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LDEXP(3)                   Library Functions Manual                   LDEXP(3)

NAME
     ldexp, ldexpf, ldexpl - 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);

     long double
     ldexpl(long double 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 +-<infinity>, 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 ALSO
     frexp(3), math(3), modf(3)

STANDARDS
     The described functions conform to ISO/IEC 9899:1999 ("ISO C99").

NetBSD 10.99                    March 17, 2016                    NetBSD 10.99