petsc-3.4.4 2014-03-13


  • unstructured grid An Unstructured Grid Example.
    This example demonstrates how to solve a nonlinear system in parallel
    with SNES for an unstructured mesh. The mesh and partitioning information
    is read in an application defined ordering,which is later transformed
    into another convenient ordering (called the local ordering). The local
    ordering, apart from being efficient on cpu cycles and memory, allows
    the use of the SPMD model of parallel programming. After partitioning
    is done, scatters are created between local (sequential)and global
    (distributed) vectors. Finally, we set up the nonlinear solver context
    in the usual way as a structured grid (see
    This example also illustrates the use of parallel matrix coloring.