def lu(op, rhs, show_spectrum=False):
import numpy.linalg as la
from sumpy.tools import build_matrix
mat = build_matrix(op)
print("condition number: %g" % la.cond(mat))
if show_spectrum:
ev = la.eigvals(mat)
import matplotlib.pyplot as pt
pt.plot(ev.real, ev.imag, "o")
pt.show()
return la.solve(mat, rhs)
def lu(op, rhs, show_spectrum=False):
import numpy.linalg as la
from sumpy.tools import build_matrix
mat = build_matrix(op)
print("condition number: %g" % la.cond(mat))
if show_spectrum:
ev = la.eigvals(mat)
import matplotlib.pyplot as pt
pt.plot(ev.real, ev.imag, "o")
pt.show()
chopper = VectorChopper(rhs)
return chopper.chop(
la.solve(mat,
chopper.stack(rhs)))
def main(curve_fn=starfish, visualize=True):
import logging
logging.basicConfig(level=logging.WARNING) # INFO for more progress info
import pyopencl as cl
cl_ctx = cl.create_some_context()
queue = cl.CommandQueue(cl_ctx)
actx = PyOpenCLArrayContext(queue, force_device_scalars=True)
from meshmode.mesh.generation import make_curve_mesh
mesh = make_curve_mesh(
curve_fn,
np.linspace(0, 1, nelements+1),
target_order)
from pytential.qbx import QBXLayerPotentialSource
from meshmode.discretization import Discretization
from meshmode.discretization.poly_element import \
InterpolatoryQuadratureSimplexGroupFactory
pre_density_discr = Discretization(
actx, mesh, InterpolatoryQuadratureSimplexGroupFactory(target_order))
qbx = QBXLayerPotentialSource(
pre_density_discr, 4*target_order, qbx_order,
fmm_order=qbx_order+3,
target_association_tolerance=0.005,
#fmm_backend="fmmlib",
)
from pytential.target import PointsTarget
fplot = FieldPlotter(np.zeros(2), extent=5, npoints=1000)
targets_dev = actx.from_numpy(fplot.points)
from pytential import GeometryCollection
places = GeometryCollection({
"qbx": qbx,
"targets": PointsTarget(targets_dev),
}, auto_where="qbx")
density_discr = places.get_discretization("qbx")
nodes = thaw(density_discr.nodes(), actx)
angle = actx.np.arctan2(nodes[1], nodes[0])
if k:
kernel = HelmholtzKernel(2)
kernel_kwargs = {"k": sym.var("k")}
else:
kernel = LaplaceKernel(2)
kernel_kwargs = {}
def op(**kwargs):
kwargs.update(kernel_kwargs)
#op = sym.d_dx(sym.S(kernel, sym.var("sigma"), **kwargs))
return sym.D(kernel, sym.var("sigma"), **kwargs)
#op = sym.S(kernel, sym.var("sigma"), qbx_forced_limit=None, **kwargs)
if 0:
from random import randrange
sigma = actx.zeros(density_discr.ndofs, angle.entry_dtype)
for _ in range(5):
sigma[randrange(len(sigma))] = 1
from arraycontext import unflatten
sigma = unflatten(angle, sigma, actx)
else:
sigma = actx.np.cos(mode_nr*angle)
if isinstance(kernel, HelmholtzKernel):
for i, elem in np.ndenumerate(sigma):
sigma[i] = elem.astype(np.complex128)
bound_bdry_op = bind(places, op())
if visualize:
fld_in_vol = actx.to_numpy(
bind(places, op(
source="qbx",
target="targets",
qbx_forced_limit=None))(actx, sigma=sigma, k=k))
