🚀 go-pugleaf

RetroBBS NetNews Server

Inspired by RockSolid Light RIP Retro Guy

Article View: sci.math.num-analysis
Article #1193

Re: Sure Polynomial Roots

#1193
From: Peter Pan
Date: Fri, 06 Aug 2004 00:10
37 lines
2491 bytes
brianscsmith@yahoo.com (Brian Smith) wrote 
> 
> I see that you are no longer claiming to have solved the general
> polynomial equation, now its just a numeric formula.  Why should I
> even consider this method for approximating roots when Newton's
> iteration only needs the first derivative and only a few iterations
> are needed to get the three place precesion that your method provides
> in the example.  I see no need to calculate dozens of terms when it is
> so much simpler to let Newton's iteration run for more cycles.


AND ... 

Jon's method calculates the solution of x - 1 = 0 as 0.7 ...
(ridiculous)

AND ...

the examples he gives on his website are NOT correctly calculated

AND

where is the notorious 'high degree of accuracy and precision' 

as I said before: PLAIN BULLSHIT !!!


Hint: Use Newton's method, refined by Householder:

                       (1/p)k             
x_(n+1)=x_n + (k+1)*------------(x_n)
                      (1/p)(k+1)
[the 'k' and 'k+1' at the (1/p)'s intends to mean k-th resp. (k+1)-th
derivative]
 
to obtain an approximation of real roots at an order of k+2 (iff you
have an appropriate starting value)
Technical Details
Message-ID: <3cc72195.0408051610.58e54b2c@posting.google.com>
Path: arc1-ca.pugleaf.net!g2news1.google.com!postnews2.google.com!not-for-mail
References: <4111D4FB.8050608@peoplepc.com> <12f59340.0408050442.77cdea79@posting.google.com>

Show Full Headers
Complete Article Headers
X-Google-Thread: 107079,dfd14b9e0d1043ac
X-Google-Thread: 109d8a,dfd14b9e0d1043ac
X-Google-Thread: f72df,dfd14b9e0d1043ac
X-Google-Thread: 103471,dfd14b9e0d1043ac
X-Google-Thread: 1139f8,dfd14b9e0d1043ac
X-Google-Thread: 10d67e,dfd14b9e0d1043ac
X-Google-Thread: 1130d6,dfd14b9e0d1043ac
X-Google-Thread: f6df2,dfd14b9e0d1043ac
X-Google-Attributes: gid107079,gid109d8a,gidf72df,gid103471,gid1139f8,gid10d67e,gid1130d6,gidf6df2,public
X-Google-Language: ENGLISH,ASCII-7-bit
Path: arc1-ca.pugleaf.net!g2news1.google.com!postnews2.google.com!not-for-mail
From: RMoebs1@compuserve.de (Peter Pan)
Newsgroups: sci.math.num-analysis,sci.math,japan.sci.math,han.sci.math,fr.sci.maths,aus.mathematics,alt.math.recreational,bln.sci.mathematik
Subject: Re: Sure Polynomial Roots
Date: 5 Aug 2004 17:10:56 -0700
Organization: http://groups.google.com
Lines: 37
Message-ID: <3cc72195.0408051610.58e54b2c@posting.google.com>
References: <4111D4FB.8050608@peoplepc.com> <12f59340.0408050442.77cdea79@posting.google.com>
NNTP-Posting-Host: 84.129.104.53
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 8bit
X-Trace: posting.google.com 1091751056 12980 127.0.0.1 (6 Aug 2004 00:10:56 GMT)
X-Complaints-To: groups-abuse@google.com
NNTP-Posting-Date: Fri, 6 Aug 2004 00:10:56 +0000 (UTC)