You can infer this from the 2d numbering. For example, for the HEX8, the base is oriented wrt (xi,eta) according to the QUAD4, and zeta is the vertical direction.
On 2/16/10 3:04 PM, "Roy Stogner" <[email protected]> wrote: > > > On Tue, 16 Feb 2010, Rahul Sampath wrote: > >> HEX8: 7 6 >> o--------o >> /: /| >> / : / | >> 4 / : 5 / | >> o--------o | >> | o....|...o 2 >> | .3 | / >> | . | / >> |. |/ >> o--------o >> 0 1 >> >> TET4: >> 3 >> o >> /|\ >> / | \ >> / | \ >> 0 o...|...o 2 >> \ | / >> \ | / >> \|/ >> o >> 1 >> >> However, you have not shown the coordinate axes. I need to know the >> following: >> 1) The relationship between the local coordinate system and the local >> node numbering scheme. For example, In Hex8 whether the edge 0-1 is >> parallel to the local xi or eta axes. >> >> 2) The relationship between the physical global coordinate system and >> the local coordinate system. >> >> I believe you must already be using some convention for both to be >> able to compute the Jacobian of the transformation. It would be very >> helpful if you could tell me where I can find this information. > > To the best of my recollection: > > For triangles and tets, the nodes are at (0,0,0), (1,0,0), (0,1,0), > (0,0,1) in master coordinates > > For tensor product elements, the geometry is [-1,1]^d and the edges > are 0-1:xi, 0-3:eta, 0-4:zeta > > For pyramids, the peak is at (0,0,1) and the base is the same as a > quad. > > Prisms are the tensor product of a triangle and an edge, with the > triangle at zeta=-1 given the lower local node numbers. > > I'm afraid that the only place where you can find this information > solidly may be implicitly in the fe_lagrange*.C code, though; I'm not > sure we've got it cleanly documented. If you'd like to add such > documentation, a patch (in ASCII so we can put it in the headers) > would be appreciated. > --- > Roy > > ------------------------------------------------------------------------------ > SOLARIS 10 is the OS for Data Centers - provides features such as DTrace, > Predictive Self Healing and Award Winning ZFS. Get Solaris 10 NOW > http://p.sf.net/sfu/solaris-dev2dev > _______________________________________________ > Libmesh-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/libmesh-users ------------------------------------------------------------------------------ SOLARIS 10 is the OS for Data Centers - provides features such as DTrace, Predictive Self Healing and Award Winning ZFS. Get Solaris 10 NOW http://p.sf.net/sfu/solaris-dev2dev _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
