/*RM 4/1 gr. studentas DARIUS RAMANAUSKAS*/
	/*Si programa skirta diodo VACH koeficientu nustatymui*/
	/*Diodo VACH yra aprasoma formule, kurioje yra trys nezinomi koeficientai,*/
	/*kuriuos reikia optimizuoti konkreciam diodui. Keliuose VACH taskuose*/
	/*ismatuojame diodo itampas ir sroves.Optimizavimas vykdomas pagal*/
	/*kvadratine paklaida. Optimizavimo programa apskaiciuoja*/
	/*optimalius koeficientus ir juos istacius i VACH formule*/
	/* gauname optimalia diodo charakteristika ir galime geriau*/
	/* parinkti reikiama dioda.Programa dar gali buti tobulinama.Bet realiai*/
	/*reikejo parinkti tik kelis diodus, tai programos patobulinimui*/
	/*neliko laiko.Mano e-mail: dickas@yahoo.com*/
	# include "fi.h"
	# include <stdio.h>
	# include <stdlib.h>
//	# include <bios.h>
	# include <math.h>
	# define tasku_sk 4
int number_of_variables =tasku_sk;	
double fi (const double *x, int n)
	{
	int i;
	double y[tasku_sk], value[tasku_sk],Ic[tasku_sk],Vbe[tasku_sk];
	double norma;


	Vbe[0]=0.62,Vbe[1]=0.7,Vbe[2]=0.8,Vbe[3]=0.91;
	Ic[0]=0.0005,Ic[1]=0.008,Ic[2]=0.05,Ic[3]=0.2;


	for(i=0;i<tasku_sk;i++)
				{
				y[i]=0.025*x[0]*log(Ic[i]/x[1])+Ic[i]*x[2];
				}

	norma=0;
	for(i=0;i<tasku_sk;i++)
		{value[i]=(y[i]-Vbe[i])*(y[i]-Vbe[i]);
                 norma=norma+value[i];}
		 return(norma);
	}
	/*==============Definition of constraints==============*/

	void constr (const double *x, int n, double *g, int ng)
	 {
	   /*
             ng > 0 - calculates all constaints
	     ng < 0  - calculates only constraint with number (-ng)
	   */
        double x1 = x [0];
        double x2 = x [1];
        double x3 = x1 * x1;
        double x4 = x2 * x2;

        if (ng > 0) {
		   g [0] = 25. - x3 - x4;
		   g [1] = 10. * x1 - x3 + 10. * x2 - x4 - 34.;
		   g [2] = x1;
		   g [3] = x2;
           	   }
		 else
		{
                 ng = -ng;
                 switch (ng) {
                 case 1:
	      		       g [0] = 25. - x3 - x4;
			       break;
                 case 2:
		               g [1] = 10. * x1 - x3 + 10. * x2 - x4 - 34.;
			       break;
                 case 3:
			       g [2] = x1;
			       break;
                 case 4:
			       g [3] = x2;
			       break;
                             }
                  }
         }