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34.Dd $Mdocdate: June 5 2013 $
35.Dt FREXP 3
36.Os
37.Sh NAME
38.Nm frexp ,
39.Nm frexpf ,
40.Nm frexpl
41.Nd convert floating-point number to fractional and integral components
42.Sh SYNOPSIS
43.In math.h
44.Ft double
45.Fn frexp "double value" "int *exp"
46.Ft float
47.Fn frexpf "float value" "int *exp"
48.Ft long double
49.Fn frexpl "long double value" "int *exp"
50.Sh DESCRIPTION
51The
52.Fn frexp
53function breaks a floating-point number into a normalized
54fraction and an integral power of 2.
55It stores the integer in the
56.Li int
57object pointed to by
58.Fa exp .
59The
60.Fn frexpf
61function is a single precision version of
62.Fn frexp .
63The
64.Fn frexpl
65function is an extended precision version of
66.Fn frexp .
67.Sh RETURN VALUES
68The
69.Fn frexp ,
70.Fn frexpf
71and
72.Fn frexpl
73functions return the value
74.Li x ,
75such that
76.Li x
77is a
78.Li double
79with magnitude in the interval [1/2,\ 1) or zero, and
80.Fa value
81equals
82.Li x
83times 2 raised to the power
84.Fa *exp .
85If
86.Fa value
87is zero, both parts of the result are zero.
88.Sh SEE ALSO
89.Xr ldexp 3 ,
90.Xr modf 3
91.Sh STANDARDS
92The
93.Fn frexp
94function conforms to
95.St -ansiC .
96