Re^5: Predictable random sequence

Hm. Intriguing. It seems that the Windows versions are doing the 'right thing'. Ie. ignoring the argument when you call rand and returning a random float 'tween 0 .. 1.

To get the equivalent behaviour of the built-in rand where the random float is multiplied by the argument, you need to import the function irand().

I cannot see by inspection why (or even how) you get different behaviour on linux?

It seems it should do the same thing as the Windows install:

sub rand
{
    my ($self, $N) = @_;

    unless (ref $self) {
        Math::Random::MT::srand() unless defined $gen;
        $self = $gen;
    }

    return $self->genrand();
}

sub irand
{
    my ($self, $N) = @_;

    unless (ref $self) {
        $N = $self;
        Math::Random::MT::srand() unless defined $gen;
        $self = $gen;
    }

    return ($N || 1) * $self->genirand();
}
[download]

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

Comment on Re^5: Predictable random sequence Download Code

Replies are listed 'Best First'.
Re^6: Predictable random sequence by choroba (Cardinal) on Sep 17, 2013 at 16:06 UTC
I cannot see by inspection why (or even how) you get different behaviour on linux? Different versions of the module? لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ	[reply]
Re^7: Predictable random sequence by BrowserUk (Patriarch) on Sep 17, 2013 at 16:31 UTC
I'm looking at the code on CPAN and comparing it with my local copy and it has barely changed, and as far as I can tell there is no platform dependence that would explain why the OP is getting different results. In fact, beyond a single typedef and the name of a header file, I see no platform dependency at all. Quite how the OP gets the output he posted is beyond my understanding. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply]
Re^8: Predictable random sequence by vsespb (Chaplain) on Sep 18, 2013 at 15:40 UTC
I think this is clearly just a bug, fixed in this version: diff (see changelog and code).	[reply]