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