if enable_mayavi:
fplot.show_scalar_in_mayavi(fld_in_vol.real, max_val=5)
else:
fplot.write_vtk_file("layerpot-potential.vts", [
("potential", fld_in_vol)
])
if 0:
apply_op = bound_bdry_op.scipy_op(actx, "sigma", np.float64, k=k)
from sumpy.tools import build_matrix
mat = build_matrix(apply_op)
import matplotlib.pyplot as pt
pt.imshow(mat)
pt.colorbar()
pt.show()
if enable_mayavi:
# {{{ plot boundary field
from arraycontext import flatten
fld_on_bdry = actx.to_numpy(
flatten(bound_bdry_op(actx, sigma=sigma, k=k), actx))
nodes_host = actx.to_numpy(
flatten(density_discr.nodes(), actx)
).reshape(density_discr.ambient_dim, -1)
mlab.points3d(nodes_host[0], nodes_host[1],
fld_on_bdry.real, scale_factor=0.03)
mlab.colorbar()
mlab.show()
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)
np.linspace(0, 1, nelements+1),
target_order)
from pytential.discretization.qbx import make_upsampling_qbx_discr
discr = make_upsampling_qbx_discr(
cl_ctx, mesh, target_order, qbx_order)
nodes = discr.nodes().with_queue(queue)
angle = cl.clmath.atan2(nodes[1], nodes[0])
from pytential import bind, sym
representation = sym.S(0, sym.var("sigma"))
op = representation
bc = cl.clmath.cos(mode_nr*angle)
bound_op = bind(discr, op)
from sumpy.tools import build_matrix
mat = build_matrix(bound_op.scipy_op(queue, "sigma"))
w, v = la.eig(mat)
import matplotlib.pyplot as pt
pt.plot(w.real, w.imag, "x")
pt.rc("font", size=20)
pt.grid()
pt.show()
def draw_pot_figure(aspect_ratio,
nsrc=100,
novsmp=None,
helmholtz_k=0,
what_operator="S",
what_operator_lpot=None,
order=4,
ovsmp_center_exp=0.66,
force_center_side=None):
import logging
logging.basicConfig(level=logging.INFO)
if novsmp is None:
novsmp = 4 * nsrc
if what_operator_lpot is None:
what_operator_lpot = what_operator
ctx = cl.create_some_context()
queue = cl.CommandQueue(ctx)
# {{{ make plot targets
center = np.asarray([0, 0], dtype=np.float64)
from sumpy.visualization import FieldPlotter
fp = FieldPlotter(center, npoints=1000, extent=6)
# }}}
# {{{ make p2p kernel calculator
from sumpy.p2p import P2P
from sumpy.kernel import LaplaceKernel, HelmholtzKernel
from sumpy.expansion.local import H2DLocalExpansion, LineTaylorLocalExpansion
if helmholtz_k:
if isinstance(helmholtz_k, complex):
knl = HelmholtzKernel(2, allow_evanescent=True)
expn_class = H2DLocalExpansion
knl_kwargs = {"k": helmholtz_k}
else:
knl = HelmholtzKernel(2)
expn_class = H2DLocalExpansion
knl_kwargs = {"k": helmholtz_k}
else:
knl = LaplaceKernel(2)
expn_class = LineTaylorLocalExpansion
knl_kwargs = {}
vol_knl = process_kernel(knl, what_operator)
p2p = P2P(ctx, [vol_knl], exclude_self=False, value_dtypes=np.complex128)
lpot_knl = process_kernel(knl, what_operator_lpot)
from sumpy.qbx import LayerPotential
lpot = LayerPotential(ctx, [expn_class(lpot_knl, order=order)],
value_dtypes=np.complex128)
