How to create the MaterialIndexList for tets?

Hello Mathias,
Could you please help me on how to create MaterialIndexList for tets?
For example, how to assign a conductivity of 0.067 to tets composed of these points, and a conductivity of 1.28 to the remaining tets?
Any help would be greatly appreciated. (19.9 KB)
0513.3dm (232.3 KB)

You need to specify the tetrefs. These have to be a list of indices into the conductivities. For example, if you have two different conductivities, your tetrefs list has to have entries 0/1 according to which material each tetrahedron belongs to. The length of the list must be equal to the number of tetrahedra. The list of conductivities (called “kappa”) must have length two.
As of now, the material indices are not baked into the mesh by TRmesh (this functionality will be re-added soon, though). Instead, you have to write Grasshopper code that decides, for each tet, which material it should belong to, based on the location of its vertices.