/*
 * Copyright (C) 1994. James Darrell McCauley.  (darrell@mccauley-usa.com)
 * 	                                        http://mccauley-usa.com/
 *
 * This program is free software under the GPL (>=v2)
 * Read the file GPL.TXT coming with GRASS for details.
 */

#include<stdio.h>
#include<math.h>
#include"zufall.h"
 
  /* Box-Muller method for Gaussian random numbers */

int 
normalen (int n, double *x)
{
  static int buffsz = 1024;
  extern struct klotz1 klotz1_1;
  int left, i, nn, ptr;

  /* Parameter adjustments */
  --x;

  nn = n;
  if (nn <= 0)
    return 0;

  if (klotz1_1.first == 0)
  {
    normal00 ();
    klotz1_1.first = 1;
  }
  ptr = 0;

L1:
  left = buffsz - klotz1_1.xptr;
  if (nn < left)
  {
    for (i = 1; i <= nn; ++i)
      x[i + ptr] = klotz1_1.xbuff[klotz1_1.xptr + i - 1];
    klotz1_1.xptr += nn;
    return 0;
  }
  else
  {
    for (i = 1; i <= left; ++i)
      x[i + ptr] = klotz1_1.xbuff[klotz1_1.xptr + i - 1];
    klotz1_1.xptr = 0;
    ptr += left;
    nn -= left;
    normal00 ();
    goto L1;
  }
}				/* normalen */
