Are there builtin functions for elementwise boolean operators over boolean lists?

python list built-in boolean-operations elementwise-operations
bshanks picture bshanks · May 5, 2010 · Viewed 26.9k times · Source

For example, if you have n lists of bools of the same length, then elementwise boolean AND should return another list of that length that has True in those positions where all the input lists have True, and False everywhere else.

It's pretty easy to write, i just would prefer to use a builtin if one exists (for the sake of standardization/readability).

Here's an implementation of elementwise AND:

def eAnd(*args):
    return [all(tuple) for tuple in zip(*args)]

example usage:

>>> eAnd([True, False, True, False, True], [True, True, False, False, True], [True, True, False, False, True])
[True, False, False, False, True]

Answer

Mike Graham picture Mike Graham · May 5, 2010

There is not a built-in way to do this. Generally speaking, list comprehensions and the like are how you do elementwise operations in Python.

Numpy does provide this (using &, for technical limitations) in its array type. Numpy arrays usually perform operations elementwise.

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