#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#define NUM_POINTS 100
#define NUM_COMMANDS 2

int main()
{
    char* commandsForGnuplot[] = {"set title \"EXEMPLE\"", "plot 'data.temp'"};
	double xvals[NUM_POINTS];
    double yvals[NUM_POINTS];
    FILE * temp = fopen("data.temp", "w");
    FILE * gnuplotPipe = popen ("gnuplot -persistent", "w");
    int i;
    
    for (i=0; i < NUM_POINTS; i++)
    {
		xvals[i]= i*3,1415/50;
		yvals[i]= cos(xvals[i]);
		fprintf(temp, "%lf %lf \n", xvals[i], yvals[i]);
    }

    for (i=0; i < NUM_COMMANDS; i++)
    {
    fprintf(gnuplotPipe, "%s \n", commandsForGnuplot[i]);
    }
    return 0;
}