def import_from_gmsh(fname):
"Convert from gmsh to dolfin"
# read with meshio
msh = meshio.read(fname)
# create a DOLFIN mesh (assuming 2d)
gdim, tdim = 2, 2
mm = Mesh()
editor = MeshEditor()
editor.open(mm, "triangle", gdim, tdim)
npt = msh.points.shape[0]
nc = msh.get_cells_type("triangle").shape[0]
editor.init_vertices_global(npt, npt)
editor.init_cells_global(nc, nc)
for i, p in enumerate(msh.points):
editor.add_vertex(i, p[:2])
for i, c in enumerate(msh.get_cells_type("triangle")):
editor.add_cell(i, c)
editor.close()
# domains
md = mm.domains()
md.init(tdim)
markers = {}
if 'gmsh:physical' not in msh.cell_data_dict:
# no markers at all
return mm, markers
phy = msh.cell_data_dict['gmsh:physical']
if 'triangle' in phy:
for eid, val in enumerate(phy['triangle']):
md.set_marker((eid, val), 2)
if 'line' in phy:
mm.init(0, 1)
p2e = mm.topology()(0, 1)
for l, k in zip(msh.get_cells_type("line"), phy['line']):
e = set(p2e(l[0])).intersection(p2e(l[1])).pop()
md.set_marker((e, k), 1)
if 'vertex' in phy:
for eid, val in zip(msh.get_cells_type("vertex"), phy['vertex']):
md.set_marker((eid[0], val), 0)
# names
markers = tuple(
{n: v.item()
for n, (v, d) in msh.field_data.items() if d == dim}
for dim in range(tdim + 1))
return mm, markers
def convert(ifilename, handler):
""" Convert from Abaqus.
The Abaqus format first defines a node block, then there should be a number
of elements containing these nodes.
"""
# Dictionary of nodes (maps node id to coordinates)
nodes = {}
# Dictionary of elements (maps cell id to list of cell nodes)
elems = {}
# Lists of nodes for given name (key)
node_sets = {}
# Lists of cells for given name (key)
cell_sets = {}
# Lists of surfaces for given name (key) in the format:
# {'SS1': [set(['SS1_S1', 'S1']), set(['SS1_S4', 'S4'])]},
# where SS1 is the name of the surface, SS1_S1 is the name of the
# cell list whose first face is to be selected, ...
surface_sets = {}
# Open file Abaqus file
file = open(ifilename, 'r')
csv_file = csv.reader(file, delimiter=',', skipinitialspace=True)
node_set_name = None
generate = None
# Set intial state state
state = State.Init
# Read data from input file
for l in csv_file:
# Sanity check
if (len(l) == 0): print("Ooops, zero length.")
if l[0].startswith('**'): # Pass over comments
continue
elif l[0].startswith('*'): # Have a keyword
state = State.Unknown
if l[0].lower() == "*heading":
state = State.ReadHeading
elif l[0].lower() == "*part":
part_name = _read_part_name(l)
elif l[0].lower() == "*end part":
state = State.Invalid
elif l[0].lower() == "*node":
node_set_name = _create_node_list_entry(node_sets, l)
state = State.ReadNodes
elif l[0].lower() == "*element":
cell_type, cell_set_name = _read_element_keywords(cell_sets, l)
state = State.ReadCells
elif l[0].lower() == "*nset":
node_set_name, generate = _read_nset_keywords(node_sets, l)
state = State.ReadNodeSet
elif l[0].lower() == "*elset":
cell_set_name, generate = _read_elset_keywords(cell_sets, l)
if generate:
print("WARNING: generation of *elsets not tested.")
state = State.ReadCellSet
elif l[0].lower() == "*surface":
surface_set_name, generate = _read_surface_keywords(surface_sets, l)
state = State.ReadSurfaceSet
else:
print("WARNING: unrecognised Abaqus input keyword:", l[0])
state = State.Unknown
else:
if state == State.ReadHeading:
model_name = _read_heading(l)
elif state == State.ReadNodes:
node_id = int(l[0]) - 1
coords = [float(c) for c in l[1:]]
nodes[node_id] = coords
if node_set_name is not None:
node_sets[node_set_name].add(node_id)
elif state == State.ReadCells:
cell_id = int(l[0]) - 1
cell_connectivity = [int(v) - 1 for v in l[1:]]
elems[cell_id] = cell_connectivity
if cell_set_name is not None:
cell_sets[cell_set_name].add(cell_id)
elif state == State.ReadNodeSet:
try:
if generate:
n0, n1, increment = l
node_range = list(range(int(n0) - 1, int(n1) - 1, int(increment)))
node_range.append(int(n1) - 1)
node_sets[node_set_name].update(node_range)
else:
# Strip empty term at end of list, if present
if l[-1] == '': l.pop(-1)
node_range = [int(n) - 1 for n in l]
node_sets[node_set_name].update(node_range)
except:
print("WARNING: Non-integer node sets not yet supported.")
elif state == State.ReadCellSet:
try:
if generate:
n0, n1, increment = l
cell_range = list(range(int(n0) - 1, int(n1) - 1, int(increment)))
cell_range.append(int(n1) - 1)
cell_sets[cell_set_name].update(cell_range)
else:
# Strip empty term at end of list, if present
if l[-1] == '': l.pop(-1)
cell_range = [int(n) - 1 for n in l]
cell_sets[cell_set_name].update(cell_range)
except:
print("WARNING: Non-integer element sets not yet supported.")
elif state == State.ReadSurfaceSet:
# Strip empty term at end of list, if present
if l[-1] == '': l.pop(-1)
surface_sets[surface_set_name].update([tuple(l)])
elif state == State.Invalid: # part
raise Exception("Inavlid Abaqus parser state..")
# Close CSV object
file.close()
