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I noticed something about the built-in random number generator.

I tried the following:
perl -le'$n=1000000;for(1..$n){$x=rand;$h{$x}++}@b=sort keys %h;$,="\t +";print $h{$b[$_]},$b[$_] for 1..$n;print STDERR scalar @b' > randoms +.txt

This code generates 1000000 random numbers, performs the equivalent of sort | uniq -c on them, prints the unique numbers (with their frequencies) into the file randoms.txt, and also prints how many unique random numbers were generated.

On linux (Perl 5.10.0 coming straight from the Ubuntu 9.04 repo) this prints 1000000, meaning that every random number generated was unique. This was expected.

However, on Windows (Perl 5.10.0, the latest Camelbox build) this prints 32768, meaning that only that many unique numbers were generated and there were many duplicates.

Why is the random number generator so crippled in that particular build? Or is this platform-specific?

In reply to Random numbers are not random enough on Windows by kikuchiyo

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    [ambrus]: Corion: the solution depends on who for. Some non-math presentations need to show lots of graphics or photos, with fine details and color. For those, blackboard or overhead transparencies aren't so good (yes, you can print on transparencies, but there's s
    [ambrus]: ome quality limits), but film projection or computer projector is fine.
    [ambrus]: A minority of math presenters are traditional and don't want to operate a computer. For them, handwritten overhead transparencies and blackboard are fine.
    [Corion]: BTW, has anybody seen the Microsoft Surface Studio thing live?
    [ambrus]: Some will operate a computer, but want to operate crazy unusable android-like GUIs. For those, printed overhead transparencies or simple slide editors and maybe even tablets are fine.
    [ambrus]: Some people like me are fine in learning how to use some custom user interface. For me, I might want to make some keyboard- controlled interactive live slide writer program, like I said in the hypothetical case when I have lots of years of free time for th
    [Corion]: ambrus: Some of my math professors delegated TeX-ing of the exercises etc. to their secretaries :) But they all had very neat handwriting and good blackboard operation anyway ;)
    [ambrus]: is.

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