Method add_edges_from

networkx/classes/multigraph.py:538–633

Add all the edges in ebunch_to_add. Parameters ---------- ebunch_to_add : container of edges Each edge given in the container will be added to the graph. The edges can be: - 2-tuples (u, v) or - 3-tuples (u, v, d) for

(self, ebunch_to_add, **attr)

        return key

    def add_edges_from(self, ebunch_to_add, **attr):
        """Add all the edges in ebunch_to_add.

        Parameters
        ----------
        ebunch_to_add : container of edges
            Each edge given in the container will be added to the
            graph. The edges can be:

                - 2-tuples (u, v) or
                - 3-tuples (u, v, d) for an edge data dict d, or
                - 3-tuples (u, v, k) for not iterable key k, or
                - 4-tuples (u, v, k, d) for an edge with data and key k

        attr : keyword arguments, optional
            Edge data (or labels or objects) can be assigned using
            keyword arguments.

        Returns
        -------
        A list of edge keys assigned to the edges in `ebunch`.

        See Also
        --------
        add_edge : add a single edge
        add_weighted_edges_from : convenient way to add weighted edges

        Notes
        -----
        Adding the same edge twice has no effect but any edge data
        will be updated when each duplicate edge is added.

        Edge attributes specified in an ebunch take precedence over
        attributes specified via keyword arguments.

        Default keys are generated using the method ``new_edge_key()``.
        This method can be overridden by subclassing the base class and
        providing a custom ``new_edge_key()`` method.

        When adding edges from an iterator over the graph you are changing,
        a `RuntimeError` can be raised with message:
        `RuntimeError: dictionary changed size during iteration`. This
        happens when the graph's underlying dictionary is modified during
        iteration. To avoid this error, evaluate the iterator into a separate
        object, e.g. by using `list(iterator_of_edges)`, and pass this
        object to `G.add_edges_from`.

        Examples
        --------
        >>> G = nx.Graph()  # or DiGraph, MultiGraph, MultiDiGraph, etc
        >>> G.add_edges_from([(0, 1), (1, 2)])  # using a list of edge tuples
        >>> e = zip(range(0, 3), range(1, 4))
        >>> G.add_edges_from(e)  # Add the path graph 0-1-2-3

        Associate data to edges

        >>> G.add_edges_from([(1, 2), (2, 3)], weight=3)
        >>> G.add_edges_from([(3, 4), (1, 4)], label="WN2898")