/* nag_sparse_nsym_sort (f11zac) Example Program.
 *
 * Copyright 2014 Numerical Algorithms Group.
 *
 * Mark 5, 1998.
 *
 */

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

int main(void)
{
  double               *a = 0, anorm = 0.0;
  Integer              *icol = 0;
  Integer              *irow = 0, *istr = 0;
  Integer              exit_status = 0, i, n, nnz;
  Nag_SparseNsym_Zeros zero;
  Nag_SparseNsym_Dups  dup;
  Nag_NormType         norm;
  NagError             fail;

  INIT_FAIL(fail);

  printf("nag_sparse_nsym_sort (f11zac) Example Program Results\n\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 = 0; i < nnz; ++i)
    scanf("%lf%ld%ld%*[^\n]", &a[i], &irow[i], &icol[i]);

  printf("Original elements \n");
  printf("nnz =  %4ld\n", nnz);
  printf("%8s%16s%8s%8s\n","","a","irow","icol");
  for (i = 0; i < nnz; ++i)
    printf("%8ld%16.4e%8ld%8ld\n", i, a[i],
           irow[i], icol[i]);

  /* Reorder along rows, sum duplicates and remove zeros */

  dup = Nag_SparseNsym_SumDups;
  zero = Nag_SparseNsym_RemoveZeros;

  /* nag_sparse_nsym_sort (f11zac).
   * Sparse sort (nonsymmetric)
   */
  nag_sparse_nsym_sort(n, &nnz, a, irow, icol, dup, zero, istr, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_sparse_nsym_sort (f11zac).\n%s\n",
             fail.message);
      exit_status = 1;
      goto END;
    }

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

  for (i = 0; i < nnz; ++i)
    printf("%8ld%16.4e%8ld%8ld\n", i, a[i],
           irow[i], icol[i]);

  /* Reorder down columns, fail on duplicates or zeros.
   *  Creates CCS storage format as side-effect
   */

  dup = Nag_SparseNsym_FailDups;
  zero = Nag_SparseNsym_FailZeros;
  INIT_FAIL(fail);

  /* nag_sparse_nsym_sort (f11zac).
   * Sparse sort (nonsymmetric)
   */
  nag_sparse_nsym_sort(n, &nnz, a, icol, irow, dup, zero, istr, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_sparse_nsym_sort (f11zac).\n%s\n",
             fail.message);
      exit_status = 1;
      goto END;
    }

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

  for (i = 0; i < nnz; ++i)
    printf("%8ld%16.4e%8ld%8ld\n", i, a[i],
           irow[i], icol[i]);
  printf("%8s%8s\n","","istr");
  for (i = 0; i <= n; ++i)
    printf("%8ld%8ld\n", i, istr[i]);

  /* Calculate 1-norm in Compressed Column Storage format */
  norm = Nag_RealOneNorm;
  INIT_FAIL(fail);

  /* nag_superlu_matrix_norm (f11mlc).
   * 1-norm, infinity-norm, largest absolute element, real
   * general matrix
   */
  nag_superlu_matrix_norm(norm, &anorm, n, istr, irow, a, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_superlu_matrix_norm (f11mlc).\n%s\n",
              fail.message);
      exit_status = 1;
      goto END;
    }
  /* Output norm */
  printf("%s %16.4e\n", "One-norm", anorm);


 END:
  NAG_FREE(istr);
  NAG_FREE(irow);
  NAG_FREE(icol);
  NAG_FREE(a);

  return exit_status;
}