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 test_target_association_failure(ctx_getter):
cl_ctx = ctx_getter()
queue = cl.CommandQueue(cl_ctx)
# {{{ 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(cl_ctx, mesh, factory)
lpot_source = QBXLayerPotentialSource(discr,
qbx_order=order, # not used in target association
fine_order=order)
# }}}
# {{{ 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(cl.array.to_device(
queue, 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(
cl_ctx, TreeCodeContainer(cl_ctx))
with pytest.raises(QBXTargetAssociationFailedException):
associate_targets_to_qbx_centers(
lpot_source,
code_container.get_wrangler(queue),
targets,
target_association_tolerance=1e-10)
def _get_centers_and_expansion_radii(queue, source, target_discr,
qbx_forced_limit):
"""
:arg queue: a :class:`pyopencl.CommandQueue`.
:arg source: a :class:`pytential.source.LayerPotentialSourceBase`.
:arg target_discr: a :class:`meshmode.discretization.Discretization`.
:arg qbx_forced_limit: an integer (*+1* or *-1*).
:return: a tuple of `(centers, radii)` for each node in *target_discr*.
"""
if source.density_discr is target_discr:
# NOTE: skip expensive target association
centers = bind(
source, sym.expansion_centers(source.ambient_dim,
qbx_forced_limit))(queue)
radii = bind(source, sym.expansion_radii(source.ambient_dim))(queue)
else:
from pytential.qbx.utils import get_interleaved_centers
centers = get_interleaved_centers(queue, source)
radii = bind(
source,
sym.expansion_radii(source.ambient_dim,
granularity=sym.GRANULARITY_CENTER))(queue)
# NOTE: using a very small tolerance to make sure all the stage2
# targets are associated to a center. We can't use the user provided
# source.target_association_tolerance here because it will likely be
# way too small.
target_association_tolerance = 1.0e-1
from pytential.qbx.target_assoc import associate_targets_to_qbx_centers
code_container = source.target_association_code_container
assoc = associate_targets_to_qbx_centers(
source,
code_container.get_wrangler(queue),
[(target_discr, qbx_forced_limit)],
target_association_tolerance=target_association_tolerance)
centers = [
cl.array.take(c, assoc.target_to_center, queue=queue)
for c in centers
]
radii = cl.array.take(radii, assoc.target_to_center, queue=queue)
return centers, radii
def user_target_to_center(self):
"""Find which QBX center, if any, is to be used for each target.
:attr:`target_state.NO_QBX_NEEDED` if none. :attr:`target_state.FAILED`
if a center needs to be used, but none was found.
See :meth:`center_to_tree_targets` for the reverse look-up table.
Shape: ``[ntargets]`` of :attr:`boxtree.Tree.particle_id_dtype`, with extra
values from :class:`target_state` allowed. Targets occur in user order.
"""
from pytential.qbx.target_assoc import associate_targets_to_qbx_centers
target_info = self.target_info()
from pytential.target import PointsTarget
queue = self.array_context.queue
target_side_prefs = (
self.target_side_preferences()[self.ncenters:].get(queue=queue))
target_discrs_and_qbx_sides = [
(PointsTarget(target_info.targets[:, self.ncenters:]),
target_side_prefs.astype(np.int32))
]
target_association_wrangler = (
self.lpot_source.target_association_code_container.get_wrangler(
self.array_context))
tgt_assoc_result = associate_targets_to_qbx_centers(
self.places,
self.source_dd,
target_association_wrangler,
target_discrs_and_qbx_sides,
target_association_tolerance=(self.target_association_tolerance),
debug=self.debug)
result = cl.array.empty(queue, target_info.ntargets,
tgt_assoc_result.target_to_center.dtype)
result[:self.ncenters].fill(target_state.NO_QBX_NEEDED)
result[self.ncenters:] = tgt_assoc_result.target_to_center
return result.with_queue(None)
def user_target_to_center(self):
"""Find which QBX center, if any, is to be used for each target.
:attr:`target_state.NO_QBX_NEEDED` if none. :attr:`target_state.FAILED`
if a center needs to be used, but none was found.
See :meth:`center_to_tree_targets` for the reverse look-up table.
Shape: ``[ntargets]`` of :attr:`boxtree.Tree.particle_id_dtype`, with extra
values from :class:`target_state` allowed. Targets occur in user order.
