forum.alglib.net

Hi,

I am using rmatrixevd to compute the eigenvalues and eigenvectors of a non-symmetric real matrix in C#. The code computes the eigenvalues correctly but when it comes to the eigenvectors, I am lost. These may be completely stupid and obvious questions but I have been working on this for few days and am not making any progress.

I have three issues:

1. The results I obtain are very different from those I get using an online calculator.
http://www.arndt-bruenner.de/mathe/scripts/engl_eigenwert.htm

2. The online calculator allows you to change the "norming mode" whereas rmatrixevd does not. What is the "norming mode" used in rmatrixevd.

3. For a test case I use a 4x4 matrix. As two of my eigenvalues are complex, and two are real, how do I extract the correct left and right eigenvectors corresponding to all my eigenvalues?

My test matrix is

2 9 0 2
-1 2 1 0
0 0 3 0
0 0 1 -1

Any help would be greatly appreciated. Thank you very much.