del csv_file
# Write data to XML file
# Note that vertices/cells must be consecutively numbered, which
# isn't necessarily the case in Abaqus. Therefore we enumerate and
# translate original IDs to sequence indexes if gaps are present.
# FIXME
handler.set_mesh_type("tetrahedron", 3)
process_facets = len(surface_sets) > 0
if process_facets:
try:
from dolfin import MeshEditor, Mesh
except ImportError:
_error("DOLFIN must be installed to handle Abaqus boundary regions")
mesh = Mesh()
mesh_editor = MeshEditor()
mesh_editor.open(mesh, 3, 3)
node_ids_order = {}
# Check for gaps in vertex numbering
node_ids = list(iterkeys(nodes))
if len(node_ids) > 0:
vertex_gap = (min(node_ids) != 0 or max(node_ids) != len(node_ids) - 1)
for x, y in enumerate(node_ids):
node_ids_order[y]= x # Maps Abaqus IDs to Dolfin IDs
else:
vertex_gap = True
# Check for gaps in cell numbering
elemids = list(iterkeys(elems))
if len(elemids) > 0:
cell_gap = (min(elemids) != 0 or max(elemids) != len(elemids) - 1)
else:
cell_gap = True
# Write vertices to XML file
handler.start_vertices(len(nodes))
if process_facets:
mesh_editor.init_vertices_global(len(nodes), len(nodes))
if not vertex_gap:
for v_id, v_coords in list(iteritems(nodes)):
handler.add_vertex(v_id, v_coords)
if process_facets:
mesh_editor.add_vertex(v_id, np.array(v_coords, dtype=np.float_))
else:
for idx, (v_id, v_coords) in enumerate(iteritems(nodes)):
handler.add_vertex(idx, v_coords)
if process_facets:
mesh_editor.add_vertex(idx, np.array(v_coords, dtype=np.float_))
handler.end_vertices()
# Write cells to XML file
handler.start_cells(len(elems))
if process_facets:
mesh_editor.init_cells_global(len(elems), len(elems))
if not vertex_gap and not cell_gap:
for c_index, c_data in list(iteritems(elems)):
for v_id in c_data:
if not (0 <= v_id < len(nodes)):
handler.error("Element %s references non-existent node %s" % (c_index, v_id))
handler.add_cell(c_index, c_data)
if process_facets:
c_data_tmp = np.array(c_data)
c_data_tmp.sort()
mesh_editor.add_cell(c_index, np.array(c_data_tmp, dtype=np.uintp))
elif not vertex_gap and cell_gap:
for idx, (c_index, c_data) in enumerate(iteritems(elems)):
for v_id in c_data:
if not (0 <= v_id < len(nodes)):
handler.error("Element %s references non-existent node %s" % (c_index, v_id))
handler.add_cell(idx, c_data)
if process_facets:
c_data_tmp = np.array(c_data)
c_data_tmp.sort()
mesh_editor.add_cell(idx, np.array(c_data_tmp, dtype=np.uintp))
else:
for idx, (c_id, c_data) in enumerate(iteritems(elems)):
c_nodes = []
for v_id in c_data:
try: c_nodes.append(node_ids_order[v_id])
except ValueError:
handler.error("Element %s references non-existent node %s" % (c_id, v_id))
handler.add_cell(idx, c_nodes)
if process_facets:
c_nodes.sort()
mesh_editor.add_cell(idx, np.array(c_nodes, dtype=np.uintp))
handler.end_cells()
# Write MeshValueCollections to XML file
handler.start_domains()
# Build a abaqus node ID -> dolfin cell ID map (which is not unique but that is irrelevant here)
# and its local entity.
if len(node_sets) > 0:
node_cell_map = {}
for c_dolfin_index, (c_index, c_data) in enumerate(iteritems(elems)):
c_data_tmp = np.array(c_data)
c_data_tmp.sort()
for local_entity, n_index in enumerate(c_data_tmp):
node_cell_map[n_index] = (c_dolfin_index, local_entity)
# Write vertex/node sets
dim = 0
for value, (name, node_set) in enumerate(iteritems(node_sets)):
handler.start_mesh_value_collection(name, dim, len(node_set), "uint")
for node in node_set:
try:
cell, local_entity = node_cell_map[node]
handler.add_entity_mesh_value_collection(dim, cell, value, local_entity=local_entity)
except KeyError:
print("Warning: Boundary references non-existent node %s" % node)
handler.end_mesh_value_collection()
# Write cell/element sets
dim = 3
for name, s in list(iteritems(cell_sets)):
handler.start_mesh_value_collection(name, dim, len(s), "uint")
for cell in s:
handler.add_entity_mesh_value_collection(dim, cell, 0)
handler.end_mesh_value_collection()
# Write surface sets
if process_facets:
dim = 2
nodes_facet_map = _nodes_facet_map(mesh)
data = [int(0)] * mesh.num_facets()
S1 = [0, 1, 2]
S2 = [0, 3, 1]
S3 = [1, 3, 2]
S4 = [2, 3, 0]
node_selector = {'S1': S1,
'S2': S2,
'S3': S3,
'S4': S4,
}
for index, (name, s) in enumerate(iteritems(surface_sets)):
cell_face_list = []
for cell_set_name, face_index in s:
cell_face_list += [(cell, face_index) for cell in cell_sets[cell_set_name]]
for cell, face in cell_face_list:
cell_nodes = elems[cell]
# Extract the face nodes
face_nodes = [cell_nodes[i] for i in node_selector[face]]
dolfin_face_nodes = [node_ids_order[n] for n in face_nodes]
dolfin_face_nodes.sort()
# Convert the face_nodes to dolfin IDs
face_id = nodes_facet_map[tuple(dolfin_face_nodes)]
data[face_id] = index + 1
# Create and initialise the mesh function
handler.start_meshfunction("facet_region", dim, mesh.num_facets() )
for index, physical_region in enumerate (data):
handler.add_entity_meshfunction(index, physical_region)
handler.end_meshfunction()
handler.end_domains()
def convert(ifilename, handler):
""" Convert from Abaqus.
The Abaqus format first defines a node block, then there should be a number
of elements containing these nodes.
"""
# Dictionary of nodes (maps node id to coordinates)
nodes = {}
# Dictionary of elements (maps cell id to list of cell nodes)
elems = {}
# Lists of nodes for given name (key)
node_sets = {}
# Lists of cells for given name (key)
cell_sets = {}
# Lists of surfaces for given name (key) in the format:
# {'SS1': [set(['SS1_S1', 'S1']), set(['SS1_S4', 'S4'])]},
# where SS1 is the name of the surface, SS1_S1 is the name of the
# cell list whose first face is to be selected, ...
surface_sets = {}
# Open file Abaqus file
file = open(ifilename, 'r')
csv_file = csv.reader(file, delimiter=',', skipinitialspace=True)
node_set_name = None
generate = None
# Set intial state state
state = State.Init
# Read data from input file
for l in csv_file:
# Sanity check
if (len(l) == 0): print("Ooops, zero length.")
if l[0].startswith('**'): # Pass over comments
continue
elif l[0].startswith('*'): # Have a keyword
state = State.Unknown
if l[0].lower() == "*heading":
state = State.ReadHeading
elif l[0].lower() == "*part":
part_name = _read_part_name(l)
elif l[0].lower() == "*end part":
state = State.Invalid
elif l[0].lower() == "*node":
node_set_name = _create_node_list_entry(node_sets, l)
state = State.ReadNodes
elif l[0].lower() == "*element":
cell_type, cell_set_name = _read_element_keywords(cell_sets, l)
state = State.ReadCells
elif l[0].lower() == "*nset":
node_set_name, generate = _read_nset_keywords(node_sets, l)
state = State.ReadNodeSet
elif l[0].lower() == "*elset":
cell_set_name, generate = _read_elset_keywords(cell_sets, l)
if generate:
print("WARNING: generation of *elsets not tested.")
state = State.ReadCellSet
elif l[0].lower() == "*surface":
surface_set_name, generate = _read_surface_keywords(
surface_sets, l)
state = State.ReadSurfaceSet
else:
print("WARNING: unrecognised Abaqus input keyword:", l[0])
state = State.Unknown
else:
if state == State.ReadHeading:
model_name = _read_heading(l)
elif state == State.ReadNodes:
node_id = int(l[0]) - 1
coords = [float(c) for c in l[1:]]
nodes[node_id] = coords
if node_set_name is not None:
node_sets[node_set_name].add(node_id)
elif state == State.ReadCells:
cell_id = int(l[0]) - 1
cell_connectivity = [int(v) - 1 for v in l[1:]]
elems[cell_id] = cell_connectivity
if cell_set_name is not None:
cell_sets[cell_set_name].add(cell_id)
elif state == State.ReadNodeSet:
try:
if generate:
n0, n1, increment = l
node_range = list(
range(int(n0) - 1,
int(n1) - 1, int(increment)))
node_range.append(int(n1) - 1)
node_sets[node_set_name].update(node_range)
else:
# Strip empty term at end of list, if present
if l[-1] == '': l.pop(-1)
node_range = [int(n) - 1 for n in l]
node_sets[node_set_name].update(node_range)
except:
print("WARNING: Non-integer node sets not yet supported.")
elif state == State.ReadCellSet:
try:
if generate:
n0, n1, increment = l
cell_range = list(
range(int(n0) - 1,
int(n1) - 1, int(increment)))
cell_range.append(int(n1) - 1)
cell_sets[cell_set_name].update(cell_range)
else:
# Strip empty term at end of list, if present
if l[-1] == '': l.pop(-1)
cell_range = [int(n) - 1 for n in l]
cell_sets[cell_set_name].update(cell_range)
except:
print(
"WARNING: Non-integer element sets not yet supported.")
elif state == State.ReadSurfaceSet:
# Strip empty term at end of list, if present
if l[-1] == '': l.pop(-1)
surface_sets[surface_set_name].update([tuple(l)])
elif state == State.Invalid: # part
raise Exception("Inavlid Abaqus parser state..")
