/* nag_sum_sqs (g02buc) Example Program.
 *
 * Copyright 2002 Numerical Algorithms Group.
 *
 * Mark 7, 2002.
 */

#include <stdio.h>
#include <string.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nagf16.h>
#include <nagg02.h>
#include <nagx04.h>

int main(void)
{
  /* Arrays */
  char          nag_enum_mean[40], nag_enum_weight[40];
  double        *c = 0, *v = 0, *wmean = 0, *wt = 0, *x = 0;
  double        *wtptr = 0;
  /* Scalars */
  double        alpha, sw;
  Integer       exit_status, j, k, m, mm, n, pdx;
  Nag_SumSquare mean;
  Nag_Boolean   weight;
  Nag_OrderType order;
  NagError      fail;

#ifdef NAG_COLUMN_MAJOR
#define X(I, J) x[(J-1)*pdx + I - 1]
  order = Nag_ColMajor;
#else
#define X(I, J) x[(I-1)*pdx + J - 1]
  order = Nag_RowMajor;
#endif

  INIT_FAIL(fail);

  exit_status = 0;
  printf("nag_sum_sqs (g02buc) Example Program Results\n");

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

  while (scanf("%s %s %ld%ld%*[^\n]", nag_enum_mean,
                nag_enum_weight, &m, &n) != EOF)
    {
      /* nag_enum_name_to_value(x04nac).
       * Converts NAG enum member name to value
       */
      mean = (Nag_SumSquare) nag_enum_name_to_value(nag_enum_mean);
      weight = (Nag_Boolean) nag_enum_name_to_value(nag_enum_weight);
      /* Allocate memory */
      if (!(c = NAG_ALLOC((m*m+m)/2, double)) ||
          !(v = NAG_ALLOC((m*m+m)/2, double)) ||
          !(wmean = NAG_ALLOC(m, double)) ||
          !(wt = NAG_ALLOC(n, double)) ||
          !(x = NAG_ALLOC(n * m, double)))
        {
          printf("Allocation failure\n");
          exit_status = -1;
          goto END;
        }

#ifdef NAG_COLUMN_MAJOR
      pdx = n;
#else
      pdx = m;
#endif

      for (j = 1; j <= n; ++j)
        scanf("%lf", &wt[j-1]);

      scanf("%*[^\n] ");
      for (j = 1; j <= n; ++j)
        {
          for (k = 1; k <= m; ++k)
            scanf("%lf", &X(j, k));
        }
      scanf("%*[^\n] ");

      if (weight)
        wtptr = wt;

      /* Calculate sums of squares and cross-products matrix */
      /* nag_sum_sqs (g02buc).
       * Computes a weighted sum of squares matrix
       */
      nag_sum_sqs(order, mean, n, m, x, pdx, wtptr, &sw, wmean, c, &fail);
      if (fail.code != NE_NOERROR)
        {
          printf("Error from nag_sum_sqs (g02buc).\n%s\n",
                  fail.message);
          exit_status = 1;
          goto END;
        }

      printf("\n");
      printf("Means\n");
      for (j = 1; j <= m; ++j)
        printf("%14.4f%s", wmean[j-1], j%6 == 0 || j == m?"\n":" ");
      if (wtptr)
        {
          printf("\n");
          printf("Weights\n");
          for (j = 1; j <= n; ++j)
            printf("%14.4f%s", wt[j-1], j%6 == 0 || j == n?"\n":" ");
          printf("\n");
        }

      /* Print the sums of squares and cross products matrix */
      /* nag_pack_real_mat_print (x04ccc).
       * Print real packed triangular matrix (easy-to-use)
       */
      fflush(stdout);
      nag_pack_real_mat_print(Nag_ColMajor, Nag_Upper, Nag_NonUnitDiag, m, c,
                              "Sums of squares and cross-products", 0,
                              &fail);
      if (fail.code != NE_NOERROR)
        {
          printf("Error from nag_pack_real_mat_print (x04ccc).\n%s\n",
                  fail.message);
          exit_status = 1;
          goto END;
        }
      if (sw > 1.0)
        {
          /* Calculate the variance matrix */
          alpha = 1.0 / (sw - 1.0);
          mm = m * (m + 1) / 2;
	  /* v[] = alpha*c[] using 
	   * nag_daxpby (f16ecc)
	   * Multiply real vector by scalar, preserving input vector
	   */
	  nag_daxpby(mm, alpha, c, 1, 0.0, v, 1, &fail);

          /* Print the variance matrix */
          printf("\n");
          /* nag_pack_real_mat_print (x04ccc), see above. */
          fflush(stdout);
          nag_pack_real_mat_print(Nag_ColMajor, Nag_Upper, Nag_NonUnitDiag, m,
                                  v, "Variance matrix", 0, &fail);
          if (fail.code != NE_NOERROR)
            {
              printf(
                      "Error from nag_pack_real_mat_print (x04ccc).\n%s\n",
                      fail.message);
              exit_status = 1;
              goto END;
            }
        }

      if (c) NAG_FREE(c);
      if (v) NAG_FREE(v);
      if (wmean) NAG_FREE(wmean);
      if (wt) NAG_FREE(wt);
      if (x) NAG_FREE(x);
    }

 END:
  if (c) NAG_FREE(c);
  if (v) NAG_FREE(v);
  if (wmean) NAG_FREE(wmean);
  if (wt) NAG_FREE(wt);
  if (x) NAG_FREE(x);

  return exit_status;
}