIOR. If PRIOR is a data structure of the kind generated by |
wolffd@0 | 11 % MLPPRIOR, then the parameters are sampled from multiple Gaussians |
wolffd@0 | 12 % according to their groupings (defined by the INDEX field) with |
wolffd@0 | 13 % corresponding variances (defined by the ALPHA field). |
wolffd@0 | 14 % |
wolffd@0 | 15 % See also |
wolffd@0 | 16 % MLP, MLPPRIOR, MLPPAK, MLPUNPAK |
wolffd@0 | 17 % |
wolffd@0 | 18 |
wolffd@0 | 19 % Copyright (c) Ian T Nabney (1996-2001) |
wolffd@0 | 20 |
wolffd@0 | 21 if isstruct(prior) |
wolffd@0 | 22 sig = 1./sqrt(prior.index*prior.alpha); |
wolffd@0 | 23 w = sig'.*randn(1, net.nwts); |
wolffd@0 | 24 elseif size(prior) == [1 1] |
wolffd@0 | 25 w = randn(1, net.nwts).*sqrt(1/prior); |
wolffd@0 | 26 else |
wolffd@0 | 27 error('prior must be a scalar or a structure'); |
wolffd@0 | 28 end |
wolffd@0 | 29 |
wolffd@0 | 30 net = mlpunpak(net, w); |
wolffd@0 | 31 |