Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 31 Oct 2018 16:50:43 -0700
From:      Steve Kargl <sgk@troutmask.apl.washington.edu>
To:        freebsd-docs@freebsd.org
Subject:   [PATCH] Add missing parenthesis to csqrt.3
Message-ID:  <20181031235043.GA1820@troutmask.apl.washington.edu>

next in thread | raw e-mail | index | archive | help
The patch at the end of this email adds a missing ')'.

What is concerning is this somewhat dubious sentence
in the Results section:

  The square root of 0 is +0 ± 0, where the imaginary parts
  of the input and respective result have the same sign.

csqrt((0.0,0.0)) = (0.0,0.0)
csqrt((0.0,-0.0)) = (0.0,-0.0)
csqrt((-0.0,0.0)) = (0.0,0.0)
csqrt((-0.0,-0.0)) = (0.0,-0.0)

It seems the sentence should be 

  The square root of ±0 ± 0I is +0 ± 0I, where the imaginary parts
  of the input and respective result have the same sign.


Index: csqrt.3
===================================================================
--- csqrt.3     (revision 339978)
+++ csqrt.3     (working copy)
@@ -24,7 +24,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd March 30, 2008
+.Dd October 31, 2018
 .Dt CSQRT 3
 .Os
 .Sh NAME
@@ -78,7 +78,7 @@
 .Pp
 For numbers with negative imaginary parts, the above special cases
 apply given the identity:
-.Dl csqrt(conj(z) = conj(sqrt(z))
+.Dl csqrt(conj(z)) = conj(sqrt(z))
 Note that the sign of \*(Na is indeterminate.
 Also, if the real or imaginary part of the input is finite and
 an \*(Na is generated, an invalid exception will be thrown.


-- 
Steve



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20181031235043.GA1820>