9.9. operator — Standard operators as functions

The operator module exports a set of efficient functions corresponding to the intrinsic operators of Python. For example, operator.add(x, y) is equivalent to the expression x+y. The function names are those used for special class methods; variants without leading and trailing __ are also provided for convenience.

The functions fall into categories that perform object comparisons, logical operations, mathematical operations, sequence operations, and abstract type tests.

The object comparison functions are useful for all objects, and are named after the rich comparison operators they support:

operator.lt(a, b)

operator.le(a, b)

operator.eq(a, b)

operator.ne(a, b)

operator.ge(a, b)

operator.gt(a, b)

operator.__lt__(a, b)

operator.__le__(a, b)

operator.__eq__(a, b)

operator.__ne__(a, b)

operator.__ge__(a, b)

operator.__gt__(a, b)

Perform “rich comparisons” between a and b. Specifically, lt(a, b) is equivalent to a < b, le(a, b) is equivalent to a <= b, eq(a, b) is equivalent to a == b, ne(a, b) is equivalent to a != b, gt(a, b) is equivalent to a > b and ge(a, b) is equivalent to a >= b. Note that unlike the built-in cmp(), these functions can return any value, which may or may not be interpretable as a Boolean value. See Comparisons for more information about rich comparisons.

New in version 2.2.

The logical operations are also generally applicable to all objects, and support truth tests, identity tests, and boolean operations:

operator.not_(obj)

operator.__not__(obj)

Return the outcome of not obj. (Note that there is no __not__() method for object instances; only the interpreter core defines this operation. The result is affected by the __nonzero__() and __len__() methods.)

operator.truth(obj)

Return True if obj is true, and False otherwise. This is equivalent to using the bool constructor.

operator.is_(a, b)

Return a is b. Tests object identity.

New in version 2.3.

operator.is_not(a, b)

Return a is not b. Tests object identity.

New in version 2.3.

The mathematical and bitwise operations are the most numerous:

operator.abs(obj)

operator.__abs__(obj)

Return the absolute value of obj.

operator.add(a, b)

operator.__add__(a, b)

Return a + b, for a and b numbers.

operator.and_(a, b)

operator.__and__(a, b)

Return the bitwise and of a and b.

operator.div(a, b)

operator.__div__(a, b)

Return a / b when __future__.division is not in effect. This is also known as “classic” division.

operator.floordiv(a, b)

operator.__floordiv__(a, b)

Return a // b.

New in version 2.2.

operator.index(a)

operator.__index__(a)

Return a converted to an integer. Equivalent to a.__index__().

New in version 2.5.

operator.inv(obj)

operator.invert(obj)

operator.__inv__(obj)

operator.__invert__(obj)

Return the bitwise inverse of the number obj. This is equivalent to ~obj.

New in version 2.0: The names invert() and __invert__().

operator.lshift(a, b)

operator.__lshift__(a, b)

Return a shifted left by b.

operator.mod(a, b)

operator.__mod__(a, b)

Return a % b.

operator.mul(a, b)

operator.__mul__(a, b)

Return a * b, for a and b numbers.

operator.neg(obj)

operator.__neg__(obj)

Return obj negated (-obj).

operator.or_(a, b)

operator.__or__(a, b)

Return the bitwise or of a and b.

operator.pos(obj)

operator.__pos__(obj)

Return obj positive (+obj).

operator.pow(a, b)

operator.__pow__(a, b)

Return a ** b, for a and b numbers.

New in version 2.3.

operator.rshift(a, b)

operator.__rshift__(a, b)

Return a shifted right by b.

operator.sub(a, b)

operator.__sub__(a, b)

Return a - b.

operator.truediv(a, b)

operator.__truediv__(a, b)

Return a / b when __future__.division is in effect. This is also known as “true” division.

New in version 2.2.

operator.xor(a, b)