[Numpy-discussion] Find indices of largest elements

Nikolaus Rath Nikolaus@rath....
Thu Apr 15 23:08:10 CDT 2010


eat <e.antero.tammi@gmail.com> writes:
> Nikolaus Rath <Nikolaus <at> rath.org> writes:
>
> [snip]
>> Not quite, because I'm interested in the n largest values over all
>> elements, not the largest element in each row or column. But Keith's
>> solution seems to work fine, even though I'm still struggling to
>> understand what's going on there .
>
> My bad. I just concentrated on your example, not the actual question.
>
> However, what's wrong with your above approach
> "[ np.unravel_index(i, x.shape) for i in idx[-3:] ]" ?
>
> Especially if your n largest elements are just a small fraction of all 
> elements.

The fact that it sorts the entire list. But since for my arrays it's not
really an efficiency problem, I will use it anyway.



Best,

   -Nikolaus

-- 
 »Time flies like an arrow, fruit flies like a Banana.«

  PGP fingerprint: 5B93 61F8 4EA2 E279 ABF6  02CF A9AD B7F8 AE4E 425C



More information about the NumPy-Discussion mailing list