/* nag_cov_to_corr (g02bwc) Example Program.
 *
 * Copyright 2002 Numerical Algorithms Group.
 *
 * Mark 7, 2002.
 */

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

int main(void)
{
  /* Scalars */
  double sw;
  Integer exit_status, j, k, m, n, pdx;
  NagError fail;
  Nag_OrderType order;
  Nag_SumSquare mean_enum;

  /* Arrays */
  char mean[2], weight[2];
  double *c=0, *wmean=0, *wt=0, *x=0;
  double *wtptr=0;

#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;
  Vprintf("g02bwc Example Program Results\n");

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

  while (scanf("' %1s ' ' %1s '%ld%ld%*[^\n]", mean, weight, &m, &n) != EOF)
    {
      /* Allocate memory */
      if ( !(c = NAG_ALLOC((m*(m+1))/2, double)) ||
           !(wmean = NAG_ALLOC(m, double)) ||
           !(wt = NAG_ALLOC(n, double)) ||
           !(x = NAG_ALLOC(n * m, double)) )
        {
          Vprintf("Allocation failure\n");
          exit_status = -1;
          goto END;
        }
#ifdef NAG_COLUMN_MAJOR
      pdx = n;
#else
      pdx = m;
#endif
      for (j = 1; j <= n; ++j)
        Vscanf("%lf", &wt[j-1]);
      Vscanf("%*[^\n] ");

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

      if (mean[0] == 'M')
        mean_enum = Nag_AboutMean;
      else if (mean[0] == 'Z')
        mean_enum = Nag_AboutZero;
      else
        {
          Vprintf("Incorrect value for mean\n");
          exit_status = -1;
          goto END;
        }
      if (weight[0] == 'W')
        wtptr = wt;

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

      /* Calculate the correlation matrix */
      g02bwc(m, c, &fail);

      /* Print the correlation matrix */
      if (fail.code == NE_NOERROR)
        {
          Vprintf("\n");
          x04ccc(Nag_ColMajor, Nag_Upper, Nag_NonUnitDiag, m, c,
                 "Correlation matrix", 0, &fail);
          if (fail.code != NE_NOERROR)
            {
              Vprintf("Error from x04ccc.\n%s\n", fail.message);
              exit_status = 1;
              goto END;
            }
        }
      else if (fail.code == NE_ZERO_VARIANCE)
        {
          Vprintf("\n");
          Vprintf("NOTE: some variances are zero\n\n");
          x04ccc(Nag_ColMajor, Nag_Upper, Nag_NonUnitDiag, m, c,
                 "Correlation matrix", 0, &fail);
          if (fail.code != NE_NOERROR)
            {
              Vprintf("Error from x04ccc.\n%s\n", fail.message);
              exit_status = 1;
              goto END;
            }
        }
      else
        {
          Vprintf("Error from g02bwc.\n%s\n",   fail.message);
          exit_status = 1;
          goto END;
        }

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

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

  return exit_status;
}