/* nag_mv_multidimscal_ordinal (g03fcc) Example Program.
 *
 * Copyright 2024 Numerical Algorithms Group.
 *
 * Mark 30.2, 2024.
 *
 */

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

#define NMAX 14

#define X(I, J) x[(I - 1) * tdx + (J - 1)]

int main(void) {
  Integer exit_status = 0, i, j, n, ndim, nn, tdx = NMAX;
  double *d = 0, *dfit = 0, *e = 0, stress, *x = 0;
  char nag_enum_arg[40];
  Nag_ScaleCriterion type;
  NagError fail;

  INIT_FAIL(fail);

  printf("nag_mv_multidimscal_ordinal (g03fcc) Example Program Results\n\n");

  /* Skip heading in data file */
  scanf("%*[^\n]");
  scanf("%" NAG_IFMT "", &n);
  scanf("%" NAG_IFMT "", &ndim);
  scanf("%39s", nag_enum_arg);
  /* nag_enum_name_to_value (x04nac).
   * Converts NAG enum member name to value
   */
  type = (Nag_ScaleCriterion)nag_enum_name_to_value(nag_enum_arg);

  if (ndim >= 1 && n > ndim) {
    if (!(d = NAG_ALLOC(n * (n - 1) / 2, double)) ||
        !(dfit = NAG_ALLOC(4 * (n * (n - 1) / 2), double)) ||
        !(e = NAG_ALLOC(n, double)) || !(x = NAG_ALLOC(n * n, double))) {
      printf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }
    tdx = n;
  } else {
    printf("Invalid ndim or n.\n");
    exit_status = 1;
    return exit_status;
  }
  nn = n * (n - 1) / 2;
  for (i = 1; i <= nn; ++i)
    scanf("%lf", &d[i - 1]);

  /* nag_mv_multidimscal_metric (g03fac).
   * Principal co-ordinate analysis
   */
  nag_mv_multidimscal_metric(Nag_LargeEigVals, n, d, ndim, x, tdx, e, &fail);
  if (fail.code != NE_NOERROR) {
    printf("Error from nag_mv_multidimscal_metric (g03fac).\n%s\n",
           fail.message);
    exit_status = 1;
    goto END;
  }

  /* nag_mv_multidimscal_ordinal (g03fcc).
   * Multidimensional scaling
   */
  nag_mv_multidimscal_ordinal(type, n, ndim, d, x, tdx, &stress, dfit,
                              E04_DEFAULT, &fail);
  if (fail.code != NE_NOERROR) {
    printf("Error from nag_mv_multidimscal_ordinal (g03fcc).\n%s\n",
           fail.message);
    exit_status = 1;
    goto END;
  }

  printf("\n          STRESS = %13.4e\n\n", stress);
  printf("Co-ordinates\n\n");

  for (i = 1; i <= n; ++i) {
    for (j = 1; j <= ndim; ++j)
      printf("%10.4f", X(i, j));
    printf("\n");
  }

END:
  NAG_FREE(d);
  NAG_FREE(dfit);
  NAG_FREE(e);
  NAG_FREE(x);

  return exit_status;
}