# Function libm::expm1 [−][src]

pub fn expm1(x: f64) -> f64

Exponential, base *e*, of x-1 (f64)

Calculates the exponential of `x`

and subtract 1, that is, *e* raised
to the power `x`

minus 1 (where *e* is the base of the natural
system of logarithms, approximately 2.71828).
The result is accurate even for small values of `x`

,
where using `exp(x)-1`

would lose many significant digits.