def simple_mpi_communication_entrypoint():
cl_ctx = cl.create_some_context()
queue = cl.CommandQueue(cl_ctx)
actx = PyOpenCLArrayContext(queue, force_device_scalars=True)
from meshmode.distributed import MPIMeshDistributor, get_partition_by_pymetis
from meshmode.mesh import BTAG_ALL
from mpi4py import MPI
comm = MPI.COMM_WORLD
num_parts = comm.Get_size()
mesh_dist = MPIMeshDistributor(comm)
if mesh_dist.is_mananger_rank():
from meshmode.mesh.generation import generate_regular_rect_mesh
mesh = generate_regular_rect_mesh(a=(-1,)*2,
b=(1,)*2,
nelements_per_axis=(2,)*2)
part_per_element = get_partition_by_pymetis(mesh, num_parts)
local_mesh = mesh_dist.send_mesh_parts(mesh, part_per_element, num_parts)
else:
local_mesh = mesh_dist.receive_mesh_part()
dcoll = DiscretizationCollection(actx, local_mesh, order=5,
mpi_communicator=comm)
x = thaw(dcoll.nodes(), actx)
myfunc = actx.np.sin(np.dot(x, [2, 3]))
from grudge.dof_desc import as_dofdesc
dd_int = as_dofdesc("int_faces")
dd_vol = as_dofdesc("vol")
dd_af = as_dofdesc("all_faces")
all_faces_func = op.project(dcoll, dd_vol, dd_af, myfunc)
int_faces_func = op.project(dcoll, dd_vol, dd_int, myfunc)
bdry_faces_func = op.project(dcoll, BTAG_ALL, dd_af,
op.project(dcoll, dd_vol, BTAG_ALL, myfunc))
hopefully_zero = (
op.project(
dcoll, "int_faces", "all_faces",
dcoll.opposite_face_connection()(int_faces_func)
)
+ sum(op.project(dcoll, tpair.dd, "all_faces", tpair.int)
for tpair in op.cross_rank_trace_pairs(dcoll, myfunc))
) - (all_faces_func - bdry_faces_func)
error = actx.to_numpy(flat_norm(hopefully_zero, ord=np.inf))
print(__file__)
with np.printoptions(threshold=100000000, suppress=True):
logger.debug(hopefully_zero)
logger.info("error: %.5e", error)
assert error < 1e-14
def main(ctx_factory, dim=3, order=4, visualize=False):
cl_ctx = ctx_factory()
queue = cl.CommandQueue(cl_ctx)
actx = PyOpenCLArrayContext(
queue,
allocator=cl_tools.MemoryPool(cl_tools.ImmediateAllocator(queue)),
force_device_scalars=True,
)
from meshmode.mesh.generation import generate_regular_rect_mesh
mesh = generate_regular_rect_mesh(a=(0.0, ) * dim,
b=(1.0, ) * dim,
nelements_per_axis=(4, ) * dim)
dcoll = DiscretizationCollection(actx, mesh, order=order)
if 0:
epsilon0 = 8.8541878176e-12 # C**2 / (N m**2)
mu0 = 4 * np.pi * 1e-7 # N/A**2.
