What construct can I use to build and keep track (i.e. map over) a staggered index set, i.e. the dual (vertices, elements) meshes for a FEM application.
I am looking for the equivalent, on a regular mesh, of the `sieve` construction ( http://www.mcs.anl.gov/petsc/documentation/tutorials/sieve.pdf , which I understand to be only available for DMPLEX). I could hack together my own by using DM and IS, but I'd first like to be sure about the non-existence of current implementations. Thank you in advance, Marco
