About a list comprehension to transform an input list

[Daniel Urban]

On Fri, Jun 8, 2012 at 6:10 PM, Julio Sergio <juliosergio at gmail.com> wrote:
> >From a sequence of numbers, I'm trying to get a list that does something to even
> numbers but leaves untouched the odd ones, say:
>
> [0,1,2,3,4,...] ==> [100,1,102,3,104,...]
>
> I know that this can be done with an auxiliary function, as follows:
>
> ->>> def filter(n):
> ...     if (n%2 == 0):
> ...         return 100+n
> ...     return n
> ...
> ->>> L = range(10)
> ->>> [filter(n) for n in L]
> [100, 1, 102, 3, 104, 5, 106, 7, 108, 9]
>
> I wonder whether there can be a single list comprehension expression to get this
> result without the aid of the auxiliary function.
>
> Do you have any comments on this?

>>> l = [0,1,2,3,4,5,6,7,8,9]
>>> [n if n%2 else 100+n for n in l]
[100, 1, 102, 3, 104, 5, 106, 7, 108, 9]


Daniel