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Message-ID: <477BE419.8080400@gmail.com>
Date: Wed, 02 Jan 2008 13:20:57 -0600
From: Edgar Friendly <thelema314@gmail.com>
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To: Brian Hurt <bhurt@janestcapital.com>
Cc: Kuba Ober <ober.14@osu.edu>, caml-list@yquem.inria.fr
Subject: Re: [Caml-list] [NEWBIE] is there an in-place map?
References: <200801021152.30105.ober.14@osu.edu> <477BC929.4030109@gmail.com> <477BCB94.8060208@janestcapital.com>
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X-Spam: no; 0.00; for-loop:01 recursion:01 recursion:01 recursive:01 arrays:01 edgar:98 wrote:01 clearer:01 ints:01 caml-list:01 arithmetic:01 tail:01 tail:01 data:02 argument:02 

Brian Hurt wrote:
> The OP did say "in place modification.
> 
Kuba also said "the output array is given as the argument, not as a
return value."

> It depends.  If you have to use multiple references to make the for-loop
> work, then I've seen tail recursion be faster (and clearer).  

Any example of a faster tail recursion?

> Also, if
> you recalculate the ending requirement every recursive call, recursion
> can be slower (in the above for loop above, for example, Array.length is
> gaurenteed to be called only once).

I have no problems precalculating the Array.length value, or recursing
down to 0.
> 
> Brian
> 

A little testing results in some data: for arrays of 1024 ints and
simple arithmetic operations, I get a 9% speed increase in using a for
loop over recursion.

E.