Create a graph.
[g]=NARVAL_G_MakeGraph(name,n,tail,head,node_x,node_y)
graph name.
graph size.
links tail vector.
links head vector.
vector of nodes x-coordinates.
vector of nodes y-coordinates.
network graph.
NARVAL_G_MakeGraph creates the graph g defined by n nodes with x-coordinates node_x and y-coordinates node_y. The starting (respectivelly finishing) node of each link is stored in head (respectivelly tail).