/* F11JC_P0W_F C++ Header Example Program.
*
* Copyright 2024 Numerical Algorithms Group.
* Mark 30.1, 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 << "F11JC_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;
Integer la = 3 * nnz;
Integer liwork = 2 * la + 7 * n + 1;
Integer lwork = 6 * n + 120;
double * a = 0, *x = 0, *y = 0, *work = 0;
Integer *icol = 0, *ipiv = 0, *irow = 0, *istr = 0, *iwork = 0;
a = new double[la];
x = new double[n];
y = new double[n];
work = new double[lwork];
icol = new Integer[la];
ipiv = new Integer[n];
irow = new Integer[la];
istr = new Integer[n + 1];
iwork = new Integer[liwork];
double dtol, dscale, tol;
Integer lfill, maxitn;
cin >> lfill >> dtol;
cin >> dscale;
cin >> tol >> maxitn;
// Read the matrix A
for (int i = 0; i < nnz; i++)
{
cin >> a[i] >> irow[i] >> icol[i];
}
// Read the vector y
for (int i = 0; i < n; i++)
{
cin >> y[i];
}
// Read initial vector x
for (int i = 0; i < n; i++)
{
cin >> x[i];
}
// Calculate incomplete Cholesky factorization
Integer nnzc, npivm;
ifail = 0;
nag::ad::f11ja(ad_handle, n, nnz, a, la, irow, icol, lfill, dtol, "N", dscale,
"M", ipiv, istr, nnzc, npivm, iwork, liwork, ifail);
// Solve Ax = y
double rnorm;
Integer itn;
ifail = 0;
nag::ad::f11jc(ad_handle, "CG", n, nnz, a, la, irow, icol, ipiv, istr, y, tol,
maxitn, x, rnorm, itn, work, lwork, ifail);
// Output results
cout << " Converged in " << itn << " iterations" << endl;
cout << " Final residual norm = " << rnorm << endl;
cout.setf(ios::scientific, ios::floatfield);
cout.precision(4);
cout << endl;
cout << " Solution vector" << endl;
for (int i = 0; i < n; ++i)
{
cout.width(12);
cout << x[i] << endl;
}
delete[] a;
delete[] x;
delete[] y;
delete[] work;
delete[] icol;
delete[] ipiv;
delete[] irow;
delete[] istr;
delete[] iwork;
return exit_status;
}