/* nag_hermitian_eigensystem (f02axc) Example Program.
*
* Copyright 2014 Numerical Algorithms Group.
*
* Mark 2, 1991.
* Mark 8 revised, 2004.
*/
#include <nag.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <nagf02.h>
#define A(I, J) a[(I) *tda + J]
#define V(I, J) v[(I) *tdv + J]
int main(void)
{
Complex *a = 0, *v = 0;
Integer exit_status = 0, i, j, n, tda, tdv;
NagError fail;
double *r = 0;
INIT_FAIL(fail);
printf(
"nag_hermitian_eigensystem (f02axc) Example Program Results\n");
scanf("%*[^\n]"); /* Skip heading in data file */
scanf("%ld", &n);
if (n >= 1)
{
if (!(r = NAG_ALLOC(n, double)) ||
!(a = NAG_ALLOC((n)*(n), Complex)) ||
!(v = NAG_ALLOC((n)*(n), Complex)))
{
printf("Allocation failure\n");
exit_status = -1;
goto END;
}
tda = n;
tdv = n;
}
else
{
printf("Invalid n.\n");
exit_status = 1;
return exit_status;
}
for (i = 0; i < n; i++)
for (j = 0; j < n; j++)
scanf(" ( %lf, %lf ) ", &A(i, j).re, &A(i, j).im);
/* nag_hermitian_eigensystem (f02axc).
* All eigenvalues and eigenvectors of complex Hermitian
* matrix
*/
nag_hermitian_eigensystem(n, a, tda, r, v, tdv, &fail);
if (fail.code != NE_NOERROR)
{
printf("Error from nag_hermitian_eigensystem (f02axc).\n%s\n",
fail.message);
exit_status = 1;
goto END;
}
printf("Eigenvalues\n");
for (i = 0; i < n; i++)
printf("%9.4f", r[i]);
printf("\nEigenvectors\n");
for (i = 0; i < n; i++)
for (j = 0; j < n; j++)
printf("(%7.3f %7.3f )%s", V(i, j).re, V(i, j).im,
(j%4 == 3 || j == n-1)?"\n":" ");
END:
NAG_FREE(r);
NAG_FREE(a);
NAG_FREE(v);
return exit_status;
}