From: Gabriel Scherer <gabriel.scherer@gmail.com>
To: Hannes Mehnert <hannes@mehnert.org>
Cc: caml-list <caml-list@inria.fr>
Subject: Re: [Caml-list] behaviour of mod
Date: Sun, 18 Jan 2015 20:28:54 +0100 [thread overview]
Message-ID: <CAPFanBENoFpJy7p0wd5CuEKnyof75xgR9t5263g6_gHOdSL3Uw@mail.gmail.com> (raw)
In-Reply-To: <54BBFFF7.6030106@mehnert.org>
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This is at least documented in the manual (
http://caml.inria.fr/pub/docs/manual-ocaml/libref/Pervasives.html ):
> Note that x mod y is negative only if x < 0.
I suppose the idea was to make the least surprising choice (assuming people
knew , and also have the behavior coincide with mod_float. (Interestingly,
the IEEE754 norm requires a "remainder" operation that has an even stranger
behavior (modulo is defined from the round-to-nearest division) and I
haven't proposed anywhere.)
On Sun, Jan 18, 2015 at 7:48 PM, Hannes Mehnert <hannes@mehnert.org> wrote:
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> Hi,
>
> is the behaviour of modulo arithmetics intentional:
> -5 mod 4 = -1 ?
>
> While this reflects the C behaviour, my expectation was to always have
> a positive result:
> -5 mod 4 = 3
>
> Any hints?
>
> hannes
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> --
> Caml-list mailing list. Subscription management and archives:
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next prev parent reply other threads:[~2015-01-18 19:30 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-18 18:48 Hannes Mehnert
2015-01-18 19:28 ` Gabriel Scherer [this message]
2015-01-18 21:06 ` Mr. Herr
2015-01-19 10:59 ` Stephen Dolan
2015-01-20 21:57 ` Yaron Minsky
2015-01-20 21:57 ` Yaron Minsky
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