Пример #1
0
def _test_node_vertex_consistency_simplex(mesh, mgrp, tol):
    if mgrp.nelements == 0:
        return True

    resampling_mat = mp.resampling_matrix(
            mp.simplex_best_available_basis(mgrp.dim, mgrp.order),
            mgrp.vertex_unit_coordinates().T,
            mgrp.unit_nodes)

    # dim, nelments, nnvertices
    map_vertices = np.einsum(
            "ij,dej->dei", resampling_mat, mgrp.nodes)

    grp_vertices = mesh.vertices[:, mgrp.vertex_indices]

    per_element_vertex_errors = np.sqrt(np.sum(
            np.sum((map_vertices - grp_vertices)**2, axis=0),
            axis=-1))

    if tol is None:
        tol = 1e3 * np.finfo(per_element_vertex_errors.dtype).eps

    from meshmode.mesh.processing import find_bounding_box

    bbox_min, bbox_max = find_bounding_box(mesh)
    size = la.norm(bbox_max-bbox_min)

    assert np.max(per_element_vertex_errors) < tol*size, \
            np.max(per_element_vertex_errors)

    return True
Пример #2
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def _test_node_vertex_consistency_simplex(mesh, mgrp):
    if mgrp.nelements == 0:
        return True

    resampling_mat = mp.resampling_matrix(
            mp.simplex_best_available_basis(mgrp.dim, mgrp.order),
            mgrp.vertex_unit_coordinates().T,
            mgrp.unit_nodes)

    # dim, nelments, nnvertices
    map_vertices = np.einsum(
            "ij,dej->dei", resampling_mat, mgrp.nodes)

    grp_vertices = mesh.vertices[:, mgrp.vertex_indices]

    per_element_vertex_errors = np.sqrt(np.sum(
            np.sum((map_vertices - grp_vertices)**2, axis=0),
            axis=-1))

    tol = 1e3 * np.finfo(per_element_vertex_errors.dtype).eps

    from meshmode.mesh.processing import find_bounding_box

    bbox_min, bbox_max = find_bounding_box(mesh)
    size = la.norm(bbox_max-bbox_min)

    assert np.max(per_element_vertex_errors) < tol*size, \
            np.max(per_element_vertex_errors)

    return True
Пример #3
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def make_element_lookup_tree(mesh, eps=1e-12):
    from meshmode.mesh.processing import find_bounding_box
    bbox_min, bbox_max = find_bounding_box(mesh)
    bbox_min -= eps
    bbox_max += eps

    tree = SpatialBinaryTreeBucket(bbox_min, bbox_max)

    for igrp, grp in enumerate(mesh.groups):
        for iel_grp in range(grp.nelements):
            el_vertices = mesh.vertices[:, grp.vertex_indices[iel_grp]]

            el_bbox_min = np.min(el_vertices, axis=-1) - eps
            el_bbox_max = np.max(el_vertices, axis=-1) + eps

            tree.insert((igrp, iel_grp), (el_bbox_min, el_bbox_max))

    return tree
Пример #4
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def make_element_lookup_tree(mesh, eps=1e-12):
    from meshmode.mesh.processing import find_bounding_box
    bbox_min, bbox_max = find_bounding_box(mesh)
    bbox_min -= eps
    bbox_max += eps

    tree = SpatialBinaryTreeBucket(bbox_min, bbox_max)

    for igrp, grp in enumerate(mesh.groups):
        for iel_grp in range(grp.nelements):
            el_vertices = mesh.vertices[:, grp.vertex_indices[iel_grp]]

            el_bbox_min = np.min(el_vertices, axis=-1) - eps
            el_bbox_max = np.max(el_vertices, axis=-1) + eps

            tree.insert((igrp, iel_grp), (el_bbox_min, el_bbox_max))

    return tree
Пример #5
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def replicate_along_axes(mesh, shape, sep_ratio):
    from meshmode.mesh.processing import (find_bounding_box, affine_map,
                                          merge_disjoint_meshes)

    bbox = find_bounding_box(mesh)
    sizes = bbox[1] - bbox[0]

    meshes = [mesh]

    for i in range(mesh.ambient_dim):
        for j in range(1, shape[i]):
            vec = np.zeros(mesh.ambient_dim)
            vec[i] = j * sizes[i] * (1 + sep_ratio)
            meshes.append(affine_map(mesh, A=None, b=vec))

        # FIXME: https://gitlab.tiker.net/inducer/pytential/issues/6
        mesh = merge_disjoint_meshes(meshes, single_group=True)
        meshes = [mesh]

    return mesh
Пример #6
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def test_lookup_tree(do_plot=False):
    from meshmode.mesh.generation import make_curve_mesh, cloverleaf
    mesh = make_curve_mesh(cloverleaf, np.linspace(0, 1, 1000), order=3)

    from meshmode.mesh.tools import make_element_lookup_tree
    tree = make_element_lookup_tree(mesh)

    from meshmode.mesh.processing import find_bounding_box
    bbox_min, bbox_max = find_bounding_box(mesh)

    extent = bbox_max - bbox_min

    for i in range(20):
        pt = bbox_min + np.random.rand(2) * extent
        print(pt)
        for igrp, iel in tree.generate_matches(pt):
            print(igrp, iel)

    if do_plot:
        with open("tree.dat", "w") as outf:
            tree.visualize(outf)
Пример #7
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def test_lookup_tree(do_plot=False):
    from meshmode.mesh.generation import make_curve_mesh, cloverleaf
    mesh = make_curve_mesh(cloverleaf, np.linspace(0, 1, 1000), order=3)

    from meshmode.mesh.tools import make_element_lookup_tree
    tree = make_element_lookup_tree(mesh)

    from meshmode.mesh.processing import find_bounding_box
    bbox_min, bbox_max = find_bounding_box(mesh)

    extent = bbox_max-bbox_min

    for i in range(20):
        pt = bbox_min + np.random.rand(2) * extent
        print(pt)
        for igrp, iel in tree.generate_matches(pt):
            print(igrp, iel)

    if do_plot:
        with open("tree.dat", "w") as outf:
            tree.visualize(outf)
Пример #8
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def _test_node_vertex_consistency_resampling(mesh, mgrp, tol):
    if mesh.vertices is None:
        return True

    if mgrp.nelements == 0:
        return True

    if isinstance(mgrp, _ModepyElementGroup):
        basis = mp.basis_for_space(mgrp._modepy_space, mgrp._modepy_shape).functions
    else:
        raise TypeError(f"unsupported group type: {type(mgrp).__name__}")

    resampling_mat = mp.resampling_matrix(
            basis,
            mgrp.vertex_unit_coordinates().T,
            mgrp.unit_nodes)

    # dim, nelments, nnvertices
    map_vertices = np.einsum(
            "ij,dej->dei", resampling_mat, mgrp.nodes)

    grp_vertices = mesh.vertices[:, mgrp.vertex_indices]

    per_element_vertex_errors = np.sqrt(np.sum(
            np.sum((map_vertices - grp_vertices)**2, axis=0),
            axis=-1))

    if tol is None:
        tol = 1e3 * np.finfo(per_element_vertex_errors.dtype).eps

    from meshmode.mesh.processing import find_bounding_box

    bbox_min, bbox_max = find_bounding_box(mesh)
    size = la.norm(bbox_max-bbox_min)

    max_el_vertex_error = np.max(per_element_vertex_errors)
    assert max_el_vertex_error < tol*size, max_el_vertex_error

    return True
Пример #9
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def test_pec_mfie_extinction(ctx_getter, case, visualize=False):
    """For (say) is_interior=False (the 'exterior' MFIE), this test verifies
    extinction of the combined (incoming + scattered) field on the interior
    of the scatterer.
    """
    logging.basicConfig(level=logging.INFO)

    cl_ctx = ctx_getter()
    queue = cl.CommandQueue(cl_ctx)

    np.random.seed(12)

    knl_kwargs = {"k": case.k}

    # {{{ come up with a solution to Maxwell's equations

    j_sym = sym.make_sym_vector("j", 3)
    jt_sym = sym.make_sym_vector("jt", 2)
    rho_sym = sym.var("rho")

    from pytential.symbolic.pde.maxwell import (
            PECChargeCurrentMFIEOperator,
            get_sym_maxwell_point_source,
            get_sym_maxwell_plane_wave)
    mfie = PECChargeCurrentMFIEOperator()

    test_source = case.get_source(queue)

    calc_patch = CalculusPatch(np.array([-3, 0, 0]), h=0.01)
    calc_patch_tgt = PointsTarget(cl.array.to_device(queue, calc_patch.points))

    rng = cl.clrandom.PhiloxGenerator(cl_ctx, seed=12)
    src_j = rng.normal(queue, (3, test_source.nnodes), dtype=np.float64)

    def eval_inc_field_at(tgt):
        if 0:
            # plane wave
            return bind(
                    tgt,
                    get_sym_maxwell_plane_wave(
                        amplitude_vec=np.array([1, 1, 1]),
                        v=np.array([1, 0, 0]),
                        omega=case.k)
                    )(queue)
        else:
            # point source
            return bind(
                    (test_source, tgt),
                    get_sym_maxwell_point_source(mfie.kernel, j_sym, mfie.k)
                    )(queue, j=src_j, k=case.k)

    pde_test_inc = EHField(
            vector_from_device(queue, eval_inc_field_at(calc_patch_tgt)))

    source_maxwell_resids = [
            calc_patch.norm(x, np.inf) / calc_patch.norm(pde_test_inc.e, np.inf)
            for x in frequency_domain_maxwell(
                calc_patch, pde_test_inc.e, pde_test_inc.h, case.k)]
    print("Source Maxwell residuals:", source_maxwell_resids)
    assert max(source_maxwell_resids) < 1e-6

    # }}}

    loc_sign = -1 if case.is_interior else +1

    from pytools.convergence import EOCRecorder

    eoc_rec_repr_maxwell = EOCRecorder()
    eoc_pec_bc = EOCRecorder()
    eoc_rec_e = EOCRecorder()
    eoc_rec_h = EOCRecorder()

    from pytential.qbx import QBXLayerPotentialSource
    from meshmode.discretization import Discretization
    from meshmode.discretization.poly_element import \
            InterpolatoryQuadratureSimplexGroupFactory
    from sumpy.expansion.level_to_order import SimpleExpansionOrderFinder

    for resolution in case.resolutions:
        scat_mesh = case.get_mesh(resolution, case.target_order)
        observation_mesh = case.get_observation_mesh(case.target_order)

        pre_scat_discr = Discretization(
                cl_ctx, scat_mesh,
                InterpolatoryQuadratureSimplexGroupFactory(case.target_order))
        qbx, _ = QBXLayerPotentialSource(
                pre_scat_discr, fine_order=4*case.target_order,
                qbx_order=case.qbx_order,
                fmm_level_to_order=SimpleExpansionOrderFinder(
                    case.fmm_tolerance),
                fmm_backend=case.fmm_backend
                ).with_refinement(_expansion_disturbance_tolerance=0.05)
        h_max = qbx.h_max

        scat_discr = qbx.density_discr
        obs_discr = Discretization(
                cl_ctx, observation_mesh,
                InterpolatoryQuadratureSimplexGroupFactory(case.target_order))

        inc_field_scat = EHField(eval_inc_field_at(scat_discr))
        inc_field_obs = EHField(eval_inc_field_at(obs_discr))

        # {{{ system solve

        inc_xyz_sym = EHField(sym.make_sym_vector("inc_fld", 6))

        bound_j_op = bind(qbx, mfie.j_operator(loc_sign, jt_sym))
        j_rhs = bind(qbx, mfie.j_rhs(inc_xyz_sym.h))(
                queue, inc_fld=inc_field_scat.field, **knl_kwargs)

        gmres_settings = dict(
                tol=case.gmres_tol,
                progress=True,
                hard_failure=True,
                stall_iterations=50, no_progress_factor=1.05)
        from pytential.solve import gmres
        gmres_result = gmres(
                bound_j_op.scipy_op(queue, "jt", np.complex128, **knl_kwargs),
                j_rhs, **gmres_settings)

        jt = gmres_result.solution

        bound_rho_op = bind(qbx, mfie.rho_operator(loc_sign, rho_sym))
        rho_rhs = bind(qbx, mfie.rho_rhs(jt_sym, inc_xyz_sym.e))(
                queue, jt=jt, inc_fld=inc_field_scat.field, **knl_kwargs)

        gmres_result = gmres(
                bound_rho_op.scipy_op(queue, "rho", np.complex128, **knl_kwargs),
                rho_rhs, **gmres_settings)

        rho = gmres_result.solution

        # }}}

        jxyz = bind(qbx, sym.tangential_to_xyz(jt_sym))(queue, jt=jt)

