def test_3d_orientation(ctx_factory, what, mesh_gen_func, visualize=False):
pytest.importorskip("pytential")
logging.basicConfig(level=logging.INFO)
ctx = ctx_factory()
queue = cl.CommandQueue(ctx)
mesh = mesh_gen_func()
logger.info("%d elements" % mesh.nelements)
from meshmode.discretization import Discretization
discr = Discretization(ctx, mesh,
PolynomialWarpAndBlendGroupFactory(1))
from pytential import bind, sym
# {{{ check normals point outward
if what == "torus":
nodes = sym.nodes(mesh.ambient_dim).as_vector()
angle = sym.atan2(nodes[1], nodes[0])
center_nodes = sym.make_obj_array([
5*sym.cos(angle),
5*sym.sin(angle),
0*angle])
normal_outward_expr = (
sym.normal(mesh.ambient_dim) | (nodes-center_nodes))
else:
normal_outward_expr = (
sym.normal(mesh.ambient_dim) | sym.nodes(mesh.ambient_dim))
normal_outward_check = bind(discr, normal_outward_expr)(queue).as_scalar() > 0
assert normal_outward_check.get().all(), normal_outward_check.get()
# }}}
normals = bind(discr, sym.normal(mesh.ambient_dim).xproject(1))(queue)
if visualize:
from meshmode.discretization.visualization import make_visualizer
vis = make_visualizer(queue, discr, 1)
vis.write_vtk_file("normals.vtu", [
("normals", normals),
])
def test_tangential_onb(actx_factory):
actx = actx_factory()
from meshmode.mesh.generation import generate_torus
mesh = generate_torus(5, 2, order=3)
discr = Discretization(
actx, mesh, InterpolatoryQuadratureSimplexGroupFactory(3))
tob = sym.tangential_onb(mesh.ambient_dim)
nvecs = tob.shape[1]
# make sure tangential_onb is mutually orthogonal and normalized
orth_check = bind(discr, sym.make_obj_array([
np.dot(tob[:, i], tob[:, j]) - (1 if i == j else 0)
for i in range(nvecs) for j in range(nvecs)])
)(actx)
for orth_i in orth_check:
assert actx.to_numpy(
actx.np.all(actx.np.abs(orth_i) < 1e-13)
)
# make sure tangential_onb is orthogonal to normal
orth_check = bind(discr, sym.make_obj_array([
np.dot(tob[:, i], sym.normal(mesh.ambient_dim).as_vector())
for i in range(nvecs)])
)(actx)
for orth_i in orth_check:
assert actx.to_numpy(
actx.np.all(actx.np.abs(orth_i) < 1e-13)
)
def representation(self,
sigma,
map_potentials=None,
qbx_forced_limit=None):
if map_potentials is None:
def map_potentials(x): # pylint:disable=function-redefined
return x
def dv(knl):
return DirectionalSourceDerivative(knl, "normal_dir")
def dt(knl):
return DirectionalSourceDerivative(knl, "tangent_dir")
normal_dir = sym.normal(2).as_vector()
tangent_dir = np.array([-normal_dir[1], normal_dir[0]])
k1 = map_potentials(sym.S(dv(dv(dv(self.knl))), sigma[0],
kernel_arguments={"normal_dir": normal_dir},
qbx_forced_limit=qbx_forced_limit)) + \
3*map_potentials(sym.S(dv(dt(dt(self.knl))), sigma[0],
kernel_arguments={"normal_dir": normal_dir,
"tangent_dir": tangent_dir},
qbx_forced_limit=qbx_forced_limit))
k2 = -map_potentials(sym.S(dv(dv(self.knl)), sigma[1],
kernel_arguments={"normal_dir": normal_dir},
qbx_forced_limit=qbx_forced_limit)) + \
map_potentials(sym.S(dt(dt(self.knl)), sigma[1],
kernel_arguments={"tangent_dir": tangent_dir},
qbx_forced_limit=qbx_forced_limit))
return k1 + k2
def test_tangential_onb(ctx_factory):
cl_ctx = ctx_factory()
queue = cl.CommandQueue(cl_ctx)
from meshmode.mesh.generation import generate_torus
mesh = generate_torus(5, 2, order=3)
discr = Discretization(cl_ctx, mesh,
InterpolatoryQuadratureSimplexGroupFactory(3))
tob = sym.tangential_onb(mesh.ambient_dim)
nvecs = tob.shape[1]
# make sure tangential_onb is mutually orthogonal and normalized
orth_check = bind(
discr,
sym.make_obj_array([
np.dot(tob[:, i], tob[:, j]) - (1 if i == j else 0)
for i in range(nvecs) for j in range(nvecs)
]))(queue)
for i, orth_i in enumerate(orth_check):
assert (cl.clmath.fabs(orth_i) < 1e-13).get().all()
# make sure tangential_onb is orthogonal to normal
orth_check = bind(
discr,
sym.make_obj_array([
np.dot(tob[:, i],
sym.normal(mesh.ambient_dim).as_vector())
for i in range(nvecs)
]))(queue)
for i, orth_i in enumerate(orth_check):
assert (cl.clmath.fabs(orth_i) < 1e-13).get().all()
def test_tangential_onb(ctx_factory):
cl_ctx = ctx_factory()
queue = cl.CommandQueue(cl_ctx)
from meshmode.mesh.generation import generate_torus
mesh = generate_torus(5, 2, order=3)
discr = Discretization(
cl_ctx, mesh,
InterpolatoryQuadratureSimplexGroupFactory(3))
tob = sym.tangential_onb(mesh.ambient_dim)
nvecs = tob.shape[1]
# make sure tangential_onb is mutually orthogonal and normalized
orth_check = bind(discr, sym.make_obj_array([
np.dot(tob[:, i], tob[:, j]) - (1 if i == j else 0)
for i in range(nvecs) for j in range(nvecs)])
)(queue)
for i, orth_i in enumerate(orth_check):
assert (cl.clmath.fabs(orth_i) < 1e-13).get().all()
# make sure tangential_onb is orthogonal to normal
orth_check = bind(discr, sym.make_obj_array([
np.dot(tob[:, i], sym.normal(mesh.ambient_dim).as_vector())
for i in range(nvecs)])
)(queue)
for i, orth_i in enumerate(orth_check):
assert (cl.clmath.fabs(orth_i) < 1e-13).get().all()
def targets_from_sources(sign, dist, dim=2):
nodes = dof_array_to_numpy(
actx,
bind(places, sym.nodes(dim, dofdesc=dd))(actx).as_vector(object))
normals = dof_array_to_numpy(
actx,
bind(places, sym.normal(dim, dofdesc=dd))(actx).as_vector(object))
return actx.from_numpy(nodes + normals * sign * dist)
def get_centers_on_side(lpot_src, sign):
adim = lpot_src.density_discr.ambient_dim
dim = lpot_src.density_discr.dim
from pytential import sym, bind
with cl.CommandQueue(lpot_src.cl_context) as queue:
nodes = bind(lpot_src.density_discr, sym.nodes(adim))(queue)
normals = bind(lpot_src.density_discr, sym.normal(adim, dim=dim))(queue)
expansion_radii = lpot_src._expansion_radii("nsources").with_queue(queue)
return (nodes + normals * sign * expansion_radii).as_vector(np.object)
def targets_from_sources(sign, dist, dim=2):
nodes = actx.to_numpy(
flatten(
bind(places, sym.nodes(dim, dofdesc=dd))(actx).as_vector(),
actx)).reshape(dim, -1)
normals = actx.to_numpy(
flatten(
bind(places, sym.normal(dim, dofdesc=dd))(actx).as_vector(),
actx)).reshape(dim, -1)
return actx.from_numpy(nodes + normals * sign * dist)
def representation(self, sigma,
map_potentials=None, qbx_forced_limit=None, **kwargs):
"""
:param sigma: symbolic variable for the density.
:param map_potentials: a callable that can be used to apply
additional transformations on all the layer potentials in the
representation, e.g. to take a target derivative.
:param kwargs: additional keyword arguments passed on to the layer
potential constructor.
"""
if map_potentials is None:
def map_potentials(x): # pylint:disable=function-redefined
return x
def dv(knl):
return DirectionalSourceDerivative(knl, "normal_dir")
def dt(knl):
return DirectionalSourceDerivative(knl, "tangent_dir")
normal_dir = sym.normal(self.dim).as_vector()
tangent_dir = np.array([-normal_dir[1], normal_dir[0]])
kwargs["qbx_forced_limit"] = qbx_forced_limit
k1 = (
map_potentials(
sym.S(dv(dv(dv(self.kernel))), sigma[0],
kernel_arguments={"normal_dir": normal_dir},
**kwargs)
)
+ 3 * map_potentials(
sym.S(dv(dt(dt(self.kernel))), sigma[0],
kernel_arguments={
"normal_dir": normal_dir, "tangent_dir": tangent_dir
},
**kwargs)
)
)
k2 = (
-map_potentials(
sym.S(dv(dv(self.kernel)), sigma[1],
kernel_arguments={"normal_dir": normal_dir},
**kwargs)
)
+ map_potentials(
sym.S(dt(dt(self.kernel)), sigma[1],
kernel_arguments={"tangent_dir": tangent_dir},
**kwargs)
)
)
return k1 + k2
def _visualize_refinement(actx: PyOpenCLArrayContext,
discr,
niter,
stage_nr,
stage_name,
flags,
visualize=False):
if not visualize:
return
if stage_nr not in (1, 2):
raise ValueError("unexpected stage number")
flags = flags.get()
logger.info("for stage %s: splitting %d/%d stage-%d elements", stage_name,
np.sum(flags), discr.mesh.nelements, stage_nr)
from meshmode.discretization.visualization import make_visualizer
vis = make_visualizer(actx, discr, 3)
assert len(flags) == discr.mesh.nelements
flags = flags.astype(bool)
nodes_flags_template = discr.zeros(actx)
nodes_flags = []
for grp in discr.groups:
meg = grp.mesh_el_group
nodes_flags_grp = actx.to_numpy(nodes_flags_template[grp.index])
nodes_flags_grp[flags[meg.element_nr_base:meg.nelements +
meg.element_nr_base]] = 1
nodes_flags.append(actx.from_numpy(nodes_flags_grp))
nodes_flags = DOFArray(actx, tuple(nodes_flags))
vis_data = [
("refine_flags", nodes_flags),
]
if 0:
from pytential import sym, bind
bdry_normals = bind(discr, sym.normal(
discr.ambient_dim))(actx).as_vector(dtype=object)
vis_data.append(("bdry_normals", bdry_normals), )
vis.write_vtk_file(f"refinement-{stage_name}-{niter:03d}.vtu", vis_data)
def visualize_refinement(niter, stage_nr, stage_name, flags):
if not visualize:
return
if stage_nr == 1:
discr = lpot_source.density_discr
elif stage_nr == 2:
discr = lpot_source.stage2_density_discr
else:
raise ValueError("unexpected stage number")
flags = flags.get()
logger.info("for stage %s: splitting %d/%d stage-%d elements",
stage_name, np.sum(flags), discr.mesh.nelements, stage_nr)
from meshmode.discretization.visualization import make_visualizer
vis = make_visualizer(wrangler.queue, discr, 3)
assert len(flags) == discr.mesh.nelements
flags = flags.astype(np.bool)
nodes_flags = np.zeros(discr.nnodes)
for grp in discr.groups:
meg = grp.mesh_el_group
grp.view(nodes_flags)[flags[meg.element_nr_base:meg.nelements +
meg.element_nr_base]] = 1
nodes_flags = cl.array.to_device(wrangler.queue, nodes_flags)
vis_data = [
("refine_flags", nodes_flags),
]
if 0:
from pytential import sym, bind
bdry_normals = bind(discr, sym.normal(discr.ambient_dim))(
wrangler.queue).as_vector(dtype=object)
vis_data.append(("bdry_normals", bdry_normals), )
vis.write_vtk_file("refinement-%s-%03d.vtu" % (stage_name, niter),
vis_data)
def visualize_refinement(niter, stage_nr, stage_name, flags):
if not visualize:
return
if stage_nr == 1:
discr = lpot_source.density_discr
elif stage_nr == 2:
discr = lpot_source.stage2_density_discr
else:
raise ValueError("unexpected stage number")
flags = flags.get()
logger.info("for stage %s: splitting %d/%d stage-%d elements",
stage_name, np.sum(flags), discr.mesh.nelements, stage_nr)
from meshmode.discretization.visualization import make_visualizer
vis = make_visualizer(wrangler.queue, discr, 3)
assert len(flags) == discr.mesh.nelements
flags = flags.astype(np.bool)
nodes_flags = np.zeros(discr.nnodes)
for grp in discr.groups:
meg = grp.mesh_el_group
grp.view(nodes_flags)[
flags[meg.element_nr_base:meg.nelements+meg.element_nr_base]] = 1
nodes_flags = cl.array.to_device(wrangler.queue, nodes_flags)
vis_data = [
("refine_flags", nodes_flags),
]
if 0:
from pytential import sym, bind
bdry_normals = bind(discr, sym.normal(discr.ambient_dim))(
wrangler.queue).as_vector(dtype=object)
vis_data.append(("bdry_normals", bdry_normals),)
vis.write_vtk_file("refinement-%s-%03d.vtu" % (stage_name, niter), vis_data)
if isinstance(kernel, HelmholtzKernel):
sigma = sigma.astype(np.complex128)
bound_bdry_op = bind(qbx, op)
#mlab.figure(bgcolor=(1, 1, 1))
if 1:
fplot = FieldPlotter(bbox_center, extent=1.5*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.vts",
[
("potential", fld_in_vol)
]
)
bdry_normals = bind(density_discr, sym.normal())(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.vtu", [
("sigma", sigma),
("bdry_normals", bdry_normals),
])
def targets_from_sources(sign, dist):
from pytential import sym, bind
dim = 2
nodes = bind(lpot_source.density_discr, sym.nodes(dim))(queue)
normals = bind(lpot_source.density_discr, sym.normal(dim))(queue)
return (nodes + normals * sign * dist).as_vector(np.object)
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))
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),
])
def main(nelements):
import logging
logging.basicConfig(level=logging.INFO)
def get_obj_array(obj_array):
from pytools.obj_array import make_obj_array
return make_obj_array([
ary.get()
for ary in obj_array
])
cl_ctx = cl.create_some_context()
queue = cl.CommandQueue(cl_ctx)
from meshmode.mesh.generation import ( # noqa
make_curve_mesh, starfish, ellipse, drop)
mesh = make_curve_mesh(
lambda t: starfish(t),
np.linspace(0, 1, nelements+1),
target_order)
coarse_density_discr = Discretization(
cl_ctx, mesh,
InterpolatoryQuadratureSimplexGroupFactory(target_order))
from pytential.qbx import QBXLayerPotentialSource
target_association_tolerance = 0.05
qbx, _ = QBXLayerPotentialSource(
coarse_density_discr, fine_order=ovsmp_target_order, qbx_order=qbx_order,
fmm_order=fmm_order,
target_association_tolerance=target_association_tolerance,
).with_refinement()
density_discr = qbx.density_discr
nodes = density_discr.nodes().with_queue(queue)
# Get normal vectors for the density discretization -- used in integration with stresslet
mv_normal = bind(density_discr, sym.normal(2))(queue)
normal = mv_normal.as_vector(np.object)
# {{{ describe bvp
from sumpy.kernel import LaplaceKernel
from pytential.symbolic.stokes import StressletWrapper
from pytools.obj_array import make_obj_array
dim=2
cse = sym.cse
nvec_sym = sym.make_sym_vector("normal", dim)
sigma_sym = sym.make_sym_vector("sigma", dim)
mu_sym = sym.var("mu")
sqrt_w = sym.sqrt_jac_q_weight(2)
inv_sqrt_w_sigma = cse(sigma_sym/sqrt_w)
# -1 for interior Dirichlet
# +1 for exterior Dirichlet
loc_sign = -1
# Create stresslet object
stresslet_obj = StressletWrapper(dim=2)
# Describe boundary operator
bdry_op_sym = loc_sign * 0.5 * sigma_sym + sqrt_w * stresslet_obj.apply(inv_sqrt_w_sigma, nvec_sym, mu_sym, qbx_forced_limit='avg')
# Bind to the qbx discretization
bound_op = bind(qbx, bdry_op_sym)
# }}}
# {{{ fix rhs and solve
def fund_soln(x, y, loc):
#with direction (1,0) for point source
r = cl.clmath.sqrt((x - loc[0])**2 + (y - loc[1])**2)
scaling = 1./(4*np.pi*mu)
xcomp = (-cl.clmath.log(r) + (x - loc[0])**2/r**2) * scaling
ycomp = ((x - loc[0])*(y - loc[1])/r**2) * scaling
return [ xcomp, ycomp ]
def couette_soln(x, y, dp, h):
scaling = 1./(2*mu)
xcomp = scaling * dp * ((y+(h/2.))**2 - h * (y+(h/2.)))
ycomp = scaling * 0*y
return [xcomp, ycomp]
if soln_type == 'fundamental':
pt_loc = np.array([2.0, 0.0])
bc = fund_soln(nodes[0], nodes[1], pt_loc)
else:
dp = -10.
