Python networkx.number_weakly_connected_components() Examples

def _sanity_check(G):
    r"""
    Helper function that checks if the input graphs contains a single connected component. Raises an error if not.

    Parameters
    ----------
    G : graph
       A NetworkX graph

    Raises
    ------
    ValueError
        If the graph has more than one (weakly) connected component.
    """
    # Compute the number of connected components
    if G.is_directed():
        num_ccs = nx.number_weakly_connected_components(G)
    else:
        num_ccs = nx.number_connected_components(G)

    # Rise an error if more than one CC exists
    if num_ccs != 1:
        raise ValueError("Input graph should contain one (weakly) connected component. "
                         "This graph contains: " + str(num_ccs)) 

def list(self) -> List[Tuple[str, float]]:
        """Return a list of tuples that summarize the graph."""
        number_nodes = self.graph.number_of_nodes()
        return [
            ('Name', self.graph.name),
            ('Version', self.graph.version),
            ('Number of Nodes', number_nodes),
            ('Number of Namespaces', len(self.graph.count.namespaces())),
            ('Number of Edges', self.graph.number_of_edges()),
            ('Number of Annotations', len(self.graph.count.annotations())),
            ('Number of Citations', self.graph.number_of_citations()),
            ('Number of Authors', self.graph.number_of_authors()),
            ('Network Density', '{:.2E}'.format(nx.density(self.graph))),
            ('Number of Components', nx.number_weakly_connected_components(self.graph)),
            ('Number of Warnings', self.graph.number_of_warnings()),
        ] 

def component_nb(self) -> int:
        """Return the number of independent components that this
        DAGCircuit can be split into."""
        return nx.number_weakly_connected_components(self.graph) 

def test_number_weakly_connected_components(self):
        for G, C in self.gc:
            U = G.to_undirected()
            w = nx.number_weakly_connected_components(G)
            c = nx.number_connected_components(U)
            assert_equal(w, c) 

def test_connected_raise(self):
        G=nx.Graph()
        assert_raises(NetworkXNotImplemented,nx.weakly_connected_components, G)
        assert_raises(NetworkXNotImplemented,nx.number_weakly_connected_components, G)
        assert_raises(NetworkXNotImplemented,nx.weakly_connected_component_subgraphs, G)
        assert_raises(NetworkXNotImplemented,nx.is_weakly_connected, G) 

def test_number_weakly_connected_components(self):
        for G, C in self.gc:
            U = G.to_undirected()
            w = nx.number_weakly_connected_components(G)
            c = nx.number_connected_components(U)
            assert_equal(w, c)

    # deprecated 

def test_null_graph(self):
        G = nx.DiGraph()
        assert_equal(list(nx.weakly_connected_components(G)), [])
        assert_equal(nx.number_weakly_connected_components(G), 0)
        assert_raises(nx.NetworkXPointlessConcept, nx.is_weakly_connected, G) 

def test_connected_raise(self):
        G = nx.Graph()
        assert_raises(NetworkXNotImplemented, nx.weakly_connected_components, G)
        assert_raises(NetworkXNotImplemented, nx.number_weakly_connected_components, G)
        assert_raises(NetworkXNotImplemented, nx.is_weakly_connected, G)
        # deprecated
        assert_raises(NetworkXNotImplemented, nx.weakly_connected_component_subgraphs, G) 

def test_number_weakly_connected_components(self):
        for G, C in self.gc:
            U = G.to_undirected()
            w = nx.number_weakly_connected_components(G)
            c = nx.number_connected_components(U)
            assert_equal(w, c) 

def test_connected_raise(self):
        G=nx.Graph()
        assert_raises(NetworkXNotImplemented,nx.weakly_connected_components, G)
        assert_raises(NetworkXNotImplemented,nx.number_weakly_connected_components, G)
        assert_raises(NetworkXNotImplemented,nx.weakly_connected_component_subgraphs, G)
        assert_raises(NetworkXNotImplemented,nx.is_weakly_connected, G)