def rotation_classes_builder(self):
from boxtree.rotation_classes import RotationClassesBuilder
return RotationClassesBuilder(self.cl_context)
def test_from_sep_siblings_rotation_classes(ctx_factory, well_sep_is_n_away):
ctx = ctx_factory()
queue = cl.CommandQueue(ctx)
dims = 3
nparticles = 10**4
dtype = np.float64
# {{{ build tree
from pyopencl.clrandom import PhiloxGenerator
rng = PhiloxGenerator(queue.context, seed=15)
from pytools.obj_array import make_obj_array
particles = make_obj_array([
rng.normal(queue, nparticles, dtype=dtype)
for i in range(dims)])
from boxtree import TreeBuilder
tb = TreeBuilder(ctx)
queue.finish()
tree, _ = tb(queue, particles, max_particles_in_box=30, debug=True)
# }}}
# {{{ build traversal
from boxtree.traversal import FMMTraversalBuilder
from boxtree.rotation_classes import RotationClassesBuilder
tg = FMMTraversalBuilder(ctx, well_sep_is_n_away=well_sep_is_n_away)
trav, _ = tg(queue, tree)
rb = RotationClassesBuilder(ctx)
result, _ = rb(queue, trav, tree)
rot_classes = result.from_sep_siblings_rotation_classes.get(queue)
rot_angles = result.from_sep_siblings_rotation_class_to_angle.get(queue)
tree = tree.get(queue=queue)
trav = trav.get(queue=queue)
centers = tree.box_centers.T
# }}}
# For each entry of from_sep_siblings, compute the source-target translation
# direction as a vector, and check that the from_sep_siblings rotation class
# in the traversal corresponds to the angle with the z-axis of the
# translation direction.
for itgt_box, tgt_ibox in enumerate(trav.target_or_target_parent_boxes):
start, end = trav.from_sep_siblings_starts[itgt_box:itgt_box+2]
seps = trav.from_sep_siblings_lists[start:end]
level_rot_classes = rot_classes[start:end]
translation_vecs = centers[tgt_ibox] - centers[seps]
theta = np.arctan2(
la.norm(translation_vecs[:, :dims - 1], axis=1),
translation_vecs[:, dims - 1])
level_rot_angles = rot_angles[level_rot_classes]
assert np.allclose(theta, level_rot_angles, atol=1e-13, rtol=1e-13)