epsilon = 1 * epsilon0
mu = 1 * mu0
else:
epsilon = 1
mu = 1
from grudge.models.em import MaxwellOperator
maxwell_operator = MaxwellOperator(dcoll,
epsilon,
mu,
flux_type=0.5,
dimensions=dim)
def cavity_mode(x, t=0):
if dim == 3:
return get_rectangular_cavity_mode(actx, x, t, 1, (1, 2, 2))
else:
return get_rectangular_cavity_mode(actx, x, t, 1, (2, 3))
fields = cavity_mode(thaw(dcoll.nodes(), actx), t=0)
maxwell_operator.check_bc_coverage(mesh)
def rhs(t, w):
return maxwell_operator.operator(t, w)
dt = maxwell_operator.estimate_rk4_timestep(actx, dcoll, fields=fields)
dt_stepper = set_up_rk4("w", dt, fields, rhs)
target_steps = 60
final_t = dt * target_steps
nsteps = int(final_t / dt) + 1
logger.info("dt = %g nsteps = %d", dt, nsteps)
from grudge.shortcuts import make_visualizer
vis = make_visualizer(dcoll)
step = 0
def norm(u):
return op.norm(dcoll, u, 2)
e, h = maxwell_operator.split_eh(fields)
if visualize:
vis.write_vtk_file(f"fld-cavities-{step:04d}.vtu", [
("e", e),
("h", h),
])
for event in dt_stepper.run(t_end=final_t):
if isinstance(event, dt_stepper.StateComputed):
assert event.component_id == "w"
step += 1
e, h = maxwell_operator.split_eh(event.state_component)
norm_e0 = actx.to_numpy(norm(u=e[0]))
norm_e1 = actx.to_numpy(norm(u=e[1]))
norm_h0 = actx.to_numpy(norm(u=h[0]))
norm_h1 = actx.to_numpy(norm(u=h[1]))
logger.info(
"[%04d] t = %.5f |e0| = %.5e, |e1| = %.5e, |h0| = %.5e, |h1| = %.5e",
step, event.t, norm_e0, norm_e1, norm_h0, norm_h1)
if step % 10 == 0:
if visualize:
vis.write_vtk_file(f"fld-cavities-{step:04d}.vtu", [
("e", e),
("h", h),
])
# NOTE: These are here to ensure the solution is bounded for the
# time interval specified
assert norm_e0 < 0.5
assert norm_e1 < 0.5
assert norm_h0 < 0.5
assert norm_h1 < 0.5
def mpi_communication_entrypoint():
cl_ctx = cl.create_some_context()
queue = cl.CommandQueue(cl_ctx)
actx = PyOpenCLArrayContext(queue, force_device_scalars=True)
from mpi4py import MPI
comm = MPI.COMM_WORLD
i_local_rank = comm.Get_rank()
num_parts = comm.Get_size()
from meshmode.distributed import MPIMeshDistributor, get_partition_by_pymetis
mesh_dist = MPIMeshDistributor(comm)
dim = 2
order = 4
if mesh_dist.is_mananger_rank():
from meshmode.mesh.generation import generate_regular_rect_mesh
mesh = generate_regular_rect_mesh(a=(-0.5,)*dim,
b=(0.5,)*dim,
nelements_per_axis=(16,)*dim)
part_per_element = get_partition_by_pymetis(mesh, num_parts)
local_mesh = mesh_dist.send_mesh_parts(mesh, part_per_element, num_parts)
del mesh
else:
local_mesh = mesh_dist.receive_mesh_part()
dcoll = DiscretizationCollection(actx, local_mesh, order=order,
mpi_communicator=comm)
def source_f(actx, dcoll, t=0):
source_center = np.array([0.1, 0.22, 0.33])[:dcoll.dim]
source_width = 0.05
source_omega = 3
nodes = thaw(dcoll.nodes(), actx)
source_center_dist = flat_obj_array(
[nodes[i] - source_center[i] for i in range(dcoll.dim)]
)
return (
np.sin(source_omega*t)
* actx.np.exp(
-np.dot(source_center_dist, source_center_dist)
/ source_width**2
)
)
from grudge.models.wave import WeakWaveOperator
from meshmode.mesh import BTAG_ALL, BTAG_NONE
wave_op = WeakWaveOperator(
dcoll,
0.1,
source_f=source_f,
dirichlet_tag=BTAG_NONE,
neumann_tag=BTAG_NONE,
radiation_tag=BTAG_ALL,
flux_type="upwind"
)
fields = flat_obj_array(
dcoll.zeros(actx),
[dcoll.zeros(actx) for i in range(dcoll.dim)]
)
dt = actx.to_numpy(
2/3 * wave_op.estimate_rk4_timestep(actx, dcoll, fields=fields))
wave_op.check_bc_coverage(local_mesh)
