diff options
Diffstat (limited to 'lib/libm/common_source/sqrt.3')
-rw-r--r-- | lib/libm/common_source/sqrt.3 | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/lib/libm/common_source/sqrt.3 b/lib/libm/common_source/sqrt.3 new file mode 100644 index 0000000..067a70e --- /dev/null +++ b/lib/libm/common_source/sqrt.3 @@ -0,0 +1,121 @@ +.\" Copyright (c) 1985, 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)sqrt.3 8.1 (Berkeley) 6/4/93 +.\" $FreeBSD$ +.\" +.Dd June 4, 1993 +.Dt SQRT 3 +.Os +.Sh NAME +.Nm cbrt , +.Nm sqrt +.Nd cube root and square root functions +.Sh SYNOPSIS +.Fd #include <math.h> +.Ft double +.Fn cbrt "double x" +.Ft double +.Fn sqrt "double x" +.Sh DESCRIPTION +The +.Fn cbrt +function computes +the cube root of +.Ar x . +.Pp +The +.Fn sqrt +computes the +non-negative square root of x. +.Sh RETURN VALUES +The +.Fn cbrt +function returns the requested cube root. +The +.Fn sqrt +function returns the requested square root +unless an error occurs. +On the +.Tn VAX +or +.Tn Tahoe +processor an attempt to take the +.Fn sqrt +of negative +.Fa x +causes an error; in this event, +the global variable +.Va errno +is set to +.Dv EDOM +and a reserved operand fault is generated. +.Sh ERROR (due to Roundoff etc.) +The +.Fn cbrt +function +is accurate to within 0.7 +.Em ulps . +.Pp +The +.Fn sqrt +function on a +.Tn VAX +is accurate to within 0.501 +.Em ulps . +Sqrt on a machine that conforms to +.Tn IEEE +754 is correctly rounded +in accordance with the rounding mode in force; the error is less than +half an +.Em ulp +in the default mode (round\-to\-nearest). +An +.Em ulp +is one +.Em U Ns nit +in the +.Em L Ns ast +.Em P Ns lace +carried. +.Sh SEE ALSO +.Xr infnan 3 , +.Xr math 3 +.Sh STANDARDS +The +.Nm sqrt +function conforms to +.St -ansiC . +.Sh HISTORY +The +.Nm cbrt +function appeared in +.Bx 4.3 . |