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.\"     from: @(#)ieee.3	6.4 (Berkeley) 5/6/91
.\" $FreeBSD$
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.Dd May 4, 2005
.Dt NEXTAFTER 3
.Os
.Sh NAME
.Nm nextafter ,
.Nm nextafterf ,
.Nm nextafterl ,
.Nm nexttoward ,
.Nm nexttowardf ,
.Nm nexttowardl
.Nd next representable value
.Sh LIBRARY
.Lb libm
.Sh SYNOPSIS
.In math.h
.Ft double
.Fn nextafter "double x" "double y"
.Ft float
.Fn nextafterf "float x" "float y"
.Ft long double
.Fn nextafterl "long double x" "long double y"
.Ft double
.Fn nexttoward "double x" "long double y"
.Ft float
.Fn nexttowardf "float x" "long double y"
.Ft long double
.Fn nexttowardl "long double x" "long double y"
.Sh DESCRIPTION
These functions
return the next machine representable number from
.Fa x
in direction
.Fa y .
.Sh SEE ALSO
.Xr ieee 3 ,
.Xr math 3
.Sh STANDARDS
The
.Fn nextafter ,
.Fn nextafterf ,
.Fn nextafterl ,
.Fn nexttoward ,
.Fn nexttowardf ,
and
.Fn nexttowardl
routines conform to
.St -isoC-99 .
They implement the Nextafter function recommended by
.St -ieee754 ,
with the extension that
.Fn nextafter +0.0, -0.0
returns
.Li -0.0 ,
and
.Fn nextafter -0.0, +0.0
returns
.Li +0.0 .
.Sh HISTORY
The
.Fn nextafter
function appeared in
.Bx 4.3 ,
and
.Fn nextafterf
appeared in
.Fx 2.0 .