h = 2.5
bc = couette_soln(nodes[0], nodes[1], dp, h)
# Get rhs vector
bvp_rhs = bind(qbx, sqrt_w*sym.make_sym_vector("bc",dim))(queue, bc=bc)
from pytential.solve import gmres
gmres_result = gmres(
bound_op.scipy_op(queue, "sigma", np.float64, mu=mu, normal=normal),
bvp_rhs, tol=1e-9, progress=True,
stall_iterations=0,
hard_failure=True)
# }}}
# {{{ postprocess/visualize
sigma = gmres_result.solution
# Describe representation of solution for evaluation in domain
representation_sym = stresslet_obj.apply(inv_sqrt_w_sigma, nvec_sym, mu_sym, qbx_forced_limit=-2)
from sumpy.visualization import FieldPlotter
nsamp = 10
eval_points_1d = np.linspace(-1., 1., nsamp)
eval_points = np.zeros((2, len(eval_points_1d)**2))
eval_points[0,:] = np.tile(eval_points_1d, len(eval_points_1d))
eval_points[1,:] = np.repeat(eval_points_1d, len(eval_points_1d))
gamma_sym = sym.var("gamma")
inv_sqrt_w_gamma = cse(gamma_sym/sqrt_w)
constant_laplace_rep = sym.D(LaplaceKernel(dim=2), inv_sqrt_w_gamma, qbx_forced_limit=None)
sqrt_w_vec = bind(qbx, sqrt_w)(queue)
def general_mask(test_points):
const_density = bind((qbx, PointsTarget(test_points)), constant_laplace_rep)(queue, gamma=sqrt_w_vec).get()
return (abs(const_density) > 0.1)
def inside_domain(test_points):
mask = general_mask(test_points)
return np.array([
row[mask]
for row in test_points])
def stride_hack(arr):
from numpy.lib.stride_tricks import as_strided
return np.array(as_strided(arr, strides=(8 * len(arr[0]), 8)))
eval_points = inside_domain(eval_points)
eval_points_dev = cl.array.to_device(queue, eval_points)
# Evaluate the solution at the evaluation points
vel = bind(
(qbx, PointsTarget(eval_points_dev)),
representation_sym)(queue, sigma=sigma, mu=mu, normal=normal)
print("@@@@@@@@")
vel = get_obj_array(vel)
if soln_type == 'fundamental':
exact_soln = fund_soln(eval_points_dev[0], eval_points_dev[1], pt_loc)
else:
exact_soln = couette_soln(eval_points_dev[0], eval_points_dev[1], dp, h)
err = vel - get_obj_array(exact_soln)
print("@@@@@@@@")
print("L2 error estimate: ", np.sqrt((2./(nsamp-1))**2*np.sum(err[0]*err[0]) + (2./(nsamp-1))**2*np.sum(err[1]*err[1])))
max_error_loc = [abs(err[0]).argmax(), abs(err[1]).argmax()]
print("max error at sampled points: ", max(abs(err[0])), max(abs(err[1])))
print("exact velocity at max error points: x -> ", err[0][max_error_loc[0]], ", y -> ", err[1][max_error_loc[1]])
from pytential.symbolic.mappers import DerivativeTaker
rep_pressure = stresslet_obj.apply_pressure(inv_sqrt_w_sigma, nvec_sym, mu_sym, qbx_forced_limit=-2)
pressure = bind((qbx, PointsTarget(eval_points_dev)),
rep_pressure)(queue, sigma=sigma, mu=mu, normal=normal)
pressure = pressure.get()
print "pressure = ", pressure
x_dir_vecs = np.zeros((2,len(eval_points[0])))
x_dir_vecs[0,:] = 1.0
y_dir_vecs = np.zeros((2, len(eval_points[0])))
y_dir_vecs[1,:] = 1.0
x_dir_vecs = cl.array.to_device(queue, x_dir_vecs)
y_dir_vecs = cl.array.to_device(queue, y_dir_vecs)
dir_vec_sym = sym.make_sym_vector("force_direction", dim)
rep_stress = stresslet_obj.apply_stress(inv_sqrt_w_sigma, nvec_sym, dir_vec_sym, mu_sym, qbx_forced_limit=-2)
applied_stress_x = bind((qbx, PointsTarget(eval_points_dev)),
rep_stress)(queue, sigma=sigma, normal=normal, force_direction=x_dir_vecs, mu=mu)
applied_stress_x = get_obj_array(applied_stress_x)
applied_stress_y = bind((qbx, PointsTarget(eval_points_dev)),
rep_stress)(queue, sigma=sigma, normal=normal, force_direction=y_dir_vecs, mu=mu)
applied_stress_y = get_obj_array(applied_stress_y)
print "stress applied to x direction: ", applied_stress_x
print "stress applied to y direction: ", applied_stress_y
import matplotlib.pyplot as plt
plt.quiver(eval_points[0], eval_points[1], vel[0], vel[1], linewidth=0.1)
file_name = "field-n%s.pdf"%(nelements)
plt.savefig(file_name)
return (max(abs(err[0])), max(abs(err[1])))
def operator(self, unknown):
result = np.zeros(4 * len(self.interfaces), dtype=object)
unk_idx = self.unknown_index
for i in range(len(self.interfaces)):
idx_jt = unk_idx["jz", i]
idx_jz = unk_idx["jt", i]
idx_mt = unk_idx["mz", i]
idx_mz = unk_idx["mt", i]
phi1 = unknown[idx_jt]
phi2 = unknown[idx_jz]
phi3 = unknown[idx_mt]
phi4 = unknown[idx_mz]
ne = self.ne
dom0i, dom1i, where = self.interfaces[i]
tangent = self.tangent(where)
normal = sym.cse(sym.normal(2, 1, where), "normal")
S = self.S # noqa
D = self.D # noqa
T = self.T # noqa
def Tt(where, dom, density): # noqa
return sym.tangential_derivative(2, T(where, dom,
density)).xproject(0)
def Sn(dom, density): # noqa
return sym.normal_derivative(
2, S(dom, density, qbx_forced_limit="avg"))
def St(dom, density): # noqa
return sym.tangential_derivative(2, S(dom,
density)).xproject(0)
n0 = self.domain_n_exprs[dom0i]
n1 = self.domain_n_exprs[dom1i]
a11 = sym.cse(n0**2 * D(dom0i, phi1) - n1**2 * D(dom1i, phi1),
"a11")
a22 = sym.cse(-n0**2 * Sn(dom0i, phi2) + n1**2 * Sn(dom1i, phi2),
"a22")
a33 = sym.cse(D(dom0i, phi3) - D(dom1i, phi3), "a33")
a44 = sym.cse(-Sn(dom0i, phi4) + Sn(dom1i, phi4), "a44")
a21 = sym.cse(
-1j * ne *
(n0**2 * tangent.scalar_product(S(dom0i, normal * phi1)) -
n1**2 * tangent.scalar_product(S(dom1i, normal * phi1))),
"a21")
a43 = sym.cse(
-1j * ne * (tangent.scalar_product(S(dom0i, normal * phi3)) -
tangent.scalar_product(S(dom1i, normal * phi3))),
"a43")
a13 = +1 * sym.cse(
ne * (T(where, dom0i, phi3) - T(where, dom1i, phi3)), "a13")
a31 = -1 * sym.cse(
ne * (T(where, dom0i, phi1) - T(where, dom1i, phi1)), "a31")
a24 = +1 * sym.cse(ne * (St(dom0i, phi4) - St(dom1i, phi4)), "a24")
a42 = -1 * sym.cse(ne * (St(dom0i, phi2) - St(dom1i, phi2)), "a42")
a14 = sym.cse(
1j * ((n0**2 - ne**2) * S(dom0i, phi4) -
(n1**2 - ne**2) * S(dom1i, phi4)), "a14")
a32 = -sym.cse(
1j * ((n0**2 - ne**2) * S(dom0i, phi2) -
(n1**2 - ne**2) * S(dom1i, phi2)), "a32")
def a23_expr(phi):
return (
1j * (Tt(where, dom0i, phi) - Tt(where, dom1i, phi)) - 1j *
(n0**2 * tangent.scalar_product(S(dom0i, tangent * phi)) -
n1**2 * tangent.scalar_product(S(dom1i, tangent * phi))))
a23 = +1 * sym.cse(a23_expr(phi3), "a23")
a41 = -1 * sym.cse(a23_expr(phi1), "a41")
d1 = (n0**2 + n1**2) / 2 * phi1
d2 = (n0**2 + n1**2) / 2 * phi2
d3 = phi3
d4 = phi4
result[idx_jt] += d1 + a11 + 000 + a13 + a14
result[idx_jz] += d2 + a21 + a22 + a23 + a24
result[idx_mt] += d3 + a31 + a32 + a33 + 0
result[idx_mz] += d4 + a41 + a42 + a43 + a44
# TODO: L2 weighting
# TODO: Add representation contributions to other boundaries
# abutting the domain
return result
def test_sanity_single_element(ctx_getter, dim, order, visualize=False):
pytest.importorskip("pytential")
cl_ctx = ctx_getter()
queue = cl.CommandQueue(cl_ctx)
from modepy.tools import unit_vertices
vertices = unit_vertices(dim).T.copy()
center = np.empty(dim, np.float64)
center.fill(-0.5)
import modepy as mp
from meshmode.mesh import SimplexElementGroup, Mesh, BTAG_ALL
mg = SimplexElementGroup(
order=order,
vertex_indices=np.arange(dim + 1, dtype=np.int32).reshape(1, -1),
nodes=mp.warp_and_blend_nodes(dim, order).reshape(dim, 1, -1),
dim=dim)
mesh = Mesh(vertices, [mg],
nodal_adjacency=None,
facial_adjacency_groups=None)
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
PolynomialWarpAndBlendGroupFactory
vol_discr = Discretization(cl_ctx, mesh,
PolynomialWarpAndBlendGroupFactory(order + 3))
# {{{ volume calculation check
vol_x = vol_discr.nodes().with_queue(queue)
vol_one = vol_x[0].copy()
vol_one.fill(1)
from pytential import norm, integral # noqa
from pytools import factorial
true_vol = 1 / factorial(dim) * 2**dim
comp_vol = integral(vol_discr, queue, vol_one)
rel_vol_err = abs(true_vol - comp_vol) / true_vol
assert rel_vol_err < 1e-12
# }}}
# {{{ boundary discretization
from meshmode.discretization.connection import make_face_restriction
bdry_connection = make_face_restriction(
vol_discr, PolynomialWarpAndBlendGroupFactory(order + 3), BTAG_ALL)
bdry_discr = bdry_connection.to_discr
# }}}
# {{{ visualizers
from meshmode.discretization.visualization import make_visualizer
#vol_vis = make_visualizer(queue, vol_discr, 4)
bdry_vis = make_visualizer(queue, bdry_discr, 4)
# }}}
from pytential import bind, sym
bdry_normals = bind(bdry_discr,
sym.normal(dim))(queue).as_vector(dtype=object)
if visualize:
bdry_vis.write_vtk_file("boundary.vtu",
[("bdry_normals", bdry_normals)])
from pytential import bind, sym
normal_outward_check = bind(
bdry_discr,
sym.normal(dim)
| (sym.nodes(dim) + 0.5 * sym.ones_vec(dim)),
)(queue).as_scalar() > 0
assert normal_outward_check.get().all(), normal_outward_check.get()
def test_sanity_single_element(actx_factory,
dim,
mesh_order,
group_cls,
visualize=False):
pytest.importorskip("pytential")
actx = actx_factory()
if group_cls is SimplexElementGroup:
group_factory = PolynomialWarpAndBlendGroupFactory(mesh_order + 3)
elif group_cls is TensorProductElementGroup:
group_factory = LegendreGaussLobattoTensorProductGroupFactory(
mesh_order + 3)
else:
raise TypeError
import modepy as mp
shape = group_cls._modepy_shape_cls(dim)
space = mp.space_for_shape(shape, mesh_order)
vertices = mp.unit_vertices_for_shape(shape)
nodes = mp.edge_clustered_nodes_for_space(space, shape).reshape(dim, 1, -1)
vertex_indices = np.arange(shape.nvertices, dtype=np.int32).reshape(1, -1)
center = np.empty(dim, np.float64)
center.fill(-0.5)
mg = group_cls(mesh_order, vertex_indices, nodes, dim=dim)
mesh = Mesh(vertices, [mg], is_conforming=True)
from meshmode.discretization import Discretization
vol_discr = Discretization(actx, mesh, group_factory)
# {{{ volume calculation check
if isinstance(mg, SimplexElementGroup):
from pytools import factorial
true_vol = 1 / factorial(dim) * 2**dim
elif isinstance(mg, TensorProductElementGroup):
true_vol = 2**dim
else:
raise TypeError
nodes = thaw(vol_discr.nodes(), actx)
vol_one = 1 + 0 * nodes[0]
from pytential import norm, integral # noqa
comp_vol = integral(vol_discr, vol_one)
rel_vol_err = abs(true_vol - comp_vol) / true_vol
assert rel_vol_err < 1e-12
# }}}
# {{{ boundary discretization
from meshmode.discretization.connection import make_face_restriction
bdry_connection = make_face_restriction(actx, vol_discr, group_factory,
BTAG_ALL)
bdry_discr = bdry_connection.to_discr
# }}}
from pytential import bind, sym
bdry_normals = bind(bdry_discr, sym.normal(dim).as_vector())(actx)
if visualize:
from meshmode.discretization.visualization import make_visualizer
bdry_vis = make_visualizer(actx, bdry_discr, 4)
bdry_vis.write_vtk_file("sanity_single_element_boundary.vtu",
[("normals", bdry_normals)])
normal_outward_check = bind(
bdry_discr,
sym.normal(dim)
| (sym.nodes(dim) + 0.5 * sym.ones_vec(dim)),
)(actx).as_scalar()
normal_outward_check = flatten_to_numpy(actx, normal_outward_check > 0)
assert normal_outward_check.all(), normal_outward_check
def test_3d_jump_relations(ctx_factory, relation, visualize=False):
# logging.basicConfig(level=logging.INFO)
cl_ctx = ctx_factory()
queue = cl.CommandQueue(cl_ctx)
actx = PyOpenCLArrayContext(queue)
if relation == "div_s":
target_order = 3
else:
target_order = 4
qbx_order = target_order
from pytools.convergence import EOCRecorder
eoc_rec = EOCRecorder()
for nel_factor in [6, 10, 14]:
from meshmode.mesh.generation import generate_torus
mesh = generate_torus(
5, 2, order=target_order,
n_major=2*nel_factor, n_minor=nel_factor)
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
InterpolatoryQuadratureSimplexGroupFactory
pre_discr = Discretization(
actx, mesh,
InterpolatoryQuadratureSimplexGroupFactory(3))
from pytential.qbx import QBXLayerPotentialSource
qbx = QBXLayerPotentialSource(
pre_discr, fine_order=4*target_order,
qbx_order=qbx_order,
fmm_order=qbx_order + 5,
fmm_backend="fmmlib"
)
places = GeometryCollection(qbx)
density_discr = places.get_discretization(places.auto_source.geometry)
from sumpy.kernel import LaplaceKernel
knl = LaplaceKernel(3)
def nxcurlS(qbx_forced_limit):
return sym.n_cross(sym.curl(sym.S(
knl,
sym.cse(sym.tangential_to_xyz(density_sym), "jxyz"),
qbx_forced_limit=qbx_forced_limit)))
from meshmode.dof_array import thaw
x, y, z = thaw(actx, density_discr.nodes())
m = actx.np
if relation == "nxcurls":
density_sym = sym.make_sym_vector("density", 2)
jump_identity_sym = (
nxcurlS(+1)
- (nxcurlS("avg") + 0.5*sym.tangential_to_xyz(density_sym)))
