multivariate polynomials



Hi Paolo
you may load eigen package,like
(C1) load("eigen")$
(C2) display2d:false $
(C3) H:matrix([_a,v,0],[v,b,0],[0,v,c])$
(C4) eigenvalues(H);
(D5) [[(-SQRT(_a^2-2*b*_a+4*v^2+b^2)+_a+b)/2,
     (SQRT(_a^2-2*b*_a+4*v^2+b^2)+_a+b)/2,c],[1,1,1]]
please down load diag.mac and jordan.dem from
cvsroot/maxima/share/contrib

(C6) load("diag.mac")$
(C7) jordan(H);

(D7) [[(-SQRT(_a^2-2*b*_a+4*v^2+b^2)+_a+b)/2,1],
       [(SQRT(_a^2-2*b*_a+4*v^2+b^2)+_a+b)/2,1],[c,1]]
(C8) displayJordan(%);

(D9) MATRIX([(-SQRT(_a^2-2*b*_a+4*v^2+b^2)+_a+b)/2,0,0],
            [0,(SQRT(_a^2-2*b*_a+4*v^2+b^2)+_a+b)/2,0],[0,0,c])


Gosei Furuya 

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Hi,

i am trying to perform diagonalization of a 3x3 matrix, of the form:


     [ e1,  V,  0  ] 
H := [  V, e2,  V ]
     [  0,  V, e3 ] 


which gives rise to a multivariate characteristic polynomial, that  Maxima
fails to compute (here enclosed is the log file).
I wonder is there is a trick to get the work done.


Thank you 

--
Paolo Pumilia