SIMPLE SOLUTIONS

# EXP(3) - man page online | library functions

Base-e exponential function.

Chapter
2015-04-19
```EXP(3)                              Linux Programmer's Manual                              EXP(3)

NAME
exp, expf, expl - base-e exponential function

SYNOPSIS
#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)):

expf(), expl():
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE ||
_POSIX_C_SOURCE >= 200112L;
or cc -std=c99

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

RETURN VALUE
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.

ERRORS
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.

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

┌──────────────────────┬───────────────┬─────────┐
│Interface             │ Attribute     │ Value   │
├──────────────────────┼───────────────┼─────────┤
│exp(), expf(), expl() │ Thread safety │ MT-Safe │
└──────────────────────┴───────────────┴─────────┘
CONFORMING TO
C99, POSIX.1-2001, POSIX.1-2008.

The variant returning double also conforms to SVr4, 4.3BSD, C89.