gradchek(w, func, grad) [gradient, delta] = gradchek(w, func, grad) gradchek(w, func, grad, p1, p2, ...)
gradchek(w, func, grad) checks how accurate the gradient
grad of a function func is at a parameter vector x.
A central
difference formula with step size 1.0e-6 is used, and the results
for both gradient function and finite difference approximation are
printed.
The optional return value gradient is the gradient calculated
using the function grad and the return value delta is the
difference between the functional and finite difference methods of
calculating the graident.
gradchek(x, func, grad, p1, p2, ...) allows additional arguments
to be passed to func and grad.
conjgrad, graddesc, hmc, olgd, quasinew, scgCopyright (c) Ian T Nabney (1996-9)