[Jprogramming] j701 Speed Test

[Devon McCormick]

Part of the reason for the variability is that you're generating a new
matrix each time and including the generation in your timing.
Something like this should give a more stable result:

   6!:2 '%.mat' [ mat=. 50 50?.@$1000

Also, this form better allows you to run multiple timings to get a
more stable number, e.g.:

   (10) 6!:2 '%.mat'

On Mon, Sep 10, 2012 at 3:29 PM, Robert Cyr <robert.cyr at gmail.com> wrote:
> Results of the posted benchmark vary quie a bit: on this Nexus 7,
>
> 6!:2'%.50 50 ?.@$1000'
> 0.043118
>
>   6!:2'%.50 50 ?.@$1000'
> 0.033788
>
>   6!:2'%.50 50 ?.@$1000'
> 0.030006
>
>   6!:2'%.50 50 ?.@$1000'
> 0.034632
>
>   6!:2'%.50 50 ?.@$1000'
> 0.023798
>
>   And with a larger sample,
>
>   6!:2'%.500 500 ?.@$1000'
> 7.91767
>
>   6!:2'%.500 500 ?.@$1000'
> 8.07115
>
>   6!:2'%.500 500 ?.@$1000'
> 7.94837
>
> About twice the time of the iPad
>  On Sep 9, 2012 6:53 AM, "bill lam" <bbill.lam at gmail.com> wrote:
>
>> From google, iphone 4 uses cortex-a8 and that cpu uses vfp-lite which
>> is 10 times slower than a regular vfp used in cortex-a9.
>>
>> Сбт, 08 Сен 2012, Joey K Tuttle писал(а):
>> > That's a nice speedup! It will be interesting to try the iPhone 5.
>> >
>> > I'm curious if anyone has a timing from a generation 3 iPad, it may
>> > well be faster than my iPad 2.
>> >
>> > On 2012/09/08 06:30 , J. Patrick Harrington wrote:
>> > >
>> > >The iPhone 4S is faster: 5.6 sec
>> > >
>> > >On Fri, 7 Sep 2012, Joey K Tuttle wrote:
>> > >>iPhone 4   -  18.2 seconds
>> > >>iPad 2     -   4.6 seconds
>> > >>
>> > >>On 2012/09/07 19:48 , bill lam wrote:
>> > >>>I am curious to know what are the timings for iphone and ipad.
>> > >>>
>> > >>>It is around 6 to 11 seconds on android depending on CPU.
>> > >>>
>> > >>>Срд, 05 Сен 2012, Paul Jackson писал(а):
>> > >>>>Some time ago, you and Roger were talking about timings on
>> > >>>>     %. 500 500 ?@$ 1000
>> > >>>>
>> > >>>>I believe Roger said he had timings from the IPSA days.  He also
>> > >>>>said the
>> > >>>>matix was considerably smaller.  Did you ever get those early machine
>> > >>>>timings?
>> > >>>>
>> > >>>>Paul
>> > ----------------------------------------------------------------------
>> > For information about J forums see http://www.jsoftware.com/forums.htm
>>
>> --
>> regards,
>> ====================================================
>> GPG key 1024D/4434BAB3 2008-08-24
>> gpg --keyserver subkeys.pgp.net --recv-keys 4434BAB3
>> ----------------------------------------------------------------------
>> For information about J forums see http://www.jsoftware.com/forums.htm
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm



-- 
Devon McCormick, CFA
^me^ at acm.
org is my
preferred e-mail