from logpyle import LogManager, \
add_general_quantities, \
add_run_info
log_filename = None
# NOTE: LogManager hangs when using a file on a shared directory.
# log_filename = "grudge_log.dat"
logmgr = LogManager(log_filename, "w", comm)
add_run_info(logmgr)
add_general_quantities(logmgr)
def rhs(t, w):
return wave_op.operator(t, w)
dt_stepper = set_up_rk4("w", dt, fields, rhs)
final_t = 4
nsteps = int(final_t/dt)
logger.info("[%04d] dt %.5e nsteps %4d", i_local_rank, dt, nsteps)
step = 0
def norm(u):
return op.norm(dcoll, u, 2)
from time import time
t_last_step = time()
logmgr.tick_before()
for event in dt_stepper.run(t_end=final_t):
if isinstance(event, dt_stepper.StateComputed):
assert event.component_id == "w"
step += 1
logger.info("[%04d] t = %.5e |u| = %.5e ellapsed %.5e",
step, event.t,
norm(u=event.state_component[0]),
time() - t_last_step)
t_last_step = time()
logmgr.tick_after()
logmgr.tick_before()
logmgr.tick_after()
logmgr.close()
logger.info("Rank %d exiting", i_local_rank)
def main(ctx_factory,
dim=2,
order=4,
use_quad=False,
visualize=False,
flux_type="upwind"):
cl_ctx = ctx_factory()
queue = cl.CommandQueue(cl_ctx)
actx = PyOpenCLArrayContext(
queue,
allocator=cl_tools.MemoryPool(cl_tools.ImmediateAllocator(queue)),
force_device_scalars=True,
)
# {{{ parameters
# domain [0, d]^dim
d = 1.0
# number of points in each dimension
npoints = 25
# final time
final_time = 1
if use_quad:
qtag = dof_desc.DISCR_TAG_QUAD
else:
qtag = None
# }}}
# {{{ discretization
from meshmode.mesh.generation import generate_regular_rect_mesh
mesh = generate_regular_rect_mesh(a=(0, ) * dim,
b=(d, ) * dim,
npoints_per_axis=(npoints, ) * dim,
order=order)
from meshmode.discretization.poly_element import \
QuadratureSimplexGroupFactory
if use_quad:
discr_tag_to_group_factory = {
qtag: QuadratureSimplexGroupFactory(order=4 * order)
}
else:
discr_tag_to_group_factory = {}
from grudge import DiscretizationCollection
dcoll = DiscretizationCollection(
actx,
mesh,
order=order,
discr_tag_to_group_factory=discr_tag_to_group_factory)
# }}}
# {{{ advection operator
# gaussian parameters
def f_halfcircle(x):
source_center = np.array([d / 2, d / 2, d / 2])[:dim]
dist = x - source_center
return ((0.5 + 0.5 * actx.np.tanh(500 *
(-np.dot(dist, dist) + 0.4**2))) *
(0.5 + 0.5 * actx.np.tanh(500 * (dist[0]))))
def zero_inflow_bc(dtag, t=0):
dd = dof_desc.DOFDesc(dtag, qtag)
return dcoll.discr_from_dd(dd).zeros(actx)
from grudge.models.advection import VariableCoefficientAdvectionOperator
x = thaw(dcoll.nodes(), actx)
# velocity field
if dim == 1:
c = x
else:
# solid body rotation
c = flat_obj_array(np.pi * (d / 2 - x[1]), np.pi * (x[0] - d / 2),
0)[:dim]
adv_operator = VariableCoefficientAdvectionOperator(
dcoll,
c,
inflow_u=lambda t: zero_inflow_bc(BTAG_ALL, t),
quad_tag=qtag,
flux_type=flux_type)
u = f_halfcircle(x)
def rhs(t, u):
return adv_operator.operator(t, u)
dt = actx.to_numpy(
