LDEXP(3) BSD Library Functions Manual LDEXP(3)NAME
ldexp, ldexpf — multiply floating-point number by integral power of 2
LIBRARY
Math Library (libm, -lm)
SYNOPSIS
#include <math.h>
double
ldexp(double x, int exp);
float
ldexpf(float x, int exp);
DESCRIPTION
The ldexp() family of functions compute
x * 2^exp
for a real floating-point number x.
RETURN VALUES
The functions return the value of x times 2 raised to the power exp.
Otherwise the following may occur:
1. If x is NaN, a NaN is returned.
2. If exp is zero or x is either ± 0 or ±∞, x is returned.
3. If the call would cause an overflow, a range error occurs and
either ±HUGE_VAL, ±HUGE_VALF, or ±HUGE_VALL is returned,
depending on the sign of x and the type of the return value.
4. If an underflow would be caused by the correct value, and the
value is not representable, either 0.0 or an implementation-
defined value is returned.
SEE ALSOfrexp(3), math(3), modf(3)STANDARDS
The described functions conform to ISO/IEC 9899:1999 (“ISO C99”).
BSD September 18, 2011 BSD