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[Caml-list] floating point input/conversion
-
Stefan Ratschan
- Olivier Andrieu
- Christophe Raffalli
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| Date: | -- (:) |
| From: | Christophe Raffalli <christophe.raffalli@u...> |
| Subject: | Re: [Caml-list] floating point input/conversion |
Stefan Ratschan wrote: > For the functions float_of_string and read_float the OCaml manual is > very vague: "Convert the given string to a float". > > In fact, this sentence is wrong. For example, the number 0.1 does not > have a floating point representation, only approximations to it. > Probably worst is the conversion from num to float (Num.float_of_num) which goes (or at least used to, I did not check 3.08.1) through decimal representation as a string and is therefore not in constant time as it could. This prevents a good implementation of what is called "lazy rational number" (you compute a float, but if it is not precise enough, then you compute an exact rational number) -- Christophe Raffalli Université de Savoie Batiment Le Chablais, bureau 21 73376 Le Bourget-du-Lac Cedex tél: (33) 4 79 75 81 03 fax: (33) 4 79 75 87 42 mail: Christophe.Raffalli@univ-savoie.fr www: http://www.lama.univ-savoie.fr/~RAFFALLI --------------------------------------------- IMPORTANT: this mail is signed using PGP/MIME At least Enigmail/Mozilla, mutt or evolution can check this signature. The public key is stored on www.keyserver.net ---------------------------------------------