/* nag_rand_copula_clayton (g05rhc) Example Program.
 *
 * Copyright 2014 Numerical Algorithms Group.
 *
 * Mark 9, 2009.
 */
/* Pre-processor includes */
#include <stdio.h>
#include <math.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nagg05.h>


#define X(I, J) x[order == Nag_ColMajor?((J-1)*pdx + I-1):((I-1)*pdx + J-1)]

int main(void)
{
  /* Integer scalar and array declarations */
  Integer       exit_status = 0;
  Integer       i, j, lstate, pdx, sdx;
  Integer       *state = 0;

  /* Double scalar and array declarations */
  double        *x = 0;

  /* NAG structures */
  NagError      fail;

  /* Use row major order */
  Nag_OrderType order = Nag_RowMajor;

  /* Set the number of variables and variates */
  Integer       n = 13, m = 4;

  /* Choose the base generator */
  Nag_BaseRNG   genid = Nag_Basic;
  Integer       subid = 0;

  /* Set the seed */
  Integer       seed[] = { 1762543 };
  Integer       lseed = 1;

  /* Set the theta parameter value */
  double        theta = 1.3e0;

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

  printf(
          "nag_rand_copula_clayton (g05rhc) Example Program Results\n\n");

  /* Get the length of the state array */
  lstate = -1;
  nag_rand_init_repeatable(genid, subid, seed, lseed, state, &lstate, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_rand_init_repeatable (g05kfc).\n%s\n",
              fail.message);
      exit_status = 1;
      goto END;
    }

  /* Set matrix size and principal dimension according to storage order */
  pdx = (order == Nag_ColMajor)?n:m;
  sdx = (order == Nag_ColMajor)?m:n;

  /* Allocate arrays */
  if (!(x = NAG_ALLOC((pdx*sdx), double)) ||
      !(state = NAG_ALLOC(lstate, Integer)))
    {
      printf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }

  /* Initialise the generator to a repeatable sequence */
  nag_rand_init_repeatable(genid, subid, seed, lseed, state, &lstate, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_rand_init_repeatable (g05kfc).\n%s\n",
              fail.message);
      exit_status = 1;
      goto END;
    }

  /* Generate variates */
  nag_rand_copula_clayton(order, state, theta, n, m, x, pdx, sdx, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_rand_copula_clayton (g05rhc).\n%s\n",
              fail.message);
      exit_status = 1;
      goto END;
    }

  /* Display the results */
  printf("Uniform variates with copula joint distrbution\n");
  for (i = 1; i <= n; i++)
    {
      printf("  ");
      for (j = 1; j <= m; j++)
        printf("%9.6f%s", X(i, j), j < m?" ":"\n");
    }

 END:
  NAG_FREE(x);
  NAG_FREE(state);

  return exit_status;
}