        # {{{ volume eval

        sym_repr = mfie.scattered_volume_field(jt_sym, rho_sym)

        def eval_repr_at(tgt, source=None):
            if source is None:
                source = qbx

            return bind((source, tgt), sym_repr)(queue, jt=jt, rho=rho, **knl_kwargs)

        pde_test_repr = EHField(
                vector_from_device(queue, eval_repr_at(calc_patch_tgt)))

        maxwell_residuals = [
                calc_patch.norm(x, np.inf) / calc_patch.norm(pde_test_repr.e, np.inf)
                for x in frequency_domain_maxwell(
                    calc_patch, pde_test_repr.e, pde_test_repr.h, case.k)]
        print("Maxwell residuals:", maxwell_residuals)

        eoc_rec_repr_maxwell.add_data_point(h_max, max(maxwell_residuals))

        # }}}

        # {{{ check PEC BC on total field

        bc_repr = EHField(mfie.scattered_volume_field(
            jt_sym, rho_sym, qbx_forced_limit=loc_sign))
        pec_bc_e = sym.n_cross(bc_repr.e + inc_xyz_sym.e)
        pec_bc_h = sym.normal(3).as_vector().dot(bc_repr.h + inc_xyz_sym.h)

        eh_bc_values = bind(qbx, sym.join_fields(pec_bc_e, pec_bc_h))(
                    queue, jt=jt, rho=rho, inc_fld=inc_field_scat.field,
                    **knl_kwargs)

        def scat_norm(f):
            return norm(qbx, queue, f, p=np.inf)

        e_bc_residual = scat_norm(eh_bc_values[:3]) / scat_norm(inc_field_scat.e)
        h_bc_residual = scat_norm(eh_bc_values[3]) / scat_norm(inc_field_scat.h)

        print("E/H PEC BC residuals:", h_max, e_bc_residual, h_bc_residual)

        eoc_pec_bc.add_data_point(h_max, max(e_bc_residual, h_bc_residual))

        # }}}

        # {{{ visualization

        if visualize:
            from meshmode.discretization.visualization import make_visualizer
            bdry_vis = make_visualizer(queue, scat_discr, case.target_order+3)

            bdry_normals = bind(scat_discr, sym.normal(3))(queue)\
                    .as_vector(dtype=object)

            bdry_vis.write_vtk_file("source-%s.vtu" % resolution, [
                ("j", jxyz),
                ("rho", rho),
                ("Einc", inc_field_scat.e),
                ("Hinc", inc_field_scat.h),
                ("bdry_normals", bdry_normals),
                ("e_bc_residual", eh_bc_values[:3]),
                ("h_bc_residual", eh_bc_values[3]),
                ])

            fplot = make_field_plotter_from_bbox(
                    find_bounding_box(scat_discr.mesh), h=(0.05, 0.05, 0.3),
                    extend_factor=0.3)

            from pytential.qbx import QBXTargetAssociationFailedException

            qbx_tgt_tol = qbx.copy(target_association_tolerance=0.2)

            fplot_tgt = PointsTarget(cl.array.to_device(queue, fplot.points))
            try:
                fplot_repr = eval_repr_at(fplot_tgt, source=qbx_tgt_tol)
            except QBXTargetAssociationFailedException as e:
                fplot.write_vtk_file(
                        "failed-targets.vts",
                        [
                            ("failed_targets", e.failed_target_flags.get(queue))
                            ])
                raise

            fplot_repr = EHField(vector_from_device(queue, fplot_repr))

            fplot_inc = EHField(
                    vector_from_device(queue, eval_inc_field_at(fplot_tgt)))

            fplot.write_vtk_file(
                    "potential-%s.vts" % resolution,
                    [
                        ("E", fplot_repr.e),
                        ("H", fplot_repr.h),
                        ("Einc", fplot_inc.e),
                        ("Hinc", fplot_inc.h),
                        ]
                    )

        # }}}

        # {{{ error in E, H

        obs_repr = EHField(eval_repr_at(obs_discr))

        def obs_norm(f):
            return norm(obs_discr, queue, f, p=np.inf)

        rel_err_e = (obs_norm(inc_field_obs.e + obs_repr.e)
                / obs_norm(inc_field_obs.e))
        rel_err_h = (obs_norm(inc_field_obs.h + obs_repr.h)
                / obs_norm(inc_field_obs.h))

        # }}}

        print("ERR", h_max, rel_err_h, rel_err_e)

        eoc_rec_h.add_data_point(h_max, rel_err_h)
        eoc_rec_e.add_data_point(h_max, rel_err_e)

    print("--------------------------------------------------------")
    print("is_interior=%s" % case.is_interior)
    print("--------------------------------------------------------")

    good = True
    for which_eoc, eoc_rec, order_tol in [
            ("maxwell", eoc_rec_repr_maxwell, 1.5),
            ("PEC BC", eoc_pec_bc, 1.5),
            ("H", eoc_rec_h, 1.5),
            ("E", eoc_rec_e, 1.5)]:
        print(which_eoc)
        print(eoc_rec.pretty_print())

        if len(eoc_rec.history) > 1:
            if eoc_rec.order_estimate() < case.qbx_order - order_tol:
                good = False

    assert good
Пример #10
0
def main():
    # cl.array.to_device(queue, numpy_array)
    from meshmode.mesh.io import generate_gmsh, FileSource
    mesh = generate_gmsh(
            FileSource("ellipsoid.step"), 2, order=2,
            other_options=["-string", "Mesh.CharacteristicLengthMax = %g;" % h])

    from meshmode.mesh.processing import perform_flips
    # Flip elements--gmsh generates inside-out geometry.
    mesh = perform_flips(mesh, np.ones(mesh.nelements))

    print("%d elements" % mesh.nelements)

    from meshmode.mesh.processing import find_bounding_box
    bbox_min, bbox_max = find_bounding_box(mesh)
    bbox_center = 0.5*(bbox_min+bbox_max)
    bbox_size = max(bbox_max-bbox_min) / 2

    logger.info("%d elements" % mesh.nelements)

    from pytential.qbx import QBXLayerPotentialSource
    from meshmode.discretization import Discretization
    from meshmode.discretization.poly_element import \
            InterpolatoryQuadratureSimplexGroupFactory

    density_discr = Discretization(
            cl_ctx, mesh, InterpolatoryQuadratureSimplexGroupFactory(target_order))

    qbx = QBXLayerPotentialSource(density_discr, 4*target_order, qbx_order,
            fmm_order=qbx_order + 10, fmm_backend="fmmlib")

    from pytential.symbolic.pde.maxwell import MuellerAugmentedMFIEOperator
    pde_op = MuellerAugmentedMFIEOperator(
            omega=0.4,
            epss=[1.4, 1.0],
            mus=[1.2, 1.0],
            )
    from pytential import bind, sym

    unk = pde_op.make_unknown("sigma")
    sym_operator = pde_op.operator(unk)
    sym_rhs = pde_op.rhs(
            sym.make_sym_vector("Einc", 3),
            sym.make_sym_vector("Hinc", 3))
    sym_repr = pde_op.representation(0, unk)

    if 1:
        expr = sym_repr
        print(sym.pretty(expr))

        print("#"*80)
        from pytential.target import PointsTarget

        tgt_points=np.zeros((3,1))
        tgt_points[0,0] = 100
        tgt_points[1,0] = -200
        tgt_points[2,0] = 300

        bound_op = bind((qbx, PointsTarget(tgt_points)), expr)
        print(bound_op.code)

    if 1:

        def green3e(x,y,z,source,strength,k):
        # electric field corresponding to dyadic green's function
        # due to monochromatic electric dipole located at "source".
        # "strength" is the the intensity of the dipole.
        #  E = (I + Hess)(exp(ikr)/r) dot (strength)
        #
            dx = x - source[0]
            dy = y - source[1]
            dz = z - source[2]
            rr = np.sqrt(dx**2 + dy**2 + dz**2)

            fout = np.exp(1j*k*rr)/rr
            evec = fout*strength
            qmat = np.zeros((3,3),dtype=np.complex128)

            qmat[0,0]=(2*dx**2-dy**2-dz**2)*(1-1j*k*rr)
            qmat[1,1]=(2*dy**2-dz**2-dx**2)*(1-1j*k*rr)
            qmat[2,2]=(2*dz**2-dx**2-dy**2)*(1-1j*k*rr)

            qmat[0,0]=qmat[0,0]+(-k**2*dx**2*rr**2)
            qmat[1,1]=qmat[1,1]+(-k**2*dy**2*rr**2)
            qmat[2,2]=qmat[2,2]+(-k**2*dz**2*rr**2)

            qmat[0,1]=(3-k**2*rr**2-3*1j*k*rr)*(dx*dy)
            qmat[1,2]=(3-k**2*rr**2-3*1j*k*rr)*(dy*dz)
            qmat[2,0]=(3-k**2*rr**2-3*1j*k*rr)*(dz*dx)

            qmat[1,0]=qmat[0,1]
            qmat[2,1]=qmat[1,2]
            qmat[0,2]=qmat[2,0]

            fout=np.exp(1j*k*rr)/rr**5/k**2

            fvec = fout*np.dot(qmat,strength)
            evec = evec + fvec
            return evec

        def green3m(x,y,z,source,strength,k):
        # magnetic field corresponding to dyadic green's function
        # due to monochromatic electric dipole located at "source".
        # "strength" is the the intensity of the dipole.
        #  H = curl((I + Hess)(exp(ikr)/r) dot (strength)) = 
        #  strength \cross \grad (exp(ikr)/r)
        #
            dx = x - source[0]
            dy = y - source[1]
            dz = z - source[2]
            rr = np.sqrt(dx**2 + dy**2 + dz**2)

            fout=(1-1j*k*rr)*np.exp(1j*k*rr)/rr**3
            fvec = np.zeros(3,dtype=np.complex128)
            fvec[0] = fout*dx
            fvec[1] = fout*dy
            fvec[2] = fout*dz

            hvec = np.cross(strength,fvec)

            return hvec

        def dipole3e(x,y,z,source,strength,k):
        #
        #  evalaute electric and magnetic field due
        #  to monochromatic electric dipole located at "source"
        #  with intensity "strength"

            evec = green3e(x,y,z,source,strength,k)
            evec = evec*1j*k
            hvec = green3m(x,y,z,source,strength,k)
            return evec,hvec
            
        def dipole3m(x,y,z,source,strength,k):
        #
        #  evalaute electric and magnetic field due
        #  to monochromatic magnetic dipole located at "source"
        #  with intensity "strength"
            evec = green3m(x,y,z,source,strength,k)
            hvec = green3e(x,y,z,source,strength,k)
            hvec = -hvec*1j*k
            return evec,hvec
            

        def dipole3eall(x,y,z,sources,strengths,k):
            ns = len(strengths)
            evec = np.zeros(3,dtype=np.complex128)
            hvec = np.zeros(3,dtype=np.complex128)

            for i in range(ns):
                evect,hvect = dipole3e(x,y,z,sources[i],strengths[i],k)
                evec = evec + evect
                hvec = hvec + hvect

        nodes = density_discr.nodes().with_queue(queue).get()
        source = [0.01,-0.03,0.02]
#        source = cl.array.to_device(queue,np.zeros(3))
#        source[0] = 0.01
#        source[1] =-0.03
#        source[2] = 0.02
        strength = np.ones(3)
       
