George Sakkis wrote:
Another alternative is:
from operator import itemgetter
def m3():
colours, nums = zip(*map(itemgetter('colour','num'), l))
It's slower than m1() but faster than m2(); it's also the most
concise, especially if you extract more than two keys.
Good you guys gave me some ideas, I've made m3() work:
def m3()
total = [ [e['colour'], e['num'], e['couleur']] for e in l ]
c,d,e = zip(*total)
return map(list, [c,d,e])
(I have to transform to lists, I need to transform them later on, so tuples
won't work).
Unfortunately the timing is inconsistant, the first time I run
python -m timeit 'import listcomp ; listcomp.m1()'
m1 is the fastest. But then if I run the test several times, they all seem
to be about the same time ; I'll have to try with a large list.
Now here is a question:
Is there any way to change my first line there for the list comp. to return
a list of lists rather than a list of tuples ?
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