/* D01BD_P0W_F C++ Header Example Program.
*
* Copyright 2023 Numerical Algorithms Group.
* Mark 29.2, 2023.
*/
#include <iostream>
#include <math.h>
#include <nag.h>
#include <nagad.h>
#include <nagx01.h>
#include <stdio.h>
#include <string>
using namespace std;
int main()
{
// Scalars
int exit_status = 0;
cout << "D01BD_P0W_F C++ Header Example Program Results\n\n";
// Skip first line of data file
string mystr;
getline(cin, mystr);
// Read problem parameters
double a, b, epsabs, epsrel;
cin >> a;
cin >> b;
cin >> epsabs;
cin >> epsrel;
nag::ad::handle_t ad_handle;
double result, abserr, ruser[1];
Integer iuser[1];
ruser[0] = 10.0;
iuser[0] = 0;
auto f = [&](nag::ad::handle_t & ad_handle,
const double &x,
double & ret)
{
// dco/c++ used here to perform AD of the following
double pi = X01AAC;
double prx, x2, s;
x2 = x * x;
prx = pi * ruser[0];
prx = prx * x;
s = sin(prx);
ret = x2 * s;
iuser[0]++;
};
// Call the passive routine
Integer ifail = 0;
nag::ad::d01bd(ad_handle, f, a, b, epsabs, epsrel, result, abserr, ifail);
// Print inputs and primal outputs.
cout << "\n lower limit of integration (a) = " << a << endl;
cout << " upper limit of integration (b) = " << b << endl;
cout << " absolute accuracy requested = " << epsabs << endl;
cout << " relative accuracy requested = " << epsrel << endl;
cout.setf(ios::scientific, ios::floatfield);
cout.precision(4);
if (ifail >= 0)
{
cout << "\n approximation to the integral : " << result << endl;
cout << " estimate of the absolute error : " << abserr << endl;
cout << " number of function evaluations : " << iuser[0] << endl;
}
return exit_status;
}