Scilab function

add_edge - adds an edge or an arc between two nodes

### Calling Sequence

  `g1 = add_edge(i,j,g)`

### Parameters

- `i` : integer, number of start node
- `j` : integer, number of end node
- `g` : graph list
- `g1` : graph list of the new graph with the added edge

### Description

`add_edge` returns the graph `g1` with a new edge from node number `i` to node number `j`. If the graph is directed, the edge is an arc. The number of edges plus 1 is taken as the name of the new edge.

### Examples

    ta=[1 1 2 2 2 3 4 5 5 7 8 8 9 10 10 10 11 12 13 13 13 14 15 16 16 17 17];
    he=[2 10 3 5 7 4 2 4 6 8 6 9 7 7 11 15 12 13 9 10 14 11 16 1 17 14 15];
    g=make_graph('foo',1,17,ta,he);
    g('node_x')=[283 163 63 57 164 164 273 271 339 384 504 513 439 623 631 757 642];
    g('node_y')=[59 133 223 318 227 319 221 324 432 141 209 319 428 443 187 151 301];
    show_graph(g);
    g=add_edge(1,7,g);
    g('edge_color')=[ones(ta) 11];
    show_graph(g);

### See Also

`add_node` `delete_arcs` `delete_nodes`