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

double f1(
double t)
{
   double v;

   v = sin(t);
   return(v);
}


/**/
/* This function attempts to find a zero of a function */
/* using the bisection method                          */

int bisect(
double (*f)(double),    // external function whose zero we seek
double *minval,         // minimum of search range
double *maxval,         // maximum of search range
double epsilon)         // tolerance
{
   double f0;           // value at intvl start
   double f1;           // value at intvl end
   double ft;           // test value;
   double midval;       // point where secant has 0 value
   int    count = 0;


   ------------------------


/* printf("bsrch  val = %8.5lf %8.5lf %5d \n",
                  *minval, f0, count);            */
   return(count);
}

int main()
{
   int code;
   double min;
   double max;

   min = 0.5;
   max = 2.0;

   code = bisect(f1, &min, &max, 1.0e-10);
   printf("code = %5d min = %16.6le f(min) = %16.6le \n",
             code, min, f1(min));

   min = -1.5;
   max = 2.0;

   code = bisect(f1, &min, &max, 1.0e-10);
   printf("code = %5d min = %16.6le f(min) = %16.6le \n",
             code, min, f1(min));

   min = 0.5;
   max = 5.0;

   code = bisect(f1, &min, &max, 1.0e-10);
   printf("code = %5d min = %16.6le f(min) = %16.6le \n",
             code, min, f1(min));
}