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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.forth
Subject: Re: Ruby/Forth challenge for WJ
Date: Tue, 12 Jan 2016 14:34:26 -0800
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Chris Curl <ccurl609@gmail.com> writes:
> Since Ruby is so much better than the "toy" language Forth, Ruby can
> do the same thing be much faster than 600ms, right?

Just for laughs, I tried it in Python for 1MB instead of 256MB.  The
random initialization phase took 0.743 sec and the counting phase took
0.009 sec, scaling to about 23 sec for counting 256MB.  The random
initialization was pretty inefficient so I wouldn't count it despite not
seeing an obvious faster way.  The counting phase was the quickest
obvious way I could think of offhand, though maybe there is something
better.  The code is:

    from random import randrange
    import time
    import array
    import itertools

    def main():
        t0 = time.time()
        vec = bytearray(itertools.islice(
            iter(lambda: randrange(0,255), None),
            2**20
        )
        )
        t1 = time.time()
        u = array.array('i',[0]*256)
        for c in vec:
            u[c] += 1
        t2 = time.time()
        print t1-t0, t2-t1

    main()