#        evec = cl.array.to_device(queue,np.zeros((3,len(nodes[0])),dtype=np.complex128))
#        hvec = cl.array.to_device(queue,np.zeros((3,len(nodes[0])),dtype=np.complex128))

        evec = np.zeros((3,len(nodes[0])),dtype=np.complex128)
        hvec = np.zeros((3,len(nodes[0])),dtype=np.complex128)
        for i in range(len(nodes[0])):
            evec[:,i],hvec[:,i] = dipole3e(nodes[0][i],nodes[1][i],nodes[2][i],source,strength,k)
        print(np.shape(hvec))
        print(type(evec))
        print(type(hvec))

        evec = cl.array.to_device(queue,evec)
        hvec = cl.array.to_device(queue,hvec)

        bvp_rhs = bind(qbx, sym_rhs)(queue,Einc=evec,Hinc=hvec)
        print(np.shape(bvp_rhs))
        print(type(bvp_rhs))
#        print(bvp_rhs)
        1/-1

        bound_op = bind(qbx, sym_operator)

        from pytential.solve import gmres
        if 0:
            gmres_result = gmres(
                bound_op.scipy_op(queue, "sigma", dtype=np.complex128, k=k),
                bvp_rhs, tol=1e-8, progress=True,
                stall_iterations=0,
                hard_failure=True)

            sigma = gmres_result.solution

        fld_at_tgt = bind((qbx, PointsTarget(tgt_points)), sym_repr)(queue,
        sigma=bvp_rhs,k=k)
        fld_at_tgt = np.array([
            fi.get() for fi in fld_at_tgt
            ])
        print(fld_at_tgt)
        1/0

    # }}}

    #mlab.figure(bgcolor=(1, 1, 1))
    if 1:
        from meshmode.discretization.visualization import make_visualizer
        bdry_vis = make_visualizer(queue, density_discr, target_order)

        bdry_normals = bind(density_discr, sym.normal(3))(queue)\
                .as_vector(dtype=object)

        bdry_vis.write_vtk_file("source.vtu", [
            ("sigma", sigma),
            ("bdry_normals", bdry_normals),
            ])

        fplot = FieldPlotter(bbox_center, extent=2*bbox_size, npoints=(150, 150, 1))

        qbx_tgt_tol = qbx.copy(target_association_tolerance=0.1)
        from pytential.target import PointsTarget
        from pytential.qbx import QBXTargetAssociationFailedException

        rho_sym = sym.var("rho")

        try:
            fld_in_vol = bind(
                    (qbx_tgt_tol, PointsTarget(fplot.points)),
                    sym.make_obj_array([
                        sym.S(pde_op.kernel, rho_sym, k=sym.var("k"),
                            qbx_forced_limit=None),
                        sym.d_dx(3, sym.S(pde_op.kernel, rho_sym, k=sym.var("k"),
                            qbx_forced_limit=None)),
                        sym.d_dy(3, sym.S(pde_op.kernel, rho_sym, k=sym.var("k"),
                            qbx_forced_limit=None)),
                        sym.d_dz(3, sym.S(pde_op.kernel, rho_sym, k=sym.var("k"),
                            qbx_forced_limit=None)),
                        ])
                    )(queue, jt=jt, rho=rho, k=k)
        except QBXTargetAssociationFailedException as e:
            fplot.write_vtk_file(
                    "failed-targets.vts",
                    [
                        ("failed_targets", e.failed_target_flags.get(queue))
                        ])
            raise

        fld_in_vol = sym.make_obj_array(
            [fiv.get() for fiv in fld_in_vol])

        #fplot.show_scalar_in_mayavi(fld_in_vol.real, max_val=5)
        fplot.write_vtk_file(
                "potential.vts",
                [
                    ("potential", fld_in_vol[0]),
                    ("grad", fld_in_vol[1:]),
                    ]
                )
def draw_2d_mesh(mesh,
                 draw_vertex_numbers=True,
                 draw_element_numbers=True,
                 draw_nodal_adjacency=False,
                 draw_face_numbers=False,
                 set_bounding_box=False,
                 **kwargs):
    assert mesh.ambient_dim == 2

    import matplotlib.pyplot as pt
    import matplotlib.patches as mpatches
    from matplotlib.path import Path

    for igrp, grp in enumerate(mesh.groups):
        for iel, el in enumerate(grp.vertex_indices):
            elverts = mesh.vertices[:, el]

            from meshmode.mesh import TensorProductElementGroup
            if isinstance(grp, TensorProductElementGroup) and grp.dim == 2:
                elverts = elverts[:, np.array([0, 1, 3, 2])]

            pathdata = [
                (Path.MOVETO, (elverts[0, 0], elverts[1, 0])),
            ]
            for i in range(1, elverts.shape[1]):
                pathdata.append((Path.LINETO, (elverts[0, i], elverts[1, i])))
            pathdata.append((Path.CLOSEPOLY, (elverts[0, 0], elverts[1, 0])))

            codes, verts = zip(*pathdata)
            path = Path(verts, codes)
            patch = mpatches.PathPatch(path, **kwargs)
            pt.gca().add_patch(patch)

            if draw_element_numbers:
                centroid = (np.sum(elverts, axis=1) / elverts.shape[1])

                if len(mesh.groups) == 1:
                    el_label = str(iel)
                else:
                    el_label = "%d:%d" % (igrp, iel)

                pt.text(centroid[0],
                        centroid[1],
                        el_label,
                        fontsize=17,
                        ha="center",
                        va="center",
                        bbox=dict(facecolor="white", alpha=0.5, lw=0))

    if draw_vertex_numbers:
        for ivert, vert in enumerate(mesh.vertices.T):
            pt.text(vert[0],
                    vert[1],
                    str(ivert),
                    fontsize=15,
                    ha="center",
                    va="center",
                    color="blue",
                    bbox=dict(facecolor="white", alpha=0.5, lw=0))

    if draw_nodal_adjacency:

        def global_iel_to_group_and_iel(global_iel):
            for igrp, grp in enumerate(mesh.groups):
                if global_iel < grp.nelements:
                    return grp, global_iel
                global_iel -= grp.nelements

            raise ValueError("invalid element nr")

        cnx = mesh.nodal_adjacency

        nb_starts = cnx.neighbors_starts
        for iel_g in range(mesh.nelements):
            for nb_iel_g in cnx.neighbors[nb_starts[iel_g]:nb_starts[iel_g +
                                                                     1]]:
                assert iel_g != nb_iel_g

                grp, iel = global_iel_to_group_and_iel(iel_g)
                nb_grp, nb_iel = global_iel_to_group_and_iel(nb_iel_g)

                elverts = mesh.vertices[:, grp.vertex_indices[iel]]
                nb_elverts = mesh.vertices[:, nb_grp.vertex_indices[nb_iel]]

                centroid = (np.sum(elverts, axis=1) / elverts.shape[1])
                nb_centroid = (np.sum(nb_elverts, axis=1) /
                               nb_elverts.shape[1])

                dx = nb_centroid - centroid
                start = centroid + 0.15 * dx

                mag = np.max(np.abs(dx))
                start += 0.05 * (np.random.rand(2) - 0.5) * mag
                dx += 0.05 * (np.random.rand(2) - 0.5) * mag

                pt.arrow(start[0],
                         start[1],
                         0.7 * dx[0],
                         0.7 * dx[1],
                         length_includes_head=True,
                         color="green",
                         head_width=1e-2,
                         lw=1e-2)

    if draw_face_numbers:
        for igrp, grp in enumerate(mesh.groups):
            for iel, el in enumerate(grp.vertex_indices):
                elverts = mesh.vertices[:, el]
                el_center = np.mean(elverts, axis=-1)

                for iface, fvi in enumerate(grp.face_vertex_indices()):
                    face_center = (0.3 * el_center +
                                   0.7 * np.mean(elverts[:, fvi], axis=-1))

                    pt.text(face_center[0],
                            face_center[1],
                            str(iface),
                            fontsize=12,
                            ha="center",
                            va="center",
                            color="purple",
                            bbox=dict(facecolor="white", alpha=0.5, lw=0))

    if set_bounding_box:
        from meshmode.mesh.processing import find_bounding_box
        lower, upper = find_bounding_box(mesh)
        pt.xlim([lower[0], upper[0]])
        pt.ylim([lower[1], upper[1]])
Пример #12
0
            "point_source": point_source,
            "point_target": point_target
            }

    # plotting grid points
    ambient_dim = qbx.ambient_dim
    if visualize:
        vis_grid_spacing = getattr(case, "vis_grid_spacing",
                (0.1, 0.1, 0.1)[:ambient_dim]
                )
        vis_extend_factor = getattr(case, "vis_extend_factor", 0.2)

        from sumpy.visualization import make_field_plotter_from_bbox
        from meshmode.mesh.processing import find_bounding_box
        fplot = make_field_plotter_from_bbox(
                find_bounding_box(qbx.density_discr.mesh),
                h=vis_grid_spacing,
                extend_factor=vis_extend_factor)

        from pytential.target import PointsTarget
        plot_targets = PointsTarget(fplot.points)

        places.update({
            "qbx_target_tol": qbx.copy(target_association_tolerance=0.15),
            "plot_targets": plot_targets
            })

    places = GeometryCollection(places, auto_where=case.name)
    if case.use_refinement:
        from pytential.qbx.refinement import refine_geometry_collection
        places = refine_geometry_collection(places, **refiner_extra_kwargs)
Пример #13
0
def main():
    import logging
    logger = logging.getLogger(__name__)
    logging.basicConfig(level=logging.WARNING)  # INFO for more progress info

    from meshmode.mesh.io import generate_gmsh, FileSource
    mesh = generate_gmsh(
            FileSource(cad_file_name), 2, order=2,
            other_options=["-string", "Mesh.CharacteristicLengthMax = %g;" % h])

    from meshmode.mesh.processing import perform_flips
    # Flip elements--gmsh generates inside-out geometry.
    mesh = perform_flips(mesh, np.ones(mesh.nelements))

    from meshmode.mesh.processing import find_bounding_box
    bbox_min, bbox_max = find_bounding_box(mesh)
    bbox_center = 0.5*(bbox_min+bbox_max)
    bbox_size = max(bbox_max-bbox_min) / 2

    logger.info("%d elements" % mesh.nelements)

    from pytential.qbx import QBXLayerPotentialSource
    from meshmode.discretization import Discretization
    from meshmode.discretization.poly_element import \
            InterpolatoryQuadratureSimplexGroupFactory

    density_discr = Discretization(
            cl_ctx, mesh, InterpolatoryQuadratureSimplexGroupFactory(target_order))

    qbx, _ = QBXLayerPotentialSource(density_discr, 4*target_order, qbx_order,
            fmm_order=qbx_order + 3,
            target_association_tolerance=0.15).with_refinement()

    nodes = density_discr.nodes().with_queue(queue)

    angle = cl.clmath.atan2(nodes[1], nodes[0])

    from pytential import bind, sym
    #op = sym.d_dx(sym.S(kernel, sym.var("sigma"), qbx_forced_limit=None))
    op = sym.D(kernel, sym.var("sigma"), qbx_forced_limit=None)
    #op = sym.S(kernel, sym.var("sigma"), qbx_forced_limit=None)

    sigma = cl.clmath.cos(mode_nr*angle)
    if 0:
        sigma = 0*angle
        from random import randrange
        for i in range(5):
            sigma[randrange(len(sigma))] = 1

    if isinstance(kernel, HelmholtzKernel):
        sigma = sigma.astype(np.complex128)

    fplot = FieldPlotter(bbox_center, extent=3.5*bbox_size, npoints=150)

    from pytential.target import PointsTarget
    fld_in_vol = bind(
            (qbx, PointsTarget(fplot.points)),
            op)(queue, sigma=sigma, k=k).get()

