built in zip function speed

[Peter Otten]

mart.franklin at gmail.com wrote:

> I hope I am not being too ignorant :p but here goes... my boss has
> written a bit of python code and asked me to speed it up for him...
> I've reduced the run time from around 20 minutes to 13 (not bad I think
> ;) to speed it up further I asked him to replace a loop like this:-
> 
> 
> index = 0
> 
> for element in a:
>    av = a[index]
>    bv = b[index]
>    cv = c[index]
>    dv = d[index]
>    avbv = (av-bv) * (av-bv)
>    diff = cv - dv
>    e.append(diff - avbv)
>    index = index + 1

For /real/ speed-ups use a numerical library, e. g.

# untested
from numarray import array
a = array(a)
b = array(b)
c = array(c)
d = array(d)
e = (c-d) - (a-b)*(a-b)

Peter