expf(3) · carta

Usage

double exp(double x); float expf(float x); long double expl(long double x);

_ISOC99_SOURCE { | | _POSIX_C_SOURCE >= 200112L}

Math library (libm, -lm)

These functions return the value of e (the base of natural logarithms) raised to the power of x.

On success, these functions return the exponential value of x.

If x is a NaN, a NaN is returned.

If x is positive infinity, positive infinity is returned.

If x is negative infinity, +0 is returned.

If the result underflows, a range error occurs, and zero is returned.

If the result overflows, a range error occurs, and the functions return +HUGE_VAL, +HUGE_VALF, or +HUGE_VALL, respectively.

See math_error(7) for information on how to determine whether an error has occurred when calling these functions.

The following errors can occur:

Range error, overflow: errno is set to ERANGE. An overflow floating-point exception (FE_OVERFLOW) is raised.

Range error, underflow: errno is set to ERANGE. An underflow floating-point exception (FE_UNDERFLOW) is raised.

For an explanation of the terms used in this section, see attributes(7).

Interface	Attribute	Value
exp(), expf(), expl()	Thread safety	MT-Safe