    #fplot.show_scalar_in_mayavi(fld_in_vol.real, max_val=5)
    fplot.write_vtk_file(
            "potential-3d.vts",
            [
                ("potential", fld_in_vol)
                ]
            )

    bdry_normals = bind(
            density_discr,
            sym.normal(density_discr.ambient_dim))(queue).as_vector(dtype=object)

    from meshmode.discretization.visualization import make_visualizer
    bdry_vis = make_visualizer(queue, density_discr, target_order)

    bdry_vis.write_vtk_file("source-3d.vtu", [
        ("sigma", sigma),
        ("bdry_normals", bdry_normals),
        ])
Пример #14
0
                ("u", u),
                ("bc", bc),
                #("bdry_normals", bdry_normals),
            ])

        from sumpy.visualization import make_field_plotter_from_bbox  # noqa
        from meshmode.mesh.processing import find_bounding_box

        vis_grid_spacing = (0.1, 0.1, 0.1)[:qbx.ambient_dim]
        if hasattr(case, "vis_grid_spacing"):
            vis_grid_spacing = case.vis_grid_spacing
        vis_extend_factor = 0.2
        if hasattr(case, "vis_extend_factor"):
            vis_grid_spacing = case.vis_grid_spacing

        fplot = make_field_plotter_from_bbox(find_bounding_box(mesh),
                                             h=vis_grid_spacing,
                                             extend_factor=vis_extend_factor)

        qbx_tgt_tol = qbx.copy(target_association_tolerance=0.15)
        from pytential.target import PointsTarget

        try:
            solved_pot = bind((qbx_tgt_tol, PointsTarget(fplot.points)),
                              op.representation(sym.var("u")))(queue,
                                                               u=weighted_u,
                                                               k=case.k)
        except QBXTargetAssociationFailedException as e:
            fplot.write_vtk_file(
                "failed-targets.vts",
                [("failed_targets", e.failed_target_flags.get(queue))])
Пример #15
0
    places = {
        case.name: qbx,
        "point_source": point_source,
        "point_target": point_target
    }

    # plotting grid points
    ambient_dim = qbx.ambient_dim
    if visualize:
        vis_grid_spacing = getattr(case, "vis_grid_spacing",
                                   (0.1, 0.1, 0.1)[:ambient_dim])
        vis_extend_factor = getattr(case, "vis_extend_factor", 0.2)

        from sumpy.visualization import make_field_plotter_from_bbox
        from meshmode.mesh.processing import find_bounding_box
        fplot = make_field_plotter_from_bbox(find_bounding_box(
            qbx.density_discr.mesh),
                                             h=vis_grid_spacing,
                                             extend_factor=vis_extend_factor)

        from pytential.target import PointsTarget
        plot_targets = PointsTarget(fplot.points)

        places.update({
            "qbx_target_tol":
            qbx.copy(target_association_tolerance=0.15),
            "plot_targets":
            plot_targets
        })

    places = GeometryCollection(places, auto_where=case.name)
    if case.use_refinement:
Пример #16
0
def main():
    # cl.array.to_device(queue, numpy_array)
    from meshmode.mesh.io import generate_gmsh, FileSource
    mesh = generate_gmsh(
        FileSource("ellipsoid.step"),
        2,
        order=2,
        other_options=["-string",
                       "Mesh.CharacteristicLengthMax = %g;" % h])

    from meshmode.mesh.processing import perform_flips
    # Flip elements--gmsh generates inside-out geometry.
    mesh = perform_flips(mesh, np.ones(mesh.nelements))

    print("%d elements" % mesh.nelements)

    from meshmode.mesh.processing import find_bounding_box
    bbox_min, bbox_max = find_bounding_box(mesh)
    bbox_center = 0.5 * (bbox_min + bbox_max)
    bbox_size = max(bbox_max - bbox_min) / 2

    logger.info("%d elements" % mesh.nelements)

    from pytential.qbx import QBXLayerPotentialSource
    from meshmode.discretization import Discretization
    from meshmode.discretization.poly_element import \
            InterpolatoryQuadratureSimplexGroupFactory

    density_discr = Discretization(
        cl_ctx, mesh, InterpolatoryQuadratureSimplexGroupFactory(target_order))

    qbx = QBXLayerPotentialSource(density_discr,
                                  4 * target_order,
                                  qbx_order,
                                  fmm_order=qbx_order + 10,
                                  fmm_backend="fmmlib")

    from pytential.symbolic.pde.maxwell import MuellerAugmentedMFIEOperator
    pde_op = MuellerAugmentedMFIEOperator(
        omega=0.4,
        epss=[1.4, 1.0],
        mus=[1.2, 1.0],
    )
    from pytential import bind, sym

    unk = pde_op.make_unknown("sigma")
    sym_operator = pde_op.operator(unk)
    sym_rhs = pde_op.rhs(sym.make_sym_vector("Einc", 3),
                         sym.make_sym_vector("Hinc", 3))
    sym_repr = pde_op.representation(0, unk)

    if 1:
        expr = sym_repr
        print(sym.pretty(expr))

        print("#" * 80)
        from pytential.target import PointsTarget

        tgt_points = np.zeros((3, 1))
        tgt_points[0, 0] = 100
        tgt_points[1, 0] = -200
        tgt_points[2, 0] = 300

        bound_op = bind((qbx, PointsTarget(tgt_points)), expr)
        print(bound_op.code)

    if 1:

        def green3e(x, y, z, source, strength, k):
            # electric field corresponding to dyadic green's function
            # due to monochromatic electric dipole located at "source".
            # "strength" is the the intensity of the dipole.
            #  E = (I + Hess)(exp(ikr)/r) dot (strength)
            #
            dx = x - source[0]
            dy = y - source[1]
            dz = z - source[2]
            rr = np.sqrt(dx**2 + dy**2 + dz**2)

            fout = np.exp(1j * k * rr) / rr
            evec = fout * strength
            qmat = np.zeros((3, 3), dtype=np.complex128)

            qmat[0, 0] = (2 * dx**2 - dy**2 - dz**2) * (1 - 1j * k * rr)
            qmat[1, 1] = (2 * dy**2 - dz**2 - dx**2) * (1 - 1j * k * rr)
            qmat[2, 2] = (2 * dz**2 - dx**2 - dy**2) * (1 - 1j * k * rr)

            qmat[0, 0] = qmat[0, 0] + (-k**2 * dx**2 * rr**2)
            qmat[1, 1] = qmat[1, 1] + (-k**2 * dy**2 * rr**2)
            qmat[2, 2] = qmat[2, 2] + (-k**2 * dz**2 * rr**2)

            qmat[0, 1] = (3 - k**2 * rr**2 - 3 * 1j * k * rr) * (dx * dy)
            qmat[1, 2] = (3 - k**2 * rr**2 - 3 * 1j * k * rr) * (dy * dz)
            qmat[2, 0] = (3 - k**2 * rr**2 - 3 * 1j * k * rr) * (dz * dx)

            qmat[1, 0] = qmat[0, 1]
            qmat[2, 1] = qmat[1, 2]
            qmat[0, 2] = qmat[2, 0]

            fout = np.exp(1j * k * rr) / rr**5 / k**2

            fvec = fout * np.dot(qmat, strength)
            evec = evec + fvec
            return evec

        def green3m(x, y, z, source, strength, k):
            # magnetic field corresponding to dyadic green's function
            # due to monochromatic electric dipole located at "source".
            # "strength" is the the intensity of the dipole.
            #  H = curl((I + Hess)(exp(ikr)/r) dot (strength)) =
            #  strength \cross \grad (exp(ikr)/r)
            #
            dx = x - source[0]
            dy = y - source[1]
            dz = z - source[2]
            rr = np.sqrt(dx**2 + dy**2 + dz**2)

            fout = (1 - 1j * k * rr) * np.exp(1j * k * rr) / rr**3
            fvec = np.zeros(3, dtype=np.complex128)
            fvec[0] = fout * dx
            fvec[1] = fout * dy
            fvec[2] = fout * dz

            hvec = np.cross(strength, fvec)

            return hvec

        def dipole3e(x, y, z, source, strength, k):
            #
            #  evalaute electric and magnetic field due
            #  to monochromatic electric dipole located at "source"
            #  with intensity "strength"

            evec = green3e(x, y, z, source, strength, k)
            evec = evec * 1j * k
            hvec = green3m(x, y, z, source, strength, k)
            return evec, hvec

        def dipole3m(x, y, z, source, strength, k):
            #
            #  evalaute electric and magnetic field due
            #  to monochromatic magnetic dipole located at "source"
            #  with intensity "strength"
            evec = green3m(x, y, z, source, strength, k)
            hvec = green3e(x, y, z, source, strength, k)
            hvec = -hvec * 1j * k
            return evec, hvec

        def dipole3eall(x, y, z, sources, strengths, k):
            ns = len(strengths)
            evec = np.zeros(3, dtype=np.complex128)
            hvec = np.zeros(3, dtype=np.complex128)

            for i in range(ns):
                evect, hvect = dipole3e(x, y, z, sources[i], strengths[i], k)
                evec = evec + evect
                hvec = hvec + hvect

        nodes = density_discr.nodes().with_queue(queue).get()
        source = [0.01, -0.03, 0.02]
        #        source = cl.array.to_device(queue,np.zeros(3))
        #        source[0] = 0.01
        #        source[1] =-0.03
        #        source[2] = 0.02
        strength = np.ones(3)

        #        evec = cl.array.to_device(queue,np.zeros((3,len(nodes[0])),dtype=np.complex128))
        #        hvec = cl.array.to_device(queue,np.zeros((3,len(nodes[0])),dtype=np.complex128))

        evec = np.zeros((3, len(nodes[0])), dtype=np.complex128)
        hvec = np.zeros((3, len(nodes[0])), dtype=np.complex128)
        for i in range(len(nodes[0])):
            evec[:, i], hvec[:, i] = dipole3e(nodes[0][i], nodes[1][i],
                                              nodes[2][i], source, strength, k)
        print(np.shape(hvec))
        print(type(evec))
        print(type(hvec))

        evec = cl.array.to_device(queue, evec)
        hvec = cl.array.to_device(queue, hvec)

        bvp_rhs = bind(qbx, sym_rhs)(queue, Einc=evec, Hinc=hvec)
        print(np.shape(bvp_rhs))
        print(type(bvp_rhs))
        #        print(bvp_rhs)
        1 / -1

        bound_op = bind(qbx, sym_operator)

        from pytential.solve import gmres
        if 0:
            gmres_result = gmres(bound_op.scipy_op(queue,
                                                   "sigma",
                                                   dtype=np.complex128,
                                                   k=k),
                                 bvp_rhs,
                                 tol=1e-8,
                                 progress=True,
                                 stall_iterations=0,
                                 hard_failure=True)

            sigma = gmres_result.solution

        fld_at_tgt = bind((qbx, PointsTarget(tgt_points)),
                          sym_repr)(queue, sigma=bvp_rhs, k=k)
        fld_at_tgt = np.array([fi.get() for fi in fld_at_tgt])
        print(fld_at_tgt)
        1 / 0

    # }}}

    #mlab.figure(bgcolor=(1, 1, 1))
    if 1:
        from meshmode.discretization.visualization import make_visualizer
        bdry_vis = make_visualizer(queue, density_discr, target_order)

        bdry_normals = bind(density_discr, sym.normal(3))(queue)\
                .as_vector(dtype=object)

        bdry_vis.write_vtk_file("source.vtu", [
            ("sigma", sigma),
            ("bdry_normals", bdry_normals),
        ])

        fplot = FieldPlotter(bbox_center,
                             extent=2 * bbox_size,
                             npoints=(150, 150, 1))

        qbx_tgt_tol = qbx.copy(target_association_tolerance=0.1)
        from pytential.target import PointsTarget
        from pytential.qbx import QBXTargetAssociationFailedException

        rho_sym = sym.var("rho")

        try:
            fld_in_vol = bind((qbx_tgt_tol, PointsTarget(fplot.points)),
                              sym.make_obj_array([
                                  sym.S(pde_op.kernel,
                                        rho_sym,
                                        k=sym.var("k"),
                                        qbx_forced_limit=None),
                                  sym.d_dx(
                                      3,
                                      sym.S(pde_op.kernel,
                                            rho_sym,
                                            k=sym.var("k"),
                                            qbx_forced_limit=None)),
                                  sym.d_dy(
                                      3,
                                      sym.S(pde_op.kernel,
                                            rho_sym,
                                            k=sym.var("k"),
                                            qbx_forced_limit=None)),
                                  sym.d_dz(
                                      3,
                                      sym.S(pde_op.kernel,
                                            rho_sym,
                                            k=sym.var("k"),
                                            qbx_forced_limit=None)),
                              ]))(queue, jt=jt, rho=rho, k=k)
        except QBXTargetAssociationFailedException as e:
            fplot.write_vtk_file(
                "failed-targets.vts",
                [("failed_targets", e.failed_target_flags.get(queue))])
            raise

        fld_in_vol = sym.make_obj_array([fiv.get() for fiv in fld_in_vol])