# The tangential coordinate system is element-local, so we can't just
# conjure up some globally smooth functions, interpret their values
# in the tangential coordinate system, and be done. Instead, generate
# an XYZ function and project it.
density = bind(places,
sym.xyz_to_tangential(sym.make_sym_vector("jxyz", 3)))(
actx,
jxyz=sym.make_obj_array([
m.cos(0.5*x) * m.cos(0.5*y) * m.cos(0.5*z),
m.sin(0.5*x) * m.cos(0.5*y) * m.sin(0.5*z),
m.sin(0.5*x) * m.cos(0.5*y) * m.cos(0.5*z),
]))
elif relation == "sp":
density = m.cos(2*x) * m.cos(2*y) * m.cos(z)
density_sym = sym.var("density")
jump_identity_sym = (
sym.Sp(knl, density_sym, qbx_forced_limit=+1)
- (sym.Sp(knl, density_sym, qbx_forced_limit="avg")
- 0.5*density_sym))
elif relation == "div_s":
density = m.cos(2*x) * m.cos(2*y) * m.cos(z)
density_sym = sym.var("density")
jump_identity_sym = (
sym.div(sym.S(knl, sym.normal(3).as_vector()*density_sym,
qbx_forced_limit="avg"))
+ sym.D(knl, density_sym, qbx_forced_limit="avg"))
else:
raise ValueError("unexpected value of 'relation': %s" % relation)
bound_jump_identity = bind(places, jump_identity_sym)
jump_identity = bound_jump_identity(actx, density=density)
h_max = bind(places, sym.h_max(qbx.ambient_dim))(actx)
err = (
norm(density_discr, jump_identity, np.inf)
/ norm(density_discr, density, np.inf))
print("ERROR", h_max, err)
eoc_rec.add_data_point(h_max, err)
# {{{ visualization
if visualize and relation == "nxcurls":
nxcurlS_ext = bind(places, nxcurlS(+1))(actx, density=density)
nxcurlS_avg = bind(places, nxcurlS("avg"))(actx, density=density)
jtxyz = bind(places, sym.tangential_to_xyz(density_sym))(
actx, density=density)
from meshmode.discretization.visualization import make_visualizer
bdry_vis = make_visualizer(actx, qbx.density_discr, target_order+3)
bdry_normals = bind(places, sym.normal(3))(actx)\
.as_vector(dtype=object)
bdry_vis.write_vtk_file("source-%s.vtu" % nel_factor, [
("jt", jtxyz),
("nxcurlS_ext", nxcurlS_ext),
("nxcurlS_avg", nxcurlS_avg),
("bdry_normals", bdry_normals),
])
if visualize and relation == "sp":
op = sym.Sp(knl, density_sym, qbx_forced_limit=+1)
sp_ext = bind(places, op)(actx, density=density)
op = sym.Sp(knl, density_sym, qbx_forced_limit="avg")
sp_avg = bind(places, op)(actx, density=density)
from meshmode.discretization.visualization import make_visualizer
bdry_vis = make_visualizer(actx, qbx.density_discr, target_order+3)
bdry_normals = bind(places,
sym.normal(3))(actx).as_vector(dtype=object)
bdry_vis.write_vtk_file("source-%s.vtu" % nel_factor, [
("density", density),
("sp_ext", sp_ext),
("sp_avg", sp_avg),
("bdry_normals", bdry_normals),
])
# }}}
print(eoc_rec)
assert eoc_rec.order_estimate() >= qbx_order - 1.5
def test_sanity_balls(ctx_getter, src_file, dim, mesh_order,
visualize=False):
pytest.importorskip("pytential")
logging.basicConfig(level=logging.INFO)
ctx = ctx_getter()
queue = cl.CommandQueue(ctx)
from pytools.convergence import EOCRecorder
vol_eoc_rec = EOCRecorder()
surf_eoc_rec = EOCRecorder()
# overkill
quad_order = mesh_order
from pytential import bind, sym
for h in [0.2, 0.14, 0.1]:
from meshmode.mesh.io import generate_gmsh, FileSource
mesh = generate_gmsh(
FileSource(src_file), dim, order=mesh_order,
other_options=["-string", "Mesh.CharacteristicLengthMax = %g;" % h],
force_ambient_dim=dim)
logger.info("%d elements" % mesh.nelements)
# {{{ discretizations and connections
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
InterpolatoryQuadratureSimplexGroupFactory
vol_discr = Discretization(ctx, mesh,
InterpolatoryQuadratureSimplexGroupFactory(quad_order))
from meshmode.discretization.connection import make_boundary_restriction
bdry_mesh, bdry_discr, bdry_connection = make_boundary_restriction(
queue, vol_discr,
InterpolatoryQuadratureSimplexGroupFactory(quad_order))
# }}}
# {{{ visualizers
from meshmode.discretization.visualization import make_visualizer
vol_vis = make_visualizer(queue, vol_discr, 20)
bdry_vis = make_visualizer(queue, bdry_discr, 20)
# }}}
from math import gamma
true_surf = 2*np.pi**(dim/2)/gamma(dim/2)
true_vol = true_surf/dim
vol_x = vol_discr.nodes().with_queue(queue)
vol_one = vol_x[0].copy()
vol_one.fill(1)
from pytential import norm, integral # noqa
comp_vol = integral(vol_discr, queue, vol_one)
rel_vol_err = abs(true_vol - comp_vol) / true_vol
vol_eoc_rec.add_data_point(h, rel_vol_err)
print("VOL", true_vol, comp_vol)
bdry_x = bdry_discr.nodes().with_queue(queue)
bdry_one_exact = bdry_x[0].copy()
bdry_one_exact.fill(1)
bdry_one = bdry_connection(queue, vol_one).with_queue(queue)
intp_err = norm(bdry_discr, queue, bdry_one-bdry_one_exact)
assert intp_err < 1e-14
comp_surf = integral(bdry_discr, queue, bdry_one)
rel_surf_err = abs(true_surf - comp_surf) / true_surf
surf_eoc_rec.add_data_point(h, rel_surf_err)
print("SURF", true_surf, comp_surf)
if visualize:
vol_vis.write_vtk_file("volume-h=%g.vtu" % h, [
("f", vol_one),
("area_el", bind(vol_discr, sym.area_element())(queue)),
])
bdry_vis.write_vtk_file("boundary-h=%g.vtu" % h, [("f", bdry_one)])
# {{{ check normals point outward
normal_outward_check = bind(bdry_discr,
sym.normal() | sym.Nodes(),
)(queue).as_scalar() > 0
assert normal_outward_check.get().all(), normal_outward_check.get()
# }}}
print("---------------------------------")
print("VOLUME")
print("---------------------------------")
print(vol_eoc_rec)
assert vol_eoc_rec.order_estimate() >= mesh_order
print("---------------------------------")
print("SURFACE")
print("---------------------------------")
print(surf_eoc_rec)
assert surf_eoc_rec.order_estimate() >= mesh_order
def center_info(self):
"""Return a :class:`CenterInfo`. |cached|
"""
self_discr = self.lpot_source.density_discr
ncenters = 0
for el_group in self_discr.groups:
kept_indices = self.kept_center_indices(el_group)
# two: one for positive side, one for negative side
ncenters += 2 * len(kept_indices) * el_group.nelements
from pytential import sym, bind
from pytools.obj_array import make_obj_array
with cl.CommandQueue(self.cl_context) as queue:
radii_sym = sym.cse(2*sym.area_element(), "radii")
all_radii, all_pos_centers, all_neg_centers = bind(self_discr,
make_obj_array([
radii_sym,
sym.Nodes() + radii_sym*sym.normal(),
sym.Nodes() - radii_sym*sym.normal()
]))(queue)
# The centers are returned from the above as multivectors.
all_pos_centers = all_pos_centers.as_vector(np.object)
all_neg_centers = all_neg_centers.as_vector(np.object)
# -1 for inside, +1 for outside
sides = cl.array.empty(
self.cl_context, ncenters, np.int8)
radii = cl.array.empty(
self.cl_context, ncenters, self.coord_dtype)
centers = make_obj_array([
cl.array.empty(self.cl_context, ncenters,
self.coord_dtype)
for i in range(self_discr.ambient_dim)])
ibase = 0
for el_group in self_discr.groups:
kept_center_indices = self.kept_center_indices(el_group)
group_len = len(kept_indices) * el_group.nelements
for side, all_centers in [
(+1, all_pos_centers),
(-1, all_neg_centers),
]:
sides[ibase:ibase + group_len].fill(side, queue=queue)
radii_view = radii[ibase:ibase + group_len] \
.reshape(el_group.nelements, len(kept_indices))
centers_view = make_obj_array([
centers_i[ibase:ibase + group_len]
.reshape((el_group.nelements, len(kept_indices)))
for centers_i in centers
])
all_centers_view = make_obj_array([
el_group.view(pos_centers_i)
for pos_centers_i in all_centers
])
self.code_getter.pick_expansion_centers(queue,
centers=centers_view,
all_centers=all_centers_view,
radii=radii_view,
all_radii=el_group.view(all_radii),
kept_center_indices=kept_center_indices)
ibase += group_len
assert ibase == ncenters
return CenterInfo(
sides=sides,
radii=radii,
centers=centers).with_queue(None)
4 * target_order,
case.qbx_order,
fmm_order=case.fmm_order,
fmm_backend=case.fmm_backend,
_expansions_in_tree_have_extent=True,
_expansion_stick_out_factor=getattr(case,
"_expansion_stick_out_factor",
0),
).with_refinement(**refiner_extra_kwargs)
density_discr = qbx.density_discr
# {{{ compute values of a solution to the PDE
nodes_host = density_discr.nodes().get(queue)
normal = bind(density_discr, sym.normal(d))(queue).as_vector(np.object)
normal_host = [normal[j].get() for j in range(d)]
if k != 0:
if d == 2:
angle = 0.3
wave_vec = np.array([np.cos(angle), np.sin(angle)])
u = np.exp(1j * k * np.tensordot(wave_vec, nodes_host, axes=1))
grad_u = 1j * k * wave_vec[:, np.newaxis] * u
elif d == 3:
center = np.array([3, 1, 2])
diff = nodes_host - center[:, np.newaxis]
r = la.norm(diff, axis=0)
u = np.exp(1j * k * r) / r
grad_u = diff * (1j * k * u / r - u / r**2)
else:
def get_green_error(geometry_getter,
lpot_kwargs,
center,
k,
vis_error_filename=None,
vis_order=TARGET_ORDER):
"""Return the Green identity error for a geometry.
The density function for the Green error is the on-surface restriction of
the potential due to a source charge in the exterior of the geometry, whose
location is specified. The error is reported relative to the norm of the
density.
Params:
geometry_getter: Geometry getter
lpot_kwargs: Constructor args to QBXLayerPotentialSource
center: Center of source charge used to obtain the constructed density
k: Helmholtz parameter
Returns:
A dictionary containing Green identity errors in l^2 and l^infty norm
"""
context = cl.create_some_context(interactive=False)
queue = cl.CommandQueue(context)
lpot_source = geometry_getter(queue, lpot_kwargs)
d = lpot_source.ambient_dim
u_sym = sym.var("u")
dn_u_sym = sym.var("dn_u")
from sumpy.kernel import LaplaceKernel, HelmholtzKernel
lap_k_sym = LaplaceKernel(d)
if k == 0:
k_sym = lap_k_sym
knl_kwargs = {}
else:
k_sym = HelmholtzKernel(d)
knl_kwargs = {"k": sym.var("k")}
S_part = (sym.S(k_sym, dn_u_sym, qbx_forced_limit=-1, **knl_kwargs))
D_part = (sym.D(k_sym, u_sym, qbx_forced_limit="avg", **knl_kwargs))
sym_op = S_part - D_part - 0.5 * u_sym
density_discr = lpot_source.density_discr
# {{{ compute values of a solution to the PDE
nodes_host = density_discr.nodes().get(queue)
normal = bind(density_discr, sym.normal(d))(queue).as_vector(np.object)
normal_host = [normal[j].get() for j in range(d)]
if k != 0:
if d == 2:
angle = 0.3
wave_vec = np.array([np.cos(angle), np.sin(angle)])
u = np.exp(1j * k * np.tensordot(wave_vec, nodes_host, axes=1))
grad_u = 1j * k * wave_vec[:, np.newaxis] * u
else:
diff = nodes_host - center[:, np.newaxis]
r = la.norm(diff, axis=0)
u = np.exp(1j * k * r) / r
grad_u = diff * (1j * k * u / r - u / r**2)
else:
diff = nodes_host - center[:, np.newaxis]
dist_squared = np.sum(diff**2, axis=0)
dist = np.sqrt(dist_squared)
if d == 2:
u = np.log(dist)
grad_u = diff / dist_squared
elif d == 3:
u = 1 / dist
grad_u = -diff / dist**3
else:
assert False
dn_u = 0
for i in range(d):
dn_u = dn_u + normal_host[i] * grad_u[i]
# }}}
u_dev = cl.array.to_device(queue, u)
dn_u_dev = cl.array.to_device(queue, dn_u)
grad_u_dev = cl.array.to_device(queue, grad_u)
bound_op = bind(lpot_source, sym_op)
error = bound_op(queue, u=u_dev, dn_u=dn_u_dev, grad_u=grad_u_dev, k=k)
scaling_l2 = 1 / norm(density_discr, queue, u_dev, p=2)
scaling_linf = 1 / norm(density_discr, queue, u_dev, p="inf")
if vis_error_filename is not None:
from meshmode.discretization.visualization import make_visualizer
bdry_vis = make_visualizer(queue, lpot_source.density_discr, vis_order)
bdry_vis.write_vtk_file(vis_error_filename, [
("green_zero", error),
("u_dev", u_dev),
])
err_l2 = scaling_l2 * norm(density_discr, queue, error, p=2)
err_linf = scaling_linf * norm(density_discr, queue, error, p="inf")
return dict(err_l2=err_l2, err_linf=err_linf)
def operator(self, unknown):
result = np.zeros(4*len(self.interfaces), dtype=object)
unk_idx = self.unknown_index
for i in range(len(self.interfaces)):
idx_jt = unk_idx["jz", i]
idx_jz = unk_idx["jt", i]
idx_mt = unk_idx["mz", i]
idx_mz = unk_idx["mt", i]
phi1 = unknown[idx_jt]
phi2 = unknown[idx_jz]
phi3 = unknown[idx_mt]
phi4 = unknown[idx_mz]
ne = self.ne
dom0i, dom1i, where = self.interfaces[i]
tangent = self.tangent(where)
normal = sym.cse(
sym.normal(2, 1, where),
"normal")
S = self.S # noqa
D = self.D # noqa
T = self.T # noqa
def Tt(where, dom, density): # noqa
return sym.tangential_derivative(
2, T(where, dom, density)).xproject(0)
def Sn(dom, density): # noqa
return sym.normal_derivative(
2,
S(dom, density,
qbx_forced_limit="avg"))
def St(dom, density): # noqa
return sym.tangential_derivative(2, S(dom, density)).xproject(0)
n0 = self.domain_n_exprs[dom0i]
n1 = self.domain_n_exprs[dom1i]
a11 = sym.cse(n0**2 * D(dom0i, phi1) - n1**2 * D(dom1i, phi1), "a11")
a22 = sym.cse(-n0**2 * Sn(dom0i, phi2) + n1**2 * Sn(dom1i, phi2), "a22")
a33 = sym.cse(D(dom0i, phi3)-D(dom1i, phi3), "a33")
a44 = sym.cse(-Sn(dom0i, phi4) + Sn(dom1i, phi4), "a44")
a21 = sym.cse(-1j * ne * (
n0**2 * tangent.scalar_product(
S(dom0i, normal * phi1))
- n1**2 * tangent.scalar_product(
S(dom1i, normal * phi1))), "a21")
a43 = sym.cse(-1j * ne * (
tangent.scalar_product(
S(dom0i, normal * phi3))
- tangent.scalar_product(
S(dom1i, normal * phi3))), "a43")
a13 = +1*sym.cse(
ne*(T(where, dom0i, phi3) - T(where, dom1i, phi3)), "a13")
a31 = -1*sym.cse(
ne*(T(where, dom0i, phi1) - T(where, dom1i, phi1)), "a31")
a24 = +1*sym.cse(ne*(St(dom0i, phi4) - St(dom1i, phi4)), "a24")
a42 = -1*sym.cse(ne*(St(dom0i, phi2) - St(dom1i, phi2)), "a42")
a14 = sym.cse(1j*(
(n0**2 - ne**2) * S(dom0i, phi4)
- (n1**2 - ne**2) * S(dom1i, phi4)
), "a14")
a32 = -sym.cse(1j*(
(n0**2 - ne**2) * S(dom0i, phi2)
- (n1**2 - ne**2) * S(dom1i, phi2)
), "a32")
def a23_expr(phi):
return (
1j * (Tt(where, dom0i, phi) - Tt(where, dom1i, phi))
- 1j * (
n0**2 * tangent.scalar_product(
S(dom0i, tangent * phi))
- n1**2 * tangent.scalar_product(
S(dom1i, tangent * phi))))
a23 = +1*sym.cse(a23_expr(phi3), "a23")
a41 = -1*sym.cse(a23_expr(phi1), "a41")
d1 = (n0**2 + n1**2)/2 * phi1
d2 = (n0**2 + n1**2)/2 * phi2
d3 = phi3
d4 = phi4
result[idx_jt] += d1 + a11 + 000 + a13 + a14
result[idx_jz] += d2 + a21 + a22 + a23 + a24
result[idx_mt] += d3 + a31 + a32 + a33 + 0
result[idx_mz] += d4 + a41 + a42 + a43 + a44
# TODO: L2 weighting
# TODO: Add representation contributions to other boundaries
# abutting the domain
return result
def run_exterior_stokes_2d(ctx_factory,
nelements,
mesh_order=4,
target_order=4,
qbx_order=4,
fmm_order=10,
mu=1,
circle_rad=1.5,
do_plot=False):
# This program tests an exterior Stokes flow in 2D using the
# compound representation given in Hsiao & Kress,
# ``On an integral equation for the two-dimensional exterior Stokes problem,''
# Applied Numerical Mathematics 1 (1985).
logging.basicConfig(level=logging.INFO)
cl_ctx = cl.create_some_context()
queue = cl.CommandQueue(cl_ctx)
ovsmp_target_order = 4 * target_order
from meshmode.mesh.generation import ( # noqa
make_curve_mesh, starfish, ellipse, drop)
mesh = make_curve_mesh(lambda t: circle_rad * ellipse(1, t),
np.linspace(0, 1, nelements + 1), target_order)
coarse_density_discr = Discretization(
cl_ctx, mesh, InterpolatoryQuadratureSimplexGroupFactory(target_order))
from pytential.qbx import QBXLayerPotentialSource
target_association_tolerance = 0.05
qbx, _ = QBXLayerPotentialSource(
coarse_density_discr,
fine_order=ovsmp_target_order,
qbx_order=qbx_order,
fmm_order=fmm_order,
target_association_tolerance=target_association_tolerance,
_expansions_in_tree_have_extent=True,
).with_refinement()
density_discr = qbx.density_discr
normal = bind(density_discr, sym.normal(2).as_vector())(queue)
path_length = bind(density_discr, sym.integral(2, 1, 1))(queue)
# {{{ describe bvp
from pytential.symbolic.stokes import StressletWrapper, StokesletWrapper
dim = 2
cse = sym.cse
sigma_sym = sym.make_sym_vector("sigma", dim)
meanless_sigma_sym = cse(sigma_sym - sym.mean(2, 1, sigma_sym))
int_sigma = sym.Ones() * sym.integral(2, 1, sigma_sym)
nvec_sym = sym.make_sym_vector("normal", dim)
mu_sym = sym.var("mu")
# -1 for interior Dirichlet
# +1 for exterior Dirichlet
loc_sign = 1
stresslet_obj = StressletWrapper(dim=2)
stokeslet_obj = StokesletWrapper(dim=2)
bdry_op_sym = (-loc_sign * 0.5 * sigma_sym - stresslet_obj.apply(
sigma_sym, nvec_sym, mu_sym, qbx_forced_limit='avg') +
stokeslet_obj.apply(
meanless_sigma_sym, mu_sym, qbx_forced_limit='avg') -
(0.5 / np.pi) * int_sigma)
# }}}
bound_op = bind(qbx, bdry_op_sym)
# {{{ fix rhs and solve
def fund_soln(x, y, loc, strength):
#with direction (1,0) for point source
r = cl.clmath.sqrt((x - loc[0])**2 + (y - loc[1])**2)
scaling = strength / (4 * np.pi * mu)
xcomp = (-cl.clmath.log(r) + (x - loc[0])**2 / r**2) * scaling
ycomp = ((x - loc[0]) * (y - loc[1]) / r**2) * scaling
return [xcomp, ycomp]
def rotlet_soln(x, y, loc):
r = cl.clmath.sqrt((x - loc[0])**2 + (y - loc[1])**2)
xcomp = -(y - loc[1]) / r**2
ycomp = (x - loc[0]) / r**2
return [xcomp, ycomp]
def fund_and_rot_soln(x, y, loc, strength):
#with direction (1,0) for point source
r = cl.clmath.sqrt((x - loc[0])**2 + (y - loc[1])**2)
scaling = strength / (4 * np.pi * mu)
xcomp = ((-cl.clmath.log(r) + (x - loc[0])**2 / r**2) * scaling -
(y - loc[1]) * strength * 0.125 / r**2 + 3.3)
ycomp = (((x - loc[0]) * (y - loc[1]) / r**2) * scaling +
(x - loc[0]) * strength * 0.125 / r**2 + 1.5)
return [xcomp, ycomp]
nodes = density_discr.nodes().with_queue(queue)
fund_soln_loc = np.array([0.5, -0.2])
strength = 100.
