Utilities¶

Helper Functions¶

Miscellaneous Helpers for NetworkX.

These are not imported into the base networkx namespace but can be accessed, for example, as

>>> import networkx
>>> networkx.utils.is_string_like('spam')
True

`is_string_like`(obj)	Check if obj is string.
`flatten`(obj[, result])	Return flattened version of (possibly nested) iterable object.
`iterable`(obj)	Return True if obj is iterable with a well-defined len().
`is_list_of_ints`(intlist)	Return True if list is a list of ints.
`make_str`(x)	Return the string representation of t.
`generate_unique_node`()	Generate a unique node label.
`default_opener`(filename)	Opens $filename$ using system’s default program.

Union-find data structure.

UnionFind.union(*objects) Find the sets containing the objects and merge them all.

Utilities for generating random numbers, random sequences, and random selections.

`create_degree_sequence`(n[, sfunction, max_tries])
`pareto_sequence`(n[, exponent])	Return sample sequence of length n from a Pareto distribution.
`powerlaw_sequence`(n[, exponent])	Return sample sequence of length n from a power law distribution.
`uniform_sequence`(n)	Return sample sequence of length n from a uniform distribution.
`cumulative_distribution`(distribution)	Return normalized cumulative distribution from discrete distribution.
`discrete_sequence`(n[, distribution, ...])	Return sample sequence of length n from a given discrete distribution or discrete cumulative distribution.
`zipf_sequence`(n[, alpha, xmin])	Return a sample sequence of length n from a Zipf distribution with exponent parameter alpha and minimum value xmin.
`zipf_rv`(alpha[, xmin, seed])	Return a random value chosen from the Zipf distribution.
`random_weighted_sample`(mapping, k)	Return k items without replacement from a weighted sample.
`weighted_choice`(mapping)	Return a single element from a weighted sample.

open_file(path_arg[, mode]) Decorator to ensure clean opening and closing of files.

Cuthill-McKee ordering of graph nodes to produce sparse matrices

`cuthill_mckee_ordering`(G[, heuristic])	Generate an ordering (permutation) of the graph nodes to make a sparse matrix.
`reverse_cuthill_mckee_ordering`(G[, heuristic])	Generate an ordering (permutation) of the graph nodes to make a sparse matrix.

reversed(*args, **kwds) A context manager for temporarily reversing a directed graph in place.