/* D01BD_T1W_F C++ Header Example Program.
*
* Copyright 2024 Numerical Algorithms Group.
* Mark 30.1, 2024.
*/
#include <dco.hpp>
#include <iostream>
#include <math.h>
#include <nag.h>
#include <nagad.h>
#include <nagx01.h>
#include <stdio.h>
using namespace std;
int main()
{
// Scalars
int exit_status = 0;
cout << "D01BD_T1W_F C++ Header Example Program Results\n\n";
// Skip first line of data file
string mystr;
getline(cin, mystr);
// Read problem parameters
double ar, br, epsabsr, epsrelr;
cin >> ar;
cin >> br;
cin >> epsabsr;
cin >> epsrelr;
nagad_t1w_w_rtype a, b, epsabs, epsrel;
a = ar;
b = br;
epsabs = epsabsr;
epsrel = epsrelr;
// Create AD configuration data object
Integer ifail = 0;
nag::ad::handle_t ad_handle;
nagad_t1w_w_rtype result, abserr, ruser[1];
Integer iuser[1];
ruser[0] = 10.0;
iuser[0] = 0;
auto f = [&](nag::ad::handle_t & ad_handle,
const nagad_t1w_w_rtype &x,
nagad_t1w_w_rtype & ret)
{
// dco/c++ used here to perform AD of the following
double pi = X01AAC;
nagad_t1w_w_rtype prx, x2, s;
x2 = x * x;
prx = pi * ruser[0];
prx = prx * x;
s = sin(prx);
ret = x2 * s;
iuser[0]++;
};
// Call the AD routine
// Increment variables to differentiate w.r.t.
double inc = 1.0;
dco::derivative(ruser[0]) = inc;
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) = " << ar << endl;
cout << " upper limit of integration (b) = " << br << endl;
cout << " absolute accuracy requested = " << epsabsr << endl;
cout << " relative accuracy requested = " << epsrelr << endl;
cout.setf(ios::scientific, ios::floatfield);
cout.precision(4);
if (ifail >= 0)
{
cout << "\n approximation to the integral : " << dco::value(result)
<< endl;
cout << " estimate of the absolute error : " << dco::value(abserr) << endl;
cout << " number of function evaluations : " << iuser[0] << endl;
}
cout << "\n Derivatives calculated: First order tangents\n";
cout << " Computational mode : algorithmic\n";
// Get derivatives
double dr = dco::derivative(result);
cout << "\n Derivative of solution w.r.t to ruser[0]:\n";
cout << " d/dr(x) = " << dr << endl;
return exit_status;
}