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From: Gerben Wierda <gerben.wierda@rna.nl>
To: mailing list for ConTeXt users <ntg-context@ntg.nl>
Subject: METAPOST's uniformdeviate is not truly random (seed)
Date: Tue, 23 Jun 2020 17:57:59 +0200	[thread overview]
Message-ID: <02E331D9-C3E8-456D-B6EE-CD26E8E09C56@rna.nl> (raw)

I’m trying to get a real random number in METAPOST

MWE:

\startMPpage[instance=doublefun]
show uniformdeviate 60;
\stopMPpage

Every time I run this, it shows the same result. I tried playing around with the randomseed, but for instance when I do two runs shortly after each other they still are very predictable. E.g. this in METAPOST:

  whatever = lua( "math.randomseed( tonumber(tostring(os.time()):reverse():sub(1,6)) )");
  randomseed := lua.math.random();
  minutespast := uniformdeviate 60;

Called shortly after each other (two LMTX runs) gets me the same result.

What is a good way to get better random numbers in METAPOST (LMTX)?

Thanks,

G
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             reply	other threads:[~2020-06-23 15:57 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-23 15:57 Gerben Wierda [this message]
2020-06-23 16:14 ` Wolfgang Schuster

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