Daniel@0: function mags = gtmmag(net, latent_data)
Daniel@0: %GTMMAG	Magnification factors for a GTM
Daniel@0: %
Daniel@0: %	Description
Daniel@0: %	 MAGS = GTMMAG(NET, LATENTDATA) takes a GTM structure NET, and
Daniel@0: %	computes the magnification factors for each point the latent space
Daniel@0: %	contained in LATENTDATA.
Daniel@0: %
Daniel@0: %	See also
Daniel@0: %	GTM, GTMPOST, GTMLMEAN
Daniel@0: %
Daniel@0: 
Daniel@0: %	Copyright (c) Ian T Nabney (1996-2001)
Daniel@0: 
Daniel@0: errstring = consist(net, 'gtm');
Daniel@0: if ~isempty(errstring)
Daniel@0:   error(errstring);
Daniel@0: end
Daniel@0: 
Daniel@0: Jacs = rbfjacob(net.rbfnet, latent_data);
Daniel@0: nlatent = size(latent_data, 1);
Daniel@0: mags = zeros(nlatent, 1);
Daniel@0: temp = zeros(net.rbfnet.nin, net.rbfnet.nout);
Daniel@0: for m = 1:nlatent
Daniel@0:   temp = squeeze(Jacs(m, :, :));  % Turn into a 2d matrix
Daniel@0:   mags(m) = sqrt(det(temp*temp'));
Daniel@0: end