TriangularLattice

class TriangularLattice(rows, cols, edge_parameter=1.0, onsite_parameter=0.0, boundary_condition=BoundaryCondition.OPEN)

Bases: Lattice

Triangular lattice.

Parameters:

• rows (int) – Length of the x direction.

• cols (int) – Length of the y direction.

• edge_parameter (complex | Tuple[complex, complex, complex]) – Weights on the edges in x, y and diagonal directions. This is specified as a tuple of length 3 or a single value. When it is a single value, it is interpreted as a tuple of length 3 consisting of the same values. Defaults to 1.0,

• onsite_parameter (complex) – Weight on the self-loops, which are edges connecting a node to itself. Defaults to 0.0.

• boundary_condition (BoundaryCondition) – Boundary condition for the lattice. The available boundary conditions are: BoundaryCondition.OPEN, BoundaryCondition.PERIODIC. Defaults to BoundaryCondition.OPEN.

Raises:

ValueError – Given size, edge parameter or boundary condition are invalid values.

Attributes

graph

Return a copy of the input graph.

node_indexes

Return the node indexes.

num_nodes

Return the number of nodes.

weighted_edge_list

Return a list of weighted edges.

Methods

copy()

Return a copy of the lattice.

Return type:

Lattice

draw(*, self_loop=False, style=None)

Draw the lattice.

Parameters:

• self_loop (bool) – Draw self-loops in the lattice. Defaults to False.

• style (LatticeDrawStyle | None) – Styles for rustworkx.visualization.mpl_draw. Please see https://www.rustworkx.org/apiref/rustworkx.visualization.mpl_draw.html for details.

draw_without_boundary(*, self_loop=False, style=None)

Draw the lattice with no edges between the boundaries.

Parameters:

• self_loop (bool) – Draw self-loops in the lattice. Defaults to False.

• style (LatticeDrawStyle | None) – Styles for rustworkx.visualization.mpl_draw. Please see https://www.rustworkx.org/apiref/rustworkx.visualization.mpl_draw.html for details.

classmethod from_adjacency_matrix(interaction_matrix)

Constructs a new lattice from a 2-dimensional adjacency matrix.

This method is equivalent to PyGraph.from_adjacency_matrix() or its complex counterpart when given a complex-valued matrix.

Parameters:

interaction_matrix (ndarray) – the adjacency matrix from which to build out the lattice.

Raises:

ValueError – if the provided adjacency matrix is not a 2-D square matrix.

Returns:

A new lattice based on the provided adjacency matrix.

Return type:

Lattice

classmethod from_nodes_and_edges(num_nodes, weighted_edges)

Return an instance of Lattice from the number of nodes and the list of edges.

Parameters:

• num_nodes (int) – The number of nodes.

• weighted_edges (List[Tuple[int, int, complex]]) – A list of tuples consisting of two nodes and the weight between them.

Returns:

Lattice generated from lists of nodes and edges.

Return type:

Lattice

to_adjacency_matrix(weighted=False)

Return its adjacency matrix from weighted edges. The weighted edge list is interpreted as the upper triangular matrix. Defaults to False.

Parameters:

weighted (bool) – The matrix elements are 0 or 1 when it is False. Otherwise, the weights on edges are returned as the matrix elements.

Returns:

The adjacency matrix of the input graph.

Return type:

ndarray

uniform_parameters(uniform_interaction, uniform_onsite_potential)

Returns a new lattice with uniform parameters but otherwise identical structure.

Parameters:

• uniform_interaction (complex) – the value to use for all edge weights.

• uniform_onsite_potential (complex) – the value to use for all single-vertex loop weights.

Returns:

A new lattice with identical structure but uniform parameters.

Return type:

Lattice