x=: 1e6 $ ' '
y=: a. {~ ? 1e6 $ 256
%/ 100 (6!:2)&> '/:~x' ; '/:~y'
2.07821
64-bit Ubuntu Linux, Intel Core i5-2450M
On Tue, Jul 8, 2014 at 2:30 AM, Nollaig MacKenzie <[email protected]
> wrote:
> Intense PC (64 bit Intel core i7) j701/2011-01-10/11:25
>
> 1.43 - 1.45
>
> Mac Mini OS X 10.9.3
>
> 1.11 - 1.18
>
>
>
> On 2014.07.04 22:59:29, you,
> the extraordinary Roger Hui, spake thus:
>
> > From: Roger Hui <[email protected]>
> > Subject: [Jprogramming] sort times
> > Date: Fri, 4 Jul 2014 22:59:29 -0700
> > To: Programming forum <[email protected]>
> >
> > I have observed a puzzling timing result which may be CPU dependent.
> > Please try the following and tell me what ratio you get, and the kind of
> > machine you ran it on. Thanks.
> >
> > On my machine, an XPS L521X Intel Core i7-3632QM @ 2.2 GHz,
> >
> > x=: 1e6 $ ' '
> > y=: a. {~ ? 1e6 $ 256
> > %/ 100 (6!:2)&> '/:~x' ; '/:~y'
> > 2.44133
> >
> > Basically, sorting a constant vector of 1-byte ints takes 2.4 times as
> long
> > as sorting a random vector of 1-byte ints.
> > ----------------------------------------------------------------------
> > For information about J forums see http://www.jsoftware.com/forums.htm
>
> --
> Nollaig MacKenzie
> http://www.yorku.ca/nollaig
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
>
----------------------------------------------------------------------
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