4.2. Logical operators¶
There are three logical operators:
not. The semantics (meaning) of these
operators is similar to their meaning in English. For example,
x > 0 and x < 10 is true only if
x is greater than 0 and less than 10.
n%2 == 0 or n%3 == 0 is true if either of the conditions
is true, that is, if the number is divisible by 2 or 3.
not operator negates a boolean expression, so
not (x > y) is true if
x > y is false; that
x is less than or equal to
Strictly speaking, the operands of the logical operators should be boolean expressions, but Python is not very strict. Any nonzero number is interpreted as “true.”
This flexibility can be useful, but there are some subtleties to it that might be confusing. You might want to avoid it until you are sure you know what you are doing.