On Fri, Mar 6, 2015 at 5:10 PM, P Purkayastha <ppu...@gmail.com> wrote: > > > On Saturday, March 7, 2015 at 6:48:46 AM UTC+8, Michael Orlitzky wrote: >> >> On 03/06/2015 04:51 PM, Travis Scrimshaw wrote: >> > Yet this stopgap is not in a class in the global namespace, but a >> > low-level class that almost always gets passed valid input. I am for >> > having >> > checks for valid input (and most of the time it does error out), but >> > there >> > is only one place I know of in the global namespace that can get invalid >> > input ( Partitions(k, max_slope=m) with m >= 0 ). We have *years* of >> > testing code which does pass valid input into IntegerListsLex that gives >> > correct results (and it sometimes works on invalid input as well). >> > >> > Here are some tickets where Sage silently returns invalid results (from >> > 2 >> > minutes of looking through the bugs): >> > >> >> This might be the first bug I ever reported: >> >> sage: m = matrix([ [(-3/10), (1/5), (1/10)], >> ....: [(1/5), (-2/5), (2/5)], >> ....: [(1/10), (1/5), (-1/2)] ]) >> sage: >> sage: n = matrix([ [-0.3, 0.2, 0.1], >> ....: [0.2, -0.4, 0.4], >> ....: [0.1, 0.2, -0.5] ]) >> sage: >> sage: m.rank() >> 2 >> sage: n.rank() >> 3 >> sage: m == n >> True >> > > This is a serious bug. Is there a ticket for this?
I don't consider this a bug. Rank is not a very meaningful for matrices with floating point entries. -- William -- William (http://wstein.org) -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.