LDEXP(3) Library Functions Manual LDEXP(3)
ldexp, ldexpf -- multiply floating-point number by integral power of 2
Math Library (libm, -lm)
ldexp(double x, int exp);
ldexpf(float x, int exp);
The ldexp() family of functions compute
x * 2^exp
for a real floating-point number x.
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 +-oo, 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.
frexp(3), math(3), modf(3)
The described functions conform to ISO/IEC 9899:1999 (``ISO C99'').
NetBSD 6.1.5 September 18, 2011 NetBSD 6.1.5