sage: R.<a> = PolynomialRing(QQ,"a") sage: A=matrix([[0,1,1],[2,2,-2],[-1,a,3]]) sage: A.echelon_form()
[ 2 2 -2] [ 0 -1 -1] [ 0 0 -a + 1] On Thu, Oct 15, 2009 at 10:45 PM, Matt Rissler <[email protected]> wrote: > > Basically, I'm having student look for the x that makes the matrix > singular, or the columns linearly dependent, or ... However Sage > behaves like so: > > sage: A=matrix([[0,1,1],[2,2,-2],[-1,x,3]]) > sage: A > [ 0 1 1] > [ 2 2 -2] > [-1 x 3] > sage: A.echelon_form() > [1 0 0] > [0 1 0] > [0 0 1] > > > Is there anyway to make it so Sage doesn't assume that it can rescale > by dividing by whatever function of x we get in the bottom row (in > this case 1-x), because that might be 0? > > Doing the row reduction 'by hand', ie making Sage do it, works, but it > would be nice if echelon form did it. > > Thanks, > > Matt > > > --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
