graph_power - kth power of a directed 1-graph

Calling Sequence

g1 = graph_power(g,k)

Parameters

• g : graph list of the graph
• k : integer
• g1 : graph list of the new graph

Description

graph_power computes the directed graph g1 which is the kth power of directed 1-graph g. There is an arc between two nodes in g1 if there exists a path between these nodes of length at most k in g. graph_power(g,1) is graph g.

If such a graph does not exist, an empty vector is returned.

Examples

ta=[1 1 2 4 4 5 6 7 2 3 5 1];
he=[2 6 3 6 7 8 8 8 4 7 3 5];
g=make_graph('foo',1,8,ta,he);
g('node_x')=[285  284  335  160  405  189  118  45];
g('node_y')=[266  179   83  176  368  252  64  309];
show_graph(g);
g1=graph_power(g,2);
show_graph(g1,'new');