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LDEXP(3) | Linux Programmer's Manual | LDEXP(3) |
NAME¶
ldexp, ldexpf, ldexpl - multiply floating-point number by integral power of 2SYNOPSIS¶
#include <math.h>double ldexp(double x, int exp);float ldexpf(float x, int exp);long double ldexpl(long double x, int exp);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
_BSD_SOURCE || _SVID_SOURCE ||
_XOPEN_SOURCE >= 600 || _ISOC99_SOURCE ||
_POSIX_C_SOURCE >= 200112L;
or cc -std=c99
DESCRIPTION¶
The ldexp() function returns the result of multiplying the floating-point number x by 2 raised to the power exp.RETURN VALUE¶
On success, these functions return x * (2^exp).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.
CONFORMING TO¶
C99, POSIX.1-2001. The variant returning double also conforms to SVr4, 4.3BSD, C89.SEE ALSO¶
frexp(3), modf(3), scalbln(3)COLOPHON¶
This page is part of release 3.44 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.2010-09-20 |