# }}}
# {{{ set up geometry
# r,a,b match the corresponding letters from G. J. Rodin and O. Steinbach,
# Boundary Element Preconditioners for problems defined on slender domains.
# http://dx.doi.org/10.1137/S1064827500372067
a = 1
b = 1 / aspect_ratio
def map_to_curve(t):
t = t * (2 * np.pi)
x = a * np.cos(t)
y = b * np.sin(t)
w = (np.zeros_like(t) + 1) / len(t)
return x, y, w
from curve import CurveGrid
native_t = np.linspace(0, 1, nsrc, endpoint=False)
native_x, native_y, native_weights = map_to_curve(native_t)
native_curve = CurveGrid(native_x, native_y)
ovsmp_t = np.linspace(0, 1, novsmp, endpoint=False)
ovsmp_x, ovsmp_y, ovsmp_weights = map_to_curve(ovsmp_t)
ovsmp_curve = CurveGrid(ovsmp_x, ovsmp_y)
curve_len = np.sum(ovsmp_weights * ovsmp_curve.speed)
hovsmp = curve_len / novsmp
center_dist = 5 * hovsmp
if force_center_side is not None:
center_side = force_center_side * np.ones(len(native_curve))
else:
center_side = -np.sign(native_curve.mean_curvature)
centers = (native_curve.pos +
center_side[:, np.newaxis] * center_dist * native_curve.normal)
#native_curve.plot()
#pt.show()
volpot_kwargs = knl_kwargs.copy()
lpot_kwargs = knl_kwargs.copy()
if what_operator == "D":
volpot_kwargs["src_derivative_dir"] = native_curve.normal
if what_operator_lpot == "D":
lpot_kwargs["src_derivative_dir"] = ovsmp_curve.normal
if what_operator_lpot == "S'":
lpot_kwargs["tgt_derivative_dir"] = native_curve.normal
# }}}
if 0:
# {{{ build matrix
from fourier import make_fourier_interp_matrix
fim = make_fourier_interp_matrix(novsmp, nsrc)
from sumpy.tools import build_matrix
from scipy.sparse.linalg import LinearOperator
def apply_lpot(x):
xovsmp = np.dot(fim, x)
evt, (y, ) = lpot(queue,
native_curve.pos,
ovsmp_curve.pos,
centers,
[xovsmp * ovsmp_curve.speed * ovsmp_weights],
expansion_radii=np.ones(centers.shape[1]),
**lpot_kwargs)
return y
op = LinearOperator((nsrc, nsrc), apply_lpot)
mat = build_matrix(op, dtype=np.complex128)
w, v = la.eig(mat)
pt.plot(w.real, "o-")
#import sys; sys.exit(0)
return
# }}}
# {{{ compute potentials
mode_nr = 0
density = np.cos(mode_nr * 2 * np.pi * native_t).astype(np.complex128)
ovsmp_density = np.cos(mode_nr * 2 * np.pi * ovsmp_t).astype(np.complex128)
evt, (vol_pot, ) = p2p(queue, fp.points, native_curve.pos,
[native_curve.speed * native_weights * density],
**volpot_kwargs)
evt, (curve_pot, ) = lpot(
queue,
native_curve.pos,
ovsmp_curve.pos,
centers, [ovsmp_density * ovsmp_curve.speed * ovsmp_weights],
expansion_radii=np.ones(centers.shape[1]),
**lpot_kwargs)
# }}}
if 0:
# {{{ plot on-surface potential in 2D
pt.plot(curve_pot, label="pot")
pt.plot(density, label="dens")
pt.legend()
pt.show()
# }}}
fp.write_vtk_file("potential.vts", [("potential", vol_pot.real)])
if 0:
# {{{ 2D false-color plot
pt.clf()
plotval = np.log10(1e-20 + np.abs(vol_pot))
im = fp.show_scalar_in_matplotlib(plotval.real)
from matplotlib.colors import Normalize
im.set_norm(Normalize(vmin=-2, vmax=1))
src = native_curve.pos
pt.plot(src[:, 0], src[:, 1], "o-k")
# close the curve
pt.plot(src[-1::-len(src) + 1, 0], src[-1::-len(src) + 1, 1], "o-k")
#pt.gca().set_aspect("equal", "datalim")
cb = pt.colorbar(shrink=0.9)
cb.set_label(r"$\log_{10}(\mathdefault{Error})$")
#from matplotlib.ticker import NullFormatter
#pt.gca().xaxis.set_major_formatter(NullFormatter())
#pt.gca().yaxis.set_major_formatter(NullFormatter())
fp.set_matplotlib_limits()
# }}}
else:
# {{{ 3D plots
plotval_vol = vol_pot.real
plotval_c = curve_pot.real
scale = 1
if 0:
# crop singularities--doesn't work very well
neighbors = [
