/* nag_mv_multidimscal_metric (g03fac) Example Program.
 *
 * Copyright 2024 Numerical Algorithms Group.
 *
 * Mark 30.2, 2024.
 *
 */

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

#define X(I, J) x[(I)*tdx + J]
int main(void) {
  Integer exit_status = 0, i, j, n, ndim, nn, tdx;
  char nag_enum_arg[40];
  double *d = 0, *e = 0, *x = 0;
  Nag_Eigenvalues roots;
  NagError fail;

  INIT_FAIL(fail);

  printf("nag_mv_multidimscal_metric (g03fac) 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
   */
  roots = (Nag_Eigenvalues)nag_enum_name_to_value(nag_enum_arg);

  if (ndim >= 1 && n > ndim) {
    if (!(d = NAG_ALLOC(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 = 0; i < nn; ++i)
    scanf("%lf", &d[i]);

  /* nag_mv_multidimscal_metric (g03fac).
   * Principal co-ordinate analysis
   */
  nag_mv_multidimscal_metric(roots, 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;
  }
  printf("\nScaled Eigenvalues\n\n");

  if (roots == Nag_LargeEigVals) {
    for (i = 0; i < ndim; ++i)
      printf("%10.4f", e[i]);
  } else {
    for (i = 0; i < n; ++i)
      printf("%10.4f", e[i]);
    printf("\n");
  }
  printf("\nCo-ordinates\n\n");
  for (i = 0; i < n; ++i) {
    for (j = 0; j < ndim; ++j)
      printf("%10.4f", X(i, j));
    printf("\n");
  }
END:
  NAG_FREE(d);
  NAG_FREE(e);
  NAG_FREE(x);
  return exit_status;
}