From 68c870eec9e622a41e4579c92bc287acfac6eaa5 Mon Sep 17 00:00:00 2001
From: ellis <eshoag2@illinois.edu>
Date: Tue, 14 Feb 2017 12:20:53 -0600
Subject: [PATCH] partition_mesh works with multiple MeshElementGroups
---
meshmode/mesh/processing.py | 45 +++++++++++++++++++++++--------------
test/test_meshmode.py | 23 ++++++++++---------
2 files changed, 41 insertions(+), 27 deletions(-)
diff --git a/meshmode/mesh/processing.py b/meshmode/mesh/processing.py
index 00b7a8bf..28d146b7 100644
--- a/meshmode/mesh/processing.py
+++ b/meshmode/mesh/processing.py
@@ -66,30 +66,39 @@ def partition_mesh(mesh, part_per_element, part_nr):
# The set of vertex indices we need.
index_set = set()
-
+ skip_groups = []
+ num_prev_elems = 0
start_idx = 0
for group_nr in range(num_groups):
mesh_group = mesh.groups[group_nr]
# Find the index of first element in the next group
end_idx = len(queried_elems)
- for idx in range(len(queried_elems)):
- if queried_elems[idx] - start_idx > mesh_group.nelements:
+ for idx in range(start_idx, len(queried_elems)):
+ if queried_elems[idx] - num_prev_elems >= mesh_group.nelements:
end_idx = idx
break
- elems = queried_elems[start_idx:end_idx]
+ if start_idx == end_idx:
+ skip_groups.append(group_nr)
+ new_indices.append(np.array([]))
+ new_nodes.append(np.array([]))
+ num_prev_elems += mesh_group.nelements
+ continue
+
+ elems = queried_elems[start_idx:end_idx] - num_prev_elems
new_indices.append(mesh_group.vertex_indices[elems])
new_nodes.append(
- np.zeros((mesh.ambient_dim, len(queried_elems), mesh_group.nunit_nodes)))
+ np.zeros((mesh.ambient_dim, end_idx - start_idx, mesh_group.nunit_nodes)))
for i in range(mesh.ambient_dim):
for j in range(start_idx, end_idx):
- elems = queried_elems[j]
- new_nodes[group_nr][i, j, :] = mesh_group.nodes[i, elems, :]
+ elems = queried_elems[j] - num_prev_elems
+ new_nodes[group_nr][i, j - start_idx, :] = mesh_group.nodes[i, elems, :]
index_set |= set(new_indices[group_nr].ravel())
+ num_prev_elems += mesh_group.nelements
start_idx = end_idx
# A sorted np.array of vertex indices we need (without duplicates).
@@ -99,22 +108,24 @@ def partition_mesh(mesh, part_per_element, part_nr):
for dim in range(mesh.ambient_dim):
new_vertices[dim] = mesh.vertices[dim][required_indices]
- # Our indices need to be in range [0, len(mesh_group.nelements)].
+ # Our indices need to be in range [0, len(mesh.nelements)].
for group_nr in range(num_groups):
- for i in range(len(new_indices[group_nr])):
- for j in range(len(new_indices[group_nr][0])):
- original_index = new_indices[group_nr][i, j]
- new_indices[group_nr][i, j] = np.where(
- required_indices == original_index)[0]
+ if not group_nr in skip_groups:
+ for i in range(len(new_indices[group_nr])):
+ for j in range(len(new_indices[group_nr][0])):
+ original_index = new_indices[group_nr][i, j]
+ new_indices[group_nr][i, j] = np.where(
+ required_indices == original_index)[0]
from meshmode.mesh import SimplexElementGroup, Mesh
new_mesh_groups = []
for group_nr in range(num_groups):
- mesh_group = mesh.groups[group_nr]
- new_mesh_groups.append(
- SimplexElementGroup(mesh_group.order, new_indices[group_nr],
- new_nodes[group_nr], unit_nodes=mesh_group.unit_nodes))
+ if not group_nr in skip_groups:
+ mesh_group = mesh.groups[group_nr]
+ new_mesh_groups.append(
+ SimplexElementGroup(mesh_group.order, new_indices[group_nr],
+ new_nodes[group_nr], unit_nodes=mesh_group.unit_nodes))
part_mesh = Mesh(new_vertices, new_mesh_groups)
diff --git a/test/test_meshmode.py b/test/test_meshmode.py
index 4cdffd85..30b5e001 100644
--- a/test/test_meshmode.py
+++ b/test/test_meshmode.py
@@ -50,7 +50,7 @@ logger = logging.getLogger(__name__)
# {{{ partition_mesh
-@pytest.mark.parametrize("mesh_type", ["torus", "box"])
+@pytest.mark.parametrize("mesh_type", ["torus", "boxes"])
def test_partition_mesh(mesh_type):
if mesh_type == "torus":
from meshmode.mesh.generation import generate_torus
@@ -67,11 +67,13 @@ def test_partition_mesh(mesh_type):
assert part_mesh1.nelements == 4
assert part_mesh2.nelements == 2
- elif mesh_type == "box":
- from meshmode.mesh.generation import generate_box_mesh
- seg = np.linspace(0, 1, 10)
- axis_coords = (seg, seg, seg)
- mesh = generate_box_mesh(axis_coords)
+ elif mesh_type == "boxes":
+ from meshmode.mesh.generation import generate_regular_rect_mesh
+ mesh1 = generate_regular_rect_mesh(a=(0, 0, 0), b=(1, 1, 1), n=(5, 5, 5))
+ mesh2 = generate_regular_rect_mesh(a=(2, 2, 2), b=(3, 3, 3), n=(5, 5, 5))
+
+ from meshmode.mesh.processing import merge_disjoint_meshes
+ mesh = merge_disjoint_meshes([mesh1, mesh2])
adjacency_list = np.zeros((mesh.nelements,), dtype=set)
for elem in range(mesh.nelements):
@@ -81,12 +83,13 @@ def test_partition_mesh(mesh_type):
adjacency_list[elem].add(mesh.nodal_adjacency.neighbors[n])
from pymetis import part_graph
- (_, part_per_element) = part_graph(3, adjacency=adjacency_list)
+ (_, p) = part_graph(3, adjacency=adjacency_list)
+ part_per_element = np.array(p)
from meshmode.mesh.processing import partition_mesh
- (part_mesh0, _) = partition_mesh(mesh, np.array(part_per_element), 0)
- (part_mesh1, _) = partition_mesh(mesh, np.array(part_per_element), 1)
- (part_mesh2, _) = partition_mesh(mesh, np.array(part_per_element), 2)
+ (part_mesh0, _) = partition_mesh(mesh, part_per_element, 0)
+ (part_mesh1, _) = partition_mesh(mesh, part_per_element, 1)
+ (part_mesh2, _) = partition_mesh(mesh, part_per_element, 2)
assert mesh.nelements == (part_mesh0.nelements
+ part_mesh1.nelements + part_mesh2.nelements)
--
GitLab