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Eigensystem

• To: mathgroup at yoda.physics.unc.edu
• Subject: Eigensystem
• From: billl at helmholtz.sdsc.edu (Bill Lytton)
• Date: Fri, 19 Jun 92 15:11:55 PDT

My report of a discrepancy between Eigensystem and Eigenvalues was wrong.
My error was in trying to equate the results of symbolic and numerical
calculations.  They differed in the arbitrary order given to the roots
of the characteristic eqn.  Therefore:

aa = {{-a1, b1,0},{a1,-(b1+a2),b2},{0,a2,-b2}}

bb = aa /. {a1->5.,b1->1.,a2->4.,b2->15.}

Eigenvalues[aa] /. {a1->5.,b1->1.,a2->4.,b2->15.} != Chop[Eigenvalues[bb]]

 -Bill