Re: Derivative of a funtion evaluated at a point in 3D
- To: mathgroup at smc.vnet.net
- Subject: [mg44490] Re: Derivative of a funtion evaluated at a point in 3D
- From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
- Date: Wed, 12 Nov 2003 08:01:38 -0500 (EST)
- Organization: Universitaet Leipzig
- References: <boign7$oj1$1@smc.vnet.net> <bopd02$oq6$1@smc.vnet.net>
- Reply-to: kuska at informatik.uni-leipzig.de
- Sender: owner-wri-mathgroup at wolfram.com
Hi,
neither nor. The question is so strange formulated, that nobody
know what you mean. You have 4 points, in the tetrahedron
formed by that points you have a interpolation function, that
depend on {x,y,z} but you do not construct that interpolation
or tell us how you wish to do that. The interpolation *is* not
a function of the 4 points, the 4 points are parameters for the
interpolation ..
Regards
Jens
mroc wrote:
>
> mroc_1000 at hotmail.com (mroc) wrote in message news:<boign7$oj1$1 at smc.vnet.net>...
> > Hello, I am totally new to Mathematica and trying to program a simple
> > FEM-type problem. I am trying to take the partial derivative
> > (symbolically) of an expression that is a function of four points in
> > 3D. All I can think of to do is F[p1,p2,p3,p4] = stuff then
> > D[F,p1,p2,p3,p4] . But I keep getting a zero expression as a result.
> > (where stuff is a nasty combination of these points) Any thoughts?
>
> Anyone? What am I missing? Is this question too easy or too hard?