Python Mesh.num_cells方法代码示例

# 需要导入模块: from dolfin import Mesh [as 别名]
# 或者: from dolfin.Mesh import num_cells [as 别名]
    def setupMeshes(cls, mesh, N, num_refine=0, randref=(1.0, 1.0)):
        """Create a set of N meshes based on provided mesh. Parameters
        num_refine>=0 and randref specify refinement
        adjustments. num_refine specifies the number of refinements
        per mesh, randref[0] specifies the probability that a given
        mesh is refined, and randref[1] specifies the probability that
        an element of the mesh is refined (if it is refined at all).
        """
        assert num_refine >= 0

        assert 0 < randref[0] <= 1.0
        assert 0 < randref[1] <= 1.0

        # create set of (refined) meshes
        meshes = list();
        for _ in range(N):
            m = Mesh(mesh)
            for _ in range(num_refine):
                if randref[0] == 1.0 and randref[1] == 1.0:
                    m = refine(m)
                elif random() <= randref[0]:
                    cell_markers = CellFunction("bool", m)
                    cell_markers.set_all(False)
                    cell_ids = range(m.num_cells())
                    shuffle(cell_ids)
                    num_ref_cells = int(ceil(m.num_cells() * randref[1]))
                    for cell_id in cell_ids[0:num_ref_cells]:
                        cell_markers[cell_id] = True
                    m = refine(m, cell_markers)
            meshes.append(m)
        return meshes

# 需要导入模块: from dolfin import Mesh [as 别名]
# 或者: from dolfin.Mesh import num_cells [as 别名]
    def test_convert_diffpack(self):
        from dolfin import Mesh, MPI, MeshFunction
        if MPI.num_processes() != 1:
            return
        fname = os.path.join("data", "diffpack_tet")
        dfname = fname+".xml"
        
        # Read triangle file and convert to a dolfin xml mesh file
        meshconvert.diffpack2xml(fname+".grid", dfname)

        # Read in dolfin mesh and check number of cells and vertices
        mesh = Mesh(dfname)
        self.assertEqual(mesh.num_vertices(), 27)
        self.assertEqual(mesh.num_cells(), 48)
        self.assertEqual(mesh.domains().markers(3).size(), 48)
        self.assertEqual(mesh.domains().markers(2).size(), 16)

        mf_basename = dfname.replace(".xml", "_marker_%d.xml")
        for marker, num in [(3, 9), (6, 9), (7, 3), (8, 1)]:

            mf_name = mf_basename % marker
            mf = MeshFunction("uint", mesh, mf_name)
            self.assertEqual(sum(mf.array()==marker), num)
            os.unlink(mf_name)
        
        # Clean up
        os.unlink(dfname)

# 需要导入模块: from dolfin import Mesh [as 别名]
# 或者: from dolfin.Mesh import num_cells [as 别名]
    def test_convert_diffpack_2d(self):

        from dolfin import Mesh, MPI, MeshFunction, mpi_comm_world

        fname = os.path.join(os.path.dirname(__file__), "data", "diffpack_tri")
        dfname = fname+".xml"

        # Read triangle file and convert to a dolfin xml mesh file
        meshconvert.diffpack2xml(fname+".grid", dfname)

        # Read in dolfin mesh and check number of cells and vertices
        mesh = Mesh(dfname)

        self.assertEqual(mesh.num_vertices(), 41)
        self.assertEqual(mesh.num_cells(), 64)
        self.assertEqual(len(mesh.domains().markers(2)), 64)

        mf_basename = dfname.replace(".xml", "_marker_%d.xml")
        for marker, num in [(1,10), (2,5), (3,5)]:

            mf_name = mf_basename % marker
            mf = MeshFunction("size_t", mesh, mf_name)
            self.assertEqual(sum(mf.array()==marker), num)
            os.unlink(mf_name)

        # Clean up
        os.unlink(dfname)

# 需要导入模块: from dolfin import Mesh [as 别名]
# 或者: from dolfin.Mesh import num_cells [as 别名]
    def test_convert_triangle(self): # Disabled because it fails, see FIXME below
        # test no. 1
        from dolfin import Mesh, MPI
        if MPI.num_processes() != 1:
            return
        fname = os.path.join("data", "triangle")
        dfname = fname+".xml"
        
        # Read triangle file and convert to a dolfin xml mesh file
        meshconvert.triangle2xml(fname, dfname)

        # Read in dolfin mesh and check number of cells and vertices
        mesh = Mesh(dfname)
        self.assertEqual(mesh.num_vertices(), 96)
        self.assertEqual(mesh.num_cells(), 159)

        # Clean up
        os.unlink(dfname)


        # test no. 2
        from dolfin import MPI, Mesh, MeshFunction, \
                           edges, Edge, faces, Face, \
                           SubsetIterator, facets, CellFunction
        if MPI.num_processes() != 1:
            return
        fname = os.path.join("data", "test_Triangle_3")
        dfname = fname+".xml"
        dfname0 = fname+".attr0.xml"

        # Read triangle file and convert to a dolfin xml mesh file
        meshconvert.triangle2xml(fname, dfname)

        # Read in dolfin mesh and check number of cells and vertices
        mesh = Mesh(dfname)
        mesh.init()
        mfun = MeshFunction('double', mesh, dfname0)
        self.assertEqual(mesh.num_vertices(), 58)
        self.assertEqual(mesh.num_cells(), 58)

        # Create a size_t CellFunction and assign the values based on the
        # converted Meshfunction
        cf = CellFunction("size_t", mesh)
        cf.array()[mfun.array()==10.0] = 0
        cf.array()[mfun.array()==-10.0] = 1

        # Meassure total area of cells with 1 and 2 marker
        add = lambda x, y : x+y
        area0 = reduce(add, (Face(mesh, cell.index()).area() \
                             for cell in SubsetIterator(cf, 0)), 0.0)
        area1 = reduce(add, (Face(mesh, cell.index()).area() \
                             for cell in SubsetIterator(cf, 1)), 0.0)
        total_area = reduce(add, (face.area() for face in faces(mesh)), 0.0)

        # Check that all cells in the two domains are either above or below y=0
        self.assertTrue(all(cell.midpoint().y()<0 for cell in SubsetIterator(cf, 0)))
        self.assertTrue(all(cell.midpoint().y()>0 for cell in SubsetIterator(cf, 1)))
        
        # Check that the areas add up
        self.assertAlmostEqual(area0+area1, total_area)
        
        # Measure the edge length of the two edge domains
        edge_markers = mesh.domains().facet_domains()
        self.assertTrue(edge_markers is not None)
        length0 = reduce(add, (Edge(mesh, e.index()).length() \
                            for e in SubsetIterator(edge_markers, 0)), 0.0)
        length1 = reduce(add, (Edge(mesh, e.index()).length() \
                            for e in SubsetIterator(edge_markers, 1)), 0.0)
        
        # Total length of all edges and total length of boundary edges
        total_length = reduce(add, (e.length() for e in edges(mesh)), 0.0)
        boundary_length = reduce(add, (Edge(mesh, f.index()).length() \
                          for f in facets(mesh) if f.exterior()), 0.0)
        
        # Check that the edges add up
        self.assertAlmostEqual(length0+length1, total_length)
        self.assertAlmostEqual(length1, boundary_length)

        # Clean up
        os.unlink(dfname)
        os.unlink(dfname0)