Exemple #1
0
    def __init__(self):
        from pyrticle.units import SIUnitsWithNaturalConstants
        self.units = units = SIUnitsWithNaturalConstants()

        ui = PICCPyUserInterface(units)
        setup = self.setup = ui.gather()

        from pytools.log import LogManager
        import os.path
        self.logmgr = LogManager(os.path.join(setup.output_path, "pic.dat"),
                                 "w")

        from hedge.backends import guess_run_context
        self.rcon = guess_run_context([])

        if self.rcon.is_head_rank:
            mesh = self.rcon.distribute_mesh(setup.mesh)
        else:
            mesh = self.rcon.receive_mesh()

        self.discr = discr = \
                self.rcon.make_discretization(mesh,
                        order=setup.element_order,
                        debug=setup.dg_debug)

        self.logmgr.set_constant("elements_total", len(setup.mesh.elements))
        self.logmgr.set_constant("elements_local", len(mesh.elements))
        self.logmgr.set_constant("element_order", setup.element_order)

        # em operator ---------------------------------------------------------
        maxwell_kwargs = {
            "epsilon": units.EPSILON0,
            "mu": units.MU0,
            "flux_type": setup.maxwell_flux_type,
            "bdry_flux_type": setup.maxwell_bdry_flux_type
        }

        if discr.dimensions == 3:
            from hedge.models.em import MaxwellOperator
            self.maxwell_op = MaxwellOperator(**maxwell_kwargs)
        elif discr.dimensions == 2:
            from hedge.models.em import TEMaxwellOperator
            self.maxwell_op = TEMaxwellOperator(**maxwell_kwargs)
        else:
            raise ValueError, "invalid mesh dimension"

        if setup.chi is not None:
            from pyrticle.hyperbolic import ECleaningMaxwellOperator
            self.maxwell_op = ECleaningMaxwellOperator(
                self.maxwell_op, chi=setup.chi, phi_decay=setup.phi_decay)

            if setup.phi_filter is not None:
                from pyrticle.hyperbolic import PhiFilter
                from hedge.discretization import Filter, ExponentialFilterResponseFunction
                em_filters.append(
                    PhiFilter(
                        maxwell_op,
                        Filter(
                            discr,
                            ExponentialFilterResponseFunction(
                                *setup.phi_filter))))

        # timestepping setup --------------------------------------------------
        goal_dt = self.maxwell_op.estimate_timestep(discr) * setup.dt_scale
        self.nsteps = int(setup.final_time / goal_dt) + 1
        self.dt = setup.final_time / self.nsteps

        self.stepper = setup.timestepper_maker(self.dt)

        # particle setup ------------------------------------------------------
        from pyrticle.cloud import PicMethod, PicState, \
                optimize_shape_bandwidth, \
                guess_shape_bandwidth

        method = self.method = PicMethod(
            discr,
            units,
            setup.depositor,
            setup.pusher,
            dimensions_pos=setup.dimensions_pos,
            dimensions_velocity=setup.dimensions_velocity,
            debug=setup.debug)

        self.state = method.make_state()
        method.add_particles(self.state,
                             setup.distribution.generate_particles(),
                             setup.nparticles)

        self.total_charge = setup.nparticles * setup.distribution.mean()[2][0]
        if isinstance(setup.shape_bandwidth, str):
            if setup.shape_bandwidth == "optimize":
                optimize_shape_bandwidth(
                    method, self.state,
                    setup.distribution.get_rho_interpolant(
                        discr, self.total_charge), setup.shape_exponent)
            elif setup.shape_bandwidth == "guess":
                guess_shape_bandwidth(method, self.state, setup.shape_exponent)
            else:
                raise ValueError, "invalid shape bandwidth setting '%s'" % (
                    setup.shape_bandwidth)
        else:
            from pyrticle._internal import PolynomialShapeFunction
            method.depositor.set_shape_function(
                self.state,
                PolynomialShapeFunction(
                    float(setup.shape_bandwidth),
                    method.mesh_data.dimensions,
                    setup.shape_exponent,
                ))

        # initial condition ---------------------------------------------------
        if "no_ic" in setup.debug:
            self.fields = self.maxwell_op.assemble_eh(discr=discr)
        else:
            from pyrticle.cloud import compute_initial_condition
            self.fields = compute_initial_condition(
                self.rcon,
                discr,
                method,
                self.state,
                maxwell_op=self.maxwell_op,
                potential_bc=setup.potential_bc,
                force_zero=False)

        # rhs calculators -----------------------------------------------------
        from pyrticle.cloud import \
                FieldRhsCalculator, \
                FieldToParticleRhsCalculator, \
                ParticleRhsCalculator, \
                ParticleToFieldRhsCalculator
        self.f_rhs_calculator = FieldRhsCalculator(self.method,
                                                   self.maxwell_op)
        self.p_rhs_calculator = ParticleRhsCalculator(self.method,
                                                      self.maxwell_op)
        self.f2p_rhs_calculator = FieldToParticleRhsCalculator(
            self.method, self.maxwell_op)
        self.p2f_rhs_calculator = ParticleToFieldRhsCalculator(
            self.method, self.maxwell_op)

        # instrumentation setup -----------------------------------------------
        self.add_instrumentation(self.logmgr)