Python 3.5+mathterm

math.inf

constants

Positive infinity (a float). Used as the starting value when searching for a minimum, and in comparisons.

Syntax

math.inf

It is exactly the same value as float('inf'), just easier to read. Arithmetic with it never raises, but it quietly yields nan: math.inf - math.inf and math.inf / math.inf both produce nan rather than an error or zero. Note that dividing by a plain zero in Python does not give infinity — that is still ZeroDivisionError — and int(math.inf) fails with OverflowError.

Examples

import math
print(math.inf)  # → inf
print(-math.inf)  # → -inf
print(math.isinf(math.inf))  # → True
print(math.inf > 10**308)  # → True
print(math.inf + 1)  # → inf
print(math.inf - math.inf)  # → nan

See also

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