How to filter a numpy array using another array's values?

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Chapters
00:00 How To Filter A Numpy Array Using Another Array'S Values?
00:31 Accepted Answer Score 42
00:50 Answer 2 Score 3
01:07 Thank you

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Full question
https://stackoverflow.com/questions/9296...

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Tags
#python #arrays #filter #numpy

#avk47

ACCEPTED ANSWER

Score 42

NumPy supports boolean indexing

a[f]

This assumes that a and f are NumPy arrays rather than Python lists (as in the question). You can convert with f = np.array(f).

ANSWER 2

Score 3

If you don't already need numpy arrays, here's with a plain list:

import itertools
print itertools.compress(a, f)

For pre-2.7 versions of python, you must roll your own (see manual):

def compress(data, selectors):
    return (d for d, s in itertools.izip(data, selectors) if s)