pythonbooleannegate

How to "negate" value: if true return false, if false return true?

if myval == 0:
   nyval=1
if myval == 1:
   nyval=0

Is there a better way to do a toggle in python, like a nyvalue = not myval ?

Solution

  • Use the not boolean operator:

    nyval = not myval

    not returns a boolean value (True or False):

    >>> not 1
False
>>> not 0
True

    If you must have an integer, cast it back:

    nyval = int(not myval)

    However, the python bool type is a subclass of int, so this may not be needed:

    >>> int(not 0)
1
>>> int(not 1)
0
>>> not 0 == 1
True
>>> not 1 == 0
True