def test_target_association_failure(ctx_factory):
cl_ctx = ctx_factory()
queue = cl.CommandQueue(cl_ctx)
actx = PyOpenCLArrayContext(queue)
# {{{ generate circle
order = 5
nelements = 40
# Make the curve mesh.
curve_f = partial(ellipse, 1)
mesh = make_curve_mesh(curve_f, np.linspace(0, 1, nelements + 1), order)
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
InterpolatoryQuadratureSimplexGroupFactory
factory = InterpolatoryQuadratureSimplexGroupFactory(order)
discr = Discretization(actx, mesh, factory)
lpot_source = QBXLayerPotentialSource(
discr,
qbx_order=order, # not used in target association
fine_order=order)
places = GeometryCollection(lpot_source)
# }}}
# {{{ generate targets and check
close_circle = 0.999 * np.exp(
2j * np.pi * np.linspace(0, 1, 500, endpoint=False))
from pytential.target import PointsTarget
close_circle_target = (PointsTarget(
actx.from_numpy(np.array([close_circle.real, close_circle.imag]))))
targets = ((close_circle_target, 0), )
from pytential.qbx.target_assoc import (TargetAssociationCodeContainer,
associate_targets_to_qbx_centers,
QBXTargetAssociationFailedException
)
from pytential.qbx.utils import TreeCodeContainer
code_container = TargetAssociationCodeContainer(actx,
TreeCodeContainer(actx))
with pytest.raises(QBXTargetAssociationFailedException):
associate_targets_to_qbx_centers(places,
places.auto_source,
code_container.get_wrangler(actx),
targets,
target_association_tolerance=1e-10)
def make_container():
from pytential.qbx.utils import TreeCodeContainer
return TreeCodeContainer(self._setup_actx)
def tree_code_container(self):
from pytential.qbx.utils import TreeCodeContainer
return TreeCodeContainer(self.cl_context)
def test_target_association(ctx_factory,
curve_name,
curve_f,
nelements,
visualize=False):
cl_ctx = ctx_factory()
queue = cl.CommandQueue(cl_ctx)
actx = PyOpenCLArrayContext(queue)
# {{{ generate lpot source
order = 16
# Make the curve mesh.
mesh = make_curve_mesh(curve_f, np.linspace(0, 1, nelements + 1), order)
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
InterpolatoryQuadratureSimplexGroupFactory
factory = InterpolatoryQuadratureSimplexGroupFactory(order)
discr = Discretization(actx, mesh, factory)
lpot_source = QBXLayerPotentialSource(
discr,
qbx_order=order, # not used in target association
fine_order=order)
places = GeometryCollection(lpot_source)
# }}}
# {{{ generate targets
from pyopencl.clrandom import PhiloxGenerator
rng = PhiloxGenerator(cl_ctx, seed=RNG_SEED)
dd = places.auto_source.to_stage1()
centers = dof_array_to_numpy(
actx,
bind(
places,
sym.interleaved_expansion_centers(lpot_source.ambient_dim,
dofdesc=dd))(actx))
density_discr = places.get_discretization(dd.geometry)
noise = actx.to_numpy(
rng.uniform(queue, density_discr.ndofs, dtype=np.float, a=0.01, b=1.0))
tunnel_radius = dof_array_to_numpy(
actx,
bind(
places,
sym._close_target_tunnel_radii(lpot_source.ambient_dim,
dofdesc=dd))(actx))
def targets_from_sources(sign, dist, dim=2):
nodes = dof_array_to_numpy(
actx,
bind(places, sym.nodes(dim,
dofdesc=dd))(actx).as_vector(np.object))
normals = dof_array_to_numpy(
actx,
bind(places, sym.normal(dim,
dofdesc=dd))(actx).as_vector(np.object))
return actx.from_numpy(nodes + normals * sign * dist)
from pytential.target import PointsTarget
int_targets = PointsTarget(targets_from_sources(-1, noise * tunnel_radius))
ext_targets = PointsTarget(targets_from_sources(+1, noise * tunnel_radius))
far_targets = PointsTarget(
targets_from_sources(+1, FAR_TARGET_DIST_FROM_SOURCE))
