xref: /dragonfly/lib/libc/gen/ldexp.3 (revision 0de61e28)
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32.\"     @(#)ldexp.3	8.2 (Berkeley) 4/19/94
33.\" $FreeBSD: head/lib/libc/gen/ldexp.3 165903 2007-01-09 00:28:16Z imp $
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35.Dd March 28, 2020
36.Dt LDEXP 3
37.Os
38.Sh NAME
39.Nm ldexp ,
40.Nm ldexpf ,
41.Nm ldexpl
42.Nd multiply floating-point number by integral power of 2
43.Sh LIBRARY
44.Lb libm
45.Sh SYNOPSIS
46.In math.h
47.Ft double
48.Fn ldexp "double x" "int exp"
49.Ft float
50.Fn ldexpf "float x" "int exp"
51.Ft long double
52.Fn ldexpl "long double x" "int exp"
53.Sh DESCRIPTION
54The
55.Fn ldexp ,
56.Fn ldexpf ,
57and
58.Fn ldexpl
59functions multiply a floating-point number by an integral
60power of 2.
61.Sh RETURN VALUES
62These functions return the value of
63.Fa x
64times 2 raised to the power
65.Fa exp .
66.Sh SEE ALSO
67.Xr frexp 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