Re: Plot3D help please
- To: mathgroup at smc.vnet.net
- Subject: [mg68212] Re: Plot3D help please
- From: Peter Pein <petsie at dordos.net>
- Date: Sat, 29 Jul 2006 01:00:45 -0400 (EDT)
- References: <eaa21v$nd4$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
1156 schrieb:
> Hi, I'd like to use Plot3D where the range of two independent variables
> interact. That is, in the example below I'd like to specify the range of
> td and have the other variable's range be dependent upon td. All this
> because the variable tw must always be less or equal to td for the
> function rh to make sense. rh has been previously defined in terms of td
> and tw.
>
> Plot3D[rh, {td, 20, 30}, {tw, td - 5, td}]
>
> I would appreciate any tips on how to pull this off.
>
Hi 34²,
rh = (tw*td)/(6 + tw - td); (* example *)
Plot3D[rh, {td, 20, 30}, {tw, 15, 30}] (* plot contains singularities *)
Off[Plot3D::plnc, Plot3D::gval]
Plot3D[Piecewise[{{rh, tw >= td - 5}}, "foo"], {td, 20, 30}, {tw, 15, 30}]
is not nice, but:
<< "Smooth3D`"
(* http://forums.wolfram.com/mathgroup/archive/2000/Apr/msg00239.html *)
Off[Graphics3D::nlist3]
Smooth3D[Plot3D[Piecewise[{{rh, tw >= td - 5}}, "foo"], {td, 20, 30}, {tw, 15, 30},
PlotPoints -> 65], Smoothing -> 4]
looks better.
HTH,
Peter