Random numbers in metapost

Random numbers in metapost

[David Arnold]

Hi,

Does anyone have any strategies for drawing random numbers from various statistics distributions in Metapost? For example, say, drawing 100 random numbers from a beta distribution?

David
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Re: Random numbers in metapost

[Taco Hoekwater]

David Arnold wrote:
> Hi,
> 
> Does anyone have any strategies for drawing random numbers from
> various statistics distributions in Metapost? For example, say,
> drawing 100 random numbers from a beta distribution?

Assuming you are using mkiv: create a lua function and use its
calculated results to create the metapost code. Metapost only knows
about uniformdeviate and normaldeviate, and metapost is not a good
language to program mathematics in.

Best wishes,
Taco
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Re: Random numbers in metapost

[David Arnold]

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Taco et al,

I think I've found a way. Anthony Phan has written a brilliant stats package for Metapost.

http://www-math.univ-poitiers.fr/~phan/statsmac.html

I think (haven't tried yet) I can select a number at random from the uniform distribution on [0,1], then use one of Anthony's functions such as:

poissonicdf(expr p, lambda). Inverse cumulative distribution function of P(lambda).

See Anthony's manual at:

http://www-math.univ-poitiers.fr/~phan/downloads/metapost/statsman.pdf

David.


On Dec 31, 2009, at 5:13 AM, Taco Hoekwater wrote:

> David Arnold wrote:
>> Hi,
>> Does anyone have any strategies for drawing random numbers from
>> various statistics distributions in Metapost? For example, say,
>> drawing 100 random numbers from a beta distribution?
> 
> Assuming you are using mkiv: create a lua function and use its
> calculated results to create the metapost code. Metapost only knows
> about uniformdeviate and normaldeviate, and metapost is not a good
> language to program mathematics in.
> 
> Best wishes,
> Taco
> ___________________________________________________________________________________
> 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
> webpage  : http://www.pragma-ade.nl / http://tex.aanhet.net
> archive  : http://foundry.supelec.fr/projects/contextrev/
> wiki     : http://contextgarden.net
> ___________________________________________________________________________________


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