hi,
After executing the following steps for shortest path in grass i get below error:
echo "update roads set travelcost=5 where cat=1" | db.execute
echo "update roads set travelcost=20 where cat=2" | db.execute
echo "update roads set travelcost=40 where cat=3" | db.execute
echo "update roads set travelcost=60 where cat=4" | db.execute
echo "update roads set travelcost=80 where cat=5" | db.execute
echo "select * from roads" | db.select
Then we can run the 'd.path' with our assigned travel costs:
d.path map=roads afcol=travelcost abcol=travelcost
error:Building graph:
ERROR: Column type not supported
Can anyone help me out with this
ec.jkd,
note: the new list address is <grass-user@lists.osgeo.org>.
On Jan 2, 2008 6:57 AM, <ec.jkd@tpcsed.com> wrote:
hi,
After executing the following steps for shortest path in grass i get below error:
echo "update roads set travelcost=5 where cat=1" | db.execute
echo "update roads set travelcost=20 where cat=2" | db.execute
echo "update roads set travelcost=40 where cat=3" | db.execute
echo "update roads set travelcost=60 where cat=4" | db.execute
echo "update roads set travelcost=80 where cat=5" | db.execute
echo "select * from roads" | db.select
Then we can run the 'd.path' with our assigned travel costs:
d.path map=roads afcol=travelcost abcol=travelcost
error:Building graph:
ERROR: Column type not supported
what does
v.info -c roads
say? Which GRASS version do you use?
Markus
PS: please use a reasonable email subject instead of "grass"