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 exp.
On success, these functions return x * (2^exp).
If exp is zero, then x is returned.
If x is a NaN, a NaN is returned.
If 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
x.