Cell

class dolfin.cpp.mesh.Cell(*args)

Bases: dolfin.cpp.mesh.MeshEntity

A Cell is a MeshEntity of topological codimension 0.

Overloaded versions

• Cell()

  Create empty cell

• Cell(mesh, index)

  Create cell on given mesh with given index

  Arguments

  mesh (Mesh)

  The mesh.

  index (int)

  The index.

cell_normal()

Compute normal to cell itself (viewed as embedded in 3D)

Returns

Point

Normal of the cell

collides()

Overloaded versions

• collides(point)

  Check whether given point collides with cell

  Arguments

  point (Point)

  The point to be checked.

  Returns

  bool

  True iff point collides with cell.

• collides(entity)

  Check whether given entity collides with cell

  Arguments

  entity (MeshEntity)

  The cell to be checked.

  Returns

  bool

  True iff entity collides with cell.

contains()

Check whether given point is contained in cell. This function is identical to the function collides(point).

Arguments

point (Point)

The point to be checked.

Returns

bool

True iff point is contained in cell.

diameter()

Compute diameter of cell

Returns

float

The diameter of the cell.

Example

Note

No example code available for this function.

distance()

Compute distance to given point.

Arguments

point (Point)

The point.

Returns

float

The distance to the point.

facet_area()

Compute the area/length of given facet with respect to the cell

Arguments

facet (int)

Index of the facet.

Returns

float

Area/length of the facet.

get_cell_data()

Fill UFC cell with miscellaneous data

get_cell_topology()

Fill UFC cell with topology data

get_vertex_coordinates()

Overloaded versions

• get_vertex_coordinates(coordinates)

  Get cell vertex coordinates

• get_vertex_coordinates(coordinates)

  Get cell vertex coordinates

inradius()

Compute inradius of cell

Returns

float

Radius of the sphere inscribed in the cell.

Example

Note

No example code available for this function.

normal()

Overloaded versions

• normal(facet, i)

  Compute component i of normal of given facet with respect to the cell

  Arguments

  facet (int)

  Index of facet.

  i (int)

  Component.

  Returns

  float

  Component i of the normal of the facet.

• normal(facet)

  Compute normal of given facet with respect to the cell

  Arguments

  facet (int)

  Index of facet.

  Returns

  Point

  Normal of the facet.

num_vertices()

Return number of vertices of cell

order()

Order entities locally

Arguments

global_vertex_indices (numpy.array(int))

The global vertex indices.

ordered()

Check if entities are ordered

Arguments

global_vertex_indices (numpy.array(int))

The global vertex indices.

Returns

bool

True iff ordered.

orientation()

Overloaded versions

• orientation()

  Compute orientation of cell

  Returns

  int

  Orientation of the cell (0 is ‘up’/’right’, 1 is ‘down’/’left’)

• orientation(up)

  Compute orientation of cell relative to given ‘up’ direction

  Arguments

  up (Point)

  The direction defined as ‘up’

  Returns

  int

  Orientation of the cell (0 is ‘same’, 1 is ‘opposite’)

radius_ratio()

Compute ratio of inradius to circumradius times dim for cell. Useful as cell quality measure. Returns 1. for equilateral and 0. for degenerate cell. See Jonathan Richard Shewchuk: What Is a Good Linear Finite Element?, online: http://www.cs.berkeley.edu/~jrs/papers/elemj.pdf

Returns

float

topological_dimension * inradius / circumradius

Example

Note

No example code available for this function.

squared_distance()

Compute squared distance to given point.

Arguments

point (Point)

The point.

Returns

float

The squared distance to the point.

thisown None

The membership flag

triangulate_intersection()

Compute triangulation of intersection with given entity

Arguments

entity (MeshEntity)

The entity with which to intersect.

Returns

numpy.array(float)

A flattened array of simplices of dimension num_simplices x num_vertices x gdim = num_simplices x (tdim + 1) x gdim

type()

Return type of cell

volume()

Compute (generalized) volume of cell

Returns

float

The volume of the cell.

Example

Note

No example code available for this function.