xref: /freebsd/lib/libc/gen/ldexp.3 (revision dc36d6f9bb1753f3808552f3afd30eda9a7b206a)
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32.Dd March 4, 2005
33.Dt LDEXP 3
34.Os
35.Sh NAME
36.Nm ldexp ,
37.Nm ldexpf ,
38.Nm ldexpl
39.Nd multiply floating-point number by integral power of 2
40.Sh LIBRARY
41.Lb libm
42.Sh SYNOPSIS
43.In math.h
44.Ft double
45.Fn ldexp "double x" "int exp"
46.Ft float
47.Fn ldexpf "float x" "int exp"
48.Ft long double
49.Fn ldexpl "long double x" "int exp"
50.Sh DESCRIPTION
51The
52.Fn ldexp ,
53.Fn ldexpf ,
54and
55.Fn ldexpl
56functions multiply a floating-point number by an integral
57power of 2.
58.Sh RETURN VALUES
59These functions return the value of
60.Fa x
61times 2 raised to the power
62.Fa exp .
63.Sh SEE ALSO
64.Xr frexp 3 ,
65.Xr math 3 ,
66.Xr modf 3
67.Sh STANDARDS
68The
69.Fn ldexp ,
70.Fn ldexpf ,
71and
72.Fn ldexpl
73functions conform to
74.St -isoC-99 .
75