Scientific Computing with Python 3

Boolean operations on arrays

You cannot use and, or, and not on Boolean arrays. Indeed, those operators force the casting from array to Boolean, which is not permitted. Instead, we can use the operators given in the following table (Table 5.1) for componentwise logical operations on Boolean arrays:

Logic operator	Replacement for Boolean arrays
A and B	A & B
A or B	A | B
not A	~ A

Table 5.1 Logical operators and, or and not do not work with arrays.

A = array([True, True, False, False])
B = array([True, False, True, False])
A and B # error!
A & B # array([True, False, False, False])
A | B # array([True, True, True, False])
~A # array([False, False, True, True])

Here is an example usage of logical operators with ...