FORTRAN IV Program For Nonlinear Estimation

Abstract

NONLIN is a FORTRAN IV computer program for estimating parameters in algebraic nonlinear simultaneous equations. The program is designed for problems in which the number of observations equals or exceeds the number of parameters to be estimated. Starting from initial estimates, a modified Gauss-Newton procedure is used to obtain an improved set of parameter values. The process is continued until a set of best estimates has been obtained. A number of options in the program offer wide flexibility in handling a variety of nonlinear problems. Numerical examples are given for dissecting a bimodal distribution into normal components and estimating the porosity in vuggy carbonates.