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.Dd $Mdocdate: June 5 2013 $
.Dt LDEXP 3
.Os
.Sh NAME
.Nm ldexp ,
.Nm ldexpf ,
.Nm ldexpl
.Nd multiply floating-point number by integral power of 2
.Sh SYNOPSIS
.In math.h
.Ft double
.Fn ldexp "double x" "int exp"
.Ft float
.Fn ldexpf "float x" "int exp"
.Ft long double
.Fn ldexpl "long double x" "int exp"
.Sh DESCRIPTION
The
.Fn ldexp
function multiplies a floating-point number by an integral
power of 2.
The
.Fn ldexpf
function is a single precision version of
.Fn ldexp .
The
.Fn ldexpl
function is an extended precision version of
.Fn ldexp .
.Sh RETURN VALUES
The
.Fn ldexp ,
.Fn ldexpf
and
.Fn ldexpl
functions return the value of
.Fa x
times 2 raised to the power
.Fa exp .
.Pp
If the resultant value would cause an overflow,
the global variable
.Va errno
is set to
.Er ERANGE
and the value
.Dv HUGE
is returned.
.Sh SEE ALSO
.Xr frexp 3 ,
.Xr modf 3
.Sh STANDARDS
The
.Fn ldexp
function conforms to
.St -ansiC .