pythonic array subsetting

[Nick Matzke]

Hi,

So I've got a square floating point array that is about 1000 x 1000. I
need to subset this array as efficiently as possible based on an
ordered sublist of the list of rownames/colnames (they are the same,
this is a symmetric array).

e.g., if sublist is of length 500, and matches the rownames list at
every other entry, I need to pull out a 500x500 array holding every
other row & column in the parent array.

I have to do this hundreds of times, so speed would be useful.

Cheers!
Nick



--
====================================================
Nicholas J. Matzke
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Huelsenbeck Lab
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[bearophileHUGS]

Nick Matzke:

I have to do this hundreds of times, so speed would be useful.

Try to create a 2D array with NumPy, and then slice it. Note that
slicing syntax has a "stride" too.

Bye,
bearophile