bc = fund_and_rot_soln(nodes[0], nodes[1], fund_soln_loc, strength)
omega_sym = sym.make_sym_vector("omega", dim)
u_A_sym_bdry = stokeslet_obj.apply( # noqa: N806
omega_sym, mu_sym, qbx_forced_limit=1)
omega = [
cl.array.to_device(queue,
(strength / path_length) * np.ones(len(nodes[0]))),
cl.array.to_device(queue, np.zeros(len(nodes[0])))
]
bvp_rhs = bind(qbx,
sym.make_sym_vector("bc", dim) + u_A_sym_bdry)(queue,
bc=bc,
mu=mu,
omega=omega)
gmres_result = gmres(bound_op.scipy_op(queue,
"sigma",
np.float64,
mu=mu,
normal=normal),
bvp_rhs,
x0=bvp_rhs,
tol=1e-9,
progress=True,
stall_iterations=0,
hard_failure=True)
# }}}
# {{{ postprocess/visualize
sigma = gmres_result.solution
sigma_int_val_sym = sym.make_sym_vector("sigma_int_val", 2)
int_val = bind(qbx, sym.integral(2, 1, sigma_sym))(queue, sigma=sigma)
int_val = -int_val / (2 * np.pi)
print("int_val = ", int_val)
u_A_sym_vol = stokeslet_obj.apply( # noqa: N806
omega_sym, mu_sym, qbx_forced_limit=2)
representation_sym = (
-stresslet_obj.apply(sigma_sym, nvec_sym, mu_sym, qbx_forced_limit=2) +
stokeslet_obj.apply(meanless_sigma_sym, mu_sym, qbx_forced_limit=2) -
u_A_sym_vol + sigma_int_val_sym)
nsamp = 30
eval_points_1d = np.linspace(-3., 3., nsamp)
eval_points = np.zeros((2, len(eval_points_1d)**2))
eval_points[0, :] = np.tile(eval_points_1d, len(eval_points_1d))
eval_points[1, :] = np.repeat(eval_points_1d, len(eval_points_1d))
def circle_mask(test_points, radius):
return (test_points[0, :]**2 + test_points[1, :]**2 > radius**2)
def outside_circle(test_points, radius):
mask = circle_mask(test_points, radius)
return np.array([row[mask] for row in test_points])
eval_points = outside_circle(eval_points, radius=circle_rad)
from pytential.target import PointsTarget
vel = bind((qbx, PointsTarget(eval_points)),
representation_sym)(queue,
sigma=sigma,
mu=mu,
normal=normal,
sigma_int_val=int_val,
omega=omega)
print("@@@@@@@@")
fplot = FieldPlotter(np.zeros(2), extent=6, npoints=100)
plot_pts = outside_circle(fplot.points, radius=circle_rad)
plot_vel = bind((qbx, PointsTarget(plot_pts)),
representation_sym)(queue,
sigma=sigma,
mu=mu,
normal=normal,
sigma_int_val=int_val,
omega=omega)
def get_obj_array(obj_array):
return make_obj_array([ary.get() for ary in obj_array])
exact_soln = fund_and_rot_soln(cl.array.to_device(queue, eval_points[0]),
cl.array.to_device(queue, eval_points[1]),
fund_soln_loc, strength)
vel = get_obj_array(vel)
err = vel - get_obj_array(exact_soln)
# FIXME: Pointwise relative errors don't make sense!
rel_err = err / (get_obj_array(exact_soln))
if 0:
print("@@@@@@@@")
print("vel[0], err[0], rel_err[0] ***** vel[1], err[1], rel_err[1]: ")
for i in range(len(vel[0])):
print("%15.8e, %15.8e, %15.8e ***** %15.8e, %15.8e, %15.8e\n" %
(vel[0][i], err[0][i], rel_err[0][i], vel[1][i], err[1][i],
rel_err[1][i]))
print("@@@@@@@@")
l2_err = np.sqrt((6. / (nsamp - 1))**2 * np.sum(err[0] * err[0]) +
(6. / (nsamp - 1))**2 * np.sum(err[1] * err[1]))
l2_rel_err = np.sqrt((6. /
(nsamp - 1))**2 * np.sum(rel_err[0] * rel_err[0]) +
(6. /
(nsamp - 1))**2 * np.sum(rel_err[1] * rel_err[1]))
print("L2 error estimate: ", l2_err)
print("L2 rel error estimate: ", l2_rel_err)
print("max error at sampled points: ", max(abs(err[0])), max(abs(err[1])))
print("max rel error at sampled points: ", max(abs(rel_err[0])),
max(abs(rel_err[1])))
if do_plot:
import matplotlib
matplotlib.use("Agg")
import matplotlib.pyplot as plt
full_pot = np.zeros_like(fplot.points) * float("nan")
mask = circle_mask(fplot.points, radius=circle_rad)
for i, vel in enumerate(plot_vel):
full_pot[i, mask] = vel.get()
plt.quiver(fplot.points[0],
fplot.points[1],
full_pot[0],
full_pot[1],
linewidth=0.1)
plt.savefig("exterior-2d-field.pdf")
# }}}
h_max = bind(qbx, sym.h_max(qbx.ambient_dim))(queue)
return h_max, l2_err
def test_ellipse_eigenvalues(ctx_getter, ellipse_aspect, mode_nr, qbx_order):
logging.basicConfig(level=logging.INFO)
print("ellipse_aspect: %s, mode_nr: %d, qbx_order: %d" % (
ellipse_aspect, mode_nr, qbx_order))
cl_ctx = ctx_getter()
queue = cl.CommandQueue(cl_ctx)
target_order = 7
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
InterpolatoryQuadratureSimplexGroupFactory
from pytential.qbx import QBXLayerPotentialSource
from pytools.convergence import EOCRecorder
s_eoc_rec = EOCRecorder()
d_eoc_rec = EOCRecorder()
sp_eoc_rec = EOCRecorder()
if ellipse_aspect != 1:
nelements_values = [60, 100, 150, 200]
else:
nelements_values = [30, 70]
# See
#
# [1] G. J. Rodin and O. Steinbach, "Boundary Element Preconditioners
# for Problems Defined on Slender Domains", SIAM Journal on Scientific
# Computing, Vol. 24, No. 4, pg. 1450, 2003.
# http://dx.doi.org/10.1137/S1064827500372067
for nelements in nelements_values:
mesh = make_curve_mesh(partial(ellipse, ellipse_aspect),
np.linspace(0, 1, nelements+1),
target_order)
fmm_order = qbx_order
if fmm_order > 3:
# FIXME: for now
fmm_order = False
density_discr = Discretization(
cl_ctx, mesh,
InterpolatoryQuadratureSimplexGroupFactory(target_order))
qbx = QBXLayerPotentialSource(density_discr, 4*target_order,
qbx_order, fmm_order=fmm_order)
nodes = density_discr.nodes().with_queue(queue)
if 0:
# plot geometry, centers, normals
centers = qbx.centers(density_discr, 1)
nodes_h = nodes.get()
centers_h = [centers[0].get(), centers[1].get()]
pt.plot(nodes_h[0], nodes_h[1], "x-")
pt.plot(centers_h[0], centers_h[1], "o")
normal = bind(qbx, sym.normal())(queue).as_vector(np.object)
pt.quiver(nodes_h[0], nodes_h[1],
normal[0].get(), normal[1].get())
pt.gca().set_aspect("equal")
pt.show()
angle = cl.clmath.atan2(nodes[1]*ellipse_aspect, nodes[0])
ellipse_fraction = ((1-ellipse_aspect)/(1+ellipse_aspect))**mode_nr
# (2.6) in [1]
J = cl.clmath.sqrt( # noqa
cl.clmath.sin(angle)**2
+ (1/ellipse_aspect)**2 * cl.clmath.cos(angle)**2)
# {{{ single layer
sigma = cl.clmath.cos(mode_nr*angle)/J
s_sigma_op = bind(qbx, sym.S(0, sym.var("sigma")))
s_sigma = s_sigma_op(queue=queue, sigma=sigma)
# SIGN BINGO! :)
s_eigval = 1/(2*mode_nr) * (1 + (-1)**mode_nr * ellipse_fraction)
# (2.12) in [1]
s_sigma_ref = s_eigval*J*sigma
if 0:
#pt.plot(s_sigma.get(), label="result")
#pt.plot(s_sigma_ref.get(), label="ref")
pt.plot((s_sigma_ref-s_sigma).get(), label="err")
pt.legend()
pt.show()
s_err = (
norm(density_discr, queue, s_sigma - s_sigma_ref)
/
norm(density_discr, queue, s_sigma_ref))
s_eoc_rec.add_data_point(1/nelements, s_err)
# }}}
# {{{ double layer
sigma = cl.clmath.cos(mode_nr*angle)
d_sigma_op = bind(qbx, sym.D(0, sym.var("sigma")))
d_sigma = d_sigma_op(queue=queue, sigma=sigma)
# SIGN BINGO! :)
d_eigval = -(-1)**mode_nr * 1/2*ellipse_fraction
d_sigma_ref = d_eigval*sigma
if 0:
pt.plot(d_sigma.get(), label="result")
pt.plot(d_sigma_ref.get(), label="ref")
pt.legend()
pt.show()
if ellipse_aspect == 1:
d_ref_norm = norm(density_discr, queue, sigma)
else:
d_ref_norm = norm(density_discr, queue, d_sigma_ref)
d_err = (
norm(density_discr, queue, d_sigma - d_sigma_ref)
/
d_ref_norm)
d_eoc_rec.add_data_point(1/nelements, d_err)
# }}}
if ellipse_aspect == 1:
# {{{ S'
sigma = cl.clmath.cos(mode_nr*angle)
sp_sigma_op = bind(qbx, sym.Sp(0, sym.var("sigma")))
sp_sigma = sp_sigma_op(queue=queue, sigma=sigma)
sp_eigval = 0
sp_sigma_ref = sp_eigval*sigma
sp_err = (
norm(density_discr, queue, sp_sigma - sp_sigma_ref)
/
norm(density_discr, queue, sigma))
sp_eoc_rec.add_data_point(1/nelements, sp_err)
# }}}
print("Errors for S:")
print(s_eoc_rec)
required_order = qbx_order + 1
assert s_eoc_rec.order_estimate() > required_order - 1.5
print("Errors for D:")
print(d_eoc_rec)
required_order = qbx_order
assert d_eoc_rec.order_estimate() > required_order - 1.5
if ellipse_aspect == 1:
print("Errors for S':")
print(sp_eoc_rec)
required_order = qbx_order
assert sp_eoc_rec.order_estimate() > required_order - 1.5
def test_sanity_single_element(ctx_getter, dim, order, visualize=False):
pytest.importorskip("pytential")
cl_ctx = ctx_getter()
queue = cl.CommandQueue(cl_ctx)
from modepy.tools import UNIT_VERTICES
vertices = UNIT_VERTICES[dim].T.copy()
center = np.empty(dim, np.float64)
center.fill(-0.5)
import modepy as mp
from meshmode.mesh import SimplexElementGroup, Mesh
mg = SimplexElementGroup(
order=order,
vertex_indices=np.arange(dim+1, dtype=np.int32).reshape(1, -1),
nodes=mp.warp_and_blend_nodes(dim, order).reshape(dim, 1, -1),
dim=dim)
mesh = Mesh(vertices, [mg])
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
PolynomialWarpAndBlendGroupFactory
vol_discr = Discretization(cl_ctx, mesh,
PolynomialWarpAndBlendGroupFactory(order+3))
# {{{ volume calculation check
vol_x = vol_discr.nodes().with_queue(queue)
vol_one = vol_x[0].copy()
vol_one.fill(1)
from pytential import norm, integral # noqa
from pytools import factorial
true_vol = 1/factorial(dim) * 2**dim
comp_vol = integral(vol_discr, queue, vol_one)
rel_vol_err = abs(true_vol - comp_vol) / true_vol
assert rel_vol_err < 1e-12
# }}}
# {{{ boundary discretization
from meshmode.discretization.connection import make_boundary_restriction
bdry_mesh, bdry_discr, bdry_connection = make_boundary_restriction(
queue, vol_discr, PolynomialWarpAndBlendGroupFactory(order + 3))
# }}}
# {{{ visualizers
from meshmode.discretization.visualization import make_visualizer
#vol_vis = make_visualizer(queue, vol_discr, 4)
bdry_vis = make_visualizer(queue, bdry_discr, 4)
# }}}
from pytential import bind, sym
bdry_normals = bind(bdry_discr, sym.normal())(queue).as_vector(dtype=object)
if visualize:
bdry_vis.write_vtk_file("boundary.vtu", [
("bdry_normals", bdry_normals)
])
from pytential import bind, sym
normal_outward_check = bind(bdry_discr,
sym.normal()
|
(sym.Nodes() + 0.5*sym.ones_vec(dim)),
)(queue).as_scalar() > 0
assert normal_outward_check.get().all(), normal_outward_check.get()
def run_int_eq_test(
cl_ctx, queue, curve_f, nelements, qbx_order, bc_type, loc_sign, k,
target_order, source_order):
mesh = make_curve_mesh(curve_f,
np.linspace(0, 1, nelements+1),
target_order)
if 0:
from pytential.visualization import show_mesh
show_mesh(mesh)
pt.gca().set_aspect("equal")
pt.show()
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))
if source_order is None:
source_order = 4*target_order
qbx = QBXLayerPotentialSource(
density_discr, fine_order=source_order, qbx_order=qbx_order,
# Don't use FMM for now
fmm_order=False)
# {{{ set up operator
from pytential.symbolic.pde.scalar import (
DirichletOperator,
NeumannOperator)
from sumpy.kernel import LaplaceKernel, HelmholtzKernel, AxisTargetDerivative
if k:
knl = HelmholtzKernel(2)
knl_kwargs = {"k": k}
else:
knl = LaplaceKernel(2)
knl_kwargs = {}
if knl.is_complex_valued:
dtype = np.complex128
else:
dtype = np.float64
if bc_type == "dirichlet":
op = DirichletOperator((knl, knl_kwargs), loc_sign, use_l2_weighting=True)
elif bc_type == "neumann":
op = NeumannOperator((knl, knl_kwargs), loc_sign, use_l2_weighting=True,
use_improved_operator=False)
else:
assert False
op_u = op.operator(sym.var("u"))
# }}}
# {{{ set up test data
inner_radius = 0.1
outer_radius = 2
if loc_sign < 0:
test_src_geo_radius = outer_radius
test_tgt_geo_radius = inner_radius
else:
test_src_geo_radius = inner_radius
test_tgt_geo_radius = outer_radius
point_sources = make_circular_point_group(10, test_src_geo_radius,
func=lambda x: x**1.5)
test_targets = make_circular_point_group(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
# }}}
if 0:
# 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())(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()
# {{{ establish BCs
from sumpy.p2p import P2P
pot_p2p = P2P(cl_ctx,
[knl], exclude_self=False, value_dtypes=dtype)
evt, (test_direct,) = pot_p2p(
queue, test_targets, point_sources, [source_charges],
out_host=False, **knl_kwargs)
nodes = density_discr.nodes()
evt, (src_pot,) = pot_p2p(
queue, nodes, point_sources, [source_charges],
**knl_kwargs)
grad_p2p = P2P(cl_ctx,
[AxisTargetDerivative(0, knl), AxisTargetDerivative(1, knl)],
exclude_self=False, value_dtypes=dtype)
evt, (src_grad0, src_grad1) = grad_p2p(
queue, nodes, point_sources, [source_charges],
**knl_kwargs)
if bc_type == "dirichlet":
bc = src_pot
elif bc_type == "neumann":
normal = bind(density_discr, sym.normal())(queue).as_vector(np.object)
bc = (src_grad0*normal[0] + src_grad1*normal[1])
# }}}
# {{{ solve
bound_op = bind(qbx, op_u)
rhs = bind(density_discr, op.prepare_rhs(sym.var("bc")))(queue, bc=bc)
from pytential.solve import gmres
gmres_result = gmres(
bound_op.scipy_op(queue, "u", k=k),
rhs, tol=1e-14, progress=True,
hard_failure=False)
u = gmres_result.solution
print("gmres state:", gmres_result.state)
if 0:
# {{{ build matrix for spectrum check
from sumpy.tools import build_matrix
mat = build_matrix(bound_op.scipy_op("u"))
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()
# }}}
# }}}
# {{{ error check
from pytential.target import PointsTarget
bound_tgt_op = bind((qbx, PointsTarget(test_targets)),
op.representation(sym.var("u")))
test_via_bdry = bound_tgt_op(queue, u=u, k=k)
err = test_direct-test_via_bdry
err = err.get()
test_direct = test_direct.get()
test_via_bdry = test_via_bdry.get()
# {{{ remove effect of net source charge
if k == 0 and 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))
# {{{ test tangential derivative
bound_t_deriv_op = bind(qbx,
op.representation(
sym.var("u"), map_potentials=sym.tangential_derivative,
qbx_forced_limit=loc_sign))
#print(bound_t_deriv_op.code)
tang_deriv_from_src = bound_t_deriv_op(queue, u=u).as_scalar().get()
tangent = bind(
density_discr,
sym.pseudoscalar()/sym.area_element())(queue).as_vector(np.object)
tang_deriv_ref = (src_grad0 * tangent[0] + src_grad1 * tangent[1]).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)
# }}}
# {{{ plotting
if 0:
fplot = FieldPlotter(np.zeros(2),
extent=1.25*2*max(test_src_geo_radius, test_tgt_geo_radius),
npoints=200)
#pt.plot(u)
#pt.show()
evt, (fld_from_src,) = pot_p2p(
queue, fplot.points, point_sources, [source_charges],
**knl_kwargs)
fld_from_bdry = bind(
(qbx, PointsTarget(fplot.points)),
op.representation(sym.var("u"))
)(queue, u=u, k=k)
fld_from_src = fld_from_src.get()
fld_from_bdry = fld_from_bdry.get()
nodes = density_discr.nodes().get(queue=queue)
def prep():
pt.plot(point_sources[0], point_sources[1], "o",
label="Monopole 'Point Charges'")
pt.plot(test_targets[0], test_targets[1], "v",
label="Observation Points")
pt.plot(nodes[0], nodes[1], "k-",
label=r"$\Gamma$")
from matplotlib.cm import get_cmap
cmap = get_cmap()
cmap._init()
if 0:
cmap._lut[(cmap.N*99)//100:, -1] = 0 # make last percent transparent?
