📄 lmdif1.c
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/* lmdif1.f -- translated by f2c (version 20020621). You must link the resulting object file with the libraries: -lf2c -lm (in that order)*/#include "cminpack.h"/* Subroutine */ int lmdif1(minpack_func_mn fcn, void *p, int m, int n, double *x, double *fvec, double tol, int *iwa, double *wa, int lwa){ /* Initialized data */ const double factor = 100.; int mp5n, mode, nfev; double ftol, gtol, xtol; double epsfcn; int maxfev, nprint; int info;/* ********** *//* subroutine lmdif1 *//* the purpose of lmdif1 is to minimize the sum of the squares of *//* m nonlinear functions in n variables by a modification of the *//* levenberg-marquardt algorithm. this is done by using the more *//* general least-squares solver lmdif. the user must provide a *//* subroutine which calculates the functions. the jacobian is *//* then calculated by a forward-difference approximation. *//* the subroutine statement is *//* subroutine lmdif1(fcn,m,n,x,fvec,tol,info,iwa,wa,lwa) *//* where *//* fcn is the name of the user-supplied subroutine which *//* calculates the functions. fcn must be declared *//* in an external statement in the user calling *//* program, and should be written as follows. *//* subroutine fcn(m,n,x,fvec,iflag) *//* integer m,n,iflag *//* double precision x(n),fvec(m) *//* ---------- *//* calculate the functions at x and *//* return this vector in fvec. *//* ---------- *//* return *//* end *//* the value of iflag should not be changed by fcn unless *//* the user wants to terminate execution of lmdif1. *//* in this case set iflag to a negative integer. *//* m is a positive integer input variable set to the number *//* of functions. *//* n is a positive integer input variable set to the number *//* of variables. n must not exceed m. *//* x is an array of length n. on input x must contain *//* an initial estimate of the solution vector. on output x *//* contains the final estimate of the solution vector. *//* fvec is an output array of length m which contains *//* the functions evaluated at the output x. *//* tol is a nonnegative input variable. termination occurs *//* when the algorithm estimates either that the relative *//* error in the sum of squares is at most tol or that *//* the relative error between x and the solution is at *//* most tol. *//* info is an integer output variable. if the user has *//* terminated execution, info is set to the (negative) *//* value of iflag. see description of fcn. otherwise, *//* info is set as follows. *//* info = 0 improper input parameters. *//* info = 1 algorithm estimates that the relative error *//* in the sum of squares is at most tol. *//* info = 2 algorithm estimates that the relative error *//* between x and the solution is at most tol. *//* info = 3 conditions for info = 1 and info = 2 both hold. *//* info = 4 fvec is orthogonal to the columns of the *//* jacobian to machine precision. *//* info = 5 number of calls to fcn has reached or *//* exceeded 200*(n+1). *//* info = 6 tol is too small. no further reduction in *//* the sum of squares is possible. *//* info = 7 tol is too small. no further improvement in *//* the approximate solution x is possible. *//* iwa is an integer work array of length n. *//* wa is a work array of length lwa. *//* lwa is a positive integer input variable not less than *//* m*n+5*n+m. *//* subprograms called *//* user-supplied ...... fcn *//* minpack-supplied ... lmdif *//* argonne national laboratory. minpack project. march 1980. *//* burton s. garbow, kenneth e. hillstrom, jorge j. more *//* ********** */ /* Parameter adjustments */ --fvec; --iwa; --x; --wa; /* Function Body */ info = 0;/* check the input parameters for errors. */ if (n <= 0 || m < n || tol < 0. || lwa < m * n + n * 5 + m) { /* goto L10; */ return info; }/* call lmdif. */ maxfev = (n + 1) * 200; ftol = tol; xtol = tol; gtol = 0.; epsfcn = 0.; mode = 1; nprint = 0; mp5n = m + n * 5; info = lmdif(fcn, p, m, n, &x[1], &fvec[1], ftol, xtol, gtol, maxfev, epsfcn, &wa[1], mode, factor, nprint, &nfev, &wa[mp5n + 1], m, &iwa[1], &wa[n + 1], &wa[(n << 1) + 1], &wa[n * 3 + 1], &wa[(n << 2) + 1], &wa[n * 5 + 1]); if (info == 8) { info = 4; }/* L10: */ return info;/* last card of subroutine lmdif1. */} /* lmdif1_ */
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