When searching sage-support, there are several threads about people complaining they cannot plot x^(1/3) or similar on the negative axis because (-1)^(1/3) is a complex number, not a real number.
The answer is to plot something like lambda x:RR(x).nth_root(3). This is not very satisfactory because this is not a symbolic function, so I can't differentiate it for example. It is also more complicated and hard to explain to beginners using Sage. So I think the question still remains: is there something like a symbolic nth_root() function? Or, alternatively, a way of evaluating the symbolic expression x^(1/3) yielding only real numbers with real input? Such functionality would certainly be desirable. Jeroen. -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
