Consistent random number generation

Consistent random number generation

[Aditya Mahajan]

Hi,

Is it possible to generate consistent random numbers across multiple 
operating systems. For example, consider the following file:

math.randomseed(1000)
print(math.random())
print(math.random())
print(math.random())

If I process this using texlua, the output on linux and MacOS is 
different. Is it possible to get consistent output?

Rationate: I use randomization to randomize certain paths in metapost. Not 
all randomly generated paths look okay, so I play around with the seed 
until I get a good path. But I have to repeat this process everytime I 
update my distribution and if I compile on different machines.

Thanks,
Aditya
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Re: Consistent random number generation

[Alan BRASLAU]

On Tue, 5 Apr 2016 17:43:53 -0400
Aditya Mahajan <adityam@umich.edu> wrote:

> Is it possible to generate consistent random numbers across multiple 
> operating systems.

Then they are not random!

Why not save your chosen "random" paths to files?

Alan
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Re: Consistent random number generation

[Norbert Melzer]

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In programming usually a (non-crypto-safe) RNG returns the same sequence
everytime it is started with the same seed. Therefore, you often seed with
the current time if you do not want to have reproducable sequences and use
a specific seed when you want reproducable results across certain runs.

There are meany causes to want to have this deterministic “randomnes”:

* As mentioned in this thread: reproducable results across different
systems, OSs and architectures
* Certain kinds of games do transfer/save a base seed instead of the
randomly generated level to save bandwith/diskspace

There are more examples, but in the end, they all rely on reproducing the
sequence over multiple architectures to recreate something exactly the same
way it was before.



Alan BRASLAU <alan.braslau@cea.fr> schrieb am Mi., 6. Apr. 2016 um
03:01 Uhr:

> On Tue, 5 Apr 2016 17:43:53 -0400
> Aditya Mahajan <adityam@umich.edu> wrote:
>
> > Is it possible to generate consistent random numbers across multiple
> > operating systems.
>
> Then they are not random!
>
> Why not save your chosen "random" paths to files?
>
> Alan
>
> ___________________________________________________________________________________
> If your question is of interest to others as well, please add an entry to
> the Wiki!
>
> maillist : ntg-context@ntg.nl /
> http://www.ntg.nl/mailman/listinfo/ntg-context
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> archive  : http://foundry.supelec.fr/projects/contextrev/
> wiki     : http://contextgarden.net
>
> ___________________________________________________________________________________

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