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/*
* 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 */
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