xref: /freebsd/lib/libc/gen/ldexp.3 (revision 911f0260390e18cf85f3dbf2c719b593efdc1e3c)
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32.\"     @(#)ldexp.3	8.2 (Berkeley) 4/19/94
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35.Dd March 4, 2005
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 math 3 ,
69.Xr modf 3
70.Sh STANDARDS
71The
72.Fn ldexp ,
73.Fn ldexpf ,
74and
75.Fn ldexpl
76functions conform to
77.St -isoC-99 .
78