prep()
if 1:
pt.subplot(131)
pt.title("Field error (loc_sign=%s)" % loc_sign)
log_err = np.log10(1e-20+np.abs(fld_from_src-fld_from_bdry))
log_err = np.minimum(-3, log_err)
fplot.show_scalar_in_matplotlib(log_err, cmap=cmap)
#from matplotlib.colors import Normalize
#im.set_norm(Normalize(vmin=-6, vmax=1))
cb = pt.colorbar(shrink=0.9)
cb.set_label(r"$\log_{10}(\mathdefault{Error})$")
if 1:
pt.subplot(132)
prep()
pt.title("Source Field")
fplot.show_scalar_in_matplotlib(
fld_from_src.real, max_val=3)
pt.colorbar(shrink=0.9)
if 1:
pt.subplot(133)
prep()
pt.title("Solved Field")
fplot.show_scalar_in_matplotlib(
fld_from_bdry.real, max_val=3)
pt.colorbar(shrink=0.9)
# total field
#fplot.show_scalar_in_matplotlib(
#fld_from_src.real+fld_from_bdry.real, max_val=0.1)
#pt.colorbar()
pt.legend(loc="best", prop=dict(size=15))
from matplotlib.ticker import NullFormatter
pt.gca().xaxis.set_major_formatter(NullFormatter())
pt.gca().yaxis.set_major_formatter(NullFormatter())
pt.gca().set_aspect("equal")
if 0:
border_factor_top = 0.9
border_factor = 0.3
xl, xh = pt.xlim()
xhsize = 0.5*(xh-xl)
pt.xlim(xl-border_factor*xhsize, xh+border_factor*xhsize)
yl, yh = pt.ylim()
yhsize = 0.5*(yh-yl)
pt.ylim(yl-border_factor_top*yhsize, yh+border_factor*yhsize)
#pt.savefig("helmholtz.pdf", dpi=600)
pt.show()
# }}}
class Result(Record):
pass
return Result(
rel_err_2=rel_err_2,
rel_err_inf=rel_err_inf,
rel_td_err_inf=rel_td_err_inf,
gmres_result=gmres_result)
def centers(self, target_discr, sign):
from pytential import sym, bind
with cl.CommandQueue(self.cl_context) as queue:
return bind(target_discr,
sym.Nodes() + 2*sign*sym.area_element()*sym.normal())(queue) \
.as_vector(np.object)
def test_identities(ctx_getter, zero_op_name, curve_name, curve_f, qbx_order, k):
cl_ctx = ctx_getter()
queue = cl.CommandQueue(cl_ctx)
# prevent cache 'splosion
from sympy.core.cache import clear_cache
clear_cache()
target_order = 7
u_sym = sym.var("u")
grad_u_sym = sym.VectorVariable("grad_u")
dn_u_sym = sym.var("dn_u")
if k == 0:
k_sym = 0
else:
k_sym = "k"
zero_op_table = {
"green":
sym.S(k_sym, dn_u_sym) - sym.D(k_sym, u_sym) - 0.5*u_sym,
"green_grad":
d1.nabla * d1(sym.S(k_sym, dn_u_sym))
- d2.nabla * d2(sym.D(k_sym, u_sym))
- 0.5*grad_u_sym,
# only for k==0:
"zero_calderon":
-sym.Dp(0, sym.S(0, u_sym))
- 0.25*u_sym + sym.Sp(0, sym.Sp(0, u_sym))
}
order_table = {
"green": qbx_order,
"green_grad": qbx_order-1,
"zero_calderon": qbx_order-1,
}
zero_op = zero_op_table[zero_op_name]
from pytools.convergence import EOCRecorder
eoc_rec = EOCRecorder()
for nelements in [30, 50, 70]:
mesh = make_curve_mesh(curve_f,
np.linspace(0, 1, nelements+1),
target_order)
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
InterpolatoryQuadratureSimplexGroupFactory
from pytential.qbx import QBXLayerPotentialSource
density_discr = Discretization(
cl_ctx, mesh,
InterpolatoryQuadratureSimplexGroupFactory(target_order))
qbx = QBXLayerPotentialSource(density_discr, 4*target_order,
qbx_order,
# Don't use FMM for now
fmm_order=False)
# {{{ compute values of a solution to the PDE
nodes_host = density_discr.nodes().get(queue)
normal = bind(density_discr, sym.normal())(queue).as_vector(np.object)
normal_host = [normal[0].get(), normal[1].get()]
if k != 0:
angle = 0.3
wave_vec = np.array([np.cos(angle), np.sin(angle)])
u = np.exp(1j*k*np.tensordot(wave_vec, nodes_host, axes=1))
grad_u = 1j*k*wave_vec[:, np.newaxis]*u
else:
center = np.array([3, 1])
diff = nodes_host - center[:, np.newaxis]
dist_squared = np.sum(diff**2, axis=0)
dist = np.sqrt(dist_squared)
u = np.log(dist)
grad_u = diff/dist_squared
dn_u = normal_host[0]*grad_u[0] + normal_host[1]*grad_u[1]
# }}}
u_dev = cl.array.to_device(queue, u)
dn_u_dev = cl.array.to_device(queue, dn_u)
grad_u_dev = cl.array.to_device(queue, grad_u)
key = (qbx_order, curve_name, nelements, zero_op_name)
bound_op = bind(qbx, zero_op)
error = bound_op(
queue, u=u_dev, dn_u=dn_u_dev, grad_u=grad_u_dev, k=k)
if 0:
pt.plot(error)
pt.show()
l2_error_norm = norm(density_discr, queue, error)
print(key, l2_error_norm)
eoc_rec.add_data_point(1/nelements, l2_error_norm)
print(eoc_rec)
tgt_order = order_table[zero_op_name]
assert eoc_rec.order_estimate() > tgt_order - 1.3
def test_sanity_balls(actx_factory,
src_file,
dim,
mesh_order,
visualize=False):
pytest.importorskip("pytential")
logging.basicConfig(level=logging.INFO)
actx = actx_factory()
from pytools.convergence import EOCRecorder
vol_eoc_rec = EOCRecorder()
surf_eoc_rec = EOCRecorder()
# overkill
quad_order = mesh_order
from pytential import bind, sym
for h in [0.2, 0.1, 0.05]:
from meshmode.mesh.io import generate_gmsh, FileSource
mesh = generate_gmsh(FileSource(src_file),
dim,
order=mesh_order,
other_options=[
"-string",
"Mesh.CharacteristicLengthMax = %g;" % h
],
force_ambient_dim=dim,
target_unit="MM")
logger.info("%d elements", mesh.nelements)
# {{{ discretizations and connections
from meshmode.discretization import Discretization
vol_discr = Discretization(
actx, mesh, InterpolatoryQuadratureSimplexGroupFactory(quad_order))
from meshmode.discretization.connection import make_face_restriction
bdry_connection = make_face_restriction(
actx, vol_discr,
InterpolatoryQuadratureSimplexGroupFactory(quad_order), BTAG_ALL)
bdry_discr = bdry_connection.to_discr
# }}}
from math import gamma
true_surf = 2 * np.pi**(dim / 2) / gamma(dim / 2)
true_vol = true_surf / dim
vol_x = thaw(vol_discr.nodes(), actx)
vol_one = vol_x[0] * 0 + 1
from pytential import norm, integral # noqa
comp_vol = integral(vol_discr, vol_one)
rel_vol_err = abs(true_vol - comp_vol) / true_vol
vol_eoc_rec.add_data_point(h, rel_vol_err)
print("VOL", true_vol, comp_vol)
bdry_x = thaw(bdry_discr.nodes(), actx)
bdry_one_exact = bdry_x[0] * 0 + 1
bdry_one = bdry_connection(vol_one)
intp_err = norm(bdry_discr, bdry_one - bdry_one_exact)
assert intp_err < 1e-14
comp_surf = integral(bdry_discr, bdry_one)
rel_surf_err = abs(true_surf - comp_surf) / true_surf
surf_eoc_rec.add_data_point(h, rel_surf_err)
print("SURF", true_surf, comp_surf)
if visualize:
from meshmode.discretization.visualization import make_visualizer
vol_vis = make_visualizer(actx, vol_discr, 7)
bdry_vis = make_visualizer(actx, bdry_discr, 7)
name = src_file.split("-")[0]
vol_vis.write_vtk_file(f"sanity_balls_volume_{name}_{h:g}.vtu", [
("f", vol_one),
("area_el",
bind(vol_discr,
sym.area_element(mesh.ambient_dim,
mesh.ambient_dim))(actx)),
])
bdry_vis.write_vtk_file(f"sanity_balls_boundary_{name}_{h:g}.vtu",
[("f", bdry_one)])
# {{{ check normals point outward
normal_outward_check = bind(
bdry_discr,
sym.normal(mesh.ambient_dim) | sym.nodes(mesh.ambient_dim),
)(actx).as_scalar()
normal_outward_check = flatten_to_numpy(actx, normal_outward_check > 0)
assert normal_outward_check.all(), normal_outward_check
# }}}
print("---------------------------------")
print("VOLUME")
print("---------------------------------")
print(vol_eoc_rec)
assert vol_eoc_rec.order_estimate() >= mesh_order
print("---------------------------------")
print("SURFACE")
print("---------------------------------")
print(surf_eoc_rec)
assert surf_eoc_rec.order_estimate() >= mesh_order
def run_dielectric_test(cl_ctx,
queue,
nelements,
qbx_order,
op_class,
mode,
k0=3,
k1=2.9,
mesh_order=10,
bdry_quad_order=None,
bdry_ovsmp_quad_order=None,
use_l2_weighting=False,
fmm_order=None,
visualize=False):
if fmm_order is None:
fmm_order = qbx_order * 2
if bdry_quad_order is None:
bdry_quad_order = mesh_order
if bdry_ovsmp_quad_order is None:
bdry_ovsmp_quad_order = 4 * bdry_quad_order
from meshmode.mesh.generation import ellipse, make_curve_mesh
from functools import partial
mesh = make_curve_mesh(partial(ellipse, 3),
np.linspace(0, 1, nelements + 1), mesh_order)
density_discr = Discretization(
cl_ctx, mesh,
InterpolatoryQuadratureSimplexGroupFactory(bdry_quad_order))
logger.info("%d elements" % mesh.nelements)
# from meshmode.discretization.visualization import make_visualizer
# bdry_vis = make_visualizer(queue, density_discr, 20)
# {{{ solve bvp
from sumpy.kernel import HelmholtzKernel, AxisTargetDerivative
kernel = HelmholtzKernel(2)
beta = 2.5
K0 = np.sqrt(k0**2 - beta**2) # noqa
K1 = np.sqrt(k1**2 - beta**2) # noqa
pde_op = op_class(mode,
k_vacuum=1,
interfaces=((0, 1, sym.DEFAULT_SOURCE), ),
domain_k_exprs=(k0, k1),
beta=beta,
use_l2_weighting=use_l2_weighting)
op_unknown_sym = pde_op.make_unknown("unknown")
representation0_sym = pde_op.representation(op_unknown_sym, 0)
representation1_sym = pde_op.representation(op_unknown_sym, 1)
from pytential.qbx import QBXLayerPotentialSource
qbx = QBXLayerPotentialSource(density_discr,
fine_order=bdry_ovsmp_quad_order,
qbx_order=qbx_order,
fmm_order=fmm_order).with_refinement()
#print(sym.pretty(pde_op.operator(op_unknown_sym)))
#1/0
bound_pde_op = bind(qbx, pde_op.operator(op_unknown_sym))
e_factor = float(pde_op.ez_enabled)
h_factor = float(pde_op.hz_enabled)
e_sources_0 = make_obj_array(list(np.array([[0.1, 0.2]]).T.copy()))
e_strengths_0 = np.array([1 * e_factor])
e_sources_1 = make_obj_array(list(np.array([[4, 4]]).T.copy()))
e_strengths_1 = np.array([1 * e_factor])
h_sources_0 = make_obj_array(list(np.array([[0.2, 0.1]]).T.copy()))
h_strengths_0 = np.array([1 * h_factor])
h_sources_1 = make_obj_array(list(np.array([[4, 5]]).T.copy()))
h_strengths_1 = np.array([1 * h_factor])
kernel_grad = [
AxisTargetDerivative(i, kernel)
for i in range(density_discr.ambient_dim)
]
from sumpy.p2p import P2P
pot_p2p = P2P(cl_ctx, [kernel], exclude_self=False)
pot_p2p_grad = P2P(cl_ctx, kernel_grad, exclude_self=False)
normal = bind(density_discr, sym.normal())(queue).as_vector(np.object)
tangent = bind(density_discr,
sym.pseudoscalar() / sym.area_element())(queue).as_vector(
np.object)
_, (E0, ) = pot_p2p(queue,
density_discr.nodes(),
e_sources_0, [e_strengths_0],
out_host=False,
k=K0)
_, (E1, ) = pot_p2p(queue,
density_discr.nodes(),
e_sources_1, [e_strengths_1],
out_host=False,
k=K1)
_, (grad0_E0, grad1_E0) = pot_p2p_grad(queue,
density_discr.nodes(),
e_sources_0, [e_strengths_0],
out_host=False,
k=K0)
_, (grad0_E1, grad1_E1) = pot_p2p_grad(queue,
density_discr.nodes(),
e_sources_1, [e_strengths_1],
out_host=False,
k=K1)
_, (H0, ) = pot_p2p(queue,
density_discr.nodes(),
h_sources_0, [h_strengths_0],
out_host=False,
k=K0)
_, (H1, ) = pot_p2p(queue,
density_discr.nodes(),
h_sources_1, [h_strengths_1],
out_host=False,
k=K1)
_, (grad0_H0, grad1_H0) = pot_p2p_grad(queue,
density_discr.nodes(),
h_sources_0, [h_strengths_0],
out_host=False,
k=K0)
_, (grad0_H1, grad1_H1) = pot_p2p_grad(queue,
density_discr.nodes(),
h_sources_1, [h_strengths_1],
out_host=False,
k=K1)
E0_dntarget = (grad0_E0 * normal[0] + grad1_E0 * normal[1]) # noqa
E1_dntarget = (grad0_E1 * normal[0] + grad1_E1 * normal[1]) # noqa
H0_dntarget = (grad0_H0 * normal[0] + grad1_H0 * normal[1]) # noqa
H1_dntarget = (grad0_H1 * normal[0] + grad1_H1 * normal[1]) # noqa
E0_dttarget = (grad0_E0 * tangent[0] + grad1_E0 * tangent[1]) # noqa
E1_dttarget = (grad0_E1 * tangent[0] + grad1_E1 * tangent[1]) # noqa
H0_dttarget = (grad0_H0 * tangent[0] + grad1_H0 * tangent[1]) # noqa
H1_dttarget = (grad0_H1 * tangent[0] + grad1_H1 * tangent[1]) # noqa
sqrt_w = bind(density_discr, sym.sqrt_jac_q_weight())(queue)
bvp_rhs = np.zeros(len(pde_op.bcs), dtype=np.object)
for i_bc, terms in enumerate(pde_op.bcs):
for term in terms:
assert term.i_interface == 0
if term.field_kind == pde_op.field_kind_e:
if term.direction == pde_op.dir_none:
bvp_rhs[i_bc] += (term.coeff_outer * E0 +
term.coeff_inner * E1)
elif term.direction == pde_op.dir_normal:
bvp_rhs[i_bc] += (term.coeff_outer * E0_dntarget +
term.coeff_inner * E1_dntarget)
elif term.direction == pde_op.dir_tangential:
