1.\" Copyright (c) 2004 David Schultz <das@FreeBSD.org>
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25.\" $FreeBSD: src/lib/msun/man/fdim.3,v 1.1 2004/06/30 07:04:01 das Exp $
26.\" $NetBSD$
27.\"
28.Dd $Mdocdate: February 9 2014 $
29.Dt FDIM 3
30.Os
31.Sh NAME
32.Nm fdim ,
33.Nm fdimf
34.Nd positive difference functions
35.Sh LIBRARY
36.Lb libm
37.Sh SYNOPSIS
38.In math.h
39.Ft double
40.Fn fdim "double x" "double y"
41.Ft float
42.Fn fdimf "float x" "float y"
43.Sh DESCRIPTION
44The
45.Fn fdim
46and
47.Fn fdimf
48functions return the positive difference between
49.Fa x
50and
51.Fa y .
52That is, if
53.Fa x\- Ns Fa y
54is positive, then
55.Fa x\- Ns Fa y
56is returned.
57If either
58.Fa x
59or
60.Fa y
61is an \*(Na, then an \*(Na is returned.
62Otherwise, the result is
63.Li +0.0 .
64.Pp
65Overflow or underflow may occur iff the exact result is not
66representable in the return type.
67No other exceptions are raised.
68.Sh SEE ALSO
69.Xr fabs 3 ,
70.Xr fmax 3 ,
71.Xr fmin 3 ,
72.Xr math 3
73.Sh STANDARDS
74The
75.Fn fdim
76and
77.Fn fdimf
78functions conform to
79.St -isoC-99 .
80.Sh HISTORY
81These routines first appeared in
82.Fx 5.3
83and
84.Nx 5.1 .
85