node_components - Find the components associated to a specific node
node_components graph_in node [component [SHOW]]
node_components finds the components associated to the node node
of the graph graph_in provided as input, and prints on output the
size of those components. The value of the third parameter component
can be set to IN, OUT, INOUT, SSC, WCC, or ALL. According
to the value of component, the program will compute the IN-component
(IN), the OUT-component (OUT), both the IN- and OUT-component
(INOUT), the strongly connected components (SCC), or the
weakly-connected component (WCC) to which node belongs. If the
third parameter is omitted or equal to ALL, then node_components
computes all the components associated to node. If SHOW is
specified as the fourth parameter, the program also shows the list of
nodes which belong to each of the required components.
- (dash), read the edge list
from STDIN.the label of the node.
the component to compute. Can be set to one of IN
(IN-component), OUT (OUT-component), INOUT (both the IN- and
the OUT-component), SSC (strongly connected component), WCC
(weakly connected component), or ALL (all the above). If
component is not set, compute all the components.
If the (optional) fourth parameter is equal to SHOW, the program
will dump on output the list of all the nodes belonging to each
component.
node_components prints on the standard output the size of the
required components, one per line, in the format:
comp_type_1: size_1
comp_type_2: size_2
.....
where comp_type_1 is the type of component (one of IN, OUT,
SCC, or WCC) and size_1 is its size, and so on. Notice that the
sizes are not sorted. If SHOW is given, the program shows the list
of nodes belonging to each component, in the format:
comp_type_1: size_1 node_1 node_2 node_3 ...
comp_type_2: size_2 node_1 node_2 node_3 ...
We can use node_components to compute the IN-component of a specific
node. For instance, the command:
$ node_components web-NotreDame.net 2711 IN
IN: 53968
$
computes the size of the IN-component of node 2711 in the graph
www_nd.net (WWW Notre Dame). This component contains 53968
nodes. Similarly:
$ node_components web-NotreDame.net 2711 OUT SHOW
OUT: 21 559 2711 2712 2713 2714 2715 2716 ... 33271 33272
$
computes and shows the OUT-component of node 2711, which contains 21 nodes, including node 2711. Finally, we can obtain the size of all the components associated to node 2711 by running:
$ node_components web-NotreDame.net 2711
IN: 53986
OUT: 21
WCC: 325729
SCC: 18
$
In this case, the IN-component of node 2711 contains 53986 nodes, the
OUT-component contains 21 nodes, the weakly connected components
contains 325729 nodes (the whole graph), and the strongly connected
component contains 18 nodes. It is also possible to show the list of
nodes belonging to each component by providing SHOW as fourth
parameter. IN this case, it is better to save the output of
node_components into a file, e.g. by using:
$ node_components web-NotreDame.net 2711 ALL SHOW > web-NotreDame.net_components_2711
components(1), strong_conn(1), largest_component(1)
V. Latora, V. Nicosia, G. Russo, "Complex Networks: Principles, Methods and Applications", Chapter 6, Cambridge University Press (2017)
V. Latora, V. Nicosia, G. Russo, "Complex Networks: Principles, Methods and Applications", Appendix 8, Cambridge University Press (2017)
(c) (c) Vincenzo 'KatolaZ' Nicosia 2009-2017 <v.nicosia@qmul.ac.uk>.