LISTS: Extract every other element - SUMMARY

[Christian Tismer]

Mike Fletcher wrote:
> 
> Not with my testing on the code-as-given (incidentally, code as given had a
> nameerror on p in the second loop setup).  I get:

Oops, I really thought a loop initilizes its variable always.
Thanks! :-)

> 
> 1.098 -- algo7
> 1.052 -- for with multiply
> 1.134 -- for with divide
> 0.421 -- matrix step-slice
> 0.428 -- matrix reshape
> 

What funny machine/Python do you have ???
Algo 7 is 2.5 times faster on my P200 /Py1.5.2/Windooze.
Here Algo 8 vs. Algo 7: (as expected):

>>> timing(algo7, data, 10)[0]
1.15
>>> timing(algo8, data, 10)[0]
1.1
>>> 

Hääh? Stunned-ly y'rs - chris

-- 
Christian Tismer             :^)   <mailto:tismer at appliedbiometrics.com>
Applied Biometrics GmbH      :     Have a break! Take a ride on Python's
Kaiserin-Augusta-Allee 101   :    *Starship* http://starship.python.net
10553 Berlin                 :     PGP key -> http://wwwkeys.pgp.net
PGP Fingerprint       E182 71C7 1A9D 66E9 9D15  D3CC D4D7 93E2 1FAE F6DF
     we're tired of banana software - shipped green, ripens at home