/* D01FC_P0W_F C++ Header Example Program.
 *
 * Copyright 2019 Numerical Algorithms Group.
 * Mark 27, 2019.
 */

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

extern "C"
{
  static void NAG_CALL f(void* &ad_handle,
                             const Integer& ndim,
                             const double z[],
                             double& fz,
                             Integer iuser[],
                             double ruser[]);
}

int main(void)
{
  // Scalars
  int     exit_status = 0;
  Integer ndim = 4, maxpts = 4000, lenwrk = 100;

  cout << "D01FC_P0W_F C++ Header Example Program Results\n\n";

  // Allocate memory
  double *a = 0, *b = 0, *work = 0;

  a = new double [ndim];
  b = new double [ndim];
  work = new double [lenwrk];

  // Initialize variables
  for (int i = 0; i < ndim; i++) {
    a[i] = 0.0;
    b[i] = 1.0;
  }
  Integer minpts = 0;
  double  eps = 0.0001;
  double  ruser[3];
  ruser[0] = 4.0;
  ruser[1] = 2.0;
  ruser[2] = 1.0;

  // Call the passive routine
  void    *ad_handle = 0;
  Integer ifail = 0;
  double  finval, acc;
  Integer iuser[1];
  d01fc_p0w_f_(ad_handle,ndim,a,b,minpts,maxpts,f,eps,acc,lenwrk,
               work,finval,iuser,ruser,ifail);

  cout.setf(ios::scientific,ios::floatfield);
  cout.setf(ios::right);
  cout.precision(4);
  cout << "\n Solution, x = ";
  cout.width(12); cout << finval << endl;

  delete [] a;
  delete [] b;
  delete [] work;
  return exit_status;
}

static void NAG_CALL f(void* &ad_handle,
                           const Integer& ndim,
                           const double z[],
                           double& fz,
                           Integer iuser[],
                           double ruser[])
{
  double f1, f2, f3;

  f1 = ruser[0]*z[0]*z[2]*z[2];
  f2 = ruser[1]*z[0]*z[2];
  f2 = exp(f2);
  f3 = ruser[2] + z[1] + z[3];
  f3 = f3*f3;
  fz = f1*f2/f3;

  return;
}