bvp_rhs[i_bc] += (term.coeff_outer * E0_dttarget +
term.coeff_inner * E1_dttarget)
else:
raise NotImplementedError("direction spec in RHS")
elif term.field_kind == pde_op.field_kind_h:
if term.direction == pde_op.dir_none:
bvp_rhs[i_bc] += (term.coeff_outer * H0 +
term.coeff_inner * H1)
elif term.direction == pde_op.dir_normal:
bvp_rhs[i_bc] += (term.coeff_outer * H0_dntarget +
term.coeff_inner * H1_dntarget)
elif term.direction == pde_op.dir_tangential:
bvp_rhs[i_bc] += (term.coeff_outer * H0_dttarget +
term.coeff_inner * H1_dttarget)
else:
raise NotImplementedError("direction spec in RHS")
if use_l2_weighting:
bvp_rhs[i_bc] *= sqrt_w
scipy_op = bound_pde_op.scipy_op(queue,
"unknown",
domains=[sym.DEFAULT_TARGET] *
len(pde_op.bcs),
K0=K0,
K1=K1,
dtype=np.complex128)
if mode == "tem" or op_class is SRep:
from sumpy.tools import vector_from_device, vector_to_device
from pytential.solve import lu
unknown = lu(scipy_op, vector_from_device(queue, bvp_rhs))
unknown = vector_to_device(queue, unknown)
else:
from pytential.solve import gmres
gmres_result = gmres(scipy_op,
bvp_rhs,
tol=1e-14,
progress=True,
hard_failure=True,
stall_iterations=0)
unknown = gmres_result.solution
# }}}
targets_0 = make_obj_array(
list(np.array([[3.2 + t, -4] for t in [0, 0.5, 1]]).T.copy()))
targets_1 = make_obj_array(
list(np.array([[t * -0.3, t * -0.2] for t in [0, 0.5, 1]]).T.copy()))
from pytential.target import PointsTarget
from sumpy.tools import vector_from_device
F0_tgt = vector_from_device(
queue,
bind( # noqa
(qbx, PointsTarget(targets_0)),
representation0_sym)(queue, unknown=unknown, K0=K0, K1=K1))
F1_tgt = vector_from_device(
queue,
bind( # noqa
(qbx, PointsTarget(targets_1)),
representation1_sym)(queue, unknown=unknown, K0=K0, K1=K1))
_, (E0_tgt_true, ) = pot_p2p(queue,
targets_0,
e_sources_0, [e_strengths_0],
out_host=True,
k=K0)
_, (E1_tgt_true, ) = pot_p2p(queue,
targets_1,
e_sources_1, [e_strengths_1],
out_host=True,
k=K1)
_, (H0_tgt_true, ) = pot_p2p(queue,
targets_0,
h_sources_0, [h_strengths_0],
out_host=True,
k=K0)
_, (H1_tgt_true, ) = pot_p2p(queue,
targets_1,
h_sources_1, [h_strengths_1],
out_host=True,
k=K1)
err_F0_total = 0 # noqa
err_F1_total = 0 # noqa
i_field = 0
def vec_norm(ary):
return la.norm(ary.reshape(-1))
def field_kind_to_string(field_kind):
return {pde_op.field_kind_e: "E", pde_op.field_kind_h: "H"}[field_kind]
for field_kind in pde_op.field_kinds:
if not pde_op.is_field_present(field_kind):
continue
if field_kind == pde_op.field_kind_e:
F0_tgt_true = E0_tgt_true # noqa
F1_tgt_true = E1_tgt_true # noqa
elif field_kind == pde_op.field_kind_h:
F0_tgt_true = H0_tgt_true # noqa
F1_tgt_true = H1_tgt_true # noqa
else:
assert False
abs_err_F0 = vec_norm(F0_tgt[i_field] - F0_tgt_true) # noqa
abs_err_F1 = vec_norm(F1_tgt[i_field] - F1_tgt_true) # noqa
rel_err_F0 = abs_err_F0 / vec_norm(F0_tgt_true) # noqa
rel_err_F1 = abs_err_F1 / vec_norm(F1_tgt_true) # noqa
err_F0_total = max(rel_err_F0, err_F0_total) # noqa
err_F1_total = max(rel_err_F1, err_F1_total) # noqa
print("Abs Err %s0" % field_kind_to_string(field_kind), abs_err_F0)
print("Abs Err %s1" % field_kind_to_string(field_kind), abs_err_F1)
print("Rel Err %s0" % field_kind_to_string(field_kind), rel_err_F0)
print("Rel Err %s1" % field_kind_to_string(field_kind), rel_err_F1)
i_field += 1
if visualize:
from sumpy.visualization import FieldPlotter
fplot = FieldPlotter(np.zeros(2), extent=5, npoints=300)
from pytential.target import PointsTarget
fld0 = bind((qbx, PointsTarget(fplot.points)),
representation0_sym)(queue, unknown=unknown, K0=K0)
fld1 = bind((qbx, PointsTarget(fplot.points)),
representation1_sym)(queue, unknown=unknown, K1=K1)
comp_fields = []
i_field = 0
for field_kind in pde_op.field_kinds:
if not pde_op.is_field_present(field_kind):
continue
fld_str = field_kind_to_string(field_kind)
comp_fields.extend([
("%s_fld0" % fld_str, fld0[i_field].get()),
("%s_fld1" % fld_str, fld1[i_field].get()),
])
i_field += 0
low_order_qbx = QBXLayerPotentialSource(
density_discr,
fine_order=bdry_ovsmp_quad_order,
qbx_order=2,
fmm_order=3).with_refinement()
from sumpy.kernel import LaplaceKernel
from pytential.target import PointsTarget
ones = (cl.array.empty(queue, (density_discr.nnodes, ),
dtype=np.float64).fill(1))
ind_func = -bind(
(low_order_qbx, PointsTarget(fplot.points)),
sym.D(LaplaceKernel(2), sym.var("u")))(queue, u=ones).get()
_, (e_fld0_true, ) = pot_p2p(queue,
fplot.points,
e_sources_0, [e_strengths_0],
out_host=True,
k=K0)
_, (e_fld1_true, ) = pot_p2p(queue,
fplot.points,
e_sources_1, [e_strengths_1],
out_host=True,
k=K1)
_, (h_fld0_true, ) = pot_p2p(queue,
fplot.points,
h_sources_0, [h_strengths_0],
out_host=True,
k=K0)
_, (h_fld1_true, ) = pot_p2p(queue,
fplot.points,
h_sources_1, [h_strengths_1],
out_host=True,
k=K1)
#fplot.show_scalar_in_mayavi(fld_in_vol.real, max_val=5)
fplot.write_vtk_file("potential-n%d.vts" % nelements, [
("e_fld0_true", e_fld0_true),
("e_fld1_true", e_fld1_true),
("h_fld0_true", h_fld0_true),
("h_fld1_true", h_fld1_true),
("ind", ind_func),
] + comp_fields)
return err_F0_total, err_F1_total
def test_3d_jump_relations(ctx_factory, relation, visualize=False):
# logging.basicConfig(level=logging.INFO)
cl_ctx = ctx_factory()
queue = cl.CommandQueue(cl_ctx)
if relation == "div_s":
target_order = 3
else:
target_order = 4
qbx_order = target_order
from pytools.convergence import EOCRecorder
eoc_rec = EOCRecorder()
for nel_factor in [6, 10, 14]:
from meshmode.mesh.generation import generate_torus
mesh = generate_torus(
5, 2, order=target_order,
n_outer=2*nel_factor, n_inner=nel_factor)
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
InterpolatoryQuadratureSimplexGroupFactory
pre_discr = Discretization(
cl_ctx, mesh,
InterpolatoryQuadratureSimplexGroupFactory(3))
from pytential.qbx import QBXLayerPotentialSource
qbx, _ = QBXLayerPotentialSource(
pre_discr, fine_order=4*target_order,
qbx_order=qbx_order,
fmm_order=qbx_order + 5,
fmm_backend="fmmlib"
).with_refinement()
from sumpy.kernel import LaplaceKernel
knl = LaplaceKernel(3)
def nxcurlS(qbx_forced_limit):
return sym.n_cross(sym.curl(sym.S(
knl,
sym.cse(sym.tangential_to_xyz(density_sym), "jxyz"),
qbx_forced_limit=qbx_forced_limit)))
x, y, z = qbx.density_discr.nodes().with_queue(queue)
m = cl.clmath
if relation == "nxcurls":
density_sym = sym.make_sym_vector("density", 2)
jump_identity_sym = (
nxcurlS(+1)
- (nxcurlS("avg") + 0.5*sym.tangential_to_xyz(density_sym)))
# The tangential coordinate system is element-local, so we can't just
# conjure up some globally smooth functions, interpret their values
# in the tangential coordinate system, and be done. Instead, generate
# an XYZ function and project it.
density = bind(
qbx,
sym.xyz_to_tangential(sym.make_sym_vector("jxyz", 3)))(
queue,
jxyz=sym.make_obj_array([
m.cos(0.5*x) * m.cos(0.5*y) * m.cos(0.5*z),
m.sin(0.5*x) * m.cos(0.5*y) * m.sin(0.5*z),
m.sin(0.5*x) * m.cos(0.5*y) * m.cos(0.5*z),
]))
elif relation == "sp":
density = m.cos(2*x) * m.cos(2*y) * m.cos(z)
density_sym = sym.var("density")
jump_identity_sym = (
sym.Sp(knl, density_sym, qbx_forced_limit=+1)
- (sym.Sp(knl, density_sym, qbx_forced_limit="avg")
- 0.5*density_sym))
elif relation == "div_s":
density = m.cos(2*x) * m.cos(2*y) * m.cos(z)
density_sym = sym.var("density")
jump_identity_sym = (
sym.div(sym.S(knl, sym.normal(3).as_vector()*density_sym,
qbx_forced_limit="avg"))
+ sym.D(knl, density_sym, qbx_forced_limit="avg"))
else:
raise ValueError("unexpected value of 'relation': %s" % relation)
bound_jump_identity = bind(qbx, jump_identity_sym)
jump_identity = bound_jump_identity(queue, density=density)
err = (
norm(qbx, queue, jump_identity, np.inf)
/ norm(qbx, queue, density, np.inf))
print("ERROR", qbx.h_max, err)
eoc_rec.add_data_point(qbx.h_max, err)
# {{{ visualization
if visualize and relation == "nxcurls":
nxcurlS_ext = bind(qbx, nxcurlS(+1))(queue, density=density)
nxcurlS_avg = bind(qbx, nxcurlS("avg"))(queue, density=density)
jtxyz = bind(qbx, sym.tangential_to_xyz(density_sym))(
queue, density=density)
from meshmode.discretization.visualization import make_visualizer
bdry_vis = make_visualizer(queue, qbx.density_discr, target_order+3)
bdry_normals = bind(qbx, sym.normal(3))(queue)\
.as_vector(dtype=object)
bdry_vis.write_vtk_file("source-%s.vtu" % nel_factor, [
("jt", jtxyz),
("nxcurlS_ext", nxcurlS_ext),
("nxcurlS_avg", nxcurlS_avg),
("bdry_normals", bdry_normals),
])
if visualize and relation == "sp":
sp_ext = bind(qbx, sym.Sp(knl, density_sym, qbx_forced_limit=+1))(
queue, density=density)
sp_avg = bind(qbx, sym.Sp(knl, density_sym, qbx_forced_limit="avg"))(
queue, density=density)
from meshmode.discretization.visualization import make_visualizer
bdry_vis = make_visualizer(queue, qbx.density_discr, target_order+3)
bdry_normals = bind(qbx, sym.normal(3))(queue)\
.as_vector(dtype=object)
bdry_vis.write_vtk_file("source-%s.vtu" % nel_factor, [
("density", density),
("sp_ext", sp_ext),
("sp_avg", sp_avg),
("bdry_normals", bdry_normals),
])
# }}}
print(eoc_rec)
assert eoc_rec.order_estimate() >= qbx_order - 1.5
)
places = GeometryCollection(qbx)
from pytential.qbx.refinement import refine_geometry_collection
kernel_length_scale = 5 / case.k if case.k else None
places = refine_geometry_collection(places,
kernel_length_scale=kernel_length_scale)
# {{{ compute values of a solution to the PDE
density_discr = places.get_discretization(places.auto_source.geometry)
from meshmode.dof_array import thaw, flatten, unflatten
nodes_host = [actx.to_numpy(axis)
for axis in flatten(thaw(actx, density_discr.nodes()))]
normal = bind(places, sym.normal(d))(actx).as_vector(object)
normal_host = [actx.to_numpy(axis)for axis in flatten(normal)]
if k != 0:
if d == 2:
angle = 0.3
wave_vec = np.array([np.cos(angle), np.sin(angle)])
u = np.exp(1j*k*np.tensordot(wave_vec, nodes_host, axes=1))
grad_u = 1j*k*wave_vec[:, np.newaxis]*u
elif d == 3:
center = np.array([3, 1, 2])
diff = nodes_host - center[:, np.newaxis]
r = la.norm(diff, axis=0)
u = np.exp(1j*k*r) / r
grad_u = diff * (1j*k*u/r - u/r**2)
else:
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 test_3d_jump_relations(actx_factory, relation, visualize=False):
# logging.basicConfig(level=logging.INFO)
actx = actx_factory()
if relation == "div_s":
target_order = 3
else:
target_order = 4
qbx_order = target_order
if relation == "sp":
resolutions = [10, 14, 18]
else:
resolutions = [6, 10, 14]
from pytools.convergence import EOCRecorder
eoc_rec = EOCRecorder()
for nel_factor in resolutions:
from meshmode.mesh.generation import generate_torus
mesh = generate_torus(
5,
2,
n_major=2 * nel_factor,
n_minor=nel_factor,
order=target_order,
)
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
InterpolatoryQuadratureSimplexGroupFactory
pre_density_discr = Discretization(
actx, mesh,
InterpolatoryQuadratureSimplexGroupFactory(target_order))
from pytential.qbx import QBXLayerPotentialSource
qbx = QBXLayerPotentialSource(pre_density_discr,
fine_order=5 * target_order,
qbx_order=qbx_order,
fmm_order=qbx_order + 5,
fmm_backend="fmmlib")
places = GeometryCollection(qbx)
density_discr = places.get_discretization(places.auto_source.geometry)
from sumpy.kernel import LaplaceKernel
knl = LaplaceKernel(places.ambient_dim)
def nxcurlS(qbx_forced_limit):
sigma_sym = sym.cse(sym.tangential_to_xyz(density_sym), "jxyz")
return sym.n_cross(
sym.curl(
sym.S(knl, sigma_sym, qbx_forced_limit=qbx_forced_limit)))
x, y, z = thaw(density_discr.nodes(), actx)
if relation == "nxcurls":
density_sym = sym.make_sym_vector("density", 2)
jump_identity_sym = (nxcurlS(+1) - nxcurlS("avg") -
0.5 * sym.tangential_to_xyz(density_sym))
