python-igraph API reference

module documentation

Low-level Python interface for the igraph library. Should not be used directly.

Class	`ARPACKOptions`	Class representing the parameters of the ARPACK module.
Class	`BFSIter`	igraph BFS iterator object
Class	`DFSIter`	igraph DFS iterator object
Class	`Edge`	Class representing a single edge in a graph.
Class	`EdgeSeq`	Low-level representation of an edge sequence.
Class	`GraphBase`	Low-level representation of a graph.
Class	`InternalError`	Undocumented
Class	`Vertex`	Class representing a single vertex in a graph.
Class	`VertexSeq`	Low-level representation of a vertex sequence.
Function	`community_to_membership`	Undocumented
Function	`convex_hull`	Calculates the convex hull of a given point set.
Function	`is_degree_sequence`	Deprecated since 0.9 in favour of `is_graphical()`.
Function	`is_graphical`	Returns whether a list of degrees can be a degree sequence of some graph, with or without multiple and loop edges, depending on the allowed edge types in the remaining arguments.
Function	`is_graphical_degree_sequence`	Deprecated since 0.9 in favour of `is_graphical()`.
Function	`set_progress_handler`	Sets the handler to be called when igraph is performing a long operation.
Function	`set_random_number_generator`	Sets the random number generator used by igraph.
Function	`set_status_handler`	Sets the handler to be called when igraph tries to display a status message.
Function	`_compare_communities`	Undocumented
Function	`_disjoint_union`	Undocumented
Function	`_intersection`	Undocumented
Function	`_power_law_fit`	Undocumented
Function	`_split_join_distance`	Undocumented
Function	`_union`	Undocumented

def community_to_membership(merges, nodes, steps, return_csize=False): ¶

Undocumented

def convex_hull(vs, coords=False): ¶

Calculates the convex hull of a given point set.

Parameters
vs	the point set as a list of lists
coords	if `True`, the function returns the coordinates of the corners of the convex hull polygon, otherwise returns the corner indices.
Returns
either the hull's corner coordinates or the point indices corresponding to them, depending on the `coords` parameter.

def is_degree_sequence(out_deg, in_deg=None): ¶

Deprecated since 0.9 in favour of is_graphical().

Returns whether a list of degrees can be a degree sequence of some graph.

Note that it is not required for the graph to be simple; in other words, this function may return True for degree sequences that can be realized using one or more multiple or loop edges only.

In particular, this function checks whether

all the degrees are non-negative
for undirected graphs, the sum of degrees are even
for directed graphs, the two degree sequences are of the same length and equal sums

Parameters
out_deg	the list of degrees. For directed graphs, this list must contain the out-degrees of the vertices.
in_deg	the list of in-degrees for directed graphs. This parameter must be `None` for undirected graphs.
Returns
`True` if there exists some graph that can realize the given degree sequence, `False` otherwise.

def is_graphical(out_deg, in_deg=None, loops=False, multiple=False): ¶

Returns whether a list of degrees can be a degree sequence of some graph, with or without multiple and loop edges, depending on the allowed edge types in the remaining arguments.

Parameters
out_deg	the list of degrees. For directed graphs, this list must contain the out-degrees of the vertices.
in_deg	the list of in-degrees for directed graphs. This parameter must be `None` for undirected graphs.
loops	whether loop edges are allowed.
multiple	whether multiple edges are allowed.
Returns
`True` if there exists some graph that can realize the given degree sequence with the given edge types, `False` otherwise.

def is_graphical_degree_sequence(out_deg, in_deg=None): ¶

Deprecated since 0.9 in favour of is_graphical().

Returns whether a list of degrees can be a degree sequence of some simple graph.

Note that it is required for the graph to be simple; in other words, this function will return False for degree sequences that cannot be realized without using one or more multiple or loop edges.

Parameters
out_deg	the list of degrees. For directed graphs, this list must contain the out-degrees of the vertices.
in_deg	the list of in-degrees for directed graphs. This parameter must be `None` for undirected graphs.
Returns
`True` if there exists some simple graph that can realize the given degree sequence, `False` otherwise.

def set_progress_handler(handler): ¶

Sets the handler to be called when igraph is performing a long operation.

Parameters
handler	the progress handler function. It must accept two arguments, the first is the message informing the user about what igraph is doing right now, the second is the actual progress information (a percentage).

def set_random_number_generator(generator): ¶

Sets the random number generator used by igraph.

Parameters

generator the generator to be used. It must be a Python object with at least three attributes: random, randint and gauss. Each of them must be callable and their signature and behaviour must be identical to random.random, random.randint and random.gauss. By default, igraph uses the random module for random number generation, but you can supply your alternative implementation here. If the given generator is None, igraph reverts to the default Mersenne twister generator implemented in the C layer, which might be slightly faster than calling back to Python for random numbers, but you cannot set its seed or save its state.

def set_status_handler(handler): ¶

Sets the handler to be called when igraph tries to display a status message.

This is used to communicate the progress of some calculations where no reasonable progress percentage can be given (so it is not possible to use the progress handler).

Parameters
handler	the status handler function. It must accept a single argument, the message that informs the user about what igraph is doing right now.

def _compare_communities(comm1, comm2, method='vi'): ¶

Undocumented

def _disjoint_union(graphs): ¶

Undocumented

def _intersection(graphs, edgemaps): ¶

Undocumented

def _power_law_fit(data, xmin=-1, force_continuous=False): ¶

Undocumented

def _split_join_distance(comm1, comm2): ¶

Undocumented

def _union(graphs, edgemaps): ¶

Undocumented

python-igraph API reference

igraph._igraph

`igraph._igraph`