exp(3) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | ATTRIBUTES | CONFORMING TO | SEE ALSO | COLOPHON

EXP(3)                    Linux Programmer's Manual                   EXP(3)

NAME top

       exp, expf, expl - base-e exponential function

SYNOPSIS top

       #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 top

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

RETURN VALUE top

       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 top

       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 top

       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 top

       C99, POSIX.1-2001, POSIX.1-2008.

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

SEE ALSO top

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

COLOPHON top

       This page is part of release 5.08 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)

Pages that refer to this page: erf(3) , erfc(3) , erfcf(3) , erfcl(3) , erff(3) , erfl(3) , exp10(3) , exp10f(3) , exp10l(3) , exp2(3) , exp2f(3) , exp2l(3) , expm1(3) , expm1f(3) , expm1l(3) , log1p(3) , log1pf(3) , log1pl(3)