.. _diffusion-poisson_parallel_interactive: diffusion/poisson_parallel_interactive.py ========================================= **Description** Parallel assembling and solving of a Poisson's equation, using commands for interactive use. Find :math:`u` such that: .. math:: \int_{\Omega} \nabla v \cdot \nabla u = \int_{\Omega} v f \;, \quad \forall s \;. Important Notes --------------- - This example requires petsc4py, mpi4py and (optionally) pymetis with their dependencies installed! - This example generates a number of files - do not use an existing non-empty directory for the ``output_dir`` argument. - Use the ``--clear`` option with care! Notes ----- - Each task is responsible for a subdomain consisting of a set of cells (a cell region). - Each subdomain owns PETSc DOFs within a consecutive range. - When both global and task-local variables exist, the task-local variables have ``_i`` suffix. - This example does not use a nonlinear solver. - This example can serve as a template for solving a linear single-field scalar problem - just replace the equations in :func:`create_local_problem()`. - The command line options are saved into /options.txt file. Usage Examples -------------- See all options:: python3 sfepy/examples/diffusion/poisson_parallel_interactive.py -h See PETSc options:: python3 sfepy/examples/diffusion/poisson_parallel_interactive.py -help Single process run useful for debugging with :func:`debug() `:: python3 sfepy/examples/diffusion/poisson_parallel_interactive.py output-parallel Parallel runs:: mpiexec -n 3 python3 sfepy/examples/diffusion/poisson_parallel_interactive.py output-parallel -2 --shape=101,101 mpiexec -n 3 python3 sfepy/examples/diffusion/poisson_parallel_interactive.py output-parallel -2 --shape=101,101 --metis mpiexec -n 5 python3 sfepy/examples/diffusion/poisson_parallel_interactive.py output-parallel -2 --shape=101,101 --verify --metis -ksp_monitor -ksp_converged_reason View the results using:: sfepy-view output-parallel/sol.h5 -f u:wu 1:vw .. image:: /../doc/images/gallery/diffusion-poisson_parallel_interactive.png :download:`source code ` .. literalinclude:: /../sfepy/examples/diffusion/poisson_parallel_interactive.py