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man:expl

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);```
`     Link with -lm.`
` Feature Test Macro Requirements for glibc (see feature_test_macros(7)):`
```     expf(), expl():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE```

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).```
```     allbox; lbw21 lb lb l l l.  Interface Attribute Value T{ exp(), expf(),
expl() T}   Thread safety  MT-Safe```

CONFORMING TO

`     C99, POSIX.1-2001, POSIX.1-2008.`
`     The variant returning double also conforms to SVr4, 4.3BSD, C89.`

SEE ALSO

`     cbrt(3), cexp(3), exp10(3), exp2(3), expm1(3), sqrt(3)`

COLOPHON

```     This page is part of release 4.16 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/.```
`                                2017-09-15                            EXP(3)`
/data/webs/external/dokuwiki/data/pages/man/expl.txt · Last modified: 2019/05/17 09:47 by 127.0.0.1

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