Le 08/01/2013 17:50, Andrey Novoseltsev a écrit :
So, what should x*(y > 0) do, raise a NotImplementedError? And x*(y == 0)? I guess we just special case inequalities.
I hit my students with a cluebat (though only metaphorically... [giant sigh]) when they multiply an inequality without assumption on the factor, so I would say either we know something about the sign of x (three possible signs: 0, <0 and >0) and act accordingly or raise an exception, perhaps ArithmeticError.
For the equality, there's no problem. Snark on #sagemath -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To post to this group, send email to sage-devel@googlegroups.com. To unsubscribe from this group, send email to sage-devel+unsubscr...@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel?hl=en.