        #fplot.show_scalar_in_mayavi(fld_in_vol.real, max_val=5)
        fplot.write_vtk_file("potential.vts", [
            ("potential", fld_in_vol[0]),
            ("grad", fld_in_vol[1:]),
        ])
Пример #17
0
def draw_2d_mesh(mesh, draw_vertex_numbers=True, draw_element_numbers=True,
        draw_connectivity=False, set_bounding_box=False, **kwargs):
    assert mesh.ambient_dim == 2

    import matplotlib.pyplot as pt
    import matplotlib.patches as mpatches
    from matplotlib.path import Path

    for igrp, grp in enumerate(mesh.groups):
        for iel, el in enumerate(grp.vertex_indices):
            elverts = mesh.vertices[:, el]

            pathdata = [
                (Path.MOVETO, (elverts[0, 0], elverts[1, 0])),
                ]
            for i in range(1, elverts.shape[1]):
                pathdata.append(
                    (Path.LINETO, (elverts[0, i], elverts[1, i]))
                    )
            pathdata.append(
                (Path.CLOSEPOLY, (elverts[0, 0], elverts[1, 0])))

            codes, verts = zip(*pathdata)
            path = Path(verts, codes)
            patch = mpatches.PathPatch(path, **kwargs)
            pt.gca().add_patch(patch)

            if draw_element_numbers:
                centroid = (np.sum(elverts, axis=1) / elverts.shape[1])

                if len(mesh.groups) == 1:
                    el_label = str(iel)
                else:
                    el_label = "%d:%d" % (igrp, iel)

                pt.text(centroid[0], centroid[1], el_label, fontsize=17,
                        ha="center", va="center",
                        bbox=dict(facecolor='white', alpha=0.5, lw=0))

    if draw_vertex_numbers:
        for ivert, vert in enumerate(mesh.vertices.T):
            pt.text(vert[0], vert[1], str(ivert), fontsize=15,
                    ha="center", va="center", color="blue",
                    bbox=dict(facecolor='white', alpha=0.5, lw=0))

    if draw_connectivity:
        def global_iel_to_group_and_iel(global_iel):
            for igrp, grp in enumerate(mesh.groups):
                if global_iel < grp.nelements:
                    return grp, global_iel
                global_iel -= grp.nelements

            raise ValueError("invalid element nr")

        cnx = mesh.element_connectivity

        nb_starts = cnx.neighbors_starts
        for iel_g in range(mesh.nelements):
            for nb_iel_g in cnx.neighbors[nb_starts[iel_g]:nb_starts[iel_g+1]]:
                assert iel_g != nb_iel_g

                grp, iel = global_iel_to_group_and_iel(iel_g)
                nb_grp, nb_iel = global_iel_to_group_and_iel(nb_iel_g)

                elverts = mesh.vertices[:, grp.vertex_indices[iel]]
                nb_elverts = mesh.vertices[:, nb_grp.vertex_indices[nb_iel]]

                centroid = (np.sum(elverts, axis=1) / elverts.shape[1])
                nb_centroid = (np.sum(nb_elverts, axis=1) / nb_elverts.shape[1])

                dx = nb_centroid - centroid
                start = centroid + 0.15*dx

                mag = np.max(np.abs(dx))
                start += 0.05*(np.random.rand(2)-0.5)*mag
                dx += 0.05*(np.random.rand(2)-0.5)*mag

                pt.arrow(start[0], start[1], 0.7*dx[0], 0.7*dx[1],
                        length_includes_head=True,
                        color="green", head_width=1e-2, lw=1e-2)

    if set_bounding_box:
        from meshmode.mesh.processing import find_bounding_box
        lower, upper = find_bounding_box(mesh)
        pt.xlim([lower[0], upper[0]])
        pt.ylim([lower[1], upper[1]])
Пример #18
0
def run_exterior_stokes(
        ctx_factory,
        *,
        ambient_dim,
        target_order,
        qbx_order,
        resolution,
        fmm_order=False,  # FIXME: FMM is slower than direct evaluation
        source_ovsmp=None,
        radius=1.5,
        mu=1.0,
        visualize=False,
        _target_association_tolerance=0.05,
        _expansions_in_tree_have_extent=True):
    cl_ctx = cl.create_some_context()
    queue = cl.CommandQueue(cl_ctx)
    actx = PyOpenCLArrayContext(queue)

    # {{{ geometry

    if source_ovsmp is None:
        source_ovsmp = 4 if ambient_dim == 2 else 8

    places = {}

    if ambient_dim == 2:
        from meshmode.mesh.generation import make_curve_mesh, ellipse
        mesh = make_curve_mesh(lambda t: radius * ellipse(1.0, t),
                               np.linspace(0.0, 1.0, resolution + 1),
                               target_order)
    elif ambient_dim == 3:
        from meshmode.mesh.generation import generate_icosphere
        mesh = generate_icosphere(radius,
                                  target_order + 1,
                                  uniform_refinement_rounds=resolution)
    else:
        raise ValueError(f"unsupported dimension: {ambient_dim}")

    pre_density_discr = Discretization(
        actx, mesh, InterpolatoryQuadratureSimplexGroupFactory(target_order))

    from pytential.qbx import QBXLayerPotentialSource
    qbx = QBXLayerPotentialSource(
        pre_density_discr,
        fine_order=source_ovsmp * target_order,
        qbx_order=qbx_order,
        fmm_order=fmm_order,
        target_association_tolerance=_target_association_tolerance,
        _expansions_in_tree_have_extent=_expansions_in_tree_have_extent)
    places["source"] = qbx

    from extra_int_eq_data import make_source_and_target_points
    point_source, point_target = make_source_and_target_points(
        side=+1,
        inner_radius=0.5 * radius,
        outer_radius=2.0 * radius,
        ambient_dim=ambient_dim,
    )
    places["point_source"] = point_source
    places["point_target"] = point_target

    if visualize:
        from sumpy.visualization import make_field_plotter_from_bbox
        from meshmode.mesh.processing import find_bounding_box
        fplot = make_field_plotter_from_bbox(find_bounding_box(mesh),
                                             h=0.1,
                                             extend_factor=1.0)
        mask = np.linalg.norm(fplot.points, ord=2, axis=0) > (radius + 0.25)

        from pytential.target import PointsTarget
        plot_target = PointsTarget(fplot.points[:, mask].copy())
        places["plot_target"] = plot_target

        del mask

    places = GeometryCollection(places, auto_where="source")

    density_discr = places.get_discretization("source")
    logger.info("ndofs:     %d", density_discr.ndofs)
    logger.info("nelements: %d", density_discr.mesh.nelements)

    # }}}

    # {{{ symbolic

    sym_normal = sym.make_sym_vector("normal", ambient_dim)
    sym_mu = sym.var("mu")

    if ambient_dim == 2:
        from pytential.symbolic.stokes import HsiaoKressExteriorStokesOperator
        sym_omega = sym.make_sym_vector("omega", ambient_dim)
        op = HsiaoKressExteriorStokesOperator(omega=sym_omega)
    elif ambient_dim == 3:
        from pytential.symbolic.stokes import HebekerExteriorStokesOperator
        op = HebekerExteriorStokesOperator()
    else:
        assert False

    sym_sigma = op.get_density_var("sigma")
    sym_bc = op.get_density_var("bc")

    sym_op = op.operator(sym_sigma, normal=sym_normal, mu=sym_mu)
    sym_rhs = op.prepare_rhs(sym_bc, mu=mu)

    sym_velocity = op.velocity(sym_sigma, normal=sym_normal, mu=sym_mu)

    sym_source_pot = op.stokeslet.apply(sym_sigma,
                                        sym_mu,
                                        qbx_forced_limit=None)

    # }}}

    # {{{ boundary conditions

    normal = bind(places, sym.normal(ambient_dim).as_vector())(actx)

    np.random.seed(42)
    charges = make_obj_array([
        actx.from_numpy(np.random.randn(point_source.ndofs))
        for _ in range(ambient_dim)
    ])

    if ambient_dim == 2:
        total_charge = make_obj_array([actx.np.sum(c) for c in charges])
        omega = bind(places, total_charge * sym.Ones())(actx)

    if ambient_dim == 2:
        bc_context = {"mu": mu, "omega": omega}
        op_context = {"mu": mu, "omega": omega, "normal": normal}
    else:
        bc_context = {}
        op_context = {"mu": mu, "normal": normal}

    bc = bind(places, sym_source_pot,
              auto_where=("point_source", "source"))(actx,
                                                     sigma=charges,
                                                     mu=mu)

    rhs = bind(places, sym_rhs)(actx, bc=bc, **bc_context)
    bound_op = bind(places, sym_op)

    # }}}

    # {{{ solve

    from pytential.solve import gmres
    gmres_tol = 1.0e-9
    result = gmres(bound_op.scipy_op(actx, "sigma", np.float64, **op_context),
                   rhs,
                   x0=rhs,
                   tol=gmres_tol,
                   progress=visualize,
                   stall_iterations=0,
                   hard_failure=True)

    sigma = result.solution

    # }}}

    # {{{ check velocity at "point_target"

    def rnorm2(x, y):
        y_norm = actx.np.linalg.norm(y.dot(y), ord=2)
        if y_norm < 1.0e-14:
            y_norm = 1.0

        d = x - y
        return actx.np.linalg.norm(d.dot(d), ord=2) / y_norm

    ps_velocity = bind(places,
                       sym_velocity,
                       auto_where=("source", "point_target"))(actx,
                                                              sigma=sigma,
                                                              **op_context)
    ex_velocity = bind(places,
                       sym_source_pot,
                       auto_where=("point_source",
                                   "point_target"))(actx, sigma=charges, mu=mu)

    v_error = rnorm2(ps_velocity, ex_velocity)
    h_max = bind(places, sym.h_max(ambient_dim))(actx)

    logger.info("resolution %4d h_max %.5e error %.5e", resolution, h_max,
                v_error)

    # }}}}

    # {{{ visualize

    if not visualize:
        return h_max, v_error

    from meshmode.discretization.visualization import make_visualizer
    vis = make_visualizer(actx, density_discr, target_order)

    filename = "stokes_solution_{}d_{}_ovsmp_{}.vtu".format(
        ambient_dim, resolution, source_ovsmp)

    vis.write_vtk_file(filename, [
        ("density", sigma),
        ("bc", bc),
        ("rhs", rhs),
    ],
                       overwrite=True)

    # }}}

    return h_max, v_error
Пример #19
0
def test_refinement_connection(
        ctx_getter, refiner_cls, group_factory,
        mesh_name, dim, mesh_pars, mesh_order, refine_flags, visualize=False):
    from random import seed
    seed(13)

    # Discretization order
    order = 5

    cl_ctx = ctx_getter()
    queue = cl.CommandQueue(cl_ctx)

    from meshmode.discretization import Discretization
    from meshmode.discretization.connection import (
            make_refinement_connection, check_connection)

    from pytools.convergence import EOCRecorder
    eoc_rec = EOCRecorder()

    for mesh_par in mesh_pars:
        # {{{ get mesh

        if mesh_name == "circle":
            assert dim == 1
            h = 1 / mesh_par
            mesh = make_curve_mesh(
                partial(ellipse, 1), np.linspace(0, 1, mesh_par + 1),
                order=mesh_order)
        elif mesh_name == "blob":
            if mesh_order == 5:
                pytest.xfail("https://gitlab.tiker.net/inducer/meshmode/issues/2")
            assert dim == 2
            mesh = get_blob_mesh(mesh_par, mesh_order)
            h = float(mesh_par)
        elif mesh_name == "warp":
            from meshmode.mesh.generation import generate_warped_rect_mesh
            mesh = generate_warped_rect_mesh(dim, order=mesh_order, n=mesh_par)
            h = 1/mesh_par
        else:
            raise ValueError("mesh_name not recognized")

