 
 
 
 
 
 
Re: Plot3D?
- To: mathgroup at smc.vnet.net
- Subject: [mg34048] Re: Plot3D?
- From: "Allan Hayes" <hay at haystack.demon.co.uk>
- Date: Sun, 28 Apr 2002 03:46:43 -0400 (EDT)
- References: <aadbmd$qrd$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Plot3D will only plot one surface over a rectangular region, it store only
matrix of heights.
Four solutions:
1) Plot separately,  DisplayFunction\[Rule]Identity turns of the display.
    g1 = Plot3D[x + y, {x, -5, 5}, {y, -5, 5},
        DisplayFunction -> Identity];
    g2 = Plot3D[x^2 + y^2, {x, -5, 5}, {y, -5, 5},
        DisplayFunction -> Identity];
Show them together, DisplayFunction\[Rule]$DisplayFunction turns the display
back on]
    Show[g1, g2, DisplayFunction -> $DisplayFunction]
2) Use Block to temporarity disable display:
    Show[Block[{$DisplayFunction = Identity},
       {Plot3D[x + y, {x, -5, 5}, {y, -5, 5}],
        Plot3D[x^2 + y^2, {x, -5, 5}, {y, -5, 5}]}]]
3) Load a standard package
    << "Graphics`Graphics`"
Now we can use
    DisplayTogether[Plot3D[x + y, {x, -5, 5}, {y, -5, 5}],
      Plot3D[x^2 + y^2, {x, -5, 5}, {y, -5, 5}]]
4) use ParametricPlot3D and adjust shape of bounding box.
    ParametricPlot3D[{{x, y, x + y}, {x, y, x^2 + y^2}},
      {x, -5, 5}, {y, -5, 5}, BoxRatios -> {1, 1, 0.4}]
--
Allan
---------------------
Allan Hayes
Mathematica Training and Consulting
Leicester UK
www.haystack.demon.co.uk
hay at haystack.demon.co.uk
Voice: +44 (0)116 271 4198
Fax: +44 (0)870 164 0565
"Rex_chaos" <rex_chaos at 21cn.com> wrote in message
news:aadbmd$qrd$1 at smc.vnet.net...
> Hello all,
> I want to plot 2 3D graph in a same figure. However, the following
> instruction report error:
>   Plot3D[List[x + y, x^2 + y^2], {x, -5, 5}, {y, -5, 5}]
>
> How can I do that?
>
> Thanks
>

