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 Author Comment/Response Giorgio 04/18/02 2:27pm I want to calculate the eigenvectors of the square matrix m={{k1/I1,-k1/I1},{(-I3k1+I1k2)/(I2 I3),(I2k2+I3(k1+k2))/(I2I3)}} If now I want to evaluate the matrix for the case I1=I2=I3 and k1=k2 and then calculate the eigenvectors, that is Eigenvectors[m/.I{2->I1,I3->I1,k2->k1}] I obtain the correct result {{1,0},{0.5,-1}}. If on the other side I calculate Eigenvectors[m]/.{I2->I1,I3->I1,k2->k1} I obtain an error of infinite value. In fact Eigenvectors[m] contains a denominator with the polynomial -I1^2k1 +Sqrt[I1^4 k1^2] that goes to zero if simplified. Does anyone know the reason for this? Is it due to the way Mathematica treates variables? How can I obtain an expression of the eigenvectors that is not affected by this problem? Thanks in advance Giorgio URL: ,

 Subject (listing for 'Eigenvectors and substitutions') Author Date Posted Eigenvectors and substitutions Giorgio 04/18/02 2:27pm Re: Eigenvectors and substitutions Henry Lamb 04/24/02 03:42am Re: Eigenvectors and substitutions Giorgio 04/25/02 11:16am
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