# The tangential coordinate system is element-local, so we can't just
# conjure up some globally smooth functions, interpret their values
# in the tangential coordinate system, and be done. Instead, generate
# an XYZ function and project it.
jxyz = sym.make_obj_array([
actx.np.cos(0.5 * x) * actx.np.cos(0.5 * y) *
actx.np.cos(0.5 * z),
actx.np.sin(0.5 * x) * actx.np.cos(0.5 * y) *
actx.np.sin(0.5 * z),
actx.np.sin(0.5 * x) * actx.np.cos(0.5 * y) *
actx.np.cos(0.5 * z),
])
density = bind(
places,
sym.xyz_to_tangential(sym.make_sym_vector("jxyz",
3)))(actx, jxyz=jxyz)
elif relation == "sp":
density_sym = sym.var("density")
jump_identity_sym = (
0.5 * density_sym +
sym.Sp(knl, density_sym, qbx_forced_limit=+1) -
sym.Sp(knl, density_sym, qbx_forced_limit="avg"))
density = actx.np.cos(2 * x) * actx.np.cos(2 * y) * actx.np.cos(z)
elif relation == "div_s":
density_sym = sym.var("density")
sigma_sym = sym.normal(
places.ambient_dim).as_vector() * density_sym
jump_identity_sym = (
sym.div(sym.S(knl, sigma_sym, qbx_forced_limit="avg")) +
sym.D(knl, density_sym, qbx_forced_limit="avg"))
density = actx.np.cos(2 * x) * actx.np.cos(2 * y) * actx.np.cos(z)
else:
raise ValueError(f"unexpected value of 'relation': '{relation}'")
bound_jump_identity = bind(places, jump_identity_sym)
jump_identity = bound_jump_identity(actx, density=density)
h_max = actx.to_numpy(
bind(places, sym.h_max(places.ambient_dim))(actx))
err = actx.to_numpy(
norm(density_discr, jump_identity, np.inf) /
norm(density_discr, density, np.inf))
eoc_rec.add_data_point(h_max, err)
logging.info("error: nel %d h_max %.5e %.5e", nel_factor, h_max, err)
# {{{ visualization
if not visualize:
continue
from meshmode.discretization.visualization import make_visualizer
vis = make_visualizer(actx, density_discr, target_order)
normals = bind(places,
sym.normal(places.ambient_dim).as_vector())(actx)
error = actx.np.log10(actx.np.abs(jump_identity) + 1.0e-15)
if relation == "nxcurls":
nxcurlS_ext = bind(places, nxcurlS(+1))(actx, density=density)
nxcurlS_avg = bind(places, nxcurlS("avg"))(actx, density=density)
jtxyz = bind(places,
sym.tangential_to_xyz(density_sym))(actx,
density=density)
vis.write_vtk_file(f"source-nxcurls-{nel_factor:03d}.vtu", [
("jt", jtxyz),
("nxcurlS_ext", nxcurlS_ext),
("nxcurlS_avg", nxcurlS_avg),
("bdry_normals", normals),
("error", error),
])
elif relation == "sp":
op = sym.Sp(knl, density_sym, qbx_forced_limit=+1)
sp_ext = bind(places, op)(actx, density=density)
op = sym.Sp(knl, density_sym, qbx_forced_limit="avg")
sp_avg = bind(places, op)(actx, density=density)
vis.write_vtk_file(f"source-sp-{nel_factor:03d}.vtu", [
("density", density),
("sp_ext", sp_ext),
("sp_avg", sp_avg),
("bdry_normals", normals),
("error", error),
])
elif relation == "div_s":
vis.write_vtk_file(f"source-div-{nel_factor:03d}.vtu", [
("density", density),
("bdry_normals", normals),
("error", error),
])
# }}}
logger.info("\n%s", str(eoc_rec))
assert eoc_rec.order_estimate() >= qbx_order - 1.5
def test_sanity_balls(ctx_getter, src_file, dim, mesh_order, visualize=False):
pytest.importorskip("pytential")
logging.basicConfig(level=logging.INFO)
ctx = ctx_getter()
queue = cl.CommandQueue(ctx)
from pytools.convergence import EOCRecorder
vol_eoc_rec = EOCRecorder()
surf_eoc_rec = EOCRecorder()
# overkill
quad_order = mesh_order
from pytential import bind, sym
for h in [0.2, 0.14, 0.1]:
from meshmode.mesh.io import generate_gmsh, FileSource
mesh = generate_gmsh(FileSource(src_file),
dim,
order=mesh_order,
other_options=[
"-string",
"Mesh.CharacteristicLengthMax = %g;" % h
],
force_ambient_dim=dim)
logger.info("%d elements" % mesh.nelements)
# {{{ discretizations and connections
from meshmode.discretization import Discretization
vol_discr = Discretization(
ctx, mesh, InterpolatoryQuadratureSimplexGroupFactory(quad_order))
from meshmode.discretization.connection import make_face_restriction
bdry_connection = make_face_restriction(
vol_discr, InterpolatoryQuadratureSimplexGroupFactory(quad_order),
BTAG_ALL)
bdry_discr = bdry_connection.to_discr
# }}}
# {{{ visualizers
from meshmode.discretization.visualization import make_visualizer
vol_vis = make_visualizer(queue, vol_discr, 20)
bdry_vis = make_visualizer(queue, bdry_discr, 20)
# }}}
from math import gamma
true_surf = 2 * np.pi**(dim / 2) / gamma(dim / 2)
true_vol = true_surf / dim
vol_x = vol_discr.nodes().with_queue(queue)
vol_one = vol_x[0].copy()
vol_one.fill(1)
from pytential import norm, integral # noqa
comp_vol = integral(vol_discr, queue, vol_one)
rel_vol_err = abs(true_vol - comp_vol) / true_vol
vol_eoc_rec.add_data_point(h, rel_vol_err)
print("VOL", true_vol, comp_vol)
bdry_x = bdry_discr.nodes().with_queue(queue)
bdry_one_exact = bdry_x[0].copy()
bdry_one_exact.fill(1)
bdry_one = bdry_connection(queue, vol_one).with_queue(queue)
intp_err = norm(bdry_discr, queue, bdry_one - bdry_one_exact)
assert intp_err < 1e-14
comp_surf = integral(bdry_discr, queue, bdry_one)
rel_surf_err = abs(true_surf - comp_surf) / true_surf
surf_eoc_rec.add_data_point(h, rel_surf_err)
print("SURF", true_surf, comp_surf)
if visualize:
vol_vis.write_vtk_file("volume-h=%g.vtu" % h, [
("f", vol_one),
("area_el", bind(vol_discr, sym.area_element())(queue)),
])
bdry_vis.write_vtk_file("boundary-h=%g.vtu" % h, [("f", bdry_one)])
# {{{ check normals point outward
normal_outward_check = bind(
bdry_discr,
sym.normal(mesh.ambient_dim) | sym.nodes(mesh.ambient_dim),
)(queue).as_scalar() > 0
assert normal_outward_check.get().all(), normal_outward_check.get()
# }}}
print("---------------------------------")
print("VOLUME")
print("---------------------------------")
print(vol_eoc_rec)
assert vol_eoc_rec.order_estimate() >= mesh_order
print("---------------------------------")
print("SURFACE")
print("---------------------------------")
print(surf_eoc_rec)
assert surf_eoc_rec.order_estimate() >= mesh_order
#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))
def test_ellipse_eigenvalues(ctx_factory,
ellipse_aspect,
mode_nr,
qbx_order,
force_direct,
visualize=False):
logging.basicConfig(level=logging.INFO)
print("ellipse_aspect: %s, mode_nr: %d, qbx_order: %d" %
(ellipse_aspect, mode_nr, qbx_order))
cl_ctx = ctx_factory()
queue = cl.CommandQueue(cl_ctx)
actx = PyOpenCLArrayContext(queue)
target_order = 8
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
InterpolatoryQuadratureSimplexGroupFactory
from pytential.qbx import QBXLayerPotentialSource
from pytools.convergence import EOCRecorder
s_eoc_rec = EOCRecorder()
d_eoc_rec = EOCRecorder()
sp_eoc_rec = EOCRecorder()
if ellipse_aspect != 1:
nelements_values = [60, 100, 150, 200]
else:
nelements_values = [30, 70]
# See
#
# [1] G. J. Rodin and O. Steinbach, "Boundary Element Preconditioners
# for Problems Defined on Slender Domains", SIAM Journal on Scientific
# Computing, Vol. 24, No. 4, pg. 1450, 2003.
# https://dx.doi.org/10.1137/S1064827500372067
for nelements in nelements_values:
mesh = make_curve_mesh(partial(ellipse, ellipse_aspect),
np.linspace(0, 1, nelements + 1), target_order)
fmm_order = 12
if force_direct:
fmm_order = False
pre_density_discr = Discretization(
actx, mesh,
InterpolatoryQuadratureSimplexGroupFactory(target_order))
qbx = QBXLayerPotentialSource(
pre_density_discr,
4 * target_order,
qbx_order,
fmm_order=fmm_order,
_expansions_in_tree_have_extent=True,
)
places = GeometryCollection(qbx)
density_discr = places.get_discretization(places.auto_source.geometry)
from meshmode.dof_array import thaw, flatten
nodes = thaw(actx, density_discr.nodes())
if visualize:
# plot geometry, centers, normals
centers = bind(places, sym.expansion_centers(qbx.ambient_dim,
+1))(actx)
normals = bind(places,
sym.normal(qbx.ambient_dim))(actx).as_vector(object)
nodes_h = np.array(
[actx.to_numpy(axis) for axis in flatten(nodes)])
centers_h = np.array(
[actx.to_numpy(axis) for axis in flatten(centers)])
normals_h = np.array(
[actx.to_numpy(axis) for axis in flatten(normals)])
pt.plot(nodes_h[0], nodes_h[1], "x-")
pt.plot(centers_h[0], centers_h[1], "o")
pt.quiver(nodes_h[0], nodes_h[1], normals_h[0], normals_h[1])
pt.gca().set_aspect("equal")
pt.show()
angle = actx.np.arctan2(nodes[1] * ellipse_aspect, nodes[0])
ellipse_fraction = ((1 - ellipse_aspect) /
(1 + ellipse_aspect))**mode_nr
# (2.6) in [1]
J = actx.np.sqrt( # noqa
actx.np.sin(angle)**2 +
(1 / ellipse_aspect)**2 * actx.np.cos(angle)**2)
from sumpy.kernel import LaplaceKernel
lap_knl = LaplaceKernel(2)
# {{{ single layer
sigma_sym = sym.var("sigma")
s_sigma_op = sym.S(lap_knl, sigma_sym, qbx_forced_limit=+1)
sigma = actx.np.cos(mode_nr * angle) / J
s_sigma = bind(places, s_sigma_op)(actx, sigma=sigma)
# SIGN BINGO! :)
s_eigval = 1 / (2 * mode_nr) * (1 + (-1)**mode_nr * ellipse_fraction)
# (2.12) in [1]
s_sigma_ref = s_eigval * J * sigma
if 0:
#pt.plot(s_sigma.get(), label="result")
#pt.plot(s_sigma_ref.get(), label="ref")
pt.plot(actx.to_numpy(flatten(s_sigma_ref - s_sigma)), label="err")
pt.legend()
pt.show()
h_max = bind(places, sym.h_max(qbx.ambient_dim))(actx)
s_err = (norm(density_discr, s_sigma - s_sigma_ref) /
norm(density_discr, s_sigma_ref))
s_eoc_rec.add_data_point(h_max, s_err)
# }}}
# {{{ double layer
d_sigma_op = sym.D(lap_knl, sigma_sym, qbx_forced_limit="avg")
sigma = actx.np.cos(mode_nr * angle)
d_sigma = bind(places, d_sigma_op)(actx, sigma=sigma)
# SIGN BINGO! :)
d_eigval = -(-1)**mode_nr * 1 / 2 * ellipse_fraction
d_sigma_ref = d_eigval * sigma
if 0:
pt.plot(actx.to_numpy(flatten(d_sigma)), label="result")
pt.plot(actx.to_numpy(flatten(d_sigma_ref)), label="ref")
pt.legend()
pt.show()
if ellipse_aspect == 1:
d_ref_norm = norm(density_discr, sigma)
else:
d_ref_norm = norm(density_discr, d_sigma_ref)
d_err = (norm(density_discr, d_sigma - d_sigma_ref) / d_ref_norm)
d_eoc_rec.add_data_point(h_max, d_err)
# }}}
if ellipse_aspect == 1:
# {{{ S'
sp_sigma_op = sym.Sp(lap_knl,
sym.var("sigma"),
qbx_forced_limit="avg")
sigma = actx.np.cos(mode_nr * angle)
sp_sigma = bind(places, sp_sigma_op)(actx, sigma=sigma)
sp_eigval = 0
sp_sigma_ref = sp_eigval * sigma
sp_err = (norm(density_discr, sp_sigma - sp_sigma_ref) /
norm(density_discr, sigma))
sp_eoc_rec.add_data_point(h_max, sp_err)
# }}}
print("Errors for S:")
print(s_eoc_rec)
required_order = qbx_order + 1
assert s_eoc_rec.order_estimate() > required_order - 1.5
print("Errors for D:")
print(d_eoc_rec)
required_order = qbx_order
assert d_eoc_rec.order_estimate() > required_order - 1.5
if ellipse_aspect == 1:
print("Errors for S':")
print(sp_eoc_rec)
required_order = qbx_order
assert sp_eoc_rec.order_estimate() > required_order - 1.5
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)
def main(nelements):
import logging
logging.basicConfig(level=logging.INFO)
def get_obj_array(obj_array):
from pytools.obj_array import make_obj_array
return make_obj_array([ary.get() for ary in obj_array])
cl_ctx = cl.create_some_context()
queue = cl.CommandQueue(cl_ctx)
from meshmode.mesh.generation import ( # noqa
make_curve_mesh, starfish, ellipse, drop)
mesh = make_curve_mesh(lambda t: starfish(t),
np.linspace(0, 1, nelements + 1), target_order)
coarse_density_discr = Discretization(
cl_ctx, mesh, InterpolatoryQuadratureSimplexGroupFactory(target_order))
from pytential.qbx import QBXLayerPotentialSource
target_association_tolerance = 0.05
qbx, _ = QBXLayerPotentialSource(
coarse_density_discr,
fine_order=ovsmp_target_order,
qbx_order=qbx_order,
fmm_order=fmm_order,
target_association_tolerance=target_association_tolerance,
).with_refinement()
density_discr = qbx.density_discr
nodes = density_discr.nodes().with_queue(queue)
# Get normal vectors for the density discretization -- used in integration with stresslet
mv_normal = bind(density_discr, sym.normal(2))(queue)
normal = mv_normal.as_vector(np.object)
# {{{ describe bvp
from sumpy.kernel import LaplaceKernel
from pytential.symbolic.stokes import StressletWrapper
from pytools.obj_array import make_obj_array
dim = 2
cse = sym.cse
nvec_sym = sym.make_sym_vector("normal", dim)
sigma_sym = sym.make_sym_vector("sigma", dim)
mu_sym = sym.var("mu")
sqrt_w = sym.sqrt_jac_q_weight(2)
inv_sqrt_w_sigma = cse(sigma_sym / sqrt_w)
# -1 for interior Dirichlet
# +1 for exterior Dirichlet
loc_sign = -1
# Create stresslet object
stresslet_obj = StressletWrapper(dim=2)
# Describe boundary operator
bdry_op_sym = loc_sign * 0.5 * sigma_sym + sqrt_w * stresslet_obj.apply(
inv_sqrt_w_sigma, nvec_sym, mu_sym, qbx_forced_limit='avg')
# Bind to the qbx discretization
bound_op = bind(qbx, bdry_op_sym)
# }}}
# {{{ fix rhs and solve
def fund_soln(x, y, loc):
#with direction (1,0) for point source
r = cl.clmath.sqrt((x - loc[0])**2 + (y - loc[1])**2)
scaling = 1. / (4 * np.pi * mu)
xcomp = (-cl.clmath.log(r) + (x - loc[0])**2 / r**2) * scaling
ycomp = ((x - loc[0]) * (y - loc[1]) / r**2) * scaling
return [xcomp, ycomp]
def couette_soln(x, y, dp, h):
scaling = 1. / (2 * mu)
xcomp = scaling * dp * ((y + (h / 2.))**2 - h * (y + (h / 2.)))
ycomp = scaling * 0 * y
return [xcomp, ycomp]
if soln_type == 'fundamental':
pt_loc = np.array([2.0, 0.0])
bc = fund_soln(nodes[0], nodes[1], pt_loc)
else:
dp = -10.
h = 2.5
bc = couette_soln(nodes[0], nodes[1], dp, h)
# Get rhs vector
bvp_rhs = bind(qbx, sqrt_w * sym.make_sym_vector("bc", dim))(queue, bc=bc)
from pytential.solve import gmres
gmres_result = gmres(bound_op.scipy_op(queue,
"sigma",
np.float64,
mu=mu,
normal=normal),
bvp_rhs,
tol=1e-9,
progress=True,
stall_iterations=0,
hard_failure=True)
# }}}
# {{{ postprocess/visualize
sigma = gmres_result.solution
# Describe representation of solution for evaluation in domain
representation_sym = stresslet_obj.apply(inv_sqrt_w_sigma,
nvec_sym,
mu_sym,
qbx_forced_limit=-2)
from sumpy.visualization import FieldPlotter
nsamp = 10
eval_points_1d = np.linspace(-1., 1., nsamp)
eval_points = np.zeros((2, len(eval_points_1d)**2))
eval_points[0, :] = np.tile(eval_points_1d, len(eval_points_1d))
eval_points[1, :] = np.repeat(eval_points_1d, len(eval_points_1d))
gamma_sym = sym.var("gamma")
inv_sqrt_w_gamma = cse(gamma_sym / sqrt_w)
constant_laplace_rep = sym.D(LaplaceKernel(dim=2),
inv_sqrt_w_gamma,
qbx_forced_limit=None)
sqrt_w_vec = bind(qbx, sqrt_w)(queue)
def general_mask(test_points):
const_density = bind((qbx, PointsTarget(test_points)),
constant_laplace_rep)(queue,
gamma=sqrt_w_vec).get()
return (abs(const_density) > 0.1)
def inside_domain(test_points):
mask = general_mask(test_points)
return np.array([row[mask] for row in test_points])
def stride_hack(arr):
from numpy.lib.stride_tricks import as_strided
return np.array(as_strided(arr, strides=(8 * len(arr[0]), 8)))
eval_points = inside_domain(eval_points)
eval_points_dev = cl.array.to_device(queue, eval_points)
# Evaluate the solution at the evaluation points
vel = bind((qbx, PointsTarget(eval_points_dev)),
representation_sym)(queue, sigma=sigma, mu=mu, normal=normal)
print("@@@@@@@@")
vel = get_obj_array(vel)
if soln_type == 'fundamental':
exact_soln = fund_soln(eval_points_dev[0], eval_points_dev[1], pt_loc)
else:
exact_soln = couette_soln(eval_points_dev[0], eval_points_dev[1], dp,
h)
err = vel - get_obj_array(exact_soln)
print("@@@@@@@@")
print(
"L2 error estimate: ",
np.sqrt((2. / (nsamp - 1))**2 * np.sum(err[0] * err[0]) +
(2. / (nsamp - 1))**2 * np.sum(err[1] * err[1])))
max_error_loc = [abs(err[0]).argmax(), abs(err[1]).argmax()]
print("max error at sampled points: ", max(abs(err[0])), max(abs(err[1])))
print("exact velocity at max error points: x -> ",
err[0][max_error_loc[0]], ", y -> ", err[1][max_error_loc[1]])
from pytential.symbolic.mappers import DerivativeTaker
