Using the Random Module.

Steven D'Aprano steve at REMOVE-THIS-cybersource.com.au
Sat Jul 12 16:06:09 CEST 2008


On Fri, 11 Jul 2008 12:27:32 -0700, castironpi wrote:

> You want a random integer.  Is there a range you want it in?
> 
> Past a certain point, you'll exceed the granularity of the random number
> generator, and some values in the range will never be generated.

You might want to produce an unbounded random integer, where *every* 
integer has a chance to be returned:

def unbounded_randint():
    i = 0
    while True:
        if random.random() < 0.5:
            return i
        i += 1

This returns 0 with probability 1/2, 1 with probability 1/4, 2 with 
probability 1/8, etc. The probability distribution is centered close to 
zero (the mode and median are both zero, and I'm too lazy to calculate 
the mean) and it has an infinitely long tail.


-- 
Steven



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