A workaround for this case (but not a good solution in general)
(%i1) m : rationalize(matrix( [10.48273938962865,14.15187882832064],
[21.22781824248096,31.71055763210962]))$
float(eigenvectors(m));
(%o2)
[[[0.77255988699335,41.42073713474491],[1.0,1.0]],[1.0,-0.68614066163451],[1.0,
2.186140661634508]]
Barton
-----maxima-bounces at math.utexas.edu wrote: -----
>To: maxima at math.utexas.edu
>From: "Bowo Prasetyo"
>Sent by: maxima-bounces at math.utexas.edu
>Date: 04/03/2007 06:44AM
>Subject: 'eigenvectors' failed..
>
>Hi,
>
>'eigenvectors' failed to work on numeric 2x2 matrix below..
>
>m: matrix( [10.48273938962865,14.15187882832064],
>[21.22781824248096,31.71055763210962] );
>eigenvectors(m)
>
>It gave the following error message..
>
>algsys failure: the eigenvector(s) for the 1 th eigenvalue will be
>missing.
>algsys failure: the eigenvector(s) for the 2 th eigenvalue will be
>missing.
>
>and just returned the eigenvalues..
>
>[0.77255984019432, 41.42073711336268]
>
>Using another software.. the eigenvectors should be..
>
>eigenvector of eigenvalue 0.7725598869933528:
> (-0.8245648401323937, 0.5657674649689922)
>eigenvector of eigenvalue 41.42073713474491:
> (0.4159735579192842, 0.9093767091321241)
>
>Anyone knows what has happened?
>
>I noticed little difference in eigenvalues after 7-8th decimal place
>between Maxima and that another software.. maybe this caused the
>failure?
>
>Best regards,
>bowo
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