From: briand@aracnet.com
To: malc <malc@pulsesoft.com>
Cc: caml-list@inria.fr
Subject: Re: [Caml-list] interesting array efficiency observations
Date: Mon, 10 May 2004 22:04:13 -0700 [thread overview]
Message-ID: <16544.24269.920791.984825@soggy.deldotd.com> (raw)
In-Reply-To: <Pine.LNX.4.55.0405091806550.573@home.oyster.ru>
Perfect.
Thanks for the link.
However, I have a question :-)
>From the link:
let f a x y = 1 + a.{x,y}
has a polymorphic type (int, 'a, 'b) Bigarray.Array2.t -> int -> int -> int
and compiles down to a library function call. However,
open Bigarray
let f (a : (int, int_elt, c_layout) Array2.t) x y = 1 + a.{x,y}
is monomorphic and will be compiled much more efficiently by ocamlopt.
So what if I have declared a variable, i.e.
let the_a = Bigarray.Array2.create Bigarray.float64 Bigarray.c_layout 5 5;;
and now I invoke f
f the_a 1 2
Why would the_a be treated polymorphically ??
the_a is very clearly defined as a very specific Bigarray and so the
compiler will know this in the call to f, and will do the correct
thing, right ?
Isn't the type annotation in the function redundant in such a case ?
Thanks
Brian
>>>>> "malc" == malc <malc@pulsesoft.com> writes:
malc> On Sat, 8 May 2004 briand@aracnet.com wrote:
>> I was investigating the use of 1-D bigarray's vs Array and
>> noticed that the 1-D bigarray using c_layout seems to be slower
>> than Array.
malc> http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=ISO-8859-1&threadm=fa.hj2u7jv.t1ms25%40ifi.uio.no&rnum=1&prev=/groups%3Fq%3Dfa.caml%2Bbigarray%2Bmalc%26hl%3Den%26lr%3D%26ie%3DUTF-8%26oe%3DISO-8859-1%26selm%3Dfa.hj2u7jv.t1ms25%2540ifi.uio.no%26rnum%3D1
malc> -- mailto:malc@pulsesoft.com
-------------------
To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr
Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/
Beginner's list: http://groups.yahoo.com/group/ocaml_beginners
next prev parent reply other threads:[~2004-05-11 5:04 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-05-08 18:13 briand
2004-05-08 21:21 ` Yamagata Yoriyuki
2004-05-08 22:45 ` Olivier Grisel
2004-05-09 0:25 ` Christophe TROESTLER
2004-05-09 0:48 ` Yamagata Yoriyuki
2004-05-09 8:24 ` Xavier Leroy
2004-05-09 14:07 ` malc
2004-05-11 5:04 ` briand [this message]
2004-05-12 15:30 ` Christophe TROESTLER
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=16544.24269.920791.984825@soggy.deldotd.com \
--to=briand@aracnet.com \
--cc=caml-list@inria.fr \
--cc=malc@pulsesoft.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).