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PSX_RAND
- Generate a random number
- Description:
- Generate a random number. The number is generated as the integer
INUM. The maximum value that this may have is returned as MAXNUM.
Also the value of INUM divided by MAXNUM is returned as FNUM.
- Invocation:
- CALL PSX_RAND( INUM, MAXNUM, FNUM, STATUS )
- Arguments:
-
-
INUM = INTEGER (Returned)
-
The random (integer) number.
-
MAXNUM = INTEGER (Returned)
-
The maximum value that INUM may have.
-
FNUM = REAL (Returned)
-
The value INUM/MAXNUM.
-
STATUS = INTEGER (Given)
-
The global status.
- Notes:
- A seed for the random number generator may be set with
PSX_SRAND.
- The sequence of numbers generated by the operating system
service that is called by this routine is not always as random
as it should be. It is probably better to use a different
routine such as one of the NAG routines. This routine is
included here for completeness, though.
-
References
- POSIX standard (1988), section 8.1
- ANSI C standard (1989), section 4.10.2.1
-
Copyright
- Copyright (C) 1991 Science & Engineering Research Council
Next: PSX_REALLOC - Change the size of an allocated region of virtual memory
Up: Routine Descriptions
Previous: PSX_PUTENV - Set a new environment variable value
PSX POSIX interface routines
Starlink User Note 121
P M Allan
A J Chipperfield
10 April 2003
E-mail:ussc@star.rl.ac.uk
Copyright © 2000 Council for the Central Laboratory of the Research Councils