/* F08KP_P0W_F C++ Header Example Program.
*
* Copyright 2024 Numerical Algorithms Group.
* Mark 30.0, 2024.
*/
#include <iostream>
#include <dco.hpp>
#include <nag.h>
#include <nagad.h>
#include <nagx04.h>
#include <stdio.h>
#include <string>
using namespace std;
int main()
{
int exit_status = 0;
nag::ad::handle_t ad_handle;
Integer ifail = 0;
NagError fail;
INIT_FAIL(fail);
cout << "F08KP_P0W_F C++ Header Example Program Results\n\n";
// Skip heading in data file
string mystr;
getline(cin, mystr);
// Read matrix dimensions
Integer m, n;
cin >> m;
cin >> n;
// Allocate arrays containing A and its factorized form, B
// and the solution X.
Integer lda = m, ldu = m, ldvt = n, lwork;
Complex *a = 0, *u = 0, *vt = 0, *work = 0, dummy[1];
double * s = 0, *rwork = 0;
Charlen lena = 1;
a = new Complex[m * n];
s = new double[m];
rwork = new double[5 * n];
u = new Complex[m * m];
vt = new Complex[n * n];
// Read the matrix A, register and copy
double dd, di;
for (int i = 0; i < m; i++)
{
for (int j = 0; j < n; j++)
{
cin >> dd >> di;
Integer k = i + j * m;
a[k].re = dd;
a[k].im = di;
}
}
// Use routine workspace query to get optimal workspace.
ifail = 0;
lwork = -1;
nag::ad::f08kp(ad_handle, "A", "A", m, n, a, lda, s, u, ldu, vt, ldvt, dummy,
lwork, rwork, ifail);
lwork = (Integer)dummy[0].re + 1;
work = new Complex[lwork];
// Compute the singular values and left and right singular vectors
// of A (A = U*S*(V**T), m < n)
nag::ad::f08kp(ad_handle, "A", "A", m, n, a, lda, s, u, ldu, vt, ldvt, work,
lwork, rwork, ifail);
// Print primal solution
cout.precision(4);
cout.width(12);
cout << " ";
cout << " Singular values:\n";
for (int i = 0; i < n; i++)
{
cout.width(11);
cout << s[i];
}
cout << "\n\n";
x04dac(Nag_ColMajor, Nag_GeneralMatrix, Nag_NonUnitDiag, m, m, u, m,
"Left singular vectors by column", 0, &fail);
cout << "\n";
x04dac(Nag_ColMajor, Nag_GeneralMatrix, Nag_NonUnitDiag, n, n, vt, n,
"Right singular vectors by row", 0, &fail);
delete[] a;
delete[] s;
delete[] u;
delete[] vt;
delete[] work;
delete[] rwork;
return exit_status;
}