Thanks for the patch; great job. I've moved the 0 examples to a TESTS section.
--William On 6/2/07, Michel <[EMAIL PROTECTED]> wrote: > > Here is a patch that fixes this. Perhaps there is a better way to do > it. > > http://emis.uhasselt.be/sage_patches/zero_matrix_echelon_form_bug.patch > > Michel > > > On Jun 2, 10:01 am, Michel <[EMAIL PROTECTED]> wrote: > > Ok I understand!! > > > > I just did the exercise in the pari console. > > > > ? A=[0,0,0; 0,0,0; 0,0,0] > > %3 = > > [0 0 0] > > > > [0 0 0] > > > > [0 0 0] > > > > ? mathnf(A) > > %4 = [;] > > > > So pari is a bit brain damaged and represents the empty matrix by > > [;]!!! > > This should be special cased in the parsing routines. > > > > William: I assume it is now trivial for you to correct this. If not > > then > > I will make a patch. > > > > Michel > > > > On Jun 2, 9:54 am, Michel <[EMAIL PROTECTED]> wrote: > > > > > It's quite confusing where this bug lies. I would assume that > > > > > sage.libs.pari.gen.gen.mathnf > > > > > returns the wrong thing but since I can't find the definition > > > of new_gen I can't debug it further. > > > > > Michel > > > > > On Jun 1, 10:55 pm, Michel <[EMAIL PROTECTED]> wrote: > > > > > > No patch but I can tell you were there is something obviously wrong. > > > > > > The matrix H on line 1056 in matrix_integer_dense.pyx should > > > > be the empty matrix (perhaps []?) but it is something like ['','']. > > > > The computation > > > > for adding the missing zero rows goes wrong after that. > > > > > > Michel > > > > > > On Jun 1, 9:34 pm, "William Stein" <[EMAIL PROTECTED]> wrote: > > > > > > > On 6/1/07, Thea Gegenberg <[EMAIL PROTECTED]> wrote: > > > > > > > > The method echelon_form gives me an error when I try to take the > > > > > > echelon form of a zero matrix. It says "TypeError: entries has the > > > > > > wrong length" > > > > > > > Here's an example to illustrate the bug. I hope somebody will > > > > > fix it and send me a patch :-). > > > > > > > sage: m = matrix(ZZ,3,3,[0]*9) > > > > > sage: m.ech > > > > > m.echelon_form m.echelonize > > > > > sage: m.echelon() > > > > > --------------------------------------------------------------------------- > > > > > <type 'exceptions.AttributeError'> Traceback (most recent call > > > > > last) > > > > > > > /home/was/talks/2007-06-01-grants/<ipython console> in <module>() > > > > > > > <type 'exceptions.AttributeError'>: > > > > > 'sage.matrix.matrix_integer_dense.Matrix_integer_de' object has no > > > > > attribute 'echelon' > > > > > sage: m.echelon_form() > > > > > --------------------------------------------------------------------------- > > > > > <type 'exceptions.TypeError'> > > > > > -- William Stein Associate Professor of Mathematics University of Washington http://www.williamstein.org --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://sage.math.washington.edu/sage/ and http://sage.scipy.org/sage/ -~----------~----~----~----~------~----~------~--~---
