On Tuesday, December 18, 2012 11:45:47 AM UTC-8, projetmbc wrote: > > Hello, > in the following code I would like to replace x with T in Delta_X so as to > illustrate > the Cayley Hamilton theorem by doing everything by hands. > > Is it possible ? > > Best regards. > Christophe BAL > > ========================= > var('a b c d e f') > > T = matrix([ > [a, b, c], > [0, d, e], > [0, 0, f] > ]) > > T_X = T - x*identity_matrix(3) > > Delta_X = det(T_X) >
I can't get that to work. However, this does: treat the variables as polynomial indeterminates instead of symbolic variables. sage: R.<a,b,c,d,e,f,x> = QQ[] sage: T = matrix([ [a, b, c], [0, d, e], [0, 0, f] ]) sage: T_X = T - x*identity_matrix(3) sage: Delta_X = det(T_X) sage: Delta_X.subs(x=T) [0 0 0] [0 0 0] [0 0 0] -- John -- You received this message because you are subscribed to the Google Groups "sage-support" group. To post to this group, send email to sage-support@googlegroups.com. To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support?hl=en.