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#include "v3p_netlib.h"
#include <stdio.h>
double f(double *x)
{
return (*x)/(1+(*x)*(*x));
}
void test_simpson_integral()
{
double a = 0;
double b = 1;
double res;
long n = 100;
v3p_netlib_simpru_(&f, &a, &b, &n, &res);
printf("simpson integral of x/(1+x^2) from 0 to 1 (%ld grids) is %2.10f\n", n, res);
}
void test_adapted_simpson_integral()
{
double a = 0;
double b = 1;
double res;
long n = 100;
double rmat[1111];
double tol = 1e-10;
double errbound;
long stat;
v3p_netlib_adaptquad_(&f, &a, &b, &tol, rmat, &res, &errbound, &n, &stat);
printf("adapted simpson integral (with tol=%g) of x/(1+x^2) from 0 to 1 (%ld grids) is %2.10f\n", tol, n, res);
printf("errbound is %f, state is %ld\n", errbound, stat);
}
void test_trapezod_integral()
{
double a = 0;
double b = 1;
double res;
long n = 500;
v3p_netlib_trapru_(&f, &a, &b, &n, &res);
printf("trapezod integral of x/(1+x^2) from 0 to 1 (%ld grids) is %f\n", n, res);
}
int main()
{
test_simpson_integral();
test_adapted_simpson_integral();
test_trapezod_integral();
return 0;
}
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