If the multiplication sign * is absent ( say by mistake!) what is SAGE evaluating? For example: x=var('x');f=1/((x-1)(x-3)); f.limit(x=1) returns -1/3 diff(f,x) returns -1/(x - 4)^2 plot(f,(x,0,10)) plots a smooth curve going through -1/3.
It is clear it is evaluating f =1/(x-4). How? Why is not pointing to the possible error? Of course with x=var('x');f=1/((x-1)*(x-3)); diff(f,x) returns -1/((x - 3)*(x - 1)^2) - 1/((x - 3)^2*(x - 1)) f.limit(x=1) returns +Infinity etc. -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org