def fs_digraph_using_basic_properties(D, stats, options={'features': []}):
""""""
# at least one of these features needed to continue
if len([
f for f in ['degree', 'parallel_edges', 'fill']
if f in options['features']
]) == 0:
return
# feature: order
num_vertices = D.num_vertices()
log.debug('done order')
# feature: size
num_edges = D.num_edges()
log.debug('done size')
stats['n'] = num_vertices
stats['m'] = num_edges
# feature: mean_degree
if 'degree' in options['features']:
stats['mean_degree'] = float(2 * num_edges) / num_vertices
log.debug('done mean_degree')
# feature: fill_overall
if 'fill' in options['features']:
stats['fill_overall'] = float(num_edges) / (num_vertices *
num_vertices)
log.debug('done fill_overall')
if 'parallel_edges' in options['features'] or 'fill' in options['features']:
eprop = label_parallel_edges(D, mark_only=True)
PE = GraphView(D, efilt=eprop)
num_edges_PE = PE.num_edges()
stats['m_unique'] = num_edges - num_edges_PE
# feature: parallel_edges
if 'parallel_edges' in options['features']:
stats['parallel_edges'] = num_edges_PE
log.debug('done parallel_edges')
# feature: fill
if 'fill' in options['features']:
stats['fill'] = float(num_edges - num_edges_PE) / (num_vertices *
num_vertices)
log.debug('done fill')
def is_tree(t):
# to undirected
t = GraphView(t, directed=False)
# num nodes = num edges+1
if t.num_vertices() != (t.num_edges() + 1):
return False
# all nodes have degree > 0
vs = list(map(int, t.vertices()))
degs = t.degree_property_map('out').a[vs]
if np.all(degs > 0) == 0:
return False
return True