# Create target discretizations.
target_discrs = (
# On-surface targets, interior
(density_discr, -1),
# On-surface targets, exterior
(density_discr, +1),
# Interior close targets
(int_targets, -2),
# Exterior close targets
(ext_targets, +2),
# Far targets, should not need centers
(far_targets, 0),
)
sizes = np.cumsum([discr.ndofs for discr, _ in target_discrs])
(
surf_int_slice,
surf_ext_slice,
vol_int_slice,
vol_ext_slice,
far_slice,
) = [slice(start, end) for start, end in zip(np.r_[0, sizes], sizes)]
# }}}
# {{{ run target associator and check
from pytential.qbx.target_assoc import (TargetAssociationCodeContainer,
associate_targets_to_qbx_centers)
from pytential.qbx.utils import TreeCodeContainer
code_container = TargetAssociationCodeContainer(actx,
TreeCodeContainer(actx))
target_assoc = (associate_targets_to_qbx_centers(
places,
places.auto_source,
code_container.get_wrangler(actx),
target_discrs,
target_association_tolerance=1e-10).get(queue=queue))
expansion_radii = dof_array_to_numpy(
actx,
bind(
places,
sym.expansion_radii(lpot_source.ambient_dim,
granularity=sym.GRANULARITY_CENTER))(actx))
from meshmode.dof_array import thaw
surf_targets = dof_array_to_numpy(actx, thaw(actx, density_discr.nodes()))
int_targets = actx.to_numpy(int_targets.nodes())
ext_targets = actx.to_numpy(ext_targets.nodes())
def visualize_curve_and_assoc():
import matplotlib.pyplot as plt
from meshmode.mesh.visualization import draw_curve
draw_curve(density_discr.mesh)
targets = int_targets
tgt_slice = surf_int_slice
plt.plot(centers[0], centers[1], "+", color="orange")
ax = plt.gca()
for tx, ty, tcenter in zip(targets[0, tgt_slice], targets[1,
tgt_slice],
target_assoc.target_to_center[tgt_slice]):
if tcenter >= 0:
ax.add_artist(
plt.Line2D(
(tx, centers[0, tcenter]),
(ty, centers[1, tcenter]),
))
ax.set_aspect("equal")
plt.show()
if visualize:
visualize_curve_and_assoc()
# Checks that the targets match with centers on the appropriate side and
# within the allowable distance.
def check_close_targets(centers, targets, true_side, target_to_center,
target_to_side_result, tgt_slice):
targets_have_centers = (target_to_center >= 0).all()
assert targets_have_centers
assert (target_to_side_result == true_side).all()
TOL = 1e-3
dists = la.norm((targets.T - centers.T[target_to_center]), axis=1)
assert (dists <= (1 + TOL) * expansion_radii[target_to_center]).all()
# Center side order = -1, 1, -1, 1, ...
target_to_center_side = 2 * (target_assoc.target_to_center % 2) - 1
# interior surface
check_close_targets(centers, surf_targets, -1,
target_assoc.target_to_center[surf_int_slice],
target_to_center_side[surf_int_slice], surf_int_slice)
# exterior surface
check_close_targets(centers, surf_targets, +1,
target_assoc.target_to_center[surf_ext_slice],
target_to_center_side[surf_ext_slice], surf_ext_slice)
# interior volume
check_close_targets(centers, int_targets, -1,
target_assoc.target_to_center[vol_int_slice],
target_to_center_side[vol_int_slice], vol_int_slice)
# exterior volume
check_close_targets(centers, ext_targets, +1,
target_assoc.target_to_center[vol_ext_slice],
target_to_center_side[vol_ext_slice], vol_ext_slice)