adv_operator.estimate_rk4_timestep(actx, dcoll, fields=u))
logger.info("Timestep size: %g", dt)
# }}}
# {{{ time stepping
from grudge.shortcuts import set_up_rk4
dt_stepper = set_up_rk4("u", dt, u, rhs)
plot = Plotter(actx, dcoll, order, visualize=visualize, ylim=[-0.1, 1.1])
step = 0
for event in dt_stepper.run(t_end=final_time):
if not isinstance(event, dt_stepper.StateComputed):
continue
if step % 10 == 0:
norm_u = actx.to_numpy(op.norm(dcoll, event.state_component, 2))
plot(event, "fld-var-velocity-%04d" % step)
step += 1
logger.info("[%04d] t = %.5f |u| = %.5e", step, event.t, norm_u)
# NOTE: These are here to ensure the solution is bounded for the
# time interval specified
assert norm_u < 1
def main(ctx_factory, dim=2, order=4, use_quad=False, visualize=False):
cl_ctx = ctx_factory()
queue = cl.CommandQueue(cl_ctx)
actx = PyOpenCLArrayContext(
queue,
allocator=cl_tools.MemoryPool(cl_tools.ImmediateAllocator(queue)),
force_device_scalars=True,
)
# {{{ parameters
# sphere radius
radius = 1.0
# sphere resolution
resolution = 64 if dim == 2 else 1
# final time
final_time = np.pi
# flux
flux_type = "lf"
# }}}
# {{{ discretization
if dim == 2:
from meshmode.mesh.generation import make_curve_mesh, ellipse
mesh = make_curve_mesh(
lambda t: radius * ellipse(1.0, t),
np.linspace(0.0, 1.0, resolution + 1),
order)
elif dim == 3:
from meshmode.mesh.generation import generate_icosphere
mesh = generate_icosphere(radius, order=4 * order,
uniform_refinement_rounds=resolution)
else:
raise ValueError("unsupported dimension")
discr_tag_to_group_factory = {}
if use_quad:
qtag = dof_desc.DISCR_TAG_QUAD
else:
qtag = None
from meshmode.discretization.poly_element import \
default_simplex_group_factory, \
QuadratureSimplexGroupFactory
discr_tag_to_group_factory[dof_desc.DISCR_TAG_BASE] = \
default_simplex_group_factory(base_dim=dim-1, order=order)
if use_quad:
discr_tag_to_group_factory[qtag] = \
QuadratureSimplexGroupFactory(order=4*order)
from grudge import DiscretizationCollection
dcoll = DiscretizationCollection(
actx, mesh,
discr_tag_to_group_factory=discr_tag_to_group_factory
)
volume_discr = dcoll.discr_from_dd(dof_desc.DD_VOLUME)
logger.info("ndofs: %d", volume_discr.ndofs)
logger.info("nelements: %d", volume_discr.mesh.nelements)
# }}}
# {{{ Surface advection operator
# velocity field
x = thaw(dcoll.nodes(), actx)
c = make_obj_array([-x[1], x[0], 0.0])[:dim]
def f_initial_condition(x):
return x[0]
from grudge.models.advection import SurfaceAdvectionOperator
adv_operator = SurfaceAdvectionOperator(
dcoll,
c,
flux_type=flux_type,
quad_tag=qtag
)
u0 = f_initial_condition(x)
def rhs(t, u):
return adv_operator.operator(t, u)
# check velocity is tangential
from grudge.geometry import normal
surf_normal = normal(actx, dcoll, dd=dof_desc.DD_VOLUME)
error = op.norm(dcoll, c.dot(surf_normal), 2)
logger.info("u_dot_n: %.5e", error)
# }}}
# {{{ time stepping
# FIXME: dt estimate is not necessarily valid for surfaces
dt = actx.to_numpy(
