ldexp(3) - NetBSD Manual Pages

Command: Section: Arch: Collection:
```LDEXP(3)                NetBSD 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 ħ 0 or ħoo, x is returned.

3.   If the call would cause an overflow, a range error occurs and
either ħHUGE_VAL, ħHUGE_VALF, or ħHUGE_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.