list subsetting
Robert Kern
robert.kern at gmail.com
Wed Jan 21 17:47:56 EST 2009
culpritNr1 wrote:
> Thank you Fogelbird and Jeff.
>
> I actually tried to find out if such function existed. I did
>
>>>> help("count")
> no Python documentation found for 'count'
>
> Anyway. More than counting, I am interested in list subsetting in a simple
> way. Forget about counting. Say I have a list of lists and I want to pull
> only the rows where the second "column" equals 3.14.
In [1]: list_o_lists = [[1, 3.14, 3, 4],
...: [2, 3, 4, 5],
...: [3, 3.14, 5, 6]]
In [2]: print [L for L in list_o_lists if L[1] == 3.14]
[[1, 3.1400000000000001, 3, 4], [3, 3.1400000000000001, 5, 6]]
--
Robert Kern
"I have come to believe that the whole world is an enigma, a harmless enigma
that is made terrible by our own mad attempt to interpret it as though it had
an underlying truth."
-- Umberto Eco
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