# Close CSV object
file.close()
del csv_file
# Write data to XML file
# Note that vertices/cells must be consecutively numbered, which
# isn't necessarily the case in Abaqus. Therefore we enumerate and
# translate original IDs to sequence indexes if gaps are present.
# FIXME
handler.set_mesh_type("tetrahedron", 3)
process_facets = len(surface_sets) > 0
if process_facets:
try:
from dolfin import MeshEditor, Mesh
except ImportError:
_error(
"DOLFIN must be installed to handle Abaqus boundary regions")
mesh = Mesh()
mesh_editor = MeshEditor()
mesh_editor.open(mesh, 3, 3)
node_ids_order = {}
# Check for gaps in vertex numbering
node_ids = list(iterkeys(nodes))
if len(node_ids) > 0:
vertex_gap = (min(node_ids) != 0 or max(node_ids) != len(node_ids) - 1)
for x, y in enumerate(node_ids):
node_ids_order[y] = x # Maps Abaqus IDs to Dolfin IDs
else:
vertex_gap = True
# Check for gaps in cell numbering
elemids = list(iterkeys(elems))
if len(elemids) > 0:
cell_gap = (min(elemids) != 0 or max(elemids) != len(elemids) - 1)
else:
cell_gap = True
# Write vertices to XML file
handler.start_vertices(len(nodes))
if process_facets:
mesh_editor.init_vertices_global(len(nodes), len(nodes))
if not vertex_gap:
for v_id, v_coords in list(iteritems(nodes)):
handler.add_vertex(v_id, v_coords)
if process_facets:
mesh_editor.add_vertex(v_id, np.array(v_coords,
dtype=np.float_))
else:
for idx, (v_id, v_coords) in enumerate(iteritems(nodes)):
handler.add_vertex(idx, v_coords)
if process_facets:
mesh_editor.add_vertex(idx, np.array(v_coords,
dtype=np.float_))
handler.end_vertices()
# Write cells to XML file
handler.start_cells(len(elems))
if process_facets:
mesh_editor.init_cells_global(len(elems), len(elems))
if not vertex_gap and not cell_gap:
for c_index, c_data in list(iteritems(elems)):
for v_id in c_data:
if not (0 <= v_id < len(nodes)):
handler.error(
"Element %s references non-existent node %s" %
(c_index, v_id))
handler.add_cell(c_index, c_data)
if process_facets:
c_data_tmp = np.array(c_data)
c_data_tmp.sort()
mesh_editor.add_cell(c_index,
np.array(c_data_tmp, dtype=np.uintp))
elif not vertex_gap and cell_gap:
for idx, (c_index, c_data) in enumerate(iteritems(elems)):
for v_id in c_data:
if not (0 <= v_id < len(nodes)):
handler.error(
"Element %s references non-existent node %s" %
(c_index, v_id))
handler.add_cell(idx, c_data)
if process_facets:
c_data_tmp = np.array(c_data)
c_data_tmp.sort()
mesh_editor.add_cell(idx, np.array(c_data_tmp, dtype=np.uintp))
else:
for idx, (c_id, c_data) in enumerate(iteritems(elems)):
c_nodes = []
for v_id in c_data:
try:
c_nodes.append(node_ids_order[v_id])
except ValueError:
handler.error(
"Element %s references non-existent node %s" %
(c_id, v_id))
handler.add_cell(idx, c_nodes)
if process_facets:
c_nodes.sort()
mesh_editor.add_cell(idx, np.array(c_nodes, dtype=np.uintp))
handler.end_cells()
# Write MeshValueCollections to XML file
handler.start_domains()
# Build a abaqus node ID -> dolfin cell ID map (which is not unique but that is irrelevant here)
# and its local entity.
if len(node_sets) > 0:
node_cell_map = {}
for c_dolfin_index, (c_index, c_data) in enumerate(iteritems(elems)):
c_data_tmp = np.array(c_data)
c_data_tmp.sort()
for local_entity, n_index in enumerate(c_data_tmp):
node_cell_map[n_index] = (c_dolfin_index, local_entity)
# Write vertex/node sets
dim = 0
for value, (name, node_set) in enumerate(iteritems(node_sets)):
handler.start_mesh_value_collection(name, dim, len(node_set), "uint")
for node in node_set:
try:
cell, local_entity = node_cell_map[node]
handler.add_entity_mesh_value_collection(
dim, cell, value, local_entity=local_entity)
except KeyError:
print("Warning: Boundary references non-existent node %s" %
node)
handler.end_mesh_value_collection()
# Write cell/element sets
dim = 3
for name, s in list(iteritems(cell_sets)):
handler.start_mesh_value_collection(name, dim, len(s), "uint")
for cell in s:
handler.add_entity_mesh_value_collection(dim, cell, 0)
handler.end_mesh_value_collection()
# Write surface sets
if process_facets:
dim = 2
nodes_facet_map = _nodes_facet_map(mesh)
data = [int(0)] * mesh.num_facets()
S1 = [0, 1, 2]
S2 = [0, 3, 1]
S3 = [1, 3, 2]
S4 = [2, 3, 0]
node_selector = {
'S1': S1,
'S2': S2,
'S3': S3,
'S4': S4,
}
for index, (name, s) in enumerate(iteritems(surface_sets)):
cell_face_list = []
for cell_set_name, face_index in s:
cell_face_list += [(cell, face_index)
for cell in cell_sets[cell_set_name]]
for cell, face in cell_face_list:
cell_nodes = elems[cell]
# Extract the face nodes
face_nodes = [cell_nodes[i] for i in node_selector[face]]
dolfin_face_nodes = [node_ids_order[n] for n in face_nodes]
dolfin_face_nodes.sort()
# Convert the face_nodes to dolfin IDs
face_id = nodes_facet_map[tuple(dolfin_face_nodes)]
data[face_id] = index + 1
# Create and initialise the mesh function
handler.start_meshfunction("facet_region", dim, mesh.num_facets())
for index, physical_region in enumerate(data):
handler.add_entity_meshfunction(index, physical_region)
handler.end_meshfunction()
handler.end_domains()
def gmsh2xml(ifilename, handler):
"""Convert between .gmsh v2.0 format (http://www.geuz.org/gmsh/) and .xml,
parser implemented as a state machine:
0 = read 'MeshFormat'
1 = read mesh format data
2 = read 'EndMeshFormat'
3 = read 'Nodes'
4 = read number of vertices
5 = read vertices
6 = read 'EndNodes'
7 = read 'Elements'
8 = read number of cells
9 = read cells
10 = done
Afterwards, extract physical region numbers if they are defined in
the mesh file as a mesh function.
