Python Mesh.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 cells [as 别名]
def vtk_ug_to_dolfin_mesh(ug):
    """
    Create a DOLFIN Mesh from a vtkUnstructuredGrid object
    """
    if not isinstance(ug, vtk.vtkUnstructuredGrid):
        raise TypeError("Expected a 'vtkUnstructuredGrid'")
    
    # Get mesh data
    num_cells = int(ug.GetNumberOfCells())
    num_vertices = int(ug.GetNumberOfPoints())
    
    # Get topological and geometrical dimensions
    cell = ug.GetCell(0)
    gdim = int(cell.GetCellDimension())
    cell_type = cell.GetCellType()                                                                                                                                          
    if cell_type not in [vtk.VTK_TETRA, vtk.VTK_TRIANGLE]:                                                                                                                  
        raise TypeError("DOLFIN only support meshes of triangles " + \
                        "and tetrahedrons.")
    
    tdim = 3 if cell_type == vtk.VTK_TETRA else 2
    
    # Create empty DOLFIN Mesh
    mesh = Mesh()
    editor = MeshEditor()
    editor.open(mesh, tdim, gdim)
    editor.init_cells(num_cells)
    editor.init_vertices(num_vertices)
    editor.close()
    
    # Assign the cell and vertex informations directly from the vtk data
    cells_array = array_handler.vtk2array(ug.GetCells().GetData())
    
    # Get the assumed fixed size of indices and create an index array
    cell_size = cell.GetPointIds().GetNumberOfIds()
    cellinds = np.arange(len(cells_array))
    
    # Each cell_ids_size:th data point need to be deleted from the
    # index array
    ind_delete = slice(0, len(cells_array), cell_size+1)
    
    # Check that the removed value all have the same value which should
    # be the size of the data
    if not np.all(cells_array[ind_delete]==cell_size):
        raise ValueError("Expected all cells to be of the same size")
    
    cellinds = np.delete(cellinds, ind_delete)
    
    # Get cell data from mesh and make it writeable (cell data is non
    # writeable by default) and update the values
    mesh_cells = mesh.cells()
    mesh_cells.flags.writeable = True
    mesh_cells[:] = np.reshape(cells_array[cellinds], \
                              (num_cells , cell_size))
    
    # Set coordinates from vtk data
    vertex_array = array_handler.vtk2array(ug.GetPoints().GetData())
    if vertex_array.shape[1] != gdim:
        vertex_array = vertex_array[:,:gdim]
    mesh.coordinates()[:] = vertex_array
    return mesh

# 需要导入模块: from dolfin import Mesh [as 别名]
# 或者: from dolfin.Mesh import cells [as 别名]
import numpy
from dolfin import Mesh

mesh = Mesh("mesh.xml.gz")

E = mesh.cells()
M = numpy.fromfile('materials.np');




I = -numpy.ones(mesh.num_vertices())

for i in range(6):
    edx = numpy.nonzero((M>10*(i+1))*(M<10*(i+2)))[0]
    idx = (numpy.unique(E[edx,0:3])).astype(int)
    I[idx] = i*0.2

edx = numpy.nonzero(M==7)[0]
idx = (numpy.unique(E[edx,0:3])).astype(int)
I[idx] = -2;


from viper import Viper

pv = Viper(mesh, I)
pv.interactive()