python - Filter list using Boolean index arrays -


how can use boolean inddex arrays filter list without using numpy?

for example:

>>> l = ['a','b','c'] >>> b = [true,false,false] >>> l[b]

the result should be:

['a']

i know numpy support want know how solve in python.

>>> import numpy np >>> l = np.array(['a','b','c']) >>> b = np.array([true,false,false]) >>> l[b] array(['a'],        dtype='|s1')

python not support boolean indexing itertools.compress function want. return iterator means need use list constructor return list.

>>> itertools import compress >>> l = ['a', 'b', 'c'] >>> b = [true, false, false] >>> list(compress(l, b)) ['a']

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