exp, expf, expl — base-e exponential function
#include <math.h> double exp(double x); float expf(float x); long double expl(long double x);
Link with -lm.
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
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).
|exp(), expf(), expl()||Thread safety||MT-Safe|
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning double also conforms to SVr4, 4.3BSD, C89.
cbrt(3), cexp(3), exp10(3), exp2(3), expm1(3), sqrt(3)
This page is part of release 5.04 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.
erf(3), erfc(3), exp10(3), exp2(3), expm1(3), log1p(3).
The man pages expf(3) and expl(3) are aliases of exp(3).