"""
print("Converting from Gmsh format (.msh, .gmsh) to DOLFIN XML format")
# The dimension of the gmsh element types supported here as well as the dolfin cell types for each dimension
gmsh_dim = {15: 0, 1: 1, 2: 2, 4: 3}
cell_type_for_dim = {1: "interval", 2: "triangle", 3: "tetrahedron" }
# the gmsh element types supported for conversion
supported_gmsh_element_types = [1, 2, 4, 15]
# Open files
ifile = open(ifilename, "r")
# Scan file for cell type
cell_type = None
highest_dim = 0
line = ifile.readline()
while line:
# Remove newline
line = line.rstrip("\n\r")
# Read dimension
if line.find("$Elements") == 0:
line = ifile.readline()
num_elements = int(line)
if num_elements == 0:
_error("No elements found in gmsh file.")
line = ifile.readline()
# Now iterate through elements to find largest dimension. Gmsh
# format might include elements of lower dimensions in the element list.
# We also need to count number of elements of correct dimensions.
# Also determine which vertices are not used.
dim_count = {0: 0, 1: 0, 2: 0, 3: 0}
vertices_used_for_dim = {0: [], 1: [], 2: [], 3: []}
# Array used to store gmsh tags for 1D (type 1/line), 2D (type 2/triangular) elements and 3D (type 4/tet) elements
tags_for_dim = {0: [], 1: [], 2: [], 3: []}
while line.find("$EndElements") == -1:
element = line.split()
elem_type = int(element[1])
num_tags = int(element[2])
if elem_type in supported_gmsh_element_types:
dim = gmsh_dim[elem_type]
if highest_dim < dim:
highest_dim = dim
node_num_list = [int(node) for node in element[3 + num_tags:]]
vertices_used_for_dim[dim].extend(node_num_list)
if num_tags > 0:
tags_for_dim[dim].append(tuple(int(tag) for tag in element[3:3+num_tags]))
dim_count[dim] += 1
else:
#TODO: output a warning here. "gmsh element type %d not supported" % elem_type
pass
line = ifile.readline()
else:
# Read next line
line = ifile.readline()
# Check that we got the cell type and set num_cells_counted
if highest_dim == 0:
_error("Unable to find cells of supported type.")
num_cells_counted = dim_count[highest_dim]
vertex_set = set(vertices_used_for_dim[highest_dim])
vertices_used_for_dim[highest_dim] = None
vertex_dict = {}
for n,v in enumerate(vertex_set):
vertex_dict[v] = n
# Step to beginning of file
ifile.seek(0)
# Set mesh type
handler.set_mesh_type(cell_type_for_dim[highest_dim], highest_dim)
# Initialise node list (gmsh does not export all vertexes in order)
nodelist = {}
# Current state
state = 0
# Write data
num_vertices_read = 0
num_cells_read = 0
# Only import the dolfin objects if facet markings exist
process_facets = False
if len(tags_for_dim[highest_dim-1]) > 0:
# first construct the mesh
try:
from dolfin import MeshEditor, Mesh
except ImportError:
_error("DOLFIN must be installed to handle Gmsh boundary regions")
mesh = Mesh()
mesh_editor = MeshEditor ()
mesh_editor.open( mesh, highest_dim, highest_dim )
process_facets = True
else:
# TODO: Output a warning or an error here
me = None
while state != 10:
# Read next line
line = ifile.readline()
if not line: break
# Skip comments
if line[0] == '#':
continue
# Remove newline
line = line.rstrip("\n\r")
if state == 0:
if line == "$MeshFormat":
state = 1
elif state == 1:
(version, file_type, data_size) = line.split()
state = 2
elif state == 2:
if line == "$EndMeshFormat":
state = 3
elif state == 3:
if line == "$Nodes":
state = 4
elif state == 4:
num_vertices = len(vertex_dict)
handler.start_vertices(num_vertices)
if process_facets:
mesh_editor.init_vertices_global(num_vertices, num_vertices)
state = 5
elif state == 5:
(node_no, x, y, z) = line.split()
node_no = int(node_no)
x,y,z = [float(xx) for xx in (x,y,z)]
if node_no in vertex_dict:
node_no = vertex_dict[node_no]
else:
continue
nodelist[int(node_no)] = num_vertices_read
handler.add_vertex(num_vertices_read, [x, y, z])
if process_facets:
if highest_dim == 1:
coords = numpy.array([x])
elif highest_dim == 2:
coords = numpy.array([x, y])
elif highest_dim == 3:
coords = numpy.array([x, y, z])
mesh_editor.add_vertex(num_vertices_read, coords)
num_vertices_read +=1
if num_vertices == num_vertices_read:
handler.end_vertices()
state = 6
elif state == 6:
if line == "$EndNodes":
state = 7
elif state == 7:
if line == "$Elements":
state = 8
elif state == 8:
handler.start_cells(num_cells_counted)
if process_facets:
mesh_editor.init_cells_global(num_cells_counted, num_cells_counted)
state = 9
elif state == 9:
element = line.split()
elem_type = int(element[1])
num_tags = int(element[2])
if elem_type in supported_gmsh_element_types:
dim = gmsh_dim[elem_type]
else:
dim = 0
if dim == highest_dim:
node_num_list = [vertex_dict[int(node)] for node in element[3 + num_tags:]]
for node in node_num_list:
if not node in nodelist:
_error("Vertex %d of %s %d not previously defined." %
(node, cell_type_for_dim[dim], num_cells_read))
cell_nodes = [nodelist[n] for n in node_num_list]
handler.add_cell(num_cells_read, cell_nodes)
if process_facets:
cell_nodes = numpy.array([nodelist[n] for n in node_num_list], dtype=numpy.uintp)
mesh_editor.add_cell(num_cells_read, cell_nodes)
num_cells_read +=1
if num_cells_counted == num_cells_read:
handler.end_cells()
if process_facets:
mesh_editor.close()
state = 10
elif state == 10:
break
# Write mesh function based on the Physical Regions defined by
# gmsh, but only if they are not all zero. All zero physical
# regions indicate that no physical regions were defined.
if highest_dim not in [1,2,3]:
_error("Gmsh tags not supported for dimension %i. Probably a bug" % dim)
tags = tags_for_dim[highest_dim]
physical_regions = tuple(tag[0] for tag in tags)
if not all(tag == 0 for tag in physical_regions):
handler.start_meshfunction("physical_region", dim, num_cells_counted)
for i, physical_region in enumerate(physical_regions):
handler.add_entity_meshfunction(i, physical_region)
handler.end_meshfunction()
# Now process the facet markers
tags = tags_for_dim[highest_dim-1]
if (len(tags) > 0) and (mesh is not None):
physical_regions = tuple(tag[0] for tag in tags)
if not all(tag == 0 for tag in physical_regions):
mesh.init(highest_dim-1,0)
# Get the facet-node connectivity information (reshape as a row of node indices per facet)
if highest_dim==1:
# for 1d meshes the mesh topology returns the vertex to vertex map, which isn't what we want
# as facets are vertices
facets_as_nodes = numpy.array([[i] for i in range(mesh.num_facets())])
else:
facets_as_nodes = mesh.topology()(highest_dim-1,0)().reshape ( mesh.num_facets(), highest_dim )
# Build the reverse map
nodes_as_facets = {}
for facet in range(mesh.num_facets()):
nodes_as_facets[tuple(facets_as_nodes[facet,:])] = facet
data = [int(0*k) for k in range(mesh.num_facets()) ]
for i, physical_region in enumerate(physical_regions):
nodes = [n-1 for n in vertices_used_for_dim[highest_dim-1][highest_dim*i:(highest_dim*i+highest_dim)]]
nodes.sort()
if physical_region != 0:
try:
index = nodes_as_facets[tuple(nodes)]
data[index] = physical_region
except IndexError:
raise Exception ( "The facet (%d) was not found to mark: %s" % (i, nodes) )
# Create and initialise the mesh function
handler.start_meshfunction("facet_region", highest_dim-1, mesh.num_facets() )
for index, physical_region in enumerate ( data ):
handler.add_entity_meshfunction(index, physical_region)
handler.end_meshfunction()
# Check that we got all data
if state == 10:
print("Conversion done")
else:
_error("Missing data, unable to convert \n\ Did you use version 2.0 of the gmsh file format?")
