Re: What to do in v. 6 in place of Miscellaneous`RealOnly

*To*: mathgroup at smc.vnet.net*Subject*: [mg76678] Re: What to do in v. 6 in place of Miscellaneous`RealOnly*From*: dimitris <dimmechan at yahoo.com>*Date*: Fri, 25 May 2007 06:48:35 -0400 (EDT)*References*: <f33ork$l7l$1@smc.vnet.net>

Hi Helen. I don't have version 6 but in case you don't know there is a much more flexible package named SwitchableRealOnly by Ted Ersek available at http://library.wolfram.com/infocenter/MathSource/560/ Also if you want to avoid the use of any package you can let your students defining their own "always real cubic root". In[16]:= RealCubicRoot[x_] := Sign[x]*Abs[x]^(1/3) In[17]:= Plot[RealCubicRoot[x], {x, -2, 2}] Dimitris / Helen Read : > 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? > > -- > Helen Read > University of Vermont