Re: Re: information on Eigensystem

*To*: mathgroup at smc.vnet.net*Subject*: [mg33618] Re: [mg33594] Re: information on Eigensystem*From*: Andrzej Kozlowski <andrzej at tuins.ac.jp>*Date*: Wed, 3 Apr 2002 18:08:25 -0500 (EST)*Sender*: owner-wri-mathgroup at wolfram.com

Which version of Mathematica are you using? After replacing i with I, I get a (very complicated) answer (Mathematica 4.1 for Mac OS X). I have not tried to check its correctness. Andrzej On Wednesday, April 3, 2002, at 08:01 PM, Bettina Hoser wrote: > Thanks you for your comment, but I have made the mistake to hand-write > the matrix, which means, that I originally used I instead of i in the > notebook, so it is not the letter. > Is there any other solution? > Best regards, > Bettina > > Andrzej Kozlowski wrote: >> The obvious answer is to replace i with I. Andrzej Kozlowski Toyama International University JAPAN http://platon.c.u-tokyo.ac.jp/andrzej/ >> On Wednesday, April 3, 2002, at 03:13 PM, Bettina wrote: >>> Hi >>> I have another question concerning Eigensystem: I try to get the >>> Eigensystem for heritian (complex) matrices. Following my test matrix >>> M={{65,3+6i,12-6i,4-2i},{3-6i,30,0,30},{12+6i,0,9,3},{4+2i,30,3,46}}. >>> But if I try to get Eigensystem[M] nothing comes up. What could be the >>> problem? I have already found out (archive) that there seem to be some >>> special effects when using Eigensystem on complex matrices, but these >>> messages dated from 1999 and 2000. Has anything changed since then? Is >>> there a way to solve my problem? >>> Thanks for help >>> Bettina >>> >>> Jens-Peer Kuska wrote: >>> >>>> Hi, >>>> >>>> the Numerical Recipes use the EISPACK code and one can't do better >>>> than to use EISPACK or the original ALGOL source for >>>> Wilinson/Reinsch. >>>> >>>> Regards >>>> Jens >>>> >>>> Borut L wrote: >>>> >>>>> Hello, >>>>> >>>>> I am doing a comparison between three methods for finding an >>>>> eigensystem of >>>>> a matrix, Numerical Recipes tqli + tred2, jacobi, and Mathematica's >>>>> Eigensystem[]. >>>>> >>>>> I would like to acquire info on which algorithm does Mathematica >>>>> have for >>>>> finding it out? What does she do in a case of a real symmetric >>>>> matrix? I am >>>>> asking it because I haven't found anything in the implementation >>>>> notes. >>>>> >>>>> Thank you for you time, >>>>> >>>>> Borut from Slovenia >>>>> >>>> >>> >>> >>> >>> > > > -- Dipl.-Phys. Bettina Hoser > Lehrstuhl für Informationsdienste und elektonische Märkte > Fakultät für Wirtschaftswissenschaften > Universität Karlsruhe (TH) > 76128 Karlsruhe > > email: bettina.hoser at em.uni.karlsruhe.de > Tel: 0721-608 8407 > Fax: 0721-608 8403 > > >