fderiv3m

Overview

subroutine fderiv.f (non-analytical)

source
Bevington, page 242.

purpose
evaluate derivatives of function for least-squares search
for arbitrary function given by functn

usage
call fderiv (x, i, a, deltaa, nterms, deriv)

description of parameters
x - array of data points for independent variable
i - index of data points
a - array of parameters
deltaa - array of parameter increments
nterms - number of parameters
deriv - derivatives of function

subroutines and function subprograms required
functn (x, i, a)
evaluates the fitting function for the ith term