        # }}}

        from meshmode.mesh.processing import find_bounding_box
        mesh_bbox_low, mesh_bbox_high = find_bounding_box(mesh)
        mesh_ext = mesh_bbox_high-mesh_bbox_low

        def f(x):
            result = 1
            if mesh_name == "blob":
                factor = 15
            else:
                factor = 9

            for iaxis in range(len(x)):
                result = result * cl.clmath.sin(factor * (x[iaxis]/mesh_ext[iaxis]))

            return result

        discr = Discretization(cl_ctx, mesh, group_factory(order))

        refiner = refiner_cls(mesh)
        flags = refine_flags(mesh)
        refiner.refine(flags)

        connection = make_refinement_connection(
            refiner, discr, group_factory(order))
        check_connection(connection)

        fine_discr = connection.to_discr

        x = discr.nodes().with_queue(queue)
        x_fine = fine_discr.nodes().with_queue(queue)
        f_coarse = f(x)
        f_interp = connection(queue, f_coarse).with_queue(queue)
        f_true = f(x_fine).with_queue(queue)

        if visualize == "dots":
            import matplotlib.pyplot as plt
            x = x.get(queue)
            err = np.array(np.log10(
                1e-16 + np.abs((f_interp - f_true).get(queue))), dtype=float)
            import matplotlib.cm as cm
            cmap = cm.ScalarMappable(cmap=cm.jet)
            cmap.set_array(err)
            plt.scatter(x[0], x[1], c=cmap.to_rgba(err), s=20, cmap=cmap)
            plt.colorbar(cmap)
            plt.show()

        elif visualize == "vtk":
            from meshmode.discretization.visualization import make_visualizer
            fine_vis = make_visualizer(queue, fine_discr, mesh_order)

            fine_vis.write_vtk_file(
                    "refine-fine-%s-%dd-%s.vtu" % (mesh_name, dim, mesh_par), [
                        ("f_interp", f_interp),
                        ("f_true", f_true),
                        ])

        import numpy.linalg as la
        err = la.norm((f_interp - f_true).get(queue), np.inf)
        eoc_rec.add_data_point(h, err)

    order_slack = 0.5
    if mesh_name == "blob" and order > 1:
        order_slack = 1

    print(eoc_rec)
    assert (
            eoc_rec.order_estimate() >= order-order_slack
            or eoc_rec.max_error() < 1e-14)
Пример #20
0
def main(mesh_name="ellipsoid"):
    import logging
    logger = logging.getLogger(__name__)
    logging.basicConfig(level=logging.WARNING)  # INFO for more progress info

    cl_ctx = cl.create_some_context()
    queue = cl.CommandQueue(cl_ctx)
    actx = PyOpenCLArrayContext(queue)

    if mesh_name == "ellipsoid":
        cad_file_name = "geometries/ellipsoid.step"
        h = 0.6
    elif mesh_name == "two-cylinders":
        cad_file_name = "geometries/two-cylinders-smooth.step"
        h = 0.4
    else:
        raise ValueError("unknown mesh name: %s" % mesh_name)

    from meshmode.mesh.io import generate_gmsh, FileSource
    mesh = generate_gmsh(
        FileSource(cad_file_name),
        2,
        order=2,
        other_options=["-string",
                       "Mesh.CharacteristicLengthMax = %g;" % h],
        target_unit="MM")

    from meshmode.mesh.processing import perform_flips
    # Flip elements--gmsh generates inside-out geometry.
    mesh = perform_flips(mesh, np.ones(mesh.nelements))

    from meshmode.mesh.processing import find_bounding_box
    bbox_min, bbox_max = find_bounding_box(mesh)
    bbox_center = 0.5 * (bbox_min + bbox_max)
    bbox_size = max(bbox_max - bbox_min) / 2

    logger.info("%d elements" % mesh.nelements)

    from pytential.qbx import QBXLayerPotentialSource
    from meshmode.discretization import Discretization
    from meshmode.discretization.poly_element import \
            InterpolatoryQuadratureSimplexGroupFactory

    density_discr = Discretization(
        actx, mesh, InterpolatoryQuadratureSimplexGroupFactory(target_order))

    qbx = QBXLayerPotentialSource(density_discr,
                                  4 * target_order,
                                  qbx_order,
                                  fmm_order=qbx_order + 3,
                                  target_association_tolerance=0.15)

    from pytential.target import PointsTarget
    fplot = FieldPlotter(bbox_center, extent=3.5 * bbox_size, npoints=150)

    from pytential import GeometryCollection
    places = GeometryCollection(
        {
            "qbx": qbx,
            "targets": PointsTarget(fplot.points)
        }, auto_where="qbx")
    density_discr = places.get_discretization("qbx")

    nodes = thaw(actx, density_discr.nodes())
    angle = actx.np.arctan2(nodes[1], nodes[0])

    if k:
        kernel = HelmholtzKernel(3)
    else:
        kernel = LaplaceKernel(3)

    #op = sym.d_dx(sym.S(kernel, sym.var("sigma"), qbx_forced_limit=None))
    op = sym.D(kernel, sym.var("sigma"), qbx_forced_limit=None)
    #op = sym.S(kernel, sym.var("sigma"), qbx_forced_limit=None)

    sigma = actx.np.cos(mode_nr * angle)
    if 0:
        from meshmode.dof_array import flatten, unflatten
        sigma = flatten(0 * angle)
        from random import randrange
        for i in range(5):
            sigma[randrange(len(sigma))] = 1
        sigma = unflatten(actx, density_discr, sigma)

    if isinstance(kernel, HelmholtzKernel):
        for i, elem in np.ndenumerate(sigma):
            sigma[i] = elem.astype(np.complex128)

    fld_in_vol = actx.to_numpy(
        bind(places, op, auto_where=("qbx", "targets"))(actx, sigma=sigma,
                                                        k=k))

    #fplot.show_scalar_in_mayavi(fld_in_vol.real, max_val=5)
    fplot.write_vtk_file("layerpot-3d-potential.vts",
                         [("potential", fld_in_vol)])

    bdry_normals = bind(places, sym.normal(
        density_discr.ambient_dim))(actx).as_vector(dtype=object)

    from meshmode.discretization.visualization import make_visualizer
    bdry_vis = make_visualizer(actx, density_discr, target_order)
    bdry_vis.write_vtk_file("layerpot-3d-density.vtu", [
        ("sigma", sigma),
        ("bdry_normals", bdry_normals),
    ])
Пример #21
0
                                       case.target_order + 3)

            bdry_normals = bind(scat_discr, sym.normal(3))(queue)\
                    .as_vector(dtype=object)

            bdry_vis.write_vtk_file("source-%s.vtu" % resolution, [
                ("j", jxyz),
                ("rho", rho),
                ("Einc", inc_field_scat.e),
                ("Hinc", inc_field_scat.h),
                ("bdry_normals", bdry_normals),
                ("e_bc_residual", eh_bc_values[:3]),
                ("h_bc_residual", eh_bc_values[3]),
            ])

            fplot = make_field_plotter_from_bbox(find_bounding_box(
                scat_discr.mesh),
                                                 h=(0.05, 0.05, 0.3),
                                                 extend_factor=0.3)

            from pytential.qbx import QBXTargetAssociationFailedException

            qbx_tgt_tol = qbx.copy(target_association_tolerance=0.2)

            fplot_tgt = PointsTarget(cl.array.to_device(queue, fplot.points))
            try:
                fplot_repr = eval_repr_at(fplot_tgt, source=qbx_tgt_tol)
            except QBXTargetAssociationFailedException as e:
                fplot.write_vtk_file(
                    "failed-targets.vts",
                    [("failed_targets", e.failed_target_flags.get(queue))])
                raise
Пример #22
0
def run_int_eq_test(cl_ctx, queue, case, resolution, visualize):
    mesh = case.get_mesh(resolution, case.target_order)
    print("%d elements" % mesh.nelements)

    from pytential.qbx import QBXLayerPotentialSource
    from meshmode.discretization import Discretization
    from meshmode.discretization.poly_element import \
            InterpolatoryQuadratureSimplexGroupFactory
    pre_density_discr = Discretization(
            cl_ctx, mesh,
            InterpolatoryQuadratureSimplexGroupFactory(case.target_order))

    source_order = 4*case.target_order

    refiner_extra_kwargs = {}

    qbx_lpot_kwargs = {}
    if case.fmm_backend is None:
        qbx_lpot_kwargs["fmm_order"] = False
    else:
        if hasattr(case, "fmm_tol"):
            from sumpy.expansion.level_to_order import SimpleExpansionOrderFinder
            qbx_lpot_kwargs["fmm_level_to_order"] = SimpleExpansionOrderFinder(
                    case.fmm_tol)

        elif hasattr(case, "fmm_order"):
            qbx_lpot_kwargs["fmm_order"] = case.fmm_order
        else:
            qbx_lpot_kwargs["fmm_order"] = case.qbx_order + 5

    qbx = QBXLayerPotentialSource(
            pre_density_discr,
            fine_order=source_order,
            qbx_order=case.qbx_order,

            _box_extent_norm=getattr(case, "box_extent_norm", None),
            _from_sep_smaller_crit=getattr(case, "from_sep_smaller_crit", None),
            _from_sep_smaller_min_nsources_cumul=30,
            fmm_backend=case.fmm_backend, **qbx_lpot_kwargs)

    if case.use_refinement:
        if case.k != 0 and getattr(case, "refine_on_helmholtz_k", True):
            refiner_extra_kwargs["kernel_length_scale"] = 5/case.k

        if hasattr(case, "scaled_max_curvature_threshold"):
            refiner_extra_kwargs["_scaled_max_curvature_threshold"] = \
                    case.scaled_max_curvature_threshold

        if hasattr(case, "expansion_disturbance_tolerance"):
            refiner_extra_kwargs["_expansion_disturbance_tolerance"] = \
                    case.expansion_disturbance_tolerance

        if hasattr(case, "refinement_maxiter"):
            refiner_extra_kwargs["maxiter"] = case.refinement_maxiter

        #refiner_extra_kwargs["visualize"] = True

        print("%d elements before refinement" % pre_density_discr.mesh.nelements)
        qbx, _ = qbx.with_refinement(**refiner_extra_kwargs)
        print("%d stage-1 elements after refinement"
                % qbx.density_discr.mesh.nelements)
        print("%d stage-2 elements after refinement"
                % qbx.stage2_density_discr.mesh.nelements)
        print("quad stage-2 elements have %d nodes"
                % qbx.quad_stage2_density_discr.groups[0].nunit_nodes)

    density_discr = qbx.density_discr

    if hasattr(case, "visualize_geometry") and case.visualize_geometry:
        bdry_normals = bind(
                density_discr, sym.normal(mesh.ambient_dim)
                )(queue).as_vector(dtype=object)

        bdry_vis = make_visualizer(queue, density_discr, case.target_order)
        bdry_vis.write_vtk_file("geometry.vtu", [
            ("normals", bdry_normals)
            ])

    # {{{ plot geometry

    if 0:
        if mesh.ambient_dim == 2:
            # show geometry, centers, normals
            nodes_h = density_discr.nodes().get(queue=queue)
            pt.plot(nodes_h[0], nodes_h[1], "x-")
            normal = bind(density_discr, sym.normal(2))(queue).as_vector(np.object)
            pt.quiver(nodes_h[0], nodes_h[1],
                    normal[0].get(queue), normal[1].get(queue))
            pt.gca().set_aspect("equal")
            pt.show()

        elif mesh.ambient_dim == 3:
            bdry_vis = make_visualizer(queue, density_discr, case.target_order+3)

            bdry_normals = bind(density_discr, sym.normal(3))(queue)\
                    .as_vector(dtype=object)

            bdry_vis.write_vtk_file("pre-solve-source-%s.vtu" % resolution, [
                ("bdry_normals", bdry_normals),
                ])

        else:
            raise ValueError("invalid mesh dim")

