Re: Q: Eigen values in Mathematica 2.2
- To: mathgroup at smc.vnet.net
- Subject: [mg4042] Re: Q: Eigen values in Mathematica 2.2
- From: ianc (Ian Collier)
- Date: Tue, 28 May 1996 01:46:53 -0400
- Organization: Wolfram Research, Inc.
- Sender: owner-wri-mathgroup at wolfram.com
In article <4noq7d$71h at dragonfly.wolfram.com>, wojtek at amedec.amg.gda.pl (Wojciech Piotrowski) wrote: > Why Mathematica 2.2 can't find Eigen values for some matrices? When I use > the earlier version ( 2.1 ) there is no problem like that. For example: > Amat={{1,2},{-2,-3}}; > Eigenvalues[Amat] > And version 2.2 displays message: can't find all roots of charactristic > polynomial, but v.2.1 answers: {-1,-1} > This no matters when I want to find only Eigen values, because I can find > it solving characteristic polynomial for instance, but Mathematica use > Eigenvalues function in JordanDecomposition which I often use. > wojtek at amedec.amg.gda.pl This appears to work correctly in the current Macintosh, Windows and Unix versions of Mathematica that I have access to: In[1]:= Eigenvalues[ {{1,2},{-2,-3}} ] Out[1]= {-1, -1} In[2]:= $Version Out[2]= Power Macintosh 2.2 (February 24, 1994) Is it possible that you have changed the definition of the Eigenvalues function? My best suggestion would be to contact Wolfram Research Technical Support (in your case support at wolfram.co.uk) directly including full details of your copy of Mathematica and also the computer you are running it on. I hope this helps. --Ian ----------------------------------------------------------- Ian Collier Wolfram Research, Inc. ----------------------------------------------------------- tel:(217) 398-0700 fax:(217) 398-0747 ianc at wolfram.com Wolfram Research Home Page: http://www.wolfram.com/ ----------------------------------------------------------- ==== [MESSAGE SEPARATOR] ====