src/common/random.h

/* Copyright (c) 1998 Silicon Graphics, Inc. */

/* SCCSid "$SunId$ SGI" */

/*
 *  random.h - header file for random(3) and urand() function.
 *
 *     10/1/85
 */

#ifdef  MSDOS

#define random()        ((long)rand()<<16^(long)rand()<<6^(long)rand()>>4)

#define frandom()       (rand()*(1./32768.))

#else
#ifdef  BSD

extern long  random();

#define  frandom()      (random()*(1./2147483648.))

#else

extern long  lrand48();
extern double  drand48();

#define  random()       lrand48()
#define  frandom()      drand48()

#endif
#endif

#ifdef  MC

#define  urand(i)       frandom()
#define  initurand(n)   (n)

#else

extern unsigned short   *urperm;
extern int      urmask, initurand();

#define  urand(i)       ((urperm[(i)&urmask]+frandom())/(urmask+1))

#endif
Revision:	2.6
Committed:	Mon Jan 5 16:42:49 1998 UTC (26 years, 3 months ago) by gregl
Content type:	text/plain
Branch:	MAIN
Changes since 2.5:	+2 -2 lines
Log Message:	added check for too many urand values
#	User	Rev	Content
1	gregl	2.6	/* Copyright (c) 1998 Silicon Graphics, Inc. */
2	greg	1.1
3	gregl	2.5	/* SCCSid "$SunId$ SGI" */
4	greg	1.1
5			/*
6	greg	1.4	* random.h - header file for random(3) and urand() function.
7	greg	1.1	*
8			* 10/1/85
9			*/
10
11	greg	2.2	#ifdef MSDOS
12	greg	1.3
13	greg	2.3	#define random() ((long)rand()<<16^(long)rand()<<6^(long)rand()>>4)
14	greg	2.2
15			#define frandom() (rand()*(1./32768.))
16
17			#else
18			#ifdef BSD
19
20	greg	1.1	extern long random();
21
22	greg	2.2	#define frandom() (random()*(1./2147483648.))
23	greg	1.3
24			#else
25
26			extern long lrand48();
27			extern double drand48();
28
29	greg	2.2	#define random() lrand48()
30			#define frandom() drand48()
31	greg	1.3
32			#endif
33	greg	2.2	#endif
34	greg	1.4
35	greg	2.4	#ifdef MC
36	gregl	2.5
37	greg	2.4	#define urand(i) frandom()
38	gregl	2.5	#define initurand(n) (n)
39
40	greg	2.4	#else
41	gregl	2.5
42	gregl	2.6	extern unsigned short *urperm;
43	gregl	2.5	extern int urmask, initurand();
44
45	greg	2.2	#define urand(i) ((urperm[(i)&urmask]+frandom())/(urmask+1))
46	gregl	2.5
47	greg	2.4	#endif