On Tue, 1 Jun 2010, Vijay S. Mahadevan wrote: >> Yes. We're using C-like semantics here, where if you want to access >> the 0th index in an array then the array should be at least length 1. > > Roy, I agree. But if I did want to know the dof_number associated with > the a certain variable at a node (nodal dof) that does not have any > components associated with it, then what do I specify for the third > argument. This was my dilemma and since it's an unsigned int, I wasn't > sure what else to specify. Or am I going about finding the dof_number > for the node wrongly ?
If there aren't any components associated with a variable at a node, then there doesn't exist a dof_number for that variable at that node. If you're solving Q2/Q1 velocity-pressure, for instance, you need HEX27 elements to give you enough velocity nodes, but the pressure DoFs are only located on vertex nodes; to get the pressure value on any other node you have to interpolate. Which isn't a bad idea in general. My own prejudice is that if application code uses DofObject::dof_number directly then it's probably doing something wrong, typically by making itself incompatible with non-LAGRANGE elements. --- Roy ------------------------------------------------------------------------------ _______________________________________________ Libmesh-devel mailing list Libmesh-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libmesh-devel