np.roll(plotval_vol, 3, 0),
np.roll(plotval_vol, -3, 0),
np.roll(plotval_vol, 6, 0),
np.roll(plotval_vol, -6, 0),
]
avg = np.average(np.abs(plotval_vol))
outlier_flag = sum(np.abs(plotval_vol - nb)
for nb in neighbors) > avg
plotval_vol[outlier_flag] = sum(
nb[outlier_flag] for nb in neighbors) / len(neighbors)
fp.show_scalar_in_mayavi(scale * plotval_vol, max_val=1)
from mayavi import mlab
mlab.colorbar()
if 1:
mlab.points3d(native_curve.pos[0],
native_curve.pos[1],
scale * plotval_c,
scale_factor=0.02)
mlab.show()
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 draw_pot_figure(aspect_ratio,
nsrc=100, novsmp=None, helmholtz_k=0,
what_operator="S",
what_operator_lpot=None,
order=4,
ovsmp_center_exp=0.66,
force_center_side=None):
import logging
logging.basicConfig(level=logging.INFO)
if novsmp is None:
novsmp = 4*nsrc
if what_operator_lpot is None:
what_operator_lpot = what_operator
ctx = cl.create_some_context()
queue = cl.CommandQueue(ctx)
# {{{ make plot targets
center = np.asarray([0, 0], dtype=np.float64)
from sumpy.visualization import FieldPlotter
fp = FieldPlotter(center, npoints=1000, extent=6)
# }}}
# {{{ make p2p kernel calculator
from sumpy.p2p import P2P
from sumpy.kernel import LaplaceKernel, HelmholtzKernel
from sumpy.expansion.local import H2DLocalExpansion, LineTaylorLocalExpansion
if helmholtz_k:
if isinstance(helmholtz_k, complex):
knl = HelmholtzKernel(2, allow_evanescent=True)
expn_class = H2DLocalExpansion
knl_kwargs = {"k": helmholtz_k}
else:
knl = HelmholtzKernel(2)
expn_class = H2DLocalExpansion
knl_kwargs = {"k": helmholtz_k}
else:
knl = LaplaceKernel(2)
expn_class = LineTaylorLocalExpansion
knl_kwargs = {}
vol_knl = process_kernel(knl, what_operator)
p2p = P2P(ctx, [vol_knl], exclude_self=False,
value_dtypes=np.complex128)
lpot_knl = process_kernel(knl, what_operator_lpot)
from sumpy.qbx import LayerPotential
lpot = LayerPotential(ctx, [
expn_class(lpot_knl, order=order)],
value_dtypes=np.complex128)
# }}}
# {{{ set up geometry
# r,a,b match the corresponding letters from G. J. Rodin and O. Steinbach,
# Boundary Element Preconditioners for problems defined on slender domains.
# http://dx.doi.org/10.1137/S1064827500372067
a = 1
b = 1/aspect_ratio
def map_to_curve(t):
t = t*(2*np.pi)
x = a*np.cos(t)
y = b*np.sin(t)
w = (np.zeros_like(t)+1)/len(t)
return x, y, w
from curve import CurveGrid
native_t = np.linspace(0, 1, nsrc, endpoint=False)
native_x, native_y, native_weights = map_to_curve(native_t)
native_curve = CurveGrid(native_x, native_y)
ovsmp_t = np.linspace(0, 1, novsmp, endpoint=False)
ovsmp_x, ovsmp_y, ovsmp_weights = map_to_curve(ovsmp_t)
ovsmp_curve = CurveGrid(ovsmp_x, ovsmp_y)
curve_len = np.sum(ovsmp_weights * ovsmp_curve.speed)
hovsmp = curve_len/novsmp
center_dist = 5*hovsmp
if force_center_side is not None:
center_side = force_center_side*np.ones(len(native_curve))
else:
center_side = -np.sign(native_curve.mean_curvature)
centers = (native_curve.pos
+ center_side[:, np.newaxis]
* center_dist*native_curve.normal)
#native_curve.plot()
#pt.show()
volpot_kwargs = knl_kwargs.copy()
lpot_kwargs = knl_kwargs.copy()
if what_operator == "D":
volpot_kwargs["src_derivative_dir"] = native_curve.normal
if what_operator_lpot == "D":
lpot_kwargs["src_derivative_dir"] = ovsmp_curve.normal
if what_operator_lpot == "S'":
lpot_kwargs["tgt_derivative_dir"] = native_curve.normal
# }}}
if 0:
# {{{ build matrix
from fourier import make_fourier_interp_matrix
fim = make_fourier_interp_matrix(novsmp, nsrc)
from sumpy.tools import build_matrix
