/* D01PA_P0W_F C++ Header Example Program.
 *
 * Copyright 2021 Numerical Algorithms Group.
 * Mark 27.2, 2021.
 */

#include <iostream>
#include <math.h>
#include <nag.h>
#include <nagad.h>
#include <stdio.h>
using namespace std;

extern "C"
{
  static void NAG_CALL functn(void *&        ad_handle,
                              const Integer &ndim,
                              const double   x[],
                              double &       ret,
                              Integer        iuser[],
                              double         ruser[]);
}

int main(void)
{
  // Scalars
  int     exit_status = 0;
  Integer mxord = 5, ndim = 3, sdvert = 8, ldvert = 4;

  cout << "D01PA_P0W_F C++ Header Example Program Results\n\n";

  // Allocate memory
  double *finvls = 0, *vert = 0, *vert_in = 0;
  finvls = new double[mxord];
  vert   = new double[ldvert * sdvert];

  for (int i = 0; i < ndim * ldvert; i++)
    {
      vert[i] = 0.0;
    }
  for (int i = 1; i < ndim * ldvert; i = i + ldvert + 1)
    {
      vert[i] = 1.0;
    }

  void *ad_handle = 0;

  cout << "\n Maxord   Estimated      Estimated         Integrand\n";
  cout << "           value         accuracy        evaluations\n";
  cout.setf(ios::scientific, ios::floatfield);
  cout.precision(4);
  Integer minord = 0, nevals = 1;
  for (Integer maxord = 1; maxord <= mxord; maxord++)
    {

      // Call the passive routine
      double  esterr, ruser[1];
      Integer iuser[1];
      Integer ifail = 0;

      nag::ad::d01pa(ad_handle, ndim, vert, ldvert, sdvert, functn, minord,
                     maxord, finvls, esterr, -1, iuser, -1, ruser, ifail);
      double finv_r = finvls[maxord - 1];
      cout.width(5);
      cout << maxord;
      cout.width(15);
      cout << finv_r;
      cout.width(15);
      cout << esterr;
      cout.width(12);
      cout << nevals << endl;

      nevals = (nevals * (maxord + ndim + 1)) / maxord;
    }

  cout.setf(ios::right);
  cout.precision(4);
  cout << "\n Solution, I = ";
  double ans_value = finvls[mxord - 1];
  cout.width(12);
  cout << ans_value << endl;

  delete[] finvls;
  delete[] vert;
  return exit_status;
}
static void NAG_CALL functn(void *&        ad_handle,
                            const Integer &ndim,
                            const double   x[],
                            double &       ret,
                            Integer        iuser[],
                            double         ruser[])
{
  double tmp1;
  tmp1 = x[0] + x[1] + x[2];
  ret  = exp(tmp1) * cos(tmp1);
  return;
}