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[Caml-list] doing MMX through ocaml
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Date: 2005-11-17 (22:43)
From: Daniel_Bünzli <daniel.buenzli@e...>
Subject: Re: [Caml-list] doing MMX through ocaml

Le 17 nov. 05 ŕ 23:16, Damien Bobillot a écrit :

> PS : I think it will perhaps have the same problems as floating  
> computation, which is not really efficient. As far as I know,  
> floats are not stored as float in memory, but as a generic ocaml  
> value  : a pointer to a structure contains a tag indicating that  
> it's a float, and after the IEEE float value.

This not exactly true. As an exception, they are unboxed in records  
and arrays made of floats only [1,2].

Note that you can also use bigarrays [3] to have unboxed arrays of  
any scalar datatype.

This page [4] (unfortunately not available in the faq of the new  
ocaml site) contains interesting information about writing numerical  
code in ocaml.



[1] <http://caml.inria.fr/pub/docs/manual-ocaml/manual032.html#htoc218>
[2] <http://caml.inria.fr/pub/docs/manual-ocaml/manual032.html#htoc219>
[3] <http://caml.inria.fr/pub/docs/manual-ocaml/manual043.html#htoc261>
[4] <http://caml.inria.fr/pub/old_caml_site/ocaml/numerical.html>