logistic.c

/* LOGISTIC EQUATION */

#include <stdio.h>
#include <math.h>

int main()
{
    FILE   *fp;
    int    i;
    int    k;
    double r =  2.5;
    double xp[20000];
    double x0[20000];
    double xmin[50];
    double xmax[50];
    fp = fopen("lynopinof.txt", "w");

    /* Initial condition */
    xp[0] = 0.501;
    x0[0] = 0.5;
    i     = 0;
    k     = 1;

    /* Program -------------------------------------- */
    while ( r<= 3) {
        while (k< 20) {
            for (i=0; i< 1500; i++) {
                x0[i+1] = r * x0[i] * (1.0 - x0[i]);     
                xp[i+1] = r * xp[i] * (1.0 - xp[i]);
                if (i> 500) {
                    if (fabs(xp[i] - x0[i]) > fabs(xp[i-1] - x0[i-1]) && fabs(xp[i-1] - xp[i-1]) < fabs(xp[i-2] - xp[i-2])) {
                        xmin[k] = fabs(xp[i-1] - x0[i-1]);
                        while (fabs(xp[i] - x0[i]) > fabs(xp[i-1] - x0[i-1])) {
							i++;
                        }
                        xmax[k] = fabs(xp[i-1] - x0[i-1]);
                        fprintf(fp,"%6.31f %6.3lf %6.3lf %6.3lf\n", r, k, xmin[k], xmax[k]);
                        
                    }
                    
                }
            } 
            k++;
        }
        r=r+.02;
    }

    fclose(fp);
}