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[dragonfly.git] / lib / libc / gen / ldexp.3
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36.\" @(#)ldexp.3 8.2 (Berkeley) 4/19/94
37.\" $FreeBSD: src/lib/libc/gen/ldexp.3,v 1.5.2.3 2001/12/14 18:33:51 ru Exp $
1de703da 38.\" $DragonFly: src/lib/libc/gen/ldexp.3,v 1.2 2003/06/17 04:26:42 dillon Exp $
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39.\"
40.Dd April 19, 1994
41.Dt LDEXP 3
42.Os
43.Sh NAME
44.Nm ldexp
45.Nd multiply floating-point number by integral power of 2
46.Sh LIBRARY
47.Lb libc
48.Sh SYNOPSIS
49.In math.h
50.Ft double
51.Fn ldexp "double x" "int exp"
52.Sh DESCRIPTION
53The
54.Fn ldexp
55function multiplies a floating-point number by an integral
56power of 2.
57.Sh RETURN VALUES
58The
59.Fn ldexp
60function returns the value of
61.Fa x
62times 2 raised to the power
63.Fa exp .
64.Pp
65If the resultant value would cause an overflow,
66the global variable
67.Va errno
68is set to
69.Er ERANGE
70and the value
71.Dv HUGE
72is returned.
73.Sh SEE ALSO
74.Xr frexp 3 ,
75.Xr math 3 ,
76.Xr modf 3
77.Sh STANDARDS
78The
79.Fn ldexp
80function conforms to
81.St -isoC .