xref: /freebsd/lib/libc/gen/modf.3 (revision 640235e2c2ba32947f7c59d168437ffa1280f1e6)
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32.\"     @(#)modf.3	8.1 (Berkeley) 6/4/93
33.\" $FreeBSD$
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35.Dd March 29, 2008
36.Dt MODF 3
37.Os
38.Sh NAME
39.Nm modf ,
40.Nm modff ,
41.Nm modfl
42.Nd extract signed integral and fractional values from floating-point number
43.Sh LIBRARY
44.Lb libm
45.Sh SYNOPSIS
46.In math.h
47.Ft double
48.Fn modf "double value" "double *iptr"
49.Ft float
50.Fn modff "float value" "float *iptr"
51.Ft long double
52.Fn modfl "long double value" "long double *iptr"
53.Sh DESCRIPTION
54The
55.Fn modf ,
56.Fn modff ,
57and
58.Fn modfl
59functions break the argument
60.Fa value
61into integral and fractional parts, each of which has the
62same sign as the argument.
63It stores the integral part as a
64floating point number
65in the object pointed to by
66.Fa iptr .
67.Sh RETURN VALUES
68These functions return the signed fractional part of
69.Fa value .
70.Sh SEE ALSO
71.Xr frexp 3 ,
72.Xr ldexp 3 ,
73.Xr math 3
74.Sh STANDARDS
75The
76.Fn modf ,
77.Fn modff ,
78and
79.Fn modfl
80functions conform to
81.St -isoC-99 .
82