"""
from pytential.qbx.target_assoc import associate_targets_to_qbx_centers
tgt_info = self.target_info()
from pytential.target import PointsTarget
with cl.CommandQueue(self.cl_context) as queue:
target_side_prefs = (self
.target_side_preferences()[self.ncenters:].get(queue=queue))
target_discrs_and_qbx_sides = [(
PointsTarget(tgt_info.targets[:, self.ncenters:]),
target_side_prefs.astype(np.int32))]
target_association_wrangler = (
self.lpot_source.target_association_code_container
.get_wrangler(queue))
tgt_assoc_result = associate_targets_to_qbx_centers(
self.lpot_source,
target_association_wrangler,
target_discrs_and_qbx_sides,
target_association_tolerance=(
self.target_association_tolerance))
result = cl.array.empty(queue, tgt_info.ntargets,
tgt_assoc_result.target_to_center.dtype)
result[:self.ncenters].fill(target_state.NO_QBX_NEEDED)
result[self.ncenters:] = tgt_assoc_result.target_to_center
return result.with_queue(None)
def _get_centers_and_expansion_radii(queue, source, target_discr, qbx_forced_limit):
"""
:arg queue: a :class:`pyopencl.CommandQueue`.
:arg source: a :class:`pytential.source.LayerPotentialSourceBase`.
:arg target_discr: a :class:`meshmode.discretization.Discretization`.
:arg qbx_forced_limit: an integer (*+1* or *-1*).
:return: a tuple of `(centers, radii)` for each node in *target_discr*.
"""
if source.density_discr is target_discr:
# NOTE: skip expensive target association
from pytential.qbx.utils import get_centers_on_side
centers = get_centers_on_side(source, qbx_forced_limit)
radii = source._expansion_radii('nsources')
else:
from pytential.qbx.utils import get_interleaved_centers
centers = get_interleaved_centers(queue, source)
radii = source._expansion_radii('ncenters')
# NOTE: using a very small tolerance to make sure all the stage2
# targets are associated to a center. We can't use the user provided
# source.target_association_tolerance here because it will likely be
# way too small.
target_association_tolerance = 1.0e-1
from pytential.qbx.target_assoc import associate_targets_to_qbx_centers
code_container = source.target_association_code_container
assoc = associate_targets_to_qbx_centers(
source,
code_container.get_wrangler(queue),
[(target_discr, qbx_forced_limit)],
target_association_tolerance=target_association_tolerance)
centers = [cl.array.take(c, assoc.target_to_center, queue=queue)
for c in centers]
radii = cl.array.take(radii, assoc.target_to_center, queue=queue)
return centers, radii
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 test_target_association(ctx_getter, curve_name, curve_f, nelements,
visualize=False):
cl_ctx = ctx_getter()
queue = cl.CommandQueue(cl_ctx)
# {{{ 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(cl_ctx, mesh, factory)
lpot_source, conn = QBXLayerPotentialSource(discr,
qbx_order=order, # not used in target association
fine_order=order).with_refinement()
del discr
from pytential.qbx.utils import get_interleaved_centers
centers = np.array([ax.get(queue)
for ax in get_interleaved_centers(queue, lpot_source)])
# }}}
# {{{ generate targets
from pyopencl.clrandom import PhiloxGenerator
rng = PhiloxGenerator(cl_ctx, seed=RNG_SEED)
nsources = lpot_source.density_discr.nnodes
noise = rng.uniform(queue, nsources, dtype=np.float, a=0.01, b=1.0)
tunnel_radius = \
lpot_source._close_target_tunnel_radius("nsources").with_queue(queue)
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)
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
(lpot_source.density_discr, -1),
# On-surface targets, exterior
(lpot_source.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.nnodes 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(
cl_ctx, TreeCodeContainer(cl_ctx))
target_assoc = (associate_targets_to_qbx_centers(
lpot_source,
code_container.get_wrangler(queue),
target_discrs,
target_association_tolerance=1e-10)
.get(queue=queue))
expansion_radii = lpot_source._expansion_radii("ncenters").get(queue)
surf_targets = np.array(
[axis.get(queue) for axis in lpot_source.density_discr.nodes()])
int_targets = np.array([axis.get(queue) for axis in int_targets.nodes()])
ext_targets = np.array([axis.get(queue) for axis in ext_targets.nodes()])
def visualize_curve_and_assoc():
import matplotlib.pyplot as plt
from meshmode.mesh.visualization import draw_curve
draw_curve(lpot_source.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()