from scipy.sparse.linalg import LinearOperator
def apply_lpot(x):
xovsmp = np.dot(fim, x)
evt, (y,) = lpot(queue, native_curve.pos, ovsmp_curve.pos,
centers,
[xovsmp * ovsmp_curve.speed * ovsmp_weights],
expansion_radii=np.ones(centers.shape[1]),
**lpot_kwargs)
return y
op = LinearOperator((nsrc, nsrc), apply_lpot)
mat = build_matrix(op, dtype=np.complex128)
w, v = la.eig(mat)
pt.plot(w.real, "o-")
#import sys; sys.exit(0)
return
# }}}
# {{{ compute potentials
mode_nr = 0
density = np.cos(mode_nr*2*np.pi*native_t).astype(np.complex128)
ovsmp_density = np.cos(mode_nr*2*np.pi*ovsmp_t).astype(np.complex128)
evt, (vol_pot,) = p2p(queue, fp.points, native_curve.pos,
[native_curve.speed*native_weights*density], **volpot_kwargs)
evt, (curve_pot,) = lpot(queue, native_curve.pos, ovsmp_curve.pos,
centers,
[ovsmp_density * ovsmp_curve.speed * ovsmp_weights],
expansion_radii=np.ones(centers.shape[1]),
**lpot_kwargs)
# }}}
if 0:
# {{{ plot on-surface potential in 2D
pt.plot(curve_pot, label="pot")
pt.plot(density, label="dens")
pt.legend()
pt.show()
# }}}
fp.write_vtk_file("potential.vts", [
("potential", vol_pot.real)
])
if 0:
# {{{ 2D false-color plot
pt.clf()
plotval = np.log10(1e-20+np.abs(vol_pot))
im = fp.show_scalar_in_matplotlib(plotval.real)
from matplotlib.colors import Normalize
im.set_norm(Normalize(vmin=-2, vmax=1))
src = native_curve.pos
pt.plot(src[:, 0], src[:, 1], "o-k")
# close the curve
pt.plot(src[-1::-len(src)+1, 0], src[-1::-len(src)+1, 1], "o-k")
#pt.gca().set_aspect("equal", "datalim")
cb = pt.colorbar(shrink=0.9)
cb.set_label(r"$\log_{10}(\mathdefault{Error})$")
#from matplotlib.ticker import NullFormatter
#pt.gca().xaxis.set_major_formatter(NullFormatter())
#pt.gca().yaxis.set_major_formatter(NullFormatter())
fp.set_matplotlib_limits()
# }}}
else:
# {{{ 3D plots
plotval_vol = vol_pot.real
plotval_c = curve_pot.real
scale = 1
if 0:
# crop singularities--doesn't work very well
neighbors = [
np.roll(plotval_vol, 3, 0),
np.roll(plotval_vol, -3, 0),
np.roll(plotval_vol, 6, 0),
np.roll(plotval_vol, -6, 0),
]
avg = np.average(np.abs(plotval_vol))
outlier_flag = sum(
np.abs(plotval_vol-nb) for nb in neighbors) > avg
plotval_vol[outlier_flag] = sum(
nb[outlier_flag] for nb in neighbors)/len(neighbors)
fp.show_scalar_in_mayavi(scale*plotval_vol, max_val=1)
from mayavi import mlab
mlab.colorbar()
if 1:
mlab.points3d(
native_curve.pos[0],
native_curve.pos[1],
scale*plotval_c, scale_factor=0.02)
mlab.show()
#fplot.show_scalar_in_mayavi(fld_in_vol.real, max_val=5)
fplot.write_vtk_file(
"potential.vts",
[
("potential", fld_in_vol)
]
)
if 0:
def apply_op(density):
return bound_bdry_op(
queue, sigma=cl.array.to_device(queue, density), k=k).get()
from sumpy.tools import build_matrix
n = len(sigma)
mat = build_matrix(apply_op, dtype=np.float64, shape=(n, n))
import matplotlib.pyplot as pt
pt.imshow(mat)
pt.colorbar()
pt.show()
if 0:
# {{{ plot boundary field
fld_on_bdry = bound_bdry_op(queue, sigma=sigma, k=k).get()
nodes_host = density_discr.nodes().get(queue=queue)
#mlab.points3d(nodes_host[0], nodes_host[1], fld_on_bdry.real, scale_factor=0.03)
# }}}
("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,
**concrete_knl_kwargs))
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":
def main():
import logging
logging.basicConfig(level=logging.WARNING) # INFO for more progress info
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: ellipse(1, t),
starfish,
np.linspace(0, 1, nelements+1),
target_order)
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(target_order))