0.45 * adv_operator.estimate_rk4_timestep(actx, dcoll, fields=u0))
nsteps = int(final_time // dt) + 1
logger.info("dt: %.5e", dt)
logger.info("nsteps: %d", nsteps)
from grudge.shortcuts import set_up_rk4
dt_stepper = set_up_rk4("u", dt, u0, rhs)
plot = Plotter(actx, dcoll, order, visualize=visualize)
norm_u = actx.to_numpy(op.norm(dcoll, u0, 2))
step = 0
event = dt_stepper.StateComputed(0.0, 0, 0, u0)
plot(event, "fld-surface-%04d" % 0)
if visualize and dim == 3:
from grudge.shortcuts import make_visualizer
vis = make_visualizer(dcoll)
vis.write_vtk_file(
"fld-surface-velocity.vtu",
[
("u", c),
("n", surf_normal)
],
overwrite=True
)
df = dof_desc.DOFDesc(FACE_RESTR_INTERIOR)
face_discr = dcoll.discr_from_dd(df)
face_normal = thaw(dcoll.normal(dd=df), actx)
from meshmode.discretization.visualization import make_visualizer
vis = make_visualizer(actx, face_discr)
vis.write_vtk_file("fld-surface-face-normals.vtu", [
("n", face_normal)
], overwrite=True)
for event in dt_stepper.run(t_end=final_time, max_steps=nsteps + 1):
if not isinstance(event, dt_stepper.StateComputed):
continue
step += 1
if step % 10 == 0:
norm_u = actx.to_numpy(op.norm(dcoll, event.state_component, 2))
plot(event, "fld-surface-%04d" % step)
logger.info("[%04d] t = %.5f |u| = %.5e", step, event.t, norm_u)
# NOTE: These are here to ensure the solution is bounded for the
# time interval specified
assert norm_u < 3
def main(ctx_factory, dim=2, order=4, visualize=False):
cl_ctx = ctx_factory()
queue = cl.CommandQueue(cl_ctx)
actx = PyOpenCLArrayContext(
queue,
allocator=cl_tools.MemoryPool(cl_tools.ImmediateAllocator(queue)),
force_device_scalars=True,
)
# {{{ parameters
# domain [-d/2, d/2]^dim
d = 1.0
# number of points in each dimension
npoints = 20
# final time
final_time = 1.0
# velocity field
c = np.array([0.5] * dim)
norm_c = la.norm(c)
# flux
flux_type = "central"
# }}}
# {{{ discretization
from meshmode.mesh.generation import generate_box_mesh
mesh = generate_box_mesh(
[np.linspace(-d / 2, d / 2, npoints) for _ in range(dim)], order=order)
from grudge import DiscretizationCollection
dcoll = DiscretizationCollection(actx, mesh, order=order)
# }}}
# {{{ weak advection operator
def f(x):
return actx.np.sin(3 * x)
def u_analytic(x, t=0):
return f(-np.dot(c, x) / norm_c + t * norm_c)
from grudge.models.advection import WeakAdvectionOperator
adv_operator = WeakAdvectionOperator(
dcoll,
c,
inflow_u=lambda t: u_analytic(thaw(dcoll.nodes(dd=BTAG_ALL), actx),
t=t),
flux_type=flux_type)
nodes = thaw(dcoll.nodes(), actx)
u = u_analytic(nodes, t=0)
def rhs(t, u):
return adv_operator.operator(t, u)
dt = actx.to_numpy(
adv_operator.estimate_rk4_timestep(actx, dcoll, fields=u))
logger.info("Timestep size: %g", dt)
# }}}
# {{{ time stepping
from grudge.shortcuts import set_up_rk4
dt_stepper = set_up_rk4("u", dt, u, rhs)
plot = Plotter(actx, dcoll, order, visualize=visualize, ylim=[-1.1, 1.1])
