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Mail Archives: djgpp/1994/03/12/16:57:46

Subject: Re: rand()
To: djgpp AT sun DOT soe DOT clarkson DOT edu
Date: Sat, 12 Mar 94 12:58:12 PST
From: Eric "Falsch Freiheit" Eisenhart <eric AT nermal DOT santarosa DOT edu>

According to Murle C. Meetze III:
-} >My only remaining problem is with rand(), which always seems to return the
-} >same sequence. Usually there is an initialization routine, but I can't find
-} >it yet.
-}  
-} I am not sure if you know.  From what I am hearing I think 
-} that you know about it.  But of the rand() functions I have 
-} seen most are pseudo-random number generators.  Meaning if you 
-} have a program that prints out 10 random numbers, ever time 
-} you run it you will get the same thing.  It usually has a 
-} function known as a seed or like you said an initialization 
-} function which starts the random number generator.  I haven't 
-} workied with the rand() function on gcc yet, so I can't tell 
-} you what the name of the function is.(the init. one)

If you use rand() then you use srand(int) to initialize it.  If you pass the
same number: srand(42) every time, it will always generate the same sequence
of numbers.  A real good way to get a different sequence every time is to
use "srand(time());" to initialize it.

BTW, in GCC there is a better random number generator: random.  It is the
same to use it, with "srandom()" being the initializer.

-------------------------------------------------------------------------------
Eric Eisenhart/Dr. Fish/Flourescent Floral Flouride <eric AT nermal DOT santarosa DOT edu>
Fortune of the day:
A little inaccuracy sometimes saves tons of explanation.
		-- H. H. Munroe
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