# Close files
ifile.close()
def gmsh2xml(ifilename, handler):
"""Convert between .gmsh v2.0 format (http://www.geuz.org/gmsh/) and .xml,
parser implemented as a state machine:
0 = read 'MeshFormat'
1 = read mesh format data
2 = read 'EndMeshFormat'
3 = read 'Nodes'
4 = read number of vertices
5 = read vertices
6 = read 'EndNodes'
7 = read 'Elements'
8 = read number of cells
9 = read cells
10 = done
Afterwards, extract physical region numbers if they are defined in
the mesh file as a mesh function.
"""
print("Converting from Gmsh format (.msh, .gmsh) to DOLFIN XML format")
# The dimension of the gmsh element types supported here as well as the dolfin cell types for each dimension
gmsh_dim = {15: 0, 1: 1, 2: 2, 4: 3}
cell_type_for_dim = {1: "interval", 2: "triangle", 3: "tetrahedron" }
# the gmsh element types supported for conversion
supported_gmsh_element_types = [1, 2, 4, 15]
# Open files
ifile = open(ifilename, "r")
# Scan file for cell type
cell_type = None
highest_dim = 0
line = ifile.readline()
while line:
# Remove newline
line = line.rstrip("\n\r")
# Read dimension
if line.find("$Elements") == 0:
line = ifile.readline()
num_elements = int(line)
if num_elements == 0:
_error("No elements found in gmsh file.")
line = ifile.readline()
# Now iterate through elements to find largest dimension. Gmsh
# format might include elements of lower dimensions in the element list.
# We also need to count number of elements of correct dimensions.
# Also determine which vertices are not used.
dim_count = {0: 0, 1: 0, 2: 0, 3: 0}
vertices_used_for_dim = {0: [], 1: [], 2: [], 3: []}
# Array used to store gmsh tags for 1D (type 1/line), 2D (type 2/triangular) elements and 3D (type 4/tet) elements
tags_for_dim = {0: [], 1: [], 2: [], 3: []}
while line.find("$EndElements") == -1:
element = line.split()
elem_type = int(element[1])
num_tags = int(element[2])
if elem_type in supported_gmsh_element_types:
dim = gmsh_dim[elem_type]
if highest_dim < dim:
highest_dim = dim
node_num_list = [int(node) for node in element[3 + num_tags:]]
vertices_used_for_dim[dim].extend(node_num_list)
if num_tags > 0:
tags_for_dim[dim].append(tuple(int(tag) for tag in element[3:3+num_tags]))
dim_count[dim] += 1
else:
#TODO: output a warning here. "gmsh element type %d not supported" % elem_type
pass
line = ifile.readline()
else:
# Read next line
line = ifile.readline()
# Check that we got the cell type and set num_cells_counted
if highest_dim == 0:
_error("Unable to find cells of supported type.")
num_cells_counted = dim_count[highest_dim]
vertex_set = set(vertices_used_for_dim[highest_dim])
vertices_used_for_dim[highest_dim] = None
vertex_dict = {}
for n,v in enumerate(vertex_set):
vertex_dict[v] = n
# Step to beginning of file
ifile.seek(0)
# Set mesh type
handler.set_mesh_type(cell_type_for_dim[highest_dim], highest_dim)
# Initialise node list (gmsh does not export all vertexes in order)
nodelist = {}
# Current state
state = 0
# Write data
num_vertices_read = 0
num_cells_read = 0
# Only import the dolfin objects if facet markings exist
process_facets = False
if len(tags_for_dim[highest_dim-1]) > 0:
# first construct the mesh
try:
from dolfin import MeshEditor, Mesh
except ImportError:
_error("DOLFIN must be installed to handle Gmsh boundary regions")
mesh = Mesh()
mesh_editor = MeshEditor ()
mesh_editor.open( mesh, highest_dim, highest_dim )
process_facets = True
else:
# TODO: Output a warning or an error here
me = None
while state != 10:
# Read next line
line = ifile.readline()
if not line: break
# Skip comments
if line[0] == '#':
continue
# Remove newline
line = line.rstrip("\n\r")
if state == 0:
if line == "$MeshFormat":
state = 1
elif state == 1:
(version, file_type, data_size) = line.split()
state = 2
elif state == 2:
if line == "$EndMeshFormat":
state = 3
elif state == 3:
if line == "$Nodes":
state = 4
elif state == 4:
num_vertices = len(vertex_dict)
handler.start_vertices(num_vertices)
if process_facets:
mesh_editor.init_vertices_global(num_vertices, num_vertices)
state = 5
elif state == 5:
(node_no, x, y, z) = line.split()
node_no = int(node_no)
x,y,z = [float(xx) for xx in (x,y,z)]
if node_no in vertex_dict:
node_no = vertex_dict[node_no]
else:
continue
nodelist[int(node_no)] = num_vertices_read
handler.add_vertex(num_vertices_read, [x, y, z])
if process_facets:
if highest_dim == 1:
coords = numpy.array([x])
elif highest_dim == 2:
coords = numpy.array([x, y])
elif highest_dim == 3:
coords = numpy.array([x, y, z])
mesh_editor.add_vertex(num_vertices_read, coords)
num_vertices_read +=1
if num_vertices == num_vertices_read:
handler.end_vertices()
state = 6
elif state == 6:
if line == "$EndNodes":
state = 7
elif state == 7:
if line == "$Elements":
state = 8
elif state == 8:
handler.start_cells(num_cells_counted)
if process_facets:
mesh_editor.init_cells_global(num_cells_counted, num_cells_counted)
state = 9
elif state == 9:
element = line.split()
elem_type = int(element[1])
num_tags = int(element[2])
if elem_type in supported_gmsh_element_types:
dim = gmsh_dim[elem_type]
else:
dim = 0
if dim == highest_dim:
node_num_list = [vertex_dict[int(node)] for node in element[3 + num_tags:]]
for node in node_num_list:
if not node in nodelist:
_error("Vertex %d of %s %d not previously defined." %
(node, cell_type_for_dim[dim], num_cells_read))
cell_nodes = [nodelist[n] for n in node_num_list]
handler.add_cell(num_cells_read, cell_nodes)
if process_facets:
cell_nodes = numpy.array([nodelist[n] for n in node_num_list], dtype=numpy.uintp)
mesh_editor.add_cell(num_cells_read, cell_nodes)
num_cells_read +=1
if num_cells_counted == num_cells_read:
handler.end_cells()
if process_facets:
mesh_editor.close()
state = 10
elif state == 10:
