"""Methods for simplicial complexes."""
from ..core import Hypergraph, SimplicialComplex
from ..exception import XGIError
from ..generators import empty_simplicial_complex
__all__ = ["from_simplex_dict", "from_max_simplices"]
[docs]def from_simplex_dict(d, create_using=None):
"""Creates a Simplicial Complex from a dictionary of simplices,
if the subfaces of existing simplices are not given in the dict
then the function adds them with integer IDs.
Parameters
----------
d : dict
A dictionary where the keys are simplex IDs and the values
are containers of nodes specifying the simplices.
create_using : SimplicialComplex constructor, optional
The simplicial complex object to add the data to, by default None
Returns
-------
SimplicialComplex object
The constructed simplicial complex object
"""
SC = empty_simplicial_complex(create_using)
SC.add_simplices_from((members, uid) for uid, members in d.items())
return SC
[docs]def from_max_simplices(SC):
"""Returns a hypergraph constructed from the
maximal simplices of the provided simplicial complex.
Parameters
----------
SC : SimplicialComplex
Returns
-------
Hypergraph
"""
if type(SC) != SimplicialComplex:
raise XGIError("The input must be a SimplicialComplex")
max_simplices = SC.edges.maximal()
H = Hypergraph()
H.add_nodes_from(SC.nodes) # to keep node order and isolated nodes
H.add_edges_from([list(SC.edges.members(e)) for e in max_simplices])
return H