Nice Integer Eigenvectors

[Mmmm]

(03-31-2015 12:55 PM)Han Wrote:  The command eigenvects() -- in lower case -- gives the eigenvectors in rational form and works for larger sized matrices. You could probably write a simpler function that then converts rational vectors to a parallel integer vector (and apply gcd for smaller integers).

WOW! That is a great improvement over the ole EIGENVV, why didn't anyone tell me about this command?

But unfortunately it falls short - it seems to ignore repeated eigenvalues.
eg.

running it on

5|-4|0
1|0|2
0|2|5

gives only one eigenvector (-4,-5,2) which corresponds to the eigenvalue 0. There are also two more eigenvalues: 5 and 5 for which there is one more eigenvector.

My program gives (2,0,-1) as well as (4,5,-2).

I've tried it on some other matrices with repeated eigenvalues too and it always ignores them!!

Shame...