exp, expf, expl - base-e exponential function
#include <math.h> double exp(double x); float expf(float x); long double expl(long double x);
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
On success, these functions return the exponential value of
x is a NaN, a NaN is returned.
x is positive infinity, positive infinity is returned.
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:
errno is set to ERANGE. An overflow floating-point exception (FE_OVERFLOW) is raised.
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.
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