Mon, 11 Jan 2010 11:47:38 +0100 Matrices form a semiring with 0
hoelzl [Mon, 11 Jan 2010 11:47:38 +0100] rev 34872
Matrices form a semiring with 0
(0) -30000 -10000 -3000 -1000 -300 -100 -30 -10 -1 +1 +10 +30 +100 +300 +1000 +3000 +10000 +30000 tip