Exponent function

[Classification]

Mathematical library

[Syntax]

#include <math.h>

double exp(double x);

[Return value]

Returns the xth power of e.

expf returns an denormal number if an underflow occurs (if x is a negative number that cannot express the result), and sets macro ERANGE to global variable errno. If an overflow occurs (if x is too great a number), HUGE_VAL (maximum double type numerics that can be expressed) is returned, and macro ERANGE is set to global variable errno.

[Description]

This function calculates the xth power of e (e is the base of a natural logarithm and is about 2.71828).