I think that if k is a field, then k^n is a k-vector space for any nonnegative integer n, including 0. And the empty sum is equal to 0.
In the same vein, all matrices of size (m,0) and (0,n) are equal and square and have determinant 1 (empty product). Guillermo On Fri, 6 May 2022 at 12:20, Dima Pasechnik <dimp...@gmail.com> wrote: > On Fri, May 6, 2022 at 5:04 AM Tracy Hall <h.tr...@gmail.com> wrote: > > > > The following two lines crash the kernel in 9.5 but not 9.4: > > > > xx = vector(GF(2), []) > > xx * xx > > > > It works correctly (with answer 0) over other finite fields or over QQ. > > IMHO the bug is in accepting vector(..., []) as a valid object - it's > a "vector" of length 0, after all. > > Dima > > > Installation is Sagemath 9.5 in Ubuntu running under WSL for Windows; > tested also in CoCalc Sagemath 9.5 (where it crashes) and CoCalc Sagemath > 9.4 (where it correctly produces 0). > -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-support/CANnG18_7oqwpzZvNZr4S4x3P6XBkGSi4xDMJLy-svbtgZWOKRQ%40mail.gmail.com.
