Re: Sorting Eigenvalues/EigenVectors
- To: mathgroup at smc.vnet.net
- Subject: [mg8237] Re: Sorting Eigenvalues/EigenVectors
- From: crose at c2.telstra-mm.net.au (Colin Rose)
- Date: Thu, 21 Aug 1997 21:16:54 -0400
- Organization: Theoretical Research Institute
- Sender: owner-wri-mathgroup at wolfram.com
murray at math.umass.edu (Murray Eisenberg) wrote:
> Here's one way -- undoubtedly the most elegant.
> a = {{16,19,1},{18,10,20},{10,5,3}};
> esys = N[Eigensystem[a]]
> evals = esys[[1]]; evect = esys[[2]]
> (* Sort[evals] gives the sorted list. That's not all you want. *)
> where = Flatten[Map[Position[Sort[evals], #]&, evals]]
> evals[[where]]
> evects[[where]]
Yuck.
--
Colin Rose
tr(I) - Theoretical Research Institute
______________________________________
crose at c2.telstra-mm.net.au
http://www.usyd.edu.au/su/tri/