/* nag_moving_average (g01wac) Example Program.
 *
 * Copyright 2014 Numerical Algorithms Group.
 *
 * Mark 23, 2011.
 */
/* Pre-processor includes */
#include <stdio.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nagg01.h>

int main(void)
{
  /* Integer scalar and array declarations */
  Integer i, ierr, lrcomm, m, nb, offset, pn, nsummaries;
  Integer exit_status = 0;

  /* NAG structures and types */
  NagError fail;
  Nag_Weightstype iwt;
  Nag_Boolean want_sd;

  /* Double scalar and array declarations */
  double *rcomm = 0, *rmean = 0, *rsd = 0, *x = 0, *wt = 0;

  /* Character scalar and array declarations */
  char                 ciwt[40], cwant_sd[40];

  /* Initialise the error structure */
  INIT_FAIL(fail);

  printf("nag_moving_average (g01wac) Example Program Results\n\n");

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

  /* Read in the problem size */
  scanf("%39s%ld%*[^\n] ",ciwt,&m);
  iwt = (Nag_Weightstype) nag_enum_name_to_value(ciwt);

  /* Read in a flag indicating whether we want the standard deviations */
  scanf("%39s%*[^\n] ",cwant_sd);
  want_sd = (Nag_Boolean) nag_enum_name_to_value(cwant_sd);

  /* Initial handling of weights */
  if (iwt == Nag_WeightWindow) {
    /* Each observation in the rolling window has its own weight */
    if (!(wt = NAG_ALLOC(m, double)))
      {
        printf("Allocation failure\n");
        exit_status = -1;
        goto END;
      }
    for (i = 0; i < m; i++)
      {
        scanf("%lf", &wt[i]);
      }
    scanf("%*[^\n] ");
  }

  /* Allocate memory for the communication array */
  lrcomm = 2*m + 20;
  if (!(rcomm = NAG_ALLOC(lrcomm, double)))
    {
      printf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }

  /* Print some titles */
  if (want_sd)
    {
      printf("                               Standard\n");
      printf("  Interval         Mean        Deviation\n");
      printf(" ---------------------------------------\n");
    }
  else
    {
      printf("  Interval         Mean  \n");
      printf(" ------------------------\n");
    }

  /* Loop over each block of data */
  for (pn = 0;;)
    {
      /* Read in the number of observations in this block */
      ierr = scanf("%"NAG_IFMT, &nb);
      if (ierr == EOF || ierr < 1) break;
      scanf("%*[^\n] ");

      /* Reallocate X to the required size */
      NAG_FREE(x);
      if (!(x = NAG_ALLOC(nb, double)))
        {
          printf("Allocation failure\n");
          exit_status = -1;
          goto END;
        }

      /* Read in the data for this block */
      for (i = 0; i < nb; i++)
        {
          scanf("%lf", &x[i]);
        }
      scanf("%*[^\n] ");

      if (iwt == Nag_WeightObs)
        {
          /* User supplied weights are present */

          /* Reallocate WT to the required size */
          NAG_FREE(wt);
          if (!(wt = NAG_ALLOC(nb, double)))
            {
              printf("Allocation failure\n");
              exit_status = -1;
              goto END;
            }

          /* Read in the weights for this block */
          for (i = 0; i < nb; i++)
            {
              scanf("%lf", &wt[i]);
            }
          scanf("%*[^\n] ");
        }

      /* Calculate the number of summaries we can produce */
      nsummaries = MAX(0,nb + MIN(0,pn-m+1));

      /* Reallocate the output arrays */
      NAG_FREE(rmean);
      if (!(rmean = NAG_ALLOC(nsummaries, double)))
        {
          printf("Allocation failure\n");
          exit_status = -1;
          goto END;
        }
      if (want_sd)
        {
          NAG_FREE(rsd);
          if (!(rsd = NAG_ALLOC(nsummaries, double)))
            {
              printf("Allocation failure\n");
              exit_status = -1;
              goto END;
            }
        }

      /* nag_moving_average (g01wac):
         Calculate the moving average (and optionally the standard deviation)
         for this block of data
      */
      nag_moving_average(m, nb, x, iwt, wt, &pn, rmean, rsd, rcomm, &fail);
      if (fail.code != NE_NOERROR)
        {
          printf("Error from nag_moving_average (g01wac).\n%s\n",
                 fail.message);
          exit_status = -1;
          if (fail.code != NW_POTENTIAL_PROBLEM) goto END;
        }

      /* Number of results printed so far */
      offset = MAX(1,pn-nb-m+2);

      /* Display the results for this block of data */
      if (want_sd)
        {
          for (i = 0; i < nsummaries; i++)
            {
              printf(" [%3ld,%3ld]    "
                     "%10.1f    %10.1f\n",
                     i + offset, i + m + offset - 1, rmean[i], rsd[i]);
            }
        }
      else
        {
          for (i = 0; i < nsummaries; i++)
            {
              printf(" [%3ld,%3ld]    %10.1f\n",
                     i + offset, i + m + offset - 1, rmean[i]);
            }
        }
    }

  printf("\n");
  printf(" Total number of observations : %3ld\n", pn);
  printf(" Length of window             : %3ld\n", m);

 END:
  NAG_FREE(x);
  NAG_FREE(wt);
  NAG_FREE(rmean);
  NAG_FREE(rsd);
  NAG_FREE(rcomm);

  return(exit_status);
}