break
# Write mesh function based on the Physical Regions defined by
# gmsh, but only if they are not all zero. All zero physical
# regions indicate that no physical regions were defined.
if highest_dim not in [1,2,3]:
_error("Gmsh tags not supported for dimension %i. Probably a bug" % dim)
tags = tags_for_dim[highest_dim]
physical_regions = tuple(tag[0] for tag in tags)
if not all(tag == 0 for tag in physical_regions):
handler.start_meshfunction("physical_region", dim, num_cells_counted)
for i, physical_region in enumerate(physical_regions):
handler.add_entity_meshfunction(i, physical_region)
handler.end_meshfunction()
# Now process the facet markers
tags = tags_for_dim[highest_dim-1]
if (len(tags) > 0) and (mesh is not None):
physical_regions = tuple(tag[0] for tag in tags)
if not all(tag == 0 for tag in physical_regions):
mesh.init(highest_dim-1,0)
# Get the facet-node connectivity information (reshape as a row of node indices per facet)
if highest_dim==1:
# for 1d meshes the mesh topology returns the vertex to vertex map, which isn't what we want
# as facets are vertices
facets_as_nodes = numpy.array([[i] for i in range(mesh.num_facets())])
else:
facets_as_nodes = mesh.topology()(highest_dim-1,0)().reshape ( mesh.num_facets(), highest_dim )
# Build the reverse map
nodes_as_facets = {}
for facet in range(mesh.num_facets()):
nodes_as_facets[tuple(facets_as_nodes[facet,:])] = facet
data = [int(0*k) for k in range(mesh.num_facets()) ]
for i, physical_region in enumerate(physical_regions):
nodes = [n-1 for n in vertices_used_for_dim[highest_dim-1][highest_dim*i:(highest_dim*i+highest_dim)]]
nodes.sort()
if physical_region != 0:
try:
index = nodes_as_facets[tuple(nodes)]
data[index] = physical_region
except IndexError:
raise Exception ( "The facet (%d) was not found to mark: %s" % (i, nodes) )
# Create and initialise the mesh function
handler.start_meshfunction("facet_region", highest_dim-1, mesh.num_facets() )
for index, physical_region in enumerate ( data ):
handler.add_entity_meshfunction(index, physical_region)
handler.end_meshfunction()
# Check that we got all data
if state == 10:
print("Conversion done")
else:
_error("Missing data, unable to convert \n\ Did you use version 2.0 of the gmsh file format?")
# Close files
ifile.close()
def create_submesh(mesh, markers):
mpi_comm = mesh.mpi_comm()
if not has_pybind11():
mpi_comm = mpi_comm.tompi4py()
assert isinstance(markers, MeshFunctionBool)
assert markers.dim() == mesh.topology().dim()
marker_id = True
# == 1. Extract marked cells == #
# Dolfin does not support a distributed mesh that is empty on some processes.
# cbcpost gets around this by moving a single cell from the a non-empty processor to an empty one.
# Note that, however, this cannot work if the number of marked cell is less than the number of processors.
# In the interest of considering this case, we enable at least one cell (arbitrarily) on each processor.
# We find this solution acceptable for our purposes, despite the increase of the reduced mesh size,
# since we are never actually interested in solving a PDE on the reduced mesh, but rather only in
# assemblying tensors on it and extract their values at some locations.
backup_first_marker_id = None
if marker_id not in markers.array():
backup_first_marker_id = markers.array()[0]
markers.array()[0] = marker_id
assert marker_id in markers.array()
# == 2. Create submesh == #
submesh = Mesh(mesh.mpi_comm())
mesh_editor = MeshEditor()
mesh_editor.open(submesh,
mesh.ufl_cell().cellname(),
mesh.ufl_cell().topological_dimension(),
mesh.ufl_cell().geometric_dimension())
# Extract cells from mesh with specified marker_id
mesh_cell_indices = where(markers.array() == marker_id)[0]
mesh_cells = mesh.cells()[mesh_cell_indices]
mesh_global_cell_indices = sorted([mesh.topology().global_indices(mesh.topology().dim())[cell_index] for cell_index in mesh_cell_indices])
# Get vertices of extracted cells
mesh_vertex_indices = unique(mesh_cells.flatten())
mesh_global_vertex_indices = sorted([mesh.topology().global_indices(0)[vertex_index] for vertex_index in mesh_vertex_indices])
# Number vertices in a way which is independent from the number of processors. To do so ...
# ... first of all collect all vertices from all processors
allgathered_mesh_global_vertex_indices__non_empty_processors = list()
allgathered_mesh_global_vertex_indices__empty_processors = list()
for r in range(mpi_comm.size):
backup_first_marker_id_r = mpi_comm.bcast(backup_first_marker_id, root=r)
if backup_first_marker_id_r is None:
allgathered_mesh_global_vertex_indices__non_empty_processors.extend(mpi_comm.bcast(mesh_global_vertex_indices, root=r))
else:
allgathered_mesh_global_vertex_indices__empty_processors.extend(mpi_comm.bcast(mesh_global_vertex_indices, root=r))
allgathered_mesh_global_vertex_indices__non_empty_processors = sorted(unique(allgathered_mesh_global_vertex_indices__non_empty_processors))
allgathered_mesh_global_vertex_indices__empty_processors = sorted(unique(allgathered_mesh_global_vertex_indices__empty_processors))
# ... then create a dict that will contain the map from mesh global vertex index to submesh global vertex index.
# ... Here make sure to number first "real" vertices (those coming from non empty processors), since the other ones
# ... are just a side effect of the current partitioning!
allgathered_mesh_to_submesh_vertex_global_indices = dict()
_submesh_vertex_global_index = 0
for mesh_vertex_global_index in allgathered_mesh_global_vertex_indices__non_empty_processors:
assert mesh_vertex_global_index not in allgathered_mesh_to_submesh_vertex_global_indices
allgathered_mesh_to_submesh_vertex_global_indices[mesh_vertex_global_index] = _submesh_vertex_global_index
_submesh_vertex_global_index += 1
for mesh_vertex_global_index in allgathered_mesh_global_vertex_indices__empty_processors:
if mesh_vertex_global_index not in allgathered_mesh_to_submesh_vertex_global_indices:
allgathered_mesh_to_submesh_vertex_global_indices[mesh_vertex_global_index] = _submesh_vertex_global_index
_submesh_vertex_global_index += 1
# Number cells in a way which is independent from the number of processors. To do so ...
# ... first of all collect all cells from all processors
allgathered_mesh_global_cell_indices__non_empty_processors = list()
allgathered_mesh_global_cell_indices__empty_processors = list()
for r in range(mpi_comm.size):
backup_first_marker_id_r = mpi_comm.bcast(backup_first_marker_id, root=r)
if backup_first_marker_id_r is None:
allgathered_mesh_global_cell_indices__non_empty_processors.extend(mpi_comm.bcast(mesh_global_cell_indices, root=r))
else:
allgathered_mesh_global_cell_indices__empty_processors.extend(mpi_comm.bcast(mesh_global_cell_indices, root=r))
allgathered_mesh_global_cell_indices__non_empty_processors = sorted(unique(allgathered_mesh_global_cell_indices__non_empty_processors))
allgathered_mesh_global_cell_indices__empty_processors = sorted(unique(allgathered_mesh_global_cell_indices__empty_processors))