    # }}}

    # {{{ set up operator

    from pytential.symbolic.pde.scalar import (
            DirichletOperator,
            NeumannOperator)

    from sumpy.kernel import LaplaceKernel, HelmholtzKernel
    if case.k:
        knl = HelmholtzKernel(mesh.ambient_dim)
        knl_kwargs = {"k": sym.var("k")}
        concrete_knl_kwargs = {"k": case.k}
    else:
        knl = LaplaceKernel(mesh.ambient_dim)
        knl_kwargs = {}
        concrete_knl_kwargs = {}

    if knl.is_complex_valued:
        dtype = np.complex128
    else:
        dtype = np.float64

    loc_sign = +1 if case.prob_side in [+1, "scat"] else -1

    if case.bc_type == "dirichlet":
        op = DirichletOperator(knl, loc_sign, use_l2_weighting=True,
                kernel_arguments=knl_kwargs)
    elif case.bc_type == "neumann":
        op = NeumannOperator(knl, loc_sign, use_l2_weighting=True,
                 use_improved_operator=False, kernel_arguments=knl_kwargs)
    else:
        assert False

    op_u = op.operator(sym.var("u"))

    # }}}

    # {{{ set up test data

    if case.prob_side == -1:
        test_src_geo_radius = case.outer_radius
        test_tgt_geo_radius = case.inner_radius
    elif case.prob_side == +1:
        test_src_geo_radius = case.inner_radius
        test_tgt_geo_radius = case.outer_radius
    elif case.prob_side == "scat":
        test_src_geo_radius = case.outer_radius
        test_tgt_geo_radius = case.outer_radius
    else:
        raise ValueError("unknown problem_side")

    point_sources = make_circular_point_group(
            mesh.ambient_dim, 10, test_src_geo_radius,
            func=lambda x: x**1.5)
    test_targets = make_circular_point_group(
            mesh.ambient_dim, 20, test_tgt_geo_radius)

    np.random.seed(22)
    source_charges = np.random.randn(point_sources.shape[1])
    source_charges[-1] = -np.sum(source_charges[:-1])
    source_charges = source_charges.astype(dtype)
    assert np.sum(source_charges) < 1e-15

    source_charges_dev = cl.array.to_device(queue, source_charges)

    # }}}

    # {{{ establish BCs

    from pytential.source import PointPotentialSource
    from pytential.target import PointsTarget

    point_source = PointPotentialSource(cl_ctx, point_sources)

    pot_src = sym.IntG(
        # FIXME: qbx_forced_limit--really?
        knl, sym.var("charges"), qbx_forced_limit=None, **knl_kwargs)

    test_direct = bind((point_source, PointsTarget(test_targets)), pot_src)(
            queue, charges=source_charges_dev, **concrete_knl_kwargs)

    if case.bc_type == "dirichlet":
        bc = bind((point_source, density_discr), pot_src)(
                queue, charges=source_charges_dev, **concrete_knl_kwargs)

    elif case.bc_type == "neumann":
        bc = bind(
                (point_source, density_discr),
                sym.normal_derivative(
                    qbx.ambient_dim, pot_src, where=sym.DEFAULT_TARGET)
                )(queue, charges=source_charges_dev, **concrete_knl_kwargs)

    # }}}

    # {{{ solve

    bound_op = bind(qbx, op_u)

    rhs = bind(density_discr, op.prepare_rhs(sym.var("bc")))(queue, bc=bc)

    try:
        from pytential.solve import gmres
        gmres_result = gmres(
                bound_op.scipy_op(queue, "u", dtype, **concrete_knl_kwargs),
                rhs,
                tol=case.gmres_tol,
                progress=True,
                hard_failure=True,
                stall_iterations=50, no_progress_factor=1.05)
    except QBXTargetAssociationFailedException as e:
        bdry_vis = make_visualizer(queue, density_discr, case.target_order+3)

        bdry_vis.write_vtk_file("failed-targets-%s.vtu" % resolution, [
            ("failed_targets", e.failed_target_flags),
            ])
        raise

    print("gmres state:", gmres_result.state)
    weighted_u = gmres_result.solution

    # }}}

    # {{{ build matrix for spectrum check

    if 0:
        from sumpy.tools import build_matrix
        mat = build_matrix(
                bound_op.scipy_op(
                    queue, arg_name="u", dtype=dtype, k=case.k))
        w, v = la.eig(mat)
        if 0:
            pt.imshow(np.log10(1e-20+np.abs(mat)))
            pt.colorbar()
            pt.show()

        #assert abs(s[-1]) < 1e-13, "h
        #assert abs(s[-2]) > 1e-7
        #from pudb import set_trace; set_trace()

    # }}}

    if case.prob_side != "scat":
        # {{{ error check

        points_target = PointsTarget(test_targets)
        bound_tgt_op = bind((qbx, points_target),
                op.representation(sym.var("u")))

        test_via_bdry = bound_tgt_op(queue, u=weighted_u, k=case.k)

        err = test_via_bdry - test_direct

        err = err.get()
        test_direct = test_direct.get()
        test_via_bdry = test_via_bdry.get()

        # {{{ remove effect of net source charge

        if case.k == 0 and case.bc_type == "neumann" and loc_sign == -1:

            # remove constant offset in interior Laplace Neumann error
            tgt_ones = np.ones_like(test_direct)
            tgt_ones = tgt_ones/la.norm(tgt_ones)
            err = err - np.vdot(tgt_ones, err)*tgt_ones

        # }}}

        rel_err_2 = la.norm(err)/la.norm(test_direct)
        rel_err_inf = la.norm(err, np.inf)/la.norm(test_direct, np.inf)

        # }}}

        print("rel_err_2: %g rel_err_inf: %g" % (rel_err_2, rel_err_inf))

    else:
        rel_err_2 = None
        rel_err_inf = None

    # {{{ test gradient

    if case.check_gradient and case.prob_side != "scat":
        bound_grad_op = bind((qbx, points_target),
                op.representation(
                    sym.var("u"),
                    map_potentials=lambda pot: sym.grad(mesh.ambient_dim, pot),
                    qbx_forced_limit=None))

        #print(bound_t_deriv_op.code)

        grad_from_src = bound_grad_op(
                queue, u=weighted_u, **concrete_knl_kwargs)

        grad_ref = (bind(
                (point_source, points_target),
                sym.grad(mesh.ambient_dim, pot_src)
                )(queue, charges=source_charges_dev, **concrete_knl_kwargs)
                )

        grad_err = (grad_from_src - grad_ref)

        rel_grad_err_inf = (
                la.norm(grad_err[0].get(), np.inf)
                / la.norm(grad_ref[0].get(), np.inf))

        print("rel_grad_err_inf: %g" % rel_grad_err_inf)

    # }}}

    # {{{ test tangential derivative

    if case.check_tangential_deriv and case.prob_side != "scat":
        bound_t_deriv_op = bind(qbx,
                op.representation(
                    sym.var("u"),
                    map_potentials=lambda pot: sym.tangential_derivative(2, pot),
                    qbx_forced_limit=loc_sign))

        #print(bound_t_deriv_op.code)

        tang_deriv_from_src = bound_t_deriv_op(
                queue, u=weighted_u, **concrete_knl_kwargs).as_scalar().get()

        tang_deriv_ref = (bind(
                (point_source, density_discr),
                sym.tangential_derivative(2, pot_src)
                )(queue, charges=source_charges_dev, **concrete_knl_kwargs)
                .as_scalar().get())

        if 0:
            pt.plot(tang_deriv_ref.real)
            pt.plot(tang_deriv_from_src.real)
            pt.show()

        td_err = (tang_deriv_from_src - tang_deriv_ref)

        rel_td_err_inf = la.norm(td_err, np.inf)/la.norm(tang_deriv_ref, np.inf)

        print("rel_td_err_inf: %g" % rel_td_err_inf)

    else:
        rel_td_err_inf = None

    # }}}

    # {{{ any-D file plotting

    if visualize:
        bdry_vis = make_visualizer(queue, density_discr, case.target_order+3)

        bdry_normals = bind(density_discr, sym.normal(qbx.ambient_dim))(queue)\
                .as_vector(dtype=object)

        sym_sqrt_j = sym.sqrt_jac_q_weight(density_discr.ambient_dim)
        u = bind(density_discr, sym.var("u")/sym_sqrt_j)(queue, u=weighted_u)

        bdry_vis.write_vtk_file("source-%s.vtu" % resolution, [
            ("u", u),
            ("bc", bc),
            #("bdry_normals", bdry_normals),
            ])

        from sumpy.visualization import make_field_plotter_from_bbox  # noqa
        from meshmode.mesh.processing import find_bounding_box

        vis_grid_spacing = (0.1, 0.1, 0.1)[:qbx.ambient_dim]
        if hasattr(case, "vis_grid_spacing"):
            vis_grid_spacing = case.vis_grid_spacing
        vis_extend_factor = 0.2
        if hasattr(case, "vis_extend_factor"):
            vis_grid_spacing = case.vis_grid_spacing

        fplot = make_field_plotter_from_bbox(
                find_bounding_box(mesh),
                h=vis_grid_spacing,
                extend_factor=vis_extend_factor)

        qbx_tgt_tol = qbx.copy(target_association_tolerance=0.15)
        from pytential.target import PointsTarget

        try:
            solved_pot = bind(
                    (qbx_tgt_tol, PointsTarget(fplot.points)),
                    op.representation(sym.var("u"))
                    )(queue, u=weighted_u, k=case.k)
        except QBXTargetAssociationFailedException as e:
            fplot.write_vtk_file(
                    "failed-targets.vts",
                    [
                        ("failed_targets", e.failed_target_flags.get(queue))
                        ])
            raise

        from sumpy.kernel import LaplaceKernel
        ones_density = density_discr.zeros(queue)
        ones_density.fill(1)
        indicator = bind(
                (qbx_tgt_tol, PointsTarget(fplot.points)),
                -sym.D(LaplaceKernel(density_discr.ambient_dim),
                    sym.var("sigma"),
                    qbx_forced_limit=None))(
                queue, sigma=ones_density).get()

        solved_pot = solved_pot.get()

        true_pot = bind((point_source, PointsTarget(fplot.points)), pot_src)(
                queue, charges=source_charges_dev, **concrete_knl_kwargs).get()

        #fplot.show_scalar_in_mayavi(solved_pot.real, max_val=5)
        if case.prob_side == "scat":
            fplot.write_vtk_file(
                    "potential-%s.vts" % resolution,
                    [
                        ("pot_scattered", solved_pot),
                        ("pot_incoming", -true_pot),
                        ("indicator", indicator),
                        ]
                    )
        else:
            fplot.write_vtk_file(
                    "potential-%s.vts" % resolution,
                    [
                        ("solved_pot", solved_pot),
                        ("true_pot", true_pot),
                        ("indicator", indicator),
                        ]
                    )

    # }}}

    class Result(Record):
        pass

    return Result(
            h_max=qbx.h_max,
            rel_err_2=rel_err_2,
            rel_err_inf=rel_err_inf,
            rel_td_err_inf=rel_td_err_inf,
            gmres_result=gmres_result)
Пример #23
0
h = 0.4

k = 0
if k:
    kernel = HelmholtzKernel("k")
else:
    kernel = LaplaceKernel()
#kernel = OneKernel()

from meshmode.mesh.io import generate_gmsh, FileSource
mesh = generate_gmsh(
        FileSource("molecule.step"), 2, order=2,
        other_options=["-string", "Mesh.CharacteristicLengthMax = %g;" % h])

from meshmode.mesh.processing import find_bounding_box
bbox_min, bbox_max = find_bounding_box(mesh)
bbox_center = 0.5*(bbox_min+bbox_max)
bbox_size = max(bbox_max-bbox_min) / 2

logger.info("%d elements" % mesh.nelements)

from pytential.qbx import QBXLayerPotentialSource
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
        InterpolatoryQuadratureSimplexGroupFactory

density_discr = Discretization(
        cl_ctx, mesh, InterpolatoryQuadratureSimplexGroupFactory(target_order))

qbx = QBXLayerPotentialSource(density_discr, 4*target_order, qbx_order,
        fmm_order=qbx_order)
Пример #24
0
def test_refinement_connection(actx_factory,
                               refiner_cls,
                               group_factory,
                               mesh_name,
                               dim,
                               mesh_pars,
                               mesh_order,
                               refine_flags,
                               visualize=False):
    group_cls = group_factory.mesh_group_class
    if issubclass(group_cls, TensorProductElementGroup):
        if mesh_name in ["circle", "blob"]:
            pytest.skip("mesh does not have tensor product support")

    from random import seed
    seed(13)

    actx = actx_factory()

