Numpy: Why is numpy.array([2]).any() > 1 False?

Question

>>> import numpy
>>> numpy.array([2]) > 1
array([ True], dtype=bool)
>>> numpy.array([2]).any() > 1
False

Shouldn't any() test all elements of the array and return True?

seberg · Accepted Answer · 2012-08-21 10:12:25Z

6

It does return True. But (True > 1) == False. While the first part is 2 > 1 which of course is True.

As others posted, you probably want:

(numpy.array([2])  > 1).any()

answered Aug 21, 2012 at 10:04

seberg

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2 Comments

to be exact: numpy.array([2]).any() returns True

So any() should only be used on booleans. I get the idea now. Thanks!

John La Rooy · Accepted Answer · 2012-08-21 10:07:11Z

3

Perhaps you are confusing it with this

>>> (numpy.array([2]) > 1).any()
True

answered Aug 21, 2012 at 10:07

John La Rooy

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