NAG Library Manual, Mark 27.2
Interfaces:  FL   CL   CPP   AD 

NAG AD Library Introduction
Example description
/* F01FJ_P0W_F C++ Header Example Program.
 *
 * Copyright 2021 Numerical Algorithms Group.
 * Mark 27.2, 2021.
 */

#include <iostream>
#include <nag.h>
#include <nagad.h>
#include <nagx04.h>
#include <stdio.h>
#include <string>
using namespace std;

int main(void)
{
  int     exit_status = 0;
  void *  ad_handle   = 0;
  Integer ifail       = 0;

  cout << "F01FJ_P0W_F C++ Header Example Program Results\n\n";
  // Skip heading in data file
  string mystr;
  getline(cin, mystr);

  // Read problem size and number of right-hand-sides
  Integer n;
  cin >> n;

  // Allocate arrays containing A and its factorized form, B
  // and the solution X.
  Complex *a = 0;
  a          = new Complex[n * n];

  // Read the matrix A, register and copy
  double dr, di;
  for (int i = 0; i < n; ++i)
    {
      for (int j = 0; j < n; ++j)
        {
          cin >> dr >> di;
          Integer k = i + j * n;
          a[k].re   = dr;
          a[k].im   = di;
        }
    }

  // Find log(A)
  ifail = 0;
  nag::ad::f01fj(ad_handle, n, a, n, ifail);

  // Print log(A)
  cout << endl;
  NagError fail;
  INIT_FAIL(fail);
  x04dac(Nag_ColMajor, Nag_GeneralMatrix, Nag_NonUnitDiag, n, n, a, n,
         "  Log(A)", 0, &fail);

  delete[] a;

  return exit_status;
}