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
cell_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

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.