/* nag_sparse_sym_sort (f11zbc) Example Program.
*
* Copyright 2014 Numerical Algorithms Group.
*
* Mark 5, 1998.
*
*/

#include <nag.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <nagf11.h>

int main(void)
{
double              *a = 0;
Integer             *icol = 0;
Integer             *irow = 0, *istr = 0;
Integer             exit_status = 0, i, n, nnz;
Nag_SparseSym_Zeros zero;
Nag_SparseSym_Dups  dup;
NagError            fail;

INIT_FAIL(fail);

printf("nag_sparse_sym_sort (f11zbc) Example Program Results\n");

/* Skip heading in data file */
scanf(" %*[^\n]");

/* Read order of matrix and number of non-zero entries */
scanf("%ld%*[^\n]", &n);
scanf("%ld%*[^\n]", &nnz);

/* Allocate memory */
istr = NAG_ALLOC(n+1, Integer);
a = NAG_ALLOC(nnz, double);
irow = NAG_ALLOC(nnz, Integer);
icol = NAG_ALLOC(nnz, Integer);

if (!istr || !irow || !icol || !a)
{
printf("Allocation failure\n");
exit_status = -1;
goto END;
}

/* Read and output the original non-zero elements */
for (i = 1; i <= nnz; ++i)
scanf("%lf%ld%ld%*[^\n]", &a[i-1], &irow[i-1], &icol[i-1]);
printf(" Original elements \n");
printf(" nnz =  %6ld\n", nnz);
for (i = 1; i <= nnz; ++i)
printf(" %8ld%16.4e%8ld%8ld\n", i, a[i-1],
irow[i-1], icol[i-1]);

/* Reorder, sum duplicates and remove zeros */
dup = Nag_SparseSym_SumDups;
zero = Nag_SparseSym_RemoveZeros;

/* nag_sparse_sym_sort (f11zbc).
* Sparse sort (symmetric)
*/
nag_sparse_sym_sort(n, &nnz, a, irow, icol, dup, zero, istr, &fail);
if (fail.code != NE_NOERROR)
{
printf("Error from nag_sparse_sym_sort (f11zbc).\n%s\n",
fail.message);
exit_status = 1;
goto END;
}

/* Output results */
printf(" Reordered elements \n");
printf(" nnz = %4ld\n", nnz);

for (i = 1; i <= nnz; ++i)
printf(" %8ld%16.4e%8ld%8ld\n", i, a[i-1],
irow[i-1], icol[i-1]);

END:
NAG_FREE(istr);
NAG_FREE(irow);
NAG_FREE(icol);
NAG_FREE(a);
return exit_status;
}