On Nov 18, 2009, at 6:25 PM, Ichnich wrote: > Hi, > > I want to find the solution of a system of coupled differential > equations. > Therfore I need the eigenvalues and vectors of a matrix D and their > complex conjugates. > short example: > sage: D=matrix([[0,1],[-1,0]]) > > sage: EV=D.eigenvectors_left();EV > [(-1*I, [(1, 1*I)], 1), (1*I, [(1, -1*I)], 1)] > > sage: EV[0][1][0] # first eigenvector > (1, 1*I) > > sage: (EV[0][1][0]).conjugate() > Traceback (most recent call last): > ... > AttributeError: 'sage.modules.free_module_element.FreeModuleElement' > object has no attribute 'conjugate' > > sage: matrix(sage_eval(repr(EV[0][1][0]))).conjugate() > [ 1 -I] > > Is there an easier way to get the result of the last row? Or is there > an easy way to cast from and to vector and matrix types?
No, unfortunately there's not a really easy way to do this. It would make sense for vectors to "inherit" some elements of their elements, or at least have a map command like matrix does. sage: matrix(EV[0][1][0]).apply_map(conjugate)[0] (1, -1*I) Alternatively, I could use list comprehension, sage: vector([a.conjugate() for a in EV[0][1][0]]) (1, -1*I) - Robert -- 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 For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
