/*
 * This example demonstrate how to call MINUIT from C.
 *
 * For question/problems contact: Heplib.Support@cern.ch
 *
 */

#include <math.h>
#include <string.h>
#include <cfortran.h>

/*  Fortran has the following call:
 *     Subroutine FCN(Npar,Grad,Fval,Xval,Iflag,Futil)
 *    Implicit Double Precision (a-h,o-z)
 *
 *    Dimension Xval(*), Grad(*)
 * 
 */
void        fcn(int npar, double grad[3], double * fcnval,
                double xval[2],int iflag, void (*Dummy)());

FCALLSCSUB6(fcn,FCN,fcn,INT,DOUBLEV,PDOUBLE,DOUBLEV,INT,ROUTINE)

void fcn(int npar, double grad[3], double * fcnval,
           double xval[2],int iflag, void (*Dummy)())
{
      double Xc=1.11,Yc=3.14;
/* 
 *  demo FCN 
 *  Gunter Folger, May 95
 */

	switch(iflag) {
	  case 1:
/*
 *      Initialaise.
 */
		printf(" fcn_c called to initialise\n");
		break;
	  case 2:		
/*
 *        derivatives...
 */
		break;

	  default:
		*fcnval = pow(xval[0]-Xc,2.) + pow((xval[1]-Yc),3.)*xval[1];
		break;
	}      
}