# Checks that far targets are not assigned a center.
assert (target_assoc.target_to_center[far_slice] == -1).all()
def run_source_refinement_test(ctx_factory, mesh, order, helmholtz_k=None):
cl_ctx = ctx_factory()
queue = cl.CommandQueue(cl_ctx)
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import (
InterpolatoryQuadratureSimplexGroupFactory)
factory = InterpolatoryQuadratureSimplexGroupFactory(order)
discr = Discretization(cl_ctx, mesh, factory)
from pytential.qbx.refinement import (RefinerCodeContainer,
refine_for_global_qbx)
from pytential.qbx.utils import TreeCodeContainer
lpot_source = QBXLayerPotentialSource(
discr,
qbx_order=order, # not used in refinement
fine_order=order)
del discr
expansion_disturbance_tolerance = 0.025
refiner_extra_kwargs = {
"expansion_disturbance_tolerance": expansion_disturbance_tolerance,
}
if helmholtz_k is not None:
refiner_extra_kwargs["kernel_length_scale"] = 5 / helmholtz_k
lpot_source, conn = refine_for_global_qbx(
lpot_source,
RefinerCodeContainer(cl_ctx,
TreeCodeContainer(cl_ctx)).get_wrangler(queue),
factory, **refiner_extra_kwargs)
discr_nodes = lpot_source.density_discr.nodes().get(queue)
fine_discr_nodes = \
lpot_source.quad_stage2_density_discr.nodes().get(queue)
int_centers = bind(lpot_source,
sym.expansion_centers(lpot_source.ambient_dim,
-1))(queue)
int_centers = np.array([axis.get(queue) for axis in int_centers])
ext_centers = bind(lpot_source,
sym.expansion_centers(lpot_source.ambient_dim,
+1))(queue)
ext_centers = np.array([axis.get(queue) for axis in ext_centers])
expansion_radii = bind(lpot_source,
sym.expansion_radii(
lpot_source.ambient_dim))(queue).get()
source_danger_zone_radii = bind(
lpot_source,
sym._source_danger_zone_radii(
lpot_source.ambient_dim,
dofdesc=sym.GRANULARITY_ELEMENT))(queue).get()
quad_res = bind(
lpot_source,
sym._quad_resolution(lpot_source.ambient_dim,
dofdesc=sym.GRANULARITY_ELEMENT))(queue)
# {{{ check if satisfying criteria
def check_disk_undisturbed_by_sources(centers_panel, sources_panel):
if centers_panel.element_nr == sources_panel.element_nr:
# Same panel
return
my_int_centers = int_centers[:, centers_panel.discr_slice]
my_ext_centers = ext_centers[:, centers_panel.discr_slice]
all_centers = np.append(my_int_centers, my_ext_centers, axis=-1)
nodes = discr_nodes[:, sources_panel.discr_slice]
# =distance(centers of panel 1, panel 2)
dist = (la.norm(
(all_centers[..., np.newaxis] - nodes[:, np.newaxis, ...]).T,
axis=-1).min())
# Criterion:
# A center cannot be closer to another panel than to its originating
# panel.
rad = expansion_radii[centers_panel.discr_slice]
assert (dist >= rad * (1-expansion_disturbance_tolerance)).all(), \
(dist, rad, centers_panel.element_nr, sources_panel.element_nr)
def check_sufficient_quadrature_resolution(centers_panel, sources_panel):
dz_radius = source_danger_zone_radii[sources_panel.element_nr]
my_int_centers = int_centers[:, centers_panel.discr_slice]
my_ext_centers = ext_centers[:, centers_panel.discr_slice]
all_centers = np.append(my_int_centers, my_ext_centers, axis=-1)
nodes = fine_discr_nodes[:, sources_panel.discr_slice]
# =distance(centers of panel 1, panel 2)
dist = (la.norm(
(all_centers[..., np.newaxis] - nodes[:, np.newaxis, ...]).T,
axis=-1).min())
# Criterion:
# The quadrature contribution from each panel is as accurate
# as from the center's own source panel.
assert dist >= dz_radius, \
(dist, dz_radius, centers_panel.element_nr, sources_panel.element_nr)
def check_quad_res_to_helmholtz_k_ratio(panel):
# Check wavenumber to panel size ratio.
assert quad_res[panel.element_nr] * helmholtz_k <= 5
for i, panel_1 in enumerate(iter_elements(lpot_source.density_discr)):
for panel_2 in iter_elements(lpot_source.density_discr):
check_disk_undisturbed_by_sources(panel_1, panel_2)
for panel_2 in iter_elements(lpot_source.quad_stage2_density_discr):
check_sufficient_quadrature_resolution(panel_1, panel_2)
if helmholtz_k is not None:
check_quad_res_to_helmholtz_k_ratio(panel_1)