DESCRIPTION
v.net.path can find shortest path(s) on the vector network.
Costs may be either line lengths, or attributes saved in a database
table. These attributes values are taken as costs of whole segments. If read
from the table, arcs' costs may be different in both directions.
Shortest paths are written to output vector file and attached attribute table.
NOTE
If the columns 'afcol', 'abcol' and 'ncol' costs are not
specified, the length of network segments is measured and
zero costs are assumed for nodes.
When using attributes, the length of segments is not used. To get
more precise results, length should be taken indirectly into account
by attributes. For example, to get the fastest path the columns
'max_speed' and 'length' are required. The correct fastest path can then
be found by specifying afcol=length/max_speed (pg driver). If needed,
the line length can be calculated and written to the attributes table
by v.to.db.
SEE ALSO
d.path,
v.net,
v.net.alloc,
v.net.iso,
v.net.salesman,
v.net.steiner,
v.to.db
AUTHOR
Radim Blazek, ITC-Irst, Trento, Italy
Last changed: $Date$