xref: /freebsd/lib/libc/gen/ldexp.3 (revision 963e8efffe4ab97233102e0e25f95061b6fefbe3)
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36.\"     @(#)ldexp.3	8.2 (Berkeley) 4/19/94
37.\" $FreeBSD$
38.\"
39.Dd March 4, 2005
40.Dt LDEXP 3
41.Os
42.Sh NAME
43.Nm ldexp ,
44.Nm ldexpf ,
45.Nm ldexpl
46.Nd multiply floating-point number by integral power of 2
47.Sh LIBRARY
48.Lb libm
49.Sh SYNOPSIS
50.In math.h
51.Ft double
52.Fn ldexp "double x" "int exp"
53.Ft float
54.Fn ldexpf "float x" "int exp"
55.Ft long double
56.Fn ldexpl "long double x" "int exp"
57.Sh DESCRIPTION
58The
59.Fn ldexp ,
60.Fn ldexpf ,
61and
62.Fn ldexpl
63functions multiply a floating-point number by an integral
64power of 2.
65.Sh RETURN VALUES
66These functions return the value of
67.Fa x
68times 2 raised to the power
69.Fa exp .
70.Sh SEE ALSO
71.Xr frexp 3 ,
72.Xr math 3 ,
73.Xr modf 3
74.Sh STANDARDS
75The
76.Fn ldexp ,
77.Fn ldexpf ,
78and
79.Fn ldexpl
80functions conform to
81.St -isoC-99 .
82