    # discretization order
    order = 5

    from meshmode.discretization import Discretization
    from meshmode.discretization.connection import (make_refinement_connection,
                                                    check_connection)

    from pytools.convergence import EOCRecorder
    eoc_rec = EOCRecorder()

    for mesh_par in mesh_pars:
        # {{{ get mesh

        if mesh_name == "circle":
            assert dim == 1
            h = 1 / mesh_par
            mesh = make_curve_mesh(partial(ellipse, 1),
                                   np.linspace(0, 1, mesh_par + 1),
                                   order=mesh_order)
        elif mesh_name == "blob":
            if mesh_order == 5:
                pytest.xfail(
                    "https://gitlab.tiker.net/inducer/meshmode/issues/2")
            assert dim == 2
            mesh = get_blob_mesh(mesh_par, mesh_order)
            h = float(mesh_par)
        elif mesh_name == "warp":
            mesh = mgen.generate_warped_rect_mesh(dim,
                                                  order=mesh_order,
                                                  n=mesh_par,
                                                  group_cls=group_cls)
            h = 1 / mesh_par
        else:
            raise ValueError("mesh_name not recognized")

        # }}}

        from meshmode.mesh.processing import find_bounding_box
        mesh_bbox_low, mesh_bbox_high = find_bounding_box(mesh)
        mesh_ext = mesh_bbox_high - mesh_bbox_low

        def f(x):
            result = 1
            if mesh_name == "blob":
                factor = 15
            else:
                factor = 9

            for iaxis in range(len(x)):
                result = result * actx.np.sin(factor *
                                              (x[iaxis] / mesh_ext[iaxis]))

            return result

        discr = Discretization(actx, mesh, group_factory(order))

        refiner = refiner_cls(mesh)
        flags = refine_flags(mesh)
        refiner.refine(flags)

        connection = make_refinement_connection(actx, refiner, discr,
                                                group_factory(order))
        check_connection(actx, connection)

        fine_discr = connection.to_discr

        x = thaw(actx, discr.nodes())
        x_fine = thaw(actx, fine_discr.nodes())
        f_coarse = f(x)
        f_interp = connection(f_coarse)
        f_true = f(x_fine)

        if visualize == "dots":
            import matplotlib.pyplot as plt
            x = x.get(actx.queue)
            err = np.array(
                np.log10(1e-16 + np.abs((f_interp - f_true).get(actx.queue))),
                dtype=float)
            import matplotlib.cm as cm
            cmap = cm.ScalarMappable(cmap=cm.jet)
            cmap.set_array(err)
            plt.scatter(x[0], x[1], c=cmap.to_rgba(err), s=20, cmap=cmap)
            plt.colorbar(cmap)
            plt.show()

        elif visualize == "vtk":
            from meshmode.discretization.visualization import make_visualizer
            fine_vis = make_visualizer(actx, fine_discr, mesh_order)

            fine_vis.write_vtk_file(
                "refine-fine-%s-%dd-%s.vtu" % (mesh_name, dim, mesh_par), [
                    ("f_interp", f_interp),
                    ("f_true", f_true),
                ])

        err = actx.np.linalg.norm(f_interp - f_true, np.inf)
        eoc_rec.add_data_point(h, err)

    order_slack = 0.5
    if mesh_name == "blob" and order > 1:
        order_slack = 1

    print(eoc_rec)
    assert (eoc_rec.order_estimate() >= order - order_slack
            or eoc_rec.max_error() < 1e-14)
Пример #25
0
def check_nodal_adj_against_geometry(mesh, tol=1e-12):
    def group_and_iel_to_global_iel(igrp, iel):
        return mesh.groups[igrp].element_nr_base + iel

    logger.debug("nodal adj test: tree build")
    from meshmode.mesh.tools import make_element_lookup_tree
    tree = make_element_lookup_tree(mesh, eps=tol)
    logger.debug("nodal adj test: tree build done")

    from meshmode.mesh.processing import find_bounding_box
    bbox_min, bbox_max = find_bounding_box(mesh)

    nadj = mesh.nodal_adjacency
    nvertices_per_element = len(mesh.groups[0].vertex_indices[0])

    connected_to_element_geometry = [set() for i in range(mesh.nelements)]
    connected_to_element_connectivity = [set() for i in range(mesh.nelements)]

    for igrp, grp in enumerate(mesh.groups):
        for iel_grp in range(grp.nelements):
            iel_g = group_and_iel_to_global_iel(igrp, iel_grp)
            nb_starts = nadj.neighbors_starts
            for nb_iel_g in nadj.neighbors[nb_starts[iel_g]:nb_starts[iel_g+1]]:
                connected_to_element_connectivity[iel_g].add(nb_iel_g)

            for vertex_index in grp.vertex_indices[iel_grp]:
                vertex = mesh.vertices[:, vertex_index]

                # check which elements touch this vertex
                for nearby_igrp, nearby_iel in tree.generate_matches(vertex):
                    if nearby_igrp == igrp and nearby_iel == iel_grp:
                        continue
                    nearby_grp = mesh.groups[nearby_igrp]

                    nearby_origin_vertex = mesh.vertices[
                            :, nearby_grp.vertex_indices[nearby_iel][0]]  # noqa
                    transformation = np.empty(
                            (len(mesh.vertices), nvertices_per_element-1))
                    vertex_transformed = vertex - nearby_origin_vertex

                    for inearby_vertex_index, nearby_vertex_index in enumerate(
                            nearby_grp.vertex_indices[nearby_iel][1:]):
                        nearby_vertex = mesh.vertices[:, nearby_vertex_index]
                        transformation[:, inearby_vertex_index] = \
                                nearby_vertex - nearby_origin_vertex
                    bary_coord, residual = \
                            np.linalg.lstsq(transformation, vertex_transformed)[0:2]

                    is_in_element_span = (
                            residual.size == 0
                            or np.linalg.norm(vertex_transformed) == 0
                            or (np.linalg.norm(residual)
                                / np.linalg.norm(vertex_transformed)) <= tol)

                    is_connected = (
                            is_in_element_span
                            and np.sum(bary_coord) <= 1+tol
                            and (bary_coord >= -tol).all())
                    el1 = group_and_iel_to_global_iel(nearby_igrp, nearby_iel)
                    el2 = group_and_iel_to_global_iel(igrp, iel_grp)

                    if is_connected:
                        connected_to_element_geometry[el1].add(el2)
                        connected_to_element_geometry[el2].add(el1)

    assert is_symmetric(connected_to_element_connectivity, debug=True)

    # The geometric adjacency relation isn't necessary symmetric:
    #
    #        /|
    #       / |
    #      /  |\
    #    B \  |/  A
    #       \ |
    #        \|
    #
    # Element A will see element B (its vertices are near B) but not the other
    # way around.

    assert connected_to_element_geometry == connected_to_element_connectivity
Пример #26
0
def check_nodal_adj_against_geometry(mesh, tol=1e-12):
    def group_and_iel_to_global_iel(igrp, iel):
        return mesh.groups[igrp].element_nr_base + iel

    logger.debug("nodal adj test: tree build")
    from meshmode.mesh.tools import make_element_lookup_tree
    tree = make_element_lookup_tree(mesh, eps=tol)
    logger.debug("nodal adj test: tree build done")

    from meshmode.mesh.processing import find_bounding_box
    bbox_min, bbox_max = find_bounding_box(mesh)

    nadj = mesh.nodal_adjacency
    nvertices_per_element = len(mesh.groups[0].vertex_indices[0])

    connected_to_element_geometry = [set() for i in range(mesh.nelements)]
    connected_to_element_connectivity = [set() for i in range(mesh.nelements)]

    for igrp, grp in enumerate(mesh.groups):
        for iel_grp in range(grp.nelements):
            iel_g = group_and_iel_to_global_iel(igrp, iel_grp)
            nb_starts = nadj.neighbors_starts
            for nb_iel_g in nadj.neighbors[nb_starts[iel_g]:nb_starts[iel_g +
                                                                      1]]:
                connected_to_element_connectivity[iel_g].add(nb_iel_g)

            for vertex_index in grp.vertex_indices[iel_grp]:
                vertex = mesh.vertices[:, vertex_index]

                # check which elements touch this vertex
                for nearby_igrp, nearby_iel in tree.generate_matches(vertex):
                    if nearby_igrp == igrp and nearby_iel == iel_grp:
                        continue
                    nearby_grp = mesh.groups[nearby_igrp]

                    nearby_origin_vertex = mesh.vertices[:, nearby_grp.
                                                         vertex_indices[
                                                             nearby_iel]
                                                         [0]]  # noqa
                    transformation = np.empty(
                        (len(mesh.vertices), nvertices_per_element - 1))
                    vertex_transformed = vertex - nearby_origin_vertex

                    for inearby_vertex_index, nearby_vertex_index in enumerate(
                            nearby_grp.vertex_indices[nearby_iel][1:]):
                        nearby_vertex = mesh.vertices[:, nearby_vertex_index]
                        transformation[:, inearby_vertex_index] = \
                                nearby_vertex - nearby_origin_vertex
                    bary_coord, residual = \
                            np.linalg.lstsq(transformation, vertex_transformed)[0:2]

                    is_in_element_span = (
                        residual.size == 0
                        or np.linalg.norm(vertex_transformed) == 0
                        or (np.linalg.norm(residual) /
                            np.linalg.norm(vertex_transformed)) <= tol)

                    is_connected = (is_in_element_span
                                    and np.sum(bary_coord) <= 1 + tol
                                    and (bary_coord >= -tol).all())
                    el1 = group_and_iel_to_global_iel(nearby_igrp, nearby_iel)
                    el2 = group_and_iel_to_global_iel(igrp, iel_grp)

                    if is_connected:
                        connected_to_element_geometry[el1].add(el2)
                        connected_to_element_geometry[el2].add(el1)

    assert is_symmetric(connected_to_element_connectivity, debug=True)

    # The geometric adjacency relation isn't necessary symmetric:
    #
    #        /|
    #       / |
    #      /  |\
    #    B \  |/  A
    #       \ |
    #        \|
    #
    # Element A will see element B (its vertices are near B) but not the other
    # way around.

    assert connected_to_element_geometry == connected_to_element_connectivity
Пример #27
0
                InterpolatoryQuadratureSimplexGroupFactory(case.target_order))

        places.update({
            sym.DEFAULT_SOURCE: qbx,
            sym.DEFAULT_TARGET: qbx.density_discr,
            "test_source": test_source,
            "scat_discr": scat_discr,
            "obs_discr": obs_discr,
            "patch_target": calc_patch_tgt,
            })

        if visualize:
            qbx_tgt_tol = qbx.copy(target_association_tolerance=0.2)

            fplot = make_field_plotter_from_bbox(
                    find_bounding_box(scat_discr.mesh), h=(0.05, 0.05, 0.3),
                    extend_factor=0.3)
            fplot_tgt = PointsTarget(actx.from_numpy(fplot.points))

            places.update({
                "qbx_target_tol": qbx_tgt_tol,
                "plot_targets": fplot_tgt,
                })

        from pytential import GeometryCollection
        places = GeometryCollection(places)
        density_discr = places.get_discretization(places.auto_source.geometry)

        # {{{ system solve

        h_max = actx.to_numpy(