Method remove_node

networkx/classes/digraph.py:579–620

Remove node n. Removes the node n and all adjacent edges. Attempting to remove a nonexistent node will raise an exception. Parameters ---------- n : node A node in the graph Raises ------ NetworkXError If n is n

(self, n)

        nx._clear_cache(self)

    def remove_node(self, n):
        """Remove node n.

        Removes the node n and all adjacent edges.
        Attempting to remove a nonexistent node will raise an exception.

        Parameters
        ----------
        n : node
           A node in the graph

        Raises
        ------
        NetworkXError
           If n is not in the graph.

        See Also
        --------
        remove_nodes_from

        Examples
        --------
        >>> G = nx.path_graph(3)  # or DiGraph, MultiGraph, MultiDiGraph, etc
        >>> list(G.edges)
        [(0, 1), (1, 2)]
        >>> G.remove_node(1)
        >>> list(G.edges)
        []

        """
        try:
            nbrs = self._succ[n]
            del self._node[n]
        except KeyError as err:  # NetworkXError if n not in self
            raise NetworkXError(f"The node {n} is not in the digraph.") from err
        for u in nbrs:
            del self._pred[u][n]  # remove all edges n-u in digraph
        del self._succ[n]  # remove node from succ
        for u in self._pred[n]:
            del self._succ[u][n]  # remove all edges n-u in digraph
        del self._pred[n]  # remove node from pred
        nx._clear_cache(self)

    def remove_nodes_from(self, nodes):
        """Remove multiple nodes.