Daniel@0: function net = rbfsetfw(net, scale)
Daniel@0: %RBFSETFW Set basis function widths of RBF.
Daniel@0: %
Daniel@0: %	Description
Daniel@0: %	NET = RBFSETFW(NET, SCALE) sets the widths of the basis functions of
Daniel@0: %	the RBF network NET. If Gaussian basis functions are used, then the
Daniel@0: %	variances are set to the largest squared distance between centres if
Daniel@0: %	SCALE is non-positive and SCALE times the mean distance of each
Daniel@0: %	centre to its nearest neighbour if SCALE is positive.  Non-Gaussian
Daniel@0: %	basis functions do not have a width.
Daniel@0: %
Daniel@0: %	See also
Daniel@0: %	RBFTRAIN, RBFSETBF, GMMEM
Daniel@0: %
Daniel@0: 
Daniel@0: %	Copyright (c) Ian T Nabney (1996-2001)
Daniel@0: 
Daniel@0: % Set the variances to be the largest squared distance between centres
Daniel@0: if strcmp(net.actfn, 'gaussian')
Daniel@0:    cdist = dist2(net.c, net.c);
Daniel@0:    if scale > 0.0
Daniel@0:       % Set variance of basis to be scale times average
Daniel@0:       % distance to nearest neighbour
Daniel@0:       cdist = cdist + realmax*eye(net.nhidden);
Daniel@0:       widths = scale*mean(min(cdist));
Daniel@0:    else
Daniel@0:       widths = max(max(cdist));
Daniel@0:    end
Daniel@0:    net.wi = widths * ones(size(net.wi));
Daniel@0: end