Parameters

Description

arc_graph returns the directed graph g1 with the nodes corresponding to the arcs of the directed graph g. g1 is defined in the following way:

- its nodes correspond to the arcs of g

- 2 nodes of the new graph are adjacent if and only if the corresponding arcs of the graph g are consecutive.

The coordinates of the nodes of g1 are given by the middle points of the corresponding edges of g.

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

Examples

//create the initial graph
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.nodes.graphics.x=[281  284  360  185  405  182  118  45];
g.nodes.graphics.y=[262  179  130  154  368  248  64  309];
//customize display
g.nodes.graphics.display='name';
g.edges.graphics.name=string(1:edge_number(g));
g.edges.graphics.display='name';
show_graph(g);

//compute the arc_graph
g1=arc_graph(g);
g1.edges.graphics.name=string(1:edge_number(g1));
g1.edges.graphics.display='name';
g1.nodes.graphics.display='name';
show_graph(g1,'new');

// merge the two graph
g1.nodes.graphics.colors(2,:)=color('red');
g1.edges.graphics.foreground(:)=color('red');
show_graph(graph_union(g,g1,%f),'new')
  
  

See Also