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math.exp

constants

Returns e raised to the power of x (the exponential). Equivalent to math.e ** x, but more accurate and faster for large x.

Syntax

math.exp(x)

For large arguments this does not quietly return inf — it raises OverflowError: math range error, roughly above x = 710, so either clamp the input or catch it. Underflow in the other direction is silent and just gives 0.0. When you need exp(x) - 1 for tiny x, use math.expm1(x); the plain subtraction throws away almost all significant digits there.

Examples

import math
print(math.exp(0))   # → 1.0
print(math.exp(1))   # → 2.718281828...
print(math.exp(2))   # → 7.389...
print(math.exp(-1))  # → 0.3678...
print(math.exp(10))  # → 22026.465...
print(math.exp(math.log(5)))  # → ?  (значение зависит от системной libm — карточка учит наличию погрешности, а не её цифрам)

See also

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