import networkx as nx
from scipy.spatial import distance
from itertools import product
from .abssimcomplex import SimplicialComplex
class VietorisRipsComplex(SimplicialComplex):
def __init__(self,
points,
epsilon,
labels=None,
distfcn=distance.euclidean):
self.pts = points
self.labels = (range(len(self.pts))
if labels is None or len(labels) != len(self.pts)
else labels)
self.epsilon = epsilon
self.distfcn = distfcn
self.network = self.construct_network(self.pts,
self.labels,
self.epsilon,
self.distfcn)
self.import_simplices(map(tuple, nx.find_cliques(self.network)))
def construct_network(self, points, labels, epsilon, distfcn):
g = nx.Graph()
g.add_nodes_from(labels)
zips = zip(points, labels)
for pair in product(zips, zips):
if pair[0][1] != pair[1][1]:
dist = distfcn(pair[0][0], pair[1][0])
if dist < epsilon:
g.add_edge(pair[0][1], pair[1][1])
return g