qbx, _ = QBXLayerPotentialSource(pre_density_discr, 4*target_order, qbx_order,
fmm_order=qbx_order+3,
target_association_tolerance=0.005).with_refinement()
density_discr = qbx.density_discr
nodes = density_discr.nodes().with_queue(queue)
angle = cl.clmath.atan2(nodes[1], nodes[0])
def op(**kwargs):
kwargs.update(kernel_kwargs)
#op = sym.d_dx(sym.S(kernel, sym.var("sigma"), **kwargs))
return sym.D(kernel, sym.var("sigma"), **kwargs)
#op = sym.S(kernel, sym.var("sigma"), qbx_forced_limit=None, **kwargs)
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)
bound_bdry_op = bind(qbx, op())
#mlab.figure(bgcolor=(1, 1, 1))
if 1:
fplot = FieldPlotter(np.zeros(2), extent=5, npoints=1000)
from pytential.target import PointsTarget
targets_dev = cl.array.to_device(queue, fplot.points)
fld_in_vol = bind(
(qbx, PointsTarget(targets_dev)),
op(qbx_forced_limit=None))(queue, sigma=sigma, k=k).get()
if enable_mayavi:
fplot.show_scalar_in_mayavi(fld_in_vol.real, max_val=5)
else:
fplot.write_vtk_file(
"potential-2d.vts",
[
("potential", fld_in_vol)
]
)
if 0:
def apply_op(density):
return bound_bdry_op(
queue, sigma=cl.array.to_device(queue, density), k=k).get()
from sumpy.tools import build_matrix
n = len(sigma)
mat = build_matrix(apply_op, dtype=np.float64, shape=(n, n))
import matplotlib.pyplot as pt
pt.imshow(mat)
pt.colorbar()
pt.show()
if enable_mayavi:
# {{{ plot boundary field
fld_on_bdry = bound_bdry_op(queue, sigma=sigma, k=k).get()
nodes_host = density_discr.nodes().get(queue=queue)
mlab.points3d(nodes_host[0], nodes_host[1],
fld_on_bdry.real, scale_factor=0.03)
# }}}
if enable_mayavi:
mlab.colorbar()
mlab.show()
def main():
import logging
logging.basicConfig(level=logging.WARNING) # INFO for more progress info
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: ellipse(1, t),
starfish,
np.linspace(0, 1, nelements + 1),
target_order)
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(target_order))
qbx, _ = QBXLayerPotentialSource(
pre_density_discr,
4 * target_order,
qbx_order,
fmm_order=qbx_order + 3,
target_association_tolerance=0.005).with_refinement()
density_discr = qbx.density_discr
nodes = density_discr.nodes().with_queue(queue)
angle = cl.clmath.atan2(nodes[1], nodes[0])
def op(**kwargs):
kwargs.update(kernel_kwargs)
#op = sym.d_dx(sym.S(kernel, sym.var("sigma"), **kwargs))
return sym.D(kernel, sym.var("sigma"), **kwargs)
#op = sym.S(kernel, sym.var("sigma"), qbx_forced_limit=None, **kwargs)
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)
bound_bdry_op = bind(qbx, op())
#mlab.figure(bgcolor=(1, 1, 1))
if 1:
fplot = FieldPlotter(np.zeros(2), extent=5, npoints=1000)
from pytential.target import PointsTarget
targets_dev = cl.array.to_device(queue, fplot.points)
fld_in_vol = bind((qbx, PointsTarget(targets_dev)),
op(qbx_forced_limit=None))(queue, sigma=sigma,
k=k).get()
if enable_mayavi:
fplot.show_scalar_in_mayavi(fld_in_vol.real, max_val=5)
else:
fplot.write_vtk_file("potential-2d.vts",
[("potential", fld_in_vol)])
if 0:
def apply_op(density):
return bound_bdry_op(queue,
sigma=cl.array.to_device(queue, density),
k=k).get()
from sumpy.tools import build_matrix
n = len(sigma)
mat = build_matrix(apply_op, dtype=np.float64, shape=(n, n))
import matplotlib.pyplot as pt
pt.imshow(mat)
pt.colorbar()
pt.show()
if enable_mayavi:
# {{{ plot boundary field
fld_on_bdry = bound_bdry_op(queue, sigma=sigma, k=k).get()
nodes_host = density_discr.nodes().get(queue=queue)
mlab.points3d(nodes_host[0],
nodes_host[1],
fld_on_bdry.real,
scale_factor=0.03)
# }}}
if enable_mayavi:
mlab.colorbar()
mlab.show()