NAG Library Manual, Mark 30
Interfaces:  FL   CL   CPP   AD 

NAG AD Library Introduction
Example description
/* F11XE_P0W_F C++ Header Example Program.
 *
 * Copyright 2024 Numerical Algorithms Group.
 * Mark 30.0, 2024.
 */
#include <dco.hpp>
#include <iostream>
#include <nag.h>
#include <nagad.h>
#include <nagx04.h>
#include <stdio.h>
using namespace std;

int main()
{
  int               exit_status = 0;
  nag::ad::handle_t ad_handle;
  Integer           ifail = 0;

  cout << "F11XE_P0W_F C++ Header Example Program Results\n\n";
  // Skip heading in data file
  string mystr;
  getline(cin, mystr);

  // Read order of matrix and number of nonzero entries
  Integer n, nnz;
  cin >> n;
  cin >> nnz;

  double * a = 0, *x = 0, *y = 0;
  Integer *icol = 0, *irow = 0;

  a    = new double[nnz];
  x    = new double[n];
  y    = new double[n];
  icol = new Integer[nnz];
  irow = new Integer[nnz];

  // Read the matrix A
  for (int i = 0; i < nnz; i++)
  {
    cin >> a[i] >> irow[i] >> icol[i];
  }

  // Read the vector x
  for (int i = 0; i < n; i++)
  {
    cin >> x[i];
  }

  // Calculate matrix-vector product
  ifail = 0;
  nag::ad::f11xe(ad_handle, n, nnz, a, irow, icol, "C", x, y, ifail);

  // Output results
  cout.setf(ios::scientific, ios::floatfield);
  cout.precision(4);
  cout << "  Matrix-vector product" << endl;
  for (int i = 0; i < n; ++i)
  {
    cout.width(12);
    cout << y[i] << endl;
  }

  delete[] a;
  delete[] x;
  delete[] y;
  delete[] icol;
  delete[] irow;

  return exit_status;
}