h = neterr(w, net, x, t) [h, varargout] = neterr(w, net, x, t, varargin)
h = nethess(w, net, x, t)
takes a weight vector w
and a network
data structure net
, together with the matrix x
of input
vectors and the matrix t
of target vectors, and returns the
value of the Hessian evaluated at w
.
[e, varargout] = nethess(w, net, x, t, varargin)
also returns any additional
return values from the network Hessian function, and passes additional arguments
to that function.
In evidence
, this function is called once to compute the
data contribution to the Hessian
[h, dh] = nethess(w, net, x, t, dh);and again to update the Hessian for new values of the hyper-parameters
h = nethess(w, net, x, t, dh);
neterr
, netgrad
, netopt
Copyright (c) Ian T Nabney (1996-9)