xref: /freebsd/lib/libc/gen/ldexp.3 (revision cbb3ec25236ba72f91cbdf23f8b78b9d1af0cedf)
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32.\"     @(#)ldexp.3	8.2 (Berkeley) 4/19/94
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34.Dd March 4, 2005
35.Dt LDEXP 3
36.Os
37.Sh NAME
38.Nm ldexp ,
39.Nm ldexpf ,
40.Nm ldexpl
41.Nd multiply floating-point number by integral power of 2
42.Sh LIBRARY
43.Lb libm
44.Sh SYNOPSIS
45.In math.h
46.Ft double
47.Fn ldexp "double x" "int exp"
48.Ft float
49.Fn ldexpf "float x" "int exp"
50.Ft long double
51.Fn ldexpl "long double x" "int exp"
52.Sh DESCRIPTION
53The
54.Fn ldexp ,
55.Fn ldexpf ,
56and
57.Fn ldexpl
58functions multiply a floating-point number by an integral
59power of 2.
60.Sh RETURN VALUES
61These functions return the value of
62.Fa x
63times 2 raised to the power
64.Fa exp .
65.Sh SEE ALSO
66.Xr frexp 3 ,
67.Xr math 3 ,
68.Xr modf 3
69.Sh STANDARDS
70The
71.Fn ldexp ,
72.Fn ldexpf ,
73and
74.Fn ldexpl
75functions conform to
76.St -isoC-99 .
77