[GRASS-user] v.net.salesman problem: number of cities [0]

[Marco Lechner - FOSSGIS e.V.]

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