Source code for cfpq_data.graphs.utils.edges_statistics
"""Returns statistics of graph edges."""
import logging
from collections import defaultdict
from typing import List, Any, DefaultDict
import networkx as nx
__all__ = ["get_labels_frequency", "get_sorted_labels"]
[docs]
def get_labels_frequency(graph: nx.MultiDiGraph) -> DefaultDict[Any, int]:
"""Returns a dictionary with the number of edge labels used in the graph.
Parameters
----------
graph : MultiDiGraph
Given graph.
Examples
--------
>>> from cfpq_data import *
>>> g = labeled_two_cycles_graph(1, 1, labels=("a", "b"))
>>> list(g.edges(data=True))
[(1, 0, {'label': 'a'}), (0, 1, {'label': 'a'}), (0, 2, {'label': 'b'}), (2, 0, {'label': 'b'})]
>>> labels_frequency = get_labels_frequency(g)
>>> labels_frequency
defaultdict(<class 'int'>, {'a': 2, 'b': 2})
Returns
-------
labels_frequency : DefaultDict[Any, int]
Dictionary with edge labels usage frequency.
"""
labels_frequency = defaultdict(int)
for u, v, edge_labels in graph.edges(data=True):
for key, value in edge_labels.items():
labels_frequency[value] += 1
logging.info(f"Construct {labels_frequency=} for {graph=}")
return labels_frequency
[docs]
def get_sorted_labels(
graph: nx.MultiDiGraph,
*,
reverse: bool = False,
) -> List[Any]:
"""Returns a list of edge labels sorted by the number of uses in the graph. The labels with equal number of uses are
sorted lexicographically.
Parameters
----------
graph : MultiDiGraph
Given graph.
reverse: bool
If set to True, then the labels are sorted in reverse (ascending) order.
Examples
--------
>>> from cfpq_data import *
>>> g = labeled_two_cycles_graph(42, 29)
>>> sorted_labels = get_sorted_labels(g)
>>> sorted_labels
['a', 'b']
Returns
-------
labels : List[Any]
Sorted list of graph edge labels.
"""
sorted_pairs = sorted(
get_labels_frequency(graph).items(),
key=lambda x: (-x[1], x[0]),
reverse=reverse,
)
labels = []
for label, _ in sorted_pairs:
labels.append(label)
logging.info(f"Sort edge {labels=} of {graph=}")
return labels