step = 0
norm_u = 0.0
for event in dt_stepper.run(t_end=final_time):
if not isinstance(event, dt_stepper.StateComputed):
continue
if step % 10 == 0:
norm_u = actx.to_numpy(op.norm(dcoll, event.state_component, 2))
plot(event, "fld-weak-%04d" % step)
step += 1
logger.info("[%04d] t = %.5f |u| = %.5e", step, event.t, norm_u)
# NOTE: These are here to ensure the solution is bounded for the
# time interval specified
assert norm_u < 1
def main(ctx_factory, dim=2, order=4, visualize=False):
cl_ctx = cl.create_some_context()
queue = cl.CommandQueue(cl_ctx)
actx = PyOpenCLArrayContext(
queue,
allocator=cl_tools.MemoryPool(cl_tools.ImmediateAllocator(queue)),
force_device_scalars=True,
)
comm = MPI.COMM_WORLD
num_parts = comm.Get_size()
from meshmode.distributed import MPIMeshDistributor, get_partition_by_pymetis
mesh_dist = MPIMeshDistributor(comm)
if mesh_dist.is_mananger_rank():
from meshmode.mesh.generation import generate_regular_rect_mesh
mesh = generate_regular_rect_mesh(
a=(-0.5,)*dim,
b=(0.5,)*dim,
nelements_per_axis=(16,)*dim)
logger.info("%d elements", mesh.nelements)
part_per_element = get_partition_by_pymetis(mesh, num_parts)
local_mesh = mesh_dist.send_mesh_parts(mesh, part_per_element, num_parts)
del mesh
else:
local_mesh = mesh_dist.receive_mesh_part()
dcoll = DiscretizationCollection(actx, local_mesh, order=order,
mpi_communicator=comm)
def source_f(actx, dcoll, t=0):
source_center = np.array([0.1, 0.22, 0.33])[:dcoll.dim]
source_width = 0.05
source_omega = 3
nodes = thaw(dcoll.nodes(), actx)
source_center_dist = flat_obj_array(
[nodes[i] - source_center[i] for i in range(dcoll.dim)]
)
return (
np.sin(source_omega*t)
* actx.np.exp(
-np.dot(source_center_dist, source_center_dist)
/ source_width**2
)
)
from grudge.models.wave import WeakWaveOperator
from meshmode.mesh import BTAG_ALL, BTAG_NONE
wave_op = WeakWaveOperator(
dcoll,
0.1,
source_f=source_f,
dirichlet_tag=BTAG_NONE,
neumann_tag=BTAG_NONE,
radiation_tag=BTAG_ALL,
flux_type="upwind"
)
fields = flat_obj_array(
dcoll.zeros(actx),
[dcoll.zeros(actx) for i in range(dcoll.dim)]
)
dt = actx.to_numpy(
2/3 * wave_op.estimate_rk4_timestep(actx, dcoll, fields=fields))
wave_op.check_bc_coverage(local_mesh)
def rhs(t, w):
return wave_op.operator(t, w)
dt_stepper = set_up_rk4("w", dt, fields, rhs)
final_t = 10
nsteps = int(final_t/dt) + 1
if comm.rank == 0:
logger.info("dt=%g nsteps=%d", dt, nsteps)
from grudge.shortcuts import make_visualizer
vis = make_visualizer(dcoll)
step = 0
def norm(u):
return op.norm(dcoll, u, 2)
from time import time
t_last_step = time()
if visualize:
u = fields[0]
v = fields[1:]
vis.write_parallel_vtk_file(
comm,
f"fld-wave-min-mpi-{{rank:03d}}-{step:04d}.vtu",
[
("u", u),
("v", v),
]
)
for event in dt_stepper.run(t_end=final_t):
if isinstance(event, dt_stepper.StateComputed):
assert event.component_id == "w"
step += 1
l2norm = norm(u=event.state_component[0])