# ... then create a dict that will contain the map from mesh global cell index to submesh global cell index.
# ... Here make sure to number first "real" vertices (those coming from non empty processors), since the other ones
# ... are just a side effect of the current partitioning!
allgathered_mesh_to_submesh_cell_global_indices = dict()
_submesh_cell_global_index = 0
for mesh_cell_global_index in allgathered_mesh_global_cell_indices__non_empty_processors:
assert mesh_cell_global_index not in allgathered_mesh_to_submesh_cell_global_indices
allgathered_mesh_to_submesh_cell_global_indices[mesh_cell_global_index] = _submesh_cell_global_index
_submesh_cell_global_index += 1
for mesh_cell_global_index in allgathered_mesh_global_cell_indices__empty_processors:
assert mesh_cell_global_index not in allgathered_mesh_to_submesh_cell_global_indices
allgathered_mesh_to_submesh_cell_global_indices[mesh_cell_global_index] = _submesh_cell_global_index
_submesh_cell_global_index += 1
# Also create a mapping from mesh local vertex index to submesh local vertex index.
mesh_to_submesh_vertex_local_indices = dict(zip(mesh_vertex_indices, list(range(len(mesh_vertex_indices)))))
# Also create a mapping from mesh local cell index to submesh local cell index.
mesh_to_submesh_cell_local_indices = dict(zip(mesh_cell_indices, list(range(len(mesh_cell_indices)))))
# Now, define submesh cells
submesh_cells = list()
for i, c in enumerate(mesh_cells):
submesh_cells.append([mesh_to_submesh_vertex_local_indices[j] for j in c])
# Store vertices as submesh_vertices[local_index] = (global_index, coordinates)
submesh_vertices = dict()
for mesh_vertex_local_index, submesh_vertex_local_index in mesh_to_submesh_vertex_local_indices.items():
submesh_vertices[submesh_vertex_local_index] = (
allgathered_mesh_to_submesh_vertex_global_indices[mesh.topology().global_indices(0)[mesh_vertex_local_index]],
mesh.coordinates()[mesh_vertex_local_index]
)
# Collect the global number of vertices and cells
global_num_cells = mpi_comm.allreduce(len(submesh_cells), op=SUM)
global_num_vertices = len(allgathered_mesh_to_submesh_vertex_global_indices)
# Fill in mesh_editor
mesh_editor.init_vertices_global(len(submesh_vertices), global_num_vertices)
mesh_editor.init_cells_global(len(submesh_cells), global_num_cells)
for local_index, cell_vertices in enumerate(submesh_cells):
if has_pybind11():
mesh_editor.add_cell(local_index, cell_vertices)
else:
mesh_editor.add_cell(local_index, *cell_vertices)
for local_index, (global_index, coordinates) in submesh_vertices.items():
mesh_editor.add_vertex_global(local_index, global_index, coordinates)
mesh_editor.close()
# Initialize topology
submesh.topology().init(0, len(submesh_vertices), global_num_vertices)
submesh.topology().init(mesh.ufl_cell().topological_dimension(), len(submesh_cells), global_num_cells)
# Correct the global index of cells
for local_index in range(len(submesh_cells)):
submesh.topology().set_global_index(
submesh.topology().dim(),
local_index,
allgathered_mesh_to_submesh_cell_global_indices[mesh_global_cell_indices[local_index]]
)
# == 3. Store (local) mesh to/from submesh map for cells, facets and vertices == #
# Cells
submesh.mesh_to_submesh_cell_local_indices = mesh_to_submesh_cell_local_indices
submesh.submesh_to_mesh_cell_local_indices = mesh_cell_indices
# Vertices
submesh.mesh_to_submesh_vertex_local_indices = mesh_to_submesh_vertex_local_indices
submesh.submesh_to_mesh_vertex_local_indices = mesh_vertex_indices
# Facets
mesh_vertices_to_mesh_facets = dict()
mesh_facets_to_mesh_vertices = dict()
for mesh_cell_index in mesh_cell_indices:
mesh_cell = Cell(mesh, mesh_cell_index)
for mesh_facet in facets(mesh_cell):
mesh_facet_vertices = list()
for mesh_facet_vertex in vertices(mesh_facet):
mesh_facet_vertices.append(mesh_facet_vertex.index())
mesh_facet_vertices = tuple(sorted(mesh_facet_vertices))
if mesh_facet_vertices in mesh_vertices_to_mesh_facets:
assert mesh_vertices_to_mesh_facets[mesh_facet_vertices] == mesh_facet.index()
else:
mesh_vertices_to_mesh_facets[mesh_facet_vertices] = mesh_facet.index()
if mesh_facet.index() in mesh_facets_to_mesh_vertices:
assert mesh_facets_to_mesh_vertices[mesh_facet.index()] == mesh_facet_vertices
else:
mesh_facets_to_mesh_vertices[mesh_facet.index()] = mesh_facet_vertices
submesh_vertices_to_submesh_facets = dict()
submesh_facets_to_submesh_vertices = dict()
for submesh_facet in facets(submesh):
submesh_facet_vertices = list()
for submesh_facet_vertex in vertices(submesh_facet):
submesh_facet_vertices.append(submesh_facet_vertex.index())
submesh_facet_vertices = tuple(sorted(submesh_facet_vertices))
assert submesh_facet_vertices not in submesh_vertices_to_submesh_facets
submesh_vertices_to_submesh_facets[submesh_facet_vertices] = submesh_facet.index()
assert submesh_facet.index() not in submesh_facets_to_submesh_vertices
submesh_facets_to_submesh_vertices[submesh_facet.index()] = submesh_facet_vertices
mesh_to_submesh_facets_local_indices = dict()
for (mesh_facet_index, mesh_vertices) in mesh_facets_to_mesh_vertices.items():
submesh_vertices = tuple(sorted([submesh.mesh_to_submesh_vertex_local_indices[mesh_vertex] for mesh_vertex in mesh_vertices]))
submesh_facet_index = submesh_vertices_to_submesh_facets[submesh_vertices]
mesh_to_submesh_facets_local_indices[mesh_facet_index] = submesh_facet_index
submesh_to_mesh_facets_local_indices = dict()
for (submesh_facet_index, submesh_vertices) in submesh_facets_to_submesh_vertices.items():
mesh_vertices = tuple(sorted([submesh.submesh_to_mesh_vertex_local_indices[submesh_vertex] for submesh_vertex in submesh_vertices]))
mesh_facet_index = mesh_vertices_to_mesh_facets[mesh_vertices]
submesh_to_mesh_facets_local_indices[submesh_facet_index] = mesh_facet_index
submesh.mesh_to_submesh_facet_local_indices = mesh_to_submesh_facets_local_indices
submesh.submesh_to_mesh_facet_local_indices = list()
assert min(submesh_to_mesh_facets_local_indices.keys()) == 0
assert max(submesh_to_mesh_facets_local_indices.keys()) == len(submesh_to_mesh_facets_local_indices.keys()) - 1
for submesh_facet_index in range(len(submesh_to_mesh_facets_local_indices)):
submesh.submesh_to_mesh_facet_local_indices.append(submesh_to_mesh_facets_local_indices[submesh_facet_index])
# == 3bis. Prepare (temporary) global indices of facets == #
# Wrapper to DistributedMeshTools::number_entities
if has_pybind11():
cpp_code = """
#include <pybind11/pybind11.h>
#include <dolfin/mesh/DistributedMeshTools.h>
#include <dolfin/mesh/Mesh.h>
void initialize_global_indices(std::shared_ptr<dolfin::Mesh> mesh, std::size_t dim)
{
dolfin::DistributedMeshTools::number_entities(*mesh, dim);
}
PYBIND11_MODULE(SIGNATURE, m)
{
m.def("initialize_global_indices", &initialize_global_indices);
}
"""
initialize_global_indices = compile_cpp_code(cpp_code).initialize_global_indices
else:
cpp_code = """
void initialize_global_indices(Mesh & mesh, std::size_t dim)
{
DistributedMeshTools::number_entities(mesh, dim);
}
"""
initialize_global_indices = compile_extension_module(cpp_code, additional_system_headers=["dolfin/mesh/DistributedMeshTools.h"]).initialize_global_indices
initialize_global_indices(mesh, mesh.topology().dim() - 1)
# Prepare global indices of facets
mesh_facets_local_to_global_indices = dict()
for mesh_cell_index in mesh_cell_indices:
mesh_cell = Cell(mesh, mesh_cell_index)
