Flipping the boolean values in a list Python
I have a boolean list in Python
mylist = [True , True, False,...]
which I want to change to the logical opposite [False, False, True , ...]
Is there an inbuilt way to do this in Python (something like a call not(mylist)
) without a hand-written loop to reverse the elements?
It's easy with list comprehension:
mylist = [True , True, False]
[not elem for elem in mylist]
yields
[False, False, True]
The unary tilde operator (~) will do this for a numpy.ndarray. So:
>>> import numpy
>>> mylist = [True, True, False]
>>> ~numpy.array(mylist)
array([False, False, True], dtype=bool)
>>> list(~numpy.array(mylist))
[False, False, True]
Note that the elements of the flipped list will be of type numpy.bool_ not bool.
>>> import operator
>>> mylist = [True , True, False]
>>> map(operator.not_, mylist)
[False, False, True]