xref: /freebsd/lib/msun/man/remainder.3 (revision 29bf6af8904f9833bbc9c0e5f2219f785defe550)
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32.\"     from: @(#)ieee.3	6.4 (Berkeley) 5/6/91
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35.Dd January 26, 2005
36.Dt REMAINDER 3
37.Os
38.Sh NAME
39.Nm remainder ,
40.Nm remainderf
41.Nd minimal residue functions
42.Sh LIBRARY
43.Lb libm
44.Sh SYNOPSIS
45.In math.h
46.Ft double
47.Fn remainder "double x" "double y"
48.Ft float
49.Fn remainderf "float x" "float y"
50.Sh DESCRIPTION
51.Fn remainder
52and
53.Fn remainderf
54return the remainder
55.Fa r
56:=
57.Fa x
58\-
59.Fa n\(**y
60where
61.Fa n
62is the integer nearest the exact value of
63.Bk -words
64.Fa x Ns / Ns Fa y ;
65.Ek
66moreover if
67.Pf \\*(Ba Fa n
68\-
69.Sm off
70.Fa x No / Fa y No \\*(Ba
71.Sm on
72=
731/2
74then
75.Fa n
76is even.
77Consequently
78the remainder is computed exactly and
79.Sm off
80.Pf \\*(Ba Fa r No \\*(Ba
81.Sm on
82\*(Le
83.Sm off
84.Pf \\*(Ba Fa y No \\*(Ba/2 .
85.Sm on
86But
87.Fn remainder x 0
88and
89.Fn remainder \*(If 0
90are invalid operations that produce a \*(Na.
91.Sh SEE ALSO
92.Xr fmod 3 ,
93.Xr ieee 3 ,
94.Xr math 3
95.Sh STANDARDS
96The
97.Fn remainder
98and
99.Fn remainderf
100routines conform to
101.St -isoC-99
102and
103.St -ieee754 .
104.Sh HISTORY
105The
106.Fn remainder
107and
108.Fn remainderf
109functions appeared in
110.Bx 4.3
111and
112.Fx 2.0 ,
113respectively.
114