for mesh_facet in facets(mesh_cell):
mesh_facets_local_to_global_indices[mesh_facet.index()] = mesh_facet.global_index()
mesh_facets_global_indices_in_submesh = list()
for mesh_facet_local_index in mesh_to_submesh_facets_local_indices.keys():
mesh_facets_global_indices_in_submesh.append(mesh_facets_local_to_global_indices[mesh_facet_local_index])
allgathered__mesh_facets_global_indices_in_submesh = list()
for r in range(mpi_comm.size):
allgathered__mesh_facets_global_indices_in_submesh.extend(mpi_comm.bcast(mesh_facets_global_indices_in_submesh, root=r))
allgathered__mesh_facets_global_indices_in_submesh = sorted(set(allgathered__mesh_facets_global_indices_in_submesh))
mesh_to_submesh_facets_global_indices = dict()
for (submesh_facet_global_index, mesh_facet_global_index) in enumerate(allgathered__mesh_facets_global_indices_in_submesh):
mesh_to_submesh_facets_global_indices[mesh_facet_global_index] = submesh_facet_global_index
submesh_facets_local_to_global_indices = dict()
for (submesh_facet_local_index, mesh_facet_local_index) in submesh_to_mesh_facets_local_indices.items():
submesh_facets_local_to_global_indices[submesh_facet_local_index] = mesh_to_submesh_facets_global_indices[mesh_facets_local_to_global_indices[mesh_facet_local_index]]
# == 4. Assign shared vertices == #
shared_entities_dimensions = {
"vertex": 0,
"facet": submesh.topology().dim() - 1,
"cell": submesh.topology().dim()
}
shared_entities_class = {
"vertex": Vertex,
"facet": Facet,
"cell": Cell
}
shared_entities_iterator = {
"vertex": vertices,
"facet": facets,
"cell": cells
}
shared_entities_submesh_global_index_getter = {
"vertex": lambda entity: entity.global_index(),
"facet": lambda entity: submesh_facets_local_to_global_indices[entity.index()],
"cell": lambda entity: entity.global_index()
}
for entity_type in ["vertex", "facet", "cell"]: # do not use .keys() because the order is important
dim = shared_entities_dimensions[entity_type]
class_ = shared_entities_class[entity_type]
iterator = shared_entities_iterator[entity_type]
submesh_global_index_getter = shared_entities_submesh_global_index_getter[entity_type]
# Get shared entities from mesh. A subset of these will end being shared entities also the submesh
# (thanks to the fact that we do not redistribute cells from one processor to another)
if mpi_comm.size > 1: # some entities may not be initialized in serial, since they are not needed
assert mesh.topology().have_shared_entities(dim), "Mesh shared entities have not been initialized for dimension " + str(dim)
if mesh.topology().have_shared_entities(dim): # always true in parallel (when really needed)
# However, it may happen that an entity which has been selected is not shared anymore because only one of
# the sharing processes has it in the submesh. For instance, consider the case
# of two cells across the interface (located on a facet f) between two processors. It may happen that
# only one of the two cells is selected: the facet f and its vertices are not shared anymore!
# For this reason, we create a new dict from global entity index to processors sharing them. Thus ...
# ... first of all get global indices corresponding to local entities
if entity_type in ["vertex", "cell"]:
assert submesh.topology().have_global_indices(dim), "Submesh global indices have not been initialized for dimension " + str(dim)
submesh_local_entities_global_index = list()
submesh_local_entities_global_to_local_index = dict()
for entity in iterator(submesh):
local_entity_index = entity.index()
global_entity_index = submesh_global_index_getter(entity)
submesh_local_entities_global_index.append(global_entity_index)
submesh_local_entities_global_to_local_index[global_entity_index] = local_entity_index
# ... then gather all global indices from all processors
gathered__submesh_local_entities_global_index = list() # over processor id
for r in range(mpi_comm.size):
gathered__submesh_local_entities_global_index.append(mpi_comm.bcast(submesh_local_entities_global_index, root=r))
# ... then create dict from global index to processors sharing it
submesh_shared_entities__global = dict()
for r in range(mpi_comm.size):
for global_entity_index in gathered__submesh_local_entities_global_index[r]:
if global_entity_index not in submesh_shared_entities__global:
submesh_shared_entities__global[global_entity_index] = list()
submesh_shared_entities__global[global_entity_index].append(r)
# ... and finally popuplate shared entities dict, which is the same as the dict above except that
# the current processor rank is removed and a local indexing is used
submesh_shared_entities = dict() # from local index to list of integers
for (global_entity_index, processors) in submesh_shared_entities__global.items():
if (
mpi_comm.rank in processors # only local entities
and
len(processors) > 1 # it was still shared after submesh extraction
):
other_processors_list = list(processors)
other_processors_list.remove(mpi_comm.rank)
other_processors = array(other_processors_list, dtype=uintp)
submesh_shared_entities[submesh_local_entities_global_to_local_index[global_entity_index]] = other_processors
# Need an extension module to populate shared_entities because in python each call to shared_entities
# returns a temporary.
if has_pybind11():
cpp_code = """
#include <Eigen/Core>
#include <pybind11/pybind11.h>
#include <pybind11/eigen.h>
#include <dolfin/mesh/Mesh.h>
using OtherProcesses = Eigen::Ref<const Eigen::Matrix<std::size_t, Eigen::Dynamic, 1>>;
void set_shared_entities(std::shared_ptr<dolfin::Mesh> submesh, std::size_t idx, const OtherProcesses other_processes, std::size_t dim)
{
std::set<unsigned int> set_other_processes;
for (std::size_t i(0); i < other_processes.size(); i++)
set_other_processes.insert(other_processes[i]);
submesh->topology().shared_entities(dim)[idx] = set_other_processes;
}
PYBIND11_MODULE(SIGNATURE, m)
{
m.def("set_shared_entities", &set_shared_entities);
}
"""
set_shared_entities = compile_cpp_code(cpp_code).set_shared_entities
else:
cpp_code = """
void set_shared_entities(Mesh & submesh, std::size_t idx, const Array<std::size_t>& other_processes, std::size_t dim)
{
std::set<unsigned int> set_other_processes;
for (std::size_t i(0); i < other_processes.size(); i++)
set_other_processes.insert(other_processes[i]);
submesh.topology().shared_entities(dim)[idx] = set_other_processes;
}
"""
set_shared_entities = compile_extension_module(cpp_code).set_shared_entities
for (submesh_entity_local_index, other_processors) in submesh_shared_entities.items():
set_shared_entities(submesh, submesh_entity_local_index, other_processors, dim)
log(DEBUG, "Local indices of shared entities for dimension " + str(dim) + ": " + str(list(submesh.topology().shared_entities(0).keys())))
log(DEBUG, "Global indices of shared entities for dimension " + str(dim) + ": " + str([class_(submesh, local_index).global_index() for local_index in submesh.topology().shared_entities(dim).keys()]))
# == 5. Also initialize submesh facets global indices, now that shared facets have been computed == #
initialize_global_indices(submesh, submesh.topology().dim() - 1) # note that DOLFIN might change the numbering when compared to the one at 3bis
# == 6. Restore backup_first_marker_id and return == #
if backup_first_marker_id is not None:
markers.array()[0] = backup_first_marker_id
return submesh