Re: Plot Question
- To: mathgroup at smc.vnet.net
- Subject: [mg6847] Re: [mg6797] Plot Question
- From: jpk at max.mpae.gwdg.de
- Date: Thu, 24 Apr 1997 02:44:28 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
> Folks,
>
>
> It has been a long time since I plotted anything on the MMA program.
>
> I would however like to know why this is not plotting correctly, The
> math for this is completely sound by the way.
>
>
> I want to have MMA plot the following:
>
> Plot[{-x^3, -x^(1/3), x}, {x, -10, 10}]
>
> I get the following errors for this:
> Plot::plnr : -x^(1/3) is not a machine-size number at x = -10
> " " " " " " " " " " " x = -9.18866
> " " " " " " " " " " " x = -8.30382
>
>
> I have tried to expand the restrict values to no end. Any information
> would be helpful in this matter.
>
> Note the the following does graph correctly:
> -x^3
> x
> and only part of the graph for the third.
>
>
> Do not understand why it is doing this
> please send information to email address listed below I will get it
> faster
>
>
>
> Thanks for any help in this!!
>
>
>
>
>
> Sincerely,
>
>
>
>
> Ivan G. Burch II aka enforcer
> at email address:
> "ivanb at hula.net"
>
Hi Ivan,
x^(1/3) has several solutions for x<0 and You have to decide which root
You want -- look for the (Mathematica 3.0 standard package)
Miscellaneous`RealOnly` that will solve Your problem.
Hope that helps
Jens