if step % 10 == 0:
if comm.rank == 0:
logger.info(f"step: {step} "
f"t: {time()-t_last_step} "
f"L2: {l2norm}")
if visualize:
vis.write_parallel_vtk_file(
comm,
f"fld-wave-min-mpi-{{rank:03d}}-{step:04d}.vtu",
[
("u", event.state_component[0]),
("v", event.state_component[1:]),
]
)
t_last_step = time()
# NOTE: These are here to ensure the solution is bounded for the
# time interval specified
assert l2norm < 1
def main(ctx_factory, dim=2, order=4, visualize=False):
cl_ctx = ctx_factory()
queue = cl.CommandQueue(cl_ctx)
actx = PyOpenCLArrayContext(
queue,
allocator=cl_tools.MemoryPool(cl_tools.ImmediateAllocator(queue)),
force_device_scalars=True,
)
from meshmode.mesh.generation import generate_regular_rect_mesh
mesh = generate_regular_rect_mesh(
a=(-0.5,)*dim,
b=(0.5,)*dim,
nelements_per_axis=(20,)*dim)
dcoll = DiscretizationCollection(actx, mesh, order=order)
def source_f(actx, dcoll, t=0):
source_center = np.array([0.1, 0.22, 0.33])[:dcoll.dim]
source_width = 0.05
source_omega = 3
nodes = thaw(dcoll.nodes(), actx)
source_center_dist = flat_obj_array(
[nodes[i] - source_center[i] for i in range(dcoll.dim)]
)
return (
np.sin(source_omega*t)
* actx.np.exp(
-np.dot(source_center_dist, source_center_dist)
/ source_width**2
)
)
x = thaw(dcoll.nodes(), actx)
ones = dcoll.zeros(actx) + 1
c = actx.np.where(np.dot(x, x) < 0.15, 0.1 * ones, 0.2 * ones)
from grudge.models.wave import VariableCoefficientWeakWaveOperator
from meshmode.mesh import BTAG_ALL, BTAG_NONE
wave_op = VariableCoefficientWeakWaveOperator(
dcoll,
c,
source_f=source_f,
dirichlet_tag=BTAG_NONE,
neumann_tag=BTAG_NONE,
radiation_tag=BTAG_ALL,
flux_type="upwind"
)
fields = flat_obj_array(
dcoll.zeros(actx),
[dcoll.zeros(actx) for i in range(dcoll.dim)]
)
wave_op.check_bc_coverage(mesh)
def rhs(t, w):
return wave_op.operator(t, w)
dt = actx.to_numpy(
2/3 * wave_op.estimate_rk4_timestep(actx, dcoll, fields=fields))
dt_stepper = set_up_rk4("w", dt, fields, rhs)
final_t = 1
nsteps = int(final_t/dt) + 1
logger.info("dt=%g nsteps=%d", dt, nsteps)
from grudge.shortcuts import make_visualizer
vis = make_visualizer(dcoll)
step = 0
def norm(u):
return op.norm(dcoll, u, 2)
from time import time
t_last_step = time()
if visualize:
u = fields[0]
v = fields[1:]
vis.write_vtk_file(
f"fld-var-propogation-speed-{step:04d}.vtu",
[
("u", u),
("v", v),
("c", c),
]
)
for event in dt_stepper.run(t_end=final_t):
if isinstance(event, dt_stepper.StateComputed):
assert event.component_id == "w"
step += 1
if step % 10 == 0:
logger.info(f"step: {step} t: {time()-t_last_step} "
f"L2: {norm(u=event.state_component[0])}")
if visualize:
vis.write_vtk_file(
f"fld-var-propogation-speed-{step:04d}.vtu",
[
("u", event.state_component[0]),
("v", event.state_component[1:]),
("c", c),
]
)
t_last_step = time()
# NOTE: These are here to ensure the solution is bounded for the
# time interval specified
assert norm(u=event.state_component[0]) < 1