expm1()
The expm1()
function returns e
raised to the power of the argument minus 1. For small magnitudes of x expm1(x)
may be more accurate than exp(x)-1
.
The number e
, also known as Euler’s number, is a mathematical constant approximately equal to 2.71828 and the base of the natural logarithm.
The cmath
library must be added to the top of the file with #include <cmath>
.
Syntax
Returns eⁿ - 1:
std::expm1(n)
Example
Use expm1()
to return the value of e³-1:
double result;result = std::expm1(3);
Codebyte Example
Use expm1()
to return the value of e-1 (e¹-1):