On Fri, Aug 3, 2012 at 2:43 AM, Ian Shannon
<[email protected]> wrote
> NB this also shows that garbage collection or something similar might be 
> affecting the times as I obtain different "curves" running this (and similar) 
> expressions multiple times.

Yes, you get a lot of features from the host OS and the underlying C
library and the machine architecture.

Compare any linear process which takes similar time for similar sized
intermediate results and you could get similar timing distributions.
But since it depends on what else is going on in your OS at the time,
repeatable results can be difficult to obtain.

Intermediate result size is important because modern machines have
hierarchical caches, which in turn have a significant effect on
timing.  You can use 7!:2 to see memory use.

-- 
Raul
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