dwave_networkx.algorithms.elimination_ordering.chimera_elimination_order#

chimera_elimination_order(m, n=None, t=4, coordinates=False)[source]#

Provides a variable elimination order for a Chimera graph.

A graph defined by chimera_graph(m,n,t) has treewidth \(max(m,n)*t\). This function outputs a variable elimination order inducing a tree decomposition of that width.

Parameters:
  • m (int) – Number of rows in the Chimera lattice.

  • n (int (optional, default m)) – Number of columns in the Chimera lattice.

  • t (int (optional, default 4)) – Size of the shore within each Chimera tile.

  • (optional (coordinates bool) – If True, the elimination order is given in terms of 4-term Chimera coordinates, otherwise given in linear indices.

  • False) (default) – If True, the elimination order is given in terms of 4-term Chimera coordinates, otherwise given in linear indices.

Returns:

order – An elimination order that induces the treewidth of chimera_graph(m,n,t).

Return type:

list

Examples

>>> G = dnx.chimera_elimination_order(1, 1, 4)  # a single Chimera tile