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'> --~--~---------~--~----~------------~-------~--~----~ 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/ -~----------~----~----~----~------~----~------~--~---