rep_pressure = stresslet_obj.apply_pressure(inv_sqrt_w_sigma,
nvec_sym,
mu_sym,
qbx_forced_limit=-2)
pressure = bind((qbx, PointsTarget(eval_points_dev)),
rep_pressure)(queue, sigma=sigma, mu=mu, normal=normal)
pressure = pressure.get()
print "pressure = ", pressure
x_dir_vecs = np.zeros((2, len(eval_points[0])))
x_dir_vecs[0, :] = 1.0
y_dir_vecs = np.zeros((2, len(eval_points[0])))
y_dir_vecs[1, :] = 1.0
x_dir_vecs = cl.array.to_device(queue, x_dir_vecs)
y_dir_vecs = cl.array.to_device(queue, y_dir_vecs)
dir_vec_sym = sym.make_sym_vector("force_direction", dim)
rep_stress = stresslet_obj.apply_stress(inv_sqrt_w_sigma,
nvec_sym,
dir_vec_sym,
mu_sym,
qbx_forced_limit=-2)
applied_stress_x = bind((qbx, PointsTarget(eval_points_dev)),
rep_stress)(queue,
sigma=sigma,
normal=normal,
force_direction=x_dir_vecs,
mu=mu)
applied_stress_x = get_obj_array(applied_stress_x)
applied_stress_y = bind((qbx, PointsTarget(eval_points_dev)),
rep_stress)(queue,
sigma=sigma,
normal=normal,
force_direction=y_dir_vecs,
mu=mu)
applied_stress_y = get_obj_array(applied_stress_y)
print "stress applied to x direction: ", applied_stress_x
print "stress applied to y direction: ", applied_stress_y
import matplotlib.pyplot as plt
plt.quiver(eval_points[0], eval_points[1], vel[0], vel[1], linewidth=0.1)
file_name = "field-n%s.pdf" % (nelements)
plt.savefig(file_name)
return (max(abs(err[0])), max(abs(err[1])))
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
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(places, sym.flat_obj_array(pec_bc_e, pec_bc_h))(
actx, jt=jt, rho=rho, inc_fld=inc_field_scat.field, **knl_kwargs)
def scat_norm(f):
return norm(density_discr, 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))
def run_dielectric_test(cl_ctx, queue, nelements, qbx_order,
op_class, mode,
k0=3, k1=2.9, mesh_order=10,
bdry_quad_order=None, bdry_ovsmp_quad_order=None,
use_l2_weighting=False,
fmm_order=None, visualize=False):
if fmm_order is None:
fmm_order = qbx_order * 2
if bdry_quad_order is None:
bdry_quad_order = mesh_order
if bdry_ovsmp_quad_order is None:
bdry_ovsmp_quad_order = 4*bdry_quad_order
from meshmode.mesh.generation import ellipse, make_curve_mesh
from functools import partial
mesh = make_curve_mesh(
partial(ellipse, 3),
np.linspace(0, 1, nelements+1),
mesh_order)
density_discr = Discretization(
cl_ctx, mesh,
InterpolatoryQuadratureSimplexGroupFactory(bdry_quad_order))
logger.info("%d elements" % mesh.nelements)
# from meshmode.discretization.visualization import make_visualizer
# bdry_vis = make_visualizer(queue, density_discr, 20)
# {{{ solve bvp
from sumpy.kernel import HelmholtzKernel, AxisTargetDerivative
kernel = HelmholtzKernel(2)
beta = 2.5
K0 = np.sqrt(k0**2-beta**2) # noqa
K1 = np.sqrt(k1**2-beta**2) # noqa
pde_op = op_class(
mode,
k_vacuum=1,
interfaces=((0, 1, sym.DEFAULT_SOURCE),),
domain_k_exprs=(k0, k1),
beta=beta,
use_l2_weighting=use_l2_weighting)
op_unknown_sym = pde_op.make_unknown("unknown")
representation0_sym = pde_op.representation(op_unknown_sym, 0)
representation1_sym = pde_op.representation(op_unknown_sym, 1)
from pytential.qbx import QBXLayerPotentialSource
qbx = QBXLayerPotentialSource(
density_discr, fine_order=bdry_ovsmp_quad_order, qbx_order=qbx_order,
fmm_order=fmm_order
).with_refinement()
#print(sym.pretty(pde_op.operator(op_unknown_sym)))
#1/0
bound_pde_op = bind(qbx, pde_op.operator(op_unknown_sym))
e_factor = float(pde_op.ez_enabled)
h_factor = float(pde_op.hz_enabled)
e_sources_0 = make_obj_array(list(np.array([
[0.1, 0.2]
]).T.copy()))
e_strengths_0 = np.array([1*e_factor])
e_sources_1 = make_obj_array(list(np.array([
[4, 4]
]).T.copy()))
e_strengths_1 = np.array([1*e_factor])
h_sources_0 = make_obj_array(list(np.array([
[0.2, 0.1]
]).T.copy()))
h_strengths_0 = np.array([1*h_factor])
h_sources_1 = make_obj_array(list(np.array([
[4, 5]
]).T.copy()))
h_strengths_1 = np.array([1*h_factor])
kernel_grad = [
AxisTargetDerivative(i, kernel) for i in range(density_discr.ambient_dim)]
from sumpy.p2p import P2P
pot_p2p = P2P(cl_ctx, [kernel], exclude_self=False)
pot_p2p_grad = P2P(cl_ctx, kernel_grad, exclude_self=False)
normal = bind(density_discr, sym.normal())(queue).as_vector(np.object)
tangent = bind(
density_discr,
sym.pseudoscalar()/sym.area_element())(queue).as_vector(np.object)
_, (E0,) = pot_p2p(queue, density_discr.nodes(), e_sources_0, [e_strengths_0],
out_host=False, k=K0)
_, (E1,) = pot_p2p(queue, density_discr.nodes(), e_sources_1, [e_strengths_1],
out_host=False, k=K1)
_, (grad0_E0, grad1_E0) = pot_p2p_grad(
queue, density_discr.nodes(), e_sources_0, [e_strengths_0],
out_host=False, k=K0)
_, (grad0_E1, grad1_E1) = pot_p2p_grad(
queue, density_discr.nodes(), e_sources_1, [e_strengths_1],
out_host=False, k=K1)
_, (H0,) = pot_p2p(queue, density_discr.nodes(), h_sources_0, [h_strengths_0],
out_host=False, k=K0)
_, (H1,) = pot_p2p(queue, density_discr.nodes(), h_sources_1, [h_strengths_1],
out_host=False, k=K1)
_, (grad0_H0, grad1_H0) = pot_p2p_grad(
queue, density_discr.nodes(), h_sources_0, [h_strengths_0],
out_host=False, k=K0)
_, (grad0_H1, grad1_H1) = pot_p2p_grad(
queue, density_discr.nodes(), h_sources_1, [h_strengths_1],
out_host=False, k=K1)
E0_dntarget = (grad0_E0*normal[0] + grad1_E0*normal[1]) # noqa
E1_dntarget = (grad0_E1*normal[0] + grad1_E1*normal[1]) # noqa
H0_dntarget = (grad0_H0*normal[0] + grad1_H0*normal[1]) # noqa
H1_dntarget = (grad0_H1*normal[0] + grad1_H1*normal[1]) # noqa
E0_dttarget = (grad0_E0*tangent[0] + grad1_E0*tangent[1]) # noqa
E1_dttarget = (grad0_E1*tangent[0] + grad1_E1*tangent[1]) # noqa
H0_dttarget = (grad0_H0*tangent[0] + grad1_H0*tangent[1]) # noqa
H1_dttarget = (grad0_H1*tangent[0] + grad1_H1*tangent[1]) # noqa
sqrt_w = bind(density_discr, sym.sqrt_jac_q_weight())(queue)
bvp_rhs = np.zeros(len(pde_op.bcs), dtype=np.object)
for i_bc, terms in enumerate(pde_op.bcs):
for term in terms:
assert term.i_interface == 0
if term.field_kind == pde_op.field_kind_e:
if term.direction == pde_op.dir_none:
bvp_rhs[i_bc] += (
term.coeff_outer * E0
+ term.coeff_inner * E1)
elif term.direction == pde_op.dir_normal:
bvp_rhs[i_bc] += (
term.coeff_outer * E0_dntarget
+ term.coeff_inner * E1_dntarget)
elif term.direction == pde_op.dir_tangential:
bvp_rhs[i_bc] += (
term.coeff_outer * E0_dttarget
+ term.coeff_inner * E1_dttarget)
else:
raise NotImplementedError("direction spec in RHS")
elif term.field_kind == pde_op.field_kind_h:
if term.direction == pde_op.dir_none:
bvp_rhs[i_bc] += (
term.coeff_outer * H0
+ term.coeff_inner * H1)
elif term.direction == pde_op.dir_normal:
bvp_rhs[i_bc] += (
term.coeff_outer * H0_dntarget
+ term.coeff_inner * H1_dntarget)
elif term.direction == pde_op.dir_tangential:
bvp_rhs[i_bc] += (
term.coeff_outer * H0_dttarget
+ term.coeff_inner * H1_dttarget)
else:
raise NotImplementedError("direction spec in RHS")
if use_l2_weighting:
bvp_rhs[i_bc] *= sqrt_w
scipy_op = bound_pde_op.scipy_op(queue, "unknown",
domains=[sym.DEFAULT_TARGET]*len(pde_op.bcs), K0=K0, K1=K1,
dtype=np.complex128)
if mode == "tem" or op_class is SRep:
from sumpy.tools import vector_from_device, vector_to_device
from pytential.solve import lu
unknown = lu(scipy_op, vector_from_device(queue, bvp_rhs))
unknown = vector_to_device(queue, unknown)
else:
from pytential.solve import gmres
gmres_result = gmres(scipy_op,
bvp_rhs, tol=1e-14, progress=True,
hard_failure=True, stall_iterations=0)
unknown = gmres_result.solution
# }}}
targets_0 = make_obj_array(list(np.array([
[3.2 + t, -4]
for t in [0, 0.5, 1]
]).T.copy()))
targets_1 = make_obj_array(list(np.array([
[t*-0.3, t*-0.2]
for t in [0, 0.5, 1]
]).T.copy()))
from pytential.target import PointsTarget
from sumpy.tools import vector_from_device
F0_tgt = vector_from_device(queue, bind( # noqa
(qbx, PointsTarget(targets_0)),
representation0_sym)(queue, unknown=unknown, K0=K0, K1=K1))
F1_tgt = vector_from_device(queue, bind( # noqa
(qbx, PointsTarget(targets_1)),
representation1_sym)(queue, unknown=unknown, K0=K0, K1=K1))
_, (E0_tgt_true,) = pot_p2p(queue, targets_0, e_sources_0, [e_strengths_0],
out_host=True, k=K0)
_, (E1_tgt_true,) = pot_p2p(queue, targets_1, e_sources_1, [e_strengths_1],
out_host=True, k=K1)
_, (H0_tgt_true,) = pot_p2p(queue, targets_0, h_sources_0, [h_strengths_0],
out_host=True, k=K0)
_, (H1_tgt_true,) = pot_p2p(queue, targets_1, h_sources_1, [h_strengths_1],
out_host=True, k=K1)
err_F0_total = 0 # noqa
err_F1_total = 0 # noqa
i_field = 0
def vec_norm(ary):
return la.norm(ary.reshape(-1))
def field_kind_to_string(field_kind):
return {pde_op.field_kind_e: "E", pde_op.field_kind_h: "H"}[field_kind]
for field_kind in pde_op.field_kinds:
if not pde_op.is_field_present(field_kind):
continue
if field_kind == pde_op.field_kind_e:
F0_tgt_true = E0_tgt_true # noqa
F1_tgt_true = E1_tgt_true # noqa
elif field_kind == pde_op.field_kind_h:
F0_tgt_true = H0_tgt_true # noqa
F1_tgt_true = H1_tgt_true # noqa
else:
assert False
abs_err_F0 = vec_norm(F0_tgt[i_field] - F0_tgt_true) # noqa
abs_err_F1 = vec_norm(F1_tgt[i_field] - F1_tgt_true) # noqa
rel_err_F0 = abs_err_F0/vec_norm(F0_tgt_true) # noqa
rel_err_F1 = abs_err_F1/vec_norm(F1_tgt_true) # noqa
err_F0_total = max(rel_err_F0, err_F0_total) # noqa
err_F1_total = max(rel_err_F1, err_F1_total) # noqa
print("Abs Err %s0" % field_kind_to_string(field_kind), abs_err_F0)
print("Abs Err %s1" % field_kind_to_string(field_kind), abs_err_F1)
print("Rel Err %s0" % field_kind_to_string(field_kind), rel_err_F0)
print("Rel Err %s1" % field_kind_to_string(field_kind), rel_err_F1)
i_field += 1
if visualize:
from sumpy.visualization import FieldPlotter
fplot = FieldPlotter(np.zeros(2), extent=5, npoints=300)
from pytential.target import PointsTarget
fld0 = bind(
(qbx, PointsTarget(fplot.points)),
representation0_sym)(queue, unknown=unknown, K0=K0)
fld1 = bind(
(qbx, PointsTarget(fplot.points)),
representation1_sym)(queue, unknown=unknown, K1=K1)
comp_fields = []
i_field = 0
for field_kind in pde_op.field_kinds:
if not pde_op.is_field_present(field_kind):
continue
fld_str = field_kind_to_string(field_kind)
comp_fields.extend([
("%s_fld0" % fld_str, fld0[i_field].get()),
("%s_fld1" % fld_str, fld1[i_field].get()),
])
i_field += 0
low_order_qbx = QBXLayerPotentialSource(
density_discr, fine_order=bdry_ovsmp_quad_order, qbx_order=2,
fmm_order=3).with_refinement()
from sumpy.kernel import LaplaceKernel
from pytential.target import PointsTarget
ones = (cl.array.empty(queue, (density_discr.nnodes,), dtype=np.float64)
.fill(1))
ind_func = - bind((low_order_qbx, PointsTarget(fplot.points)),
sym.D(LaplaceKernel(2), sym.var("u")))(
queue, u=ones).get()
_, (e_fld0_true,) = pot_p2p(
queue, fplot.points, e_sources_0, [e_strengths_0],
out_host=True, k=K0)
_, (e_fld1_true,) = pot_p2p(
queue, fplot.points, e_sources_1, [e_strengths_1],
out_host=True, k=K1)
_, (h_fld0_true,) = pot_p2p(
queue, fplot.points, h_sources_0, [h_strengths_0],
out_host=True, k=K0)
_, (h_fld1_true,) = pot_p2p(
queue, fplot.points, h_sources_1, [h_strengths_1],
out_host=True, k=K1)
#fplot.show_scalar_in_mayavi(fld_in_vol.real, max_val=5)
fplot.write_vtk_file(
"potential-n%d.vts" % nelements,
[
("e_fld0_true", e_fld0_true),
("e_fld1_true", e_fld1_true),
("h_fld0_true", h_fld0_true),
("h_fld1_true", h_fld1_true),
("ind", ind_func),
] + comp_fields
)
return err_F0_total, err_F1_total
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),
])
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:]),
])
sym.QBX_SOURCE_QUAD_STAGE2)
logger.info("quad stage-2 elements have %d nodes",
discr.groups[0].nunit_dofs)
# }}}
# {{{ plot geometry
if visualize and ambient_dim == 2:
try:
import matplotlib.pyplot as pt
except ImportError:
visualize = False
if visualize:
normals = bind(places, sym.normal(ambient_dim).as_vector())(actx)
# show geometry, centers, normals
if ambient_dim == 2:
nodes = actx.to_numpy(flatten(density_discr.nodes(),
actx)).reshape(ambient_dim, -1)
normals = actx.to_numpy(flatten(normals,
actx)).reshape(ambient_dim, -1)
pt.plot(nodes[0], nodes[1], "x-")
pt.quiver(nodes[0], nodes[1], normals[0], normals[1])
pt.gca().set_aspect("equal")
pt.savefig(f"pre-solve-source-{resolution}", dpi=300)
elif ambient_dim == 3:
bdry_vis = make_visualizer(actx, density_discr,
case.target_order + 3)
def test_identity_convergence(ctx_getter, case, visualize=False):
logging.basicConfig(level=logging.INFO)
case.check()
cl_ctx = ctx_getter()
queue = cl.CommandQueue(cl_ctx)
# prevent cache 'splosion
from sympy.core.cache import clear_cache
clear_cache()
target_order = 8
from pytools.convergence import EOCRecorder
eoc_rec = EOCRecorder()
for resolution in (
getattr(case, "resolutions", None)
or case.geometry.resolutions
):
mesh = case.geometry.get_mesh(resolution, target_order)
if mesh is None:
break
d = mesh.ambient_dim
k = case.k
lap_k_sym = LaplaceKernel(d)
if k == 0:
k_sym = lap_k_sym
knl_kwargs = {}
else:
k_sym = HelmholtzKernel(d)
knl_kwargs = {"k": sym.var("k")}
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
InterpolatoryQuadratureSimplexGroupFactory
from pytential.qbx import QBXLayerPotentialSource
pre_density_discr = Discretization(
cl_ctx, mesh,
InterpolatoryQuadratureSimplexGroupFactory(target_order))
refiner_extra_kwargs = {}
if case.k != 0:
refiner_extra_kwargs["kernel_length_scale"] = 5/case.k
qbx, _ = QBXLayerPotentialSource(
pre_density_discr, 4*target_order,
case.qbx_order,
fmm_order=case.fmm_order,
fmm_backend=case.fmm_backend,
_expansions_in_tree_have_extent=True,
_expansion_stick_out_factor=getattr(
case, "_expansion_stick_out_factor", 0),
).with_refinement(**refiner_extra_kwargs)
density_discr = qbx.density_discr
# {{{ compute values of a solution to the PDE
nodes_host = density_discr.nodes().get(queue)
normal = bind(density_discr, sym.normal(d))(queue).as_vector(np.object)
normal_host = [normal[j].get() for j in range(d)]
if k != 0:
if d == 2:
angle = 0.3
wave_vec = np.array([np.cos(angle), np.sin(angle)])
u = np.exp(1j*k*np.tensordot(wave_vec, nodes_host, axes=1))
grad_u = 1j*k*wave_vec[:, np.newaxis]*u
elif d == 3:
center = np.array([3, 1, 2])
diff = nodes_host - center[:, np.newaxis]
r = la.norm(diff, axis=0)
u = np.exp(1j*k*r) / r
grad_u = diff * (1j*k*u/r - u/r**2)
else:
raise ValueError("invalid dim")
else:
center = np.array([3, 1, 2])[:d]
diff = nodes_host - center[:, np.newaxis]
dist_squared = np.sum(diff**2, axis=0)
dist = np.sqrt(dist_squared)
if d == 2:
u = np.log(dist)
grad_u = diff/dist_squared
elif d == 3:
u = 1/dist
grad_u = -diff/dist**3
else:
assert False
dn_u = 0
for i in range(d):
dn_u = dn_u + normal_host[i]*grad_u[i]
# }}}
u_dev = cl.array.to_device(queue, u)
dn_u_dev = cl.array.to_device(queue, dn_u)
grad_u_dev = cl.array.to_device(queue, grad_u)
key = (case.qbx_order, case.geometry.mesh_name, resolution,
case.expr.zero_op_name)
bound_op = bind(qbx, case.expr.get_zero_op(k_sym, **knl_kwargs))
error = bound_op(
queue, u=u_dev, dn_u=dn_u_dev, grad_u=grad_u_dev, k=case.k)
if 0:
pt.plot(error)
pt.show()
linf_error_norm = norm(density_discr, queue, error, p=np.inf)
print("--->", key, linf_error_norm)
eoc_rec.add_data_point(qbx.h_max, linf_error_norm)
if visualize:
from meshmode.discretization.visualization import make_visualizer
bdry_vis = make_visualizer(queue, density_discr, target_order)
bdry_normals = bind(density_discr, sym.normal(mesh.ambient_dim))(queue)\
.as_vector(dtype=object)
bdry_vis.write_vtk_file("source-%s.vtu" % resolution, [
("u", u_dev),
("bdry_normals", bdry_normals),
("error", error),
])
print(eoc_rec)
tgt_order = case.qbx_order - case.expr.order_drop
assert eoc_rec.order_estimate() > tgt_order - 1.6
