Adjacency¶

isotile.AdjacencyKind `module-attribute` ¶

AdjacencyKind = Literal['edge', 'vertex', 'vertex-only']

isotile.lattice_adjacency ¶

lattice_adjacency(
    cell: NDArray[int64],
    aspect: NDArray[int64],
    tiling_type: TilingType,
    kind: AdjacencyKind,
) -> csr_array

Adjacency of tiles given by their cells and aspects, from the table of the type.

The table does not depend on the parameters, the frame or the position of the tiling. Pairs where one tile is not in the set are dropped.

Parameters:

cell ((n, 2) array of int) –

Cell (u, v) of each tile.
aspect ((n,) array of int) –

Aspect of each tile.
tiling_type (TilingType) –

The type of the tiling; its adjacency table is used.
kind (('edge', 'vertex', 'vertex-only'), default: "edge" ) –

"edge": shared edge; "vertex": shared edge or vertex; "vertex-only": shared vertex and no shared edge.

Returns:

csr_array –

Symmetric boolean matrix of shape (n, n); row and column i are tile i.

Raises:

ValueError –

If kind is not one of the three kinds.

isotile.geometric_adjacency ¶

geometric_adjacency(
    polygons: Sequence[NDArray[float64]] | NDArray[float64],
    tol: float = 1e-06,
) -> tuple[csr_array, csr_array]

Edge and vertex-only adjacency of polygons, by counting shared vertices.

Vertices closer than tol are one vertex. Two polygons share an edge if they share 2 or more vertices and are vertex-only neighbors if they share exactly one. Only vertices are compared: a vertex that lies inside an edge of another polygon is not a shared vertex.