xref: /freebsd/lib/libc/gen/frexp.3 (revision 6f1dd8edc029eead6eef0c38773fb940de48155c)
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36.\"     @(#)frexp.3	8.1 (Berkeley) 6/4/93
37.\" $FreeBSD$
38.\"
39.Dd January 23, 2005
40.Dt FREXP 3
41.Os
42.Sh NAME
43.Nm frexp
44.Nd convert floating-point number to fractional and integral components
45.Sh LIBRARY
46.Lb libm
47.Sh SYNOPSIS
48.In math.h
49.Ft double
50.Fn frexp "double value" "int *exp"
51.Ft double
52.Fn frexpf "float value" "int *exp"
53.Sh DESCRIPTION
54The
55.Fn frexp
56and
57.Fn frexpf
58functions break a floating-point number into a normalized
59fraction and an integral power of 2.
60They store the integer in the
61.Vt int
62object pointed to by
63.Fa exp .
64.Sh RETURN VALUES
65These functions return the value
66.Va x ,
67such that
68.Va x
69is a
70.Vt double
71with magnitude in the interval
72.Bo 1/2 , 1 Pc
73or zero, and
74.Fa value
75equals
76.Va x
77times 2 raised to the power
78.Fa *exp .
79If
80.Fa value
81is zero, both parts of the result are zero.
82.Sh SEE ALSO
83.Xr ldexp 3 ,
84.Xr math 3 ,
85.Xr modf 3
86.Sh STANDARDS
87The
88.Fn frexp
89and
90.Fn frexpf
91functions conform to
92.St -isoC-99 .
93