Re: What to do in v. 6 in place of Miscellaneous`RealOnly
- To: mathgroup at smc.vnet.net
- Subject: [mg76624] Re: What to do in v. 6 in place of Miscellaneous`RealOnly
- From: "David W.Cantrell" <DWCantrell at sigmaxi.net>
- Date: Fri, 25 May 2007 06:20:23 -0400 (EDT)
- References: <f33ork$l7l$1@smc.vnet.net>
Helen Read <read at math.uvm.edu> wrote:
> Suppose my calculus students want to plot x^(1/3), for say {x,-8,8}. The
> problem, of course, is that Mathematica returns complex roots for x<0.
> In past versions of Mathematica, we could get the desired real roots
> (and plot the function) by loading the package Miscellaneous`RealOnly. I
> guess we can still do it that way (and ignore the "obsolete package"
> message), but is there a suggested way of doing what we need in 6.0?
Perhaps have them define their own
realCubeRoot[x_]:= Sign[x] Abs[x]^(1/3)
which plots as desired, of course.
David