ldexp, ldexpf, ldexpl - multiply floating-point number by integral power of 2
#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)):
These functions return the result of multiplying the floating-point number
x by 2 raised to the power
On success, these functions return
x * (2^exp).
exp is zero, then
x is returned.
x is a NaN, a NaN is returned.
x is positive infinity (negative infinity), positive infinity (negative infinity) 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, with a sign the same as
See math_error(7) for information on how to determine whether an error has occurred when calling these functions.
The following errors can occur:
errno is set to ERANGE. An overflow floating-point exception (FE_OVERFLOW) is raised.
errno is set to ERANGE. An underflow floating-point exception (FE_UNDERFLOW) is raised.
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning
double also conforms to SVr4, 4.3BSD, C89.
This page is part of release 4.15 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/.