From: Peter Rolf <indiego@gmx.net>
To: Hans Hagen <pragma@wxs.nl>
Cc: mailing list for ConTeXt users <ntg-context@ntg.nl>
Subject: Re: random seed
Date: Wed, 14 Nov 2012 21:15:11 +0100 [thread overview]
Message-ID: <50A3FBCF.8050905@gmx.net> (raw)
In-Reply-To: <50A3EF1A.8010405@wxs.nl>
Am 14.11.2012 20:20, schrieb Hans Hagen:
> On 11/14/2012 7:55 PM, Peter Rolf wrote:
>> Hi,
>>
>> in one of my documents I use a specific random seed to create a fixed
>> random based graphic (size, color, position). This works fine under
>> Windows (where I 'found' the seed value), but I get a complete different
>> result on my Debian system.
>>
>> Is there a way to get identical results on different OS? Or is the
>> random number generator OS specific? Just wondering...
>
> yes and it cannot be trusted either (some underlying os code is used); i
> also found out that you need to call a couple of random's in a row first
> to get at least not the same ones in the beginning
>
> in contetx I've now settled on:
>
> math.initialseed =
> tonumber(string.sub(string.reverse(tostring(ceil(socket and
> socket.gettime()*10000 or time()))),1,6))
>
>
Thanks for the info. The formula looks like an incantation for the god
of random numbers ;-)
I already migrated the tex code to lua, so that I can do some post
processing on the collected random based data. To get identical results,
I only have to save the final data set then.
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prev parent reply other threads:[~2012-11-14 20:15 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-14 18:55 Peter Rolf
2012-11-14 19:20 ` Hans Hagen
2012-11-14 20:15 ` Peter Rolf [this message]
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