Section (3) exp
exp, expf, expl — base-e exponential function
||long double x
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
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_VALF, or +
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
errnois set to ERANGE. An overflow floating-point exception (
FE_OVERFLOW) is raised.
- Range error, underflow
errnois 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).
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning double also conforms to SVr4, 4.3BSD, C89.
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Linux libc source code
Lewine_zsingle_quotesz_s _POSIX Programmer_zsingle_quotesz_s Guide_ (O_zsingle_quotesz_Reilly & Associates, 1991)
386BSD man pages
Modified 1993-07-24 by Rik Faith (faithcs.unc.edu)
Modified 1995-08-14 by Arnt Gulbrandsen <agulbratroll.no>
Modified 2002-07-27 by Walter Harms