should create a bifurcation diagram...but you know doesnt

logistic

{
  FILE    *fp ;
  int     i ;
  double   r =  2.5 ;
  double   x[20000] ;

   fp = fopen("logisticmap2.txt","w") ;

/* Initial condition */

x[0] = 0.5 ;
i    = 0 ;

/* Program -------------------------------------- */
while ( r<= 4)
	{
	for (i=0; i< 1500; i++)
		{
		x[i+1] = r * x[i] * (1.0 - x[i]) ;	 
		if (i> 500) 
			{
			fprintf(fp,"%4d %6.3lf %6.3lf\n", r, x[i]);
			}
		} 
	r=r+.02;
	}

   fclose(fp) ;
}