OP2/PyOP2 — pull request #273 by wence- (2013-11-20 11:53:35+00:00)
Title: Unblock global to PETSc numbering in parallel case

We currently build the correct global to PETSc numbering maps for
block matrices, but can only assemble into non-block matrices. So as a
quick fix for assembling on vector function spaces in parallel, use
PETSc routines to build the appropriate unblocked maps.