hi list,
I've got a little net of ways and try to calculate a route from it. all
the crossroads and all the ends of culs-de-sac have to be reached.
according to the syntax of traveling-salesman-problem each cul-de-sac
and crossroad is a "city". I tried the following:
- import of the ways using v.in.ogr
- v.clean.break to segment the ways at crossroads
- v.net.nodes to create arcs and nodes of the net (looks o.k.)
- v.net.salesman input=net_nodes alayer=1 nlayer=0 ccats=0
output=net_salesman
to get the solution, but instead I get the following error message:
Number of cities: [0]
ERROR: Not enough cities (< 2)
although layer_0 consists of 4 nodes (two at ends of cul-de-sac and two
crossroads. In addition to that the cat-row is 0 at every node.
any ideas?
Marco
On 24/06/09 19:46, Marco Lechner - FOSSGIS e.V. wrote:
hi list,
I've got a little net of ways and try to calculate a route from it. all
the crossroads and all the ends of culs-de-sac have to be reached.
according to the syntax of traveling-salesman-problem each cul-de-sac
and crossroad is a "city". I tried the following:
- import of the ways using v.in.ogr
- v.clean.break to segment the ways at crossroads
- v.net.nodes to create arcs and nodes of the net (looks o.k.)
I guess you mean v.net operation=nodes ? What is the exact command line you use ?
- v.net.salesman input=net_nodes alayer=1 nlayer=0 ccats=0
output=net_salesman
By default, nlayer should be 2 and ccats has to list the cat values of the nodes you want to include in your salesman journey. If you just want to include all nodes, use ccats=1-9999.
to get the solution, but instead I get the following error message:
Number of cities: [0]
ERROR: Not enough cities (< 2)
although layer_0 consists of 4 nodes (two at ends of cul-de-sac and two
crossroads.
What is layer_0 and how do you see that it contains the nodes ?
In addition to that the cat-row is 0 at every node.
Again, could you tell us how you get that info ?
Moritz