Opened 15 years ago

Closed 14 years ago

#182 closed bug (fixed)

Bareiss buggy?

Reported by: Viktor Levandovskyy Owned by: seelisch
Priority: minor Milestone: 3-1-1
Component: singular-kernel Version: 3-1-0
Keywords: Bareiss Cc:

Description

ring r = integer, w, lp; matrix c[3][3] = [-w2+1,-w2+3w-2,0,-w2+3w-2,3w-3,0,w2-4,w2-3w+2,-3w+6]; "det:"; det(c); yields correct result ""; "minor:"; minor(c,3); yields wrong result

Change History (2)

comment:1 Changed 15 years ago by seelisch

new experimental implementation in branch SINGULAR_for_minors works for the above given example, moreover, it already

  • implements Laplace (naive),
  • Laplace (no so naive, i.e., with cache),
  • Bareiss (with minimal number of operations, whereas old code performs too many).

To Do: Furthermore include in new implementation:

  • computation of just the first k (k >0) non-zero minors,
  • loop over all non-zero minors,
  • reduction of all minors with respect to a given standard basis
  • build/adjust SINGULAR command(s) accordingly (afterwards using new code)
  • as part of last item: implement heuristics for a generic user command,
  • documentation

comment:2 Changed 14 years ago by seelisch

Resolution: fixed
Status: newclosed

will be fixed in next minor release

Note: See TracTickets for help on using tickets.