54 lines
656 B
C
54 lines
656 B
C
#include "solve.h"
|
|
|
|
#include <math.h>
|
|
#include <float.h>
|
|
|
|
int t8_solve (
|
|
double (*f) (double),
|
|
double a, double b,
|
|
double eps, int m, double *res
|
|
) {
|
|
int it = 1;
|
|
double h = a - b;
|
|
double x_l = 0, y_l = 0, x = a, y = f(a);
|
|
|
|
if (fabs(b - a) < DBL_EPSILON)
|
|
{
|
|
*res = a;
|
|
return 1;
|
|
}
|
|
|
|
while (it <= m)
|
|
{
|
|
h *= -0.1;
|
|
|
|
while (1)
|
|
{
|
|
it++;
|
|
|
|
if (it > m)
|
|
return -1;
|
|
|
|
x_l = x;
|
|
y_l = y;
|
|
|
|
x += h;
|
|
y = f(x);
|
|
if ((y_l - y) > DBL_EPSILON)
|
|
break;
|
|
|
|
if ((a - x) > DBL_EPSILON || (x - b) > DBL_EPSILON) {
|
|
*res = x_l;
|
|
return it;
|
|
}
|
|
|
|
}
|
|
|
|
if ((y_l - y) < eps) {
|
|
*res = x_l;
|
|
return it;
|
|
}
|
|
}
|
|
|
|
return -1;
|
|
}
|