[GRASS-user] Listing line vector cats and node numbers
jarekj at amu.edu.pl
Sat Sep 2 01:57:31 EDT 2006
CTS Dubbo - Tony Fransos napisał(a):
> I am converting from being a long time user of Arc-INFO to using GRASS.
> I have one particular need that I have not been able to solve as yet.
> For a vector line map, is there any way in GRASS to get a
> listing/table/report showing the line cats with the end node numbers?
> I have been able to get a map of these precise data using d.vect, and I
> have been able to get a list of the line cats with the coordinates of
> the nodes, but not what I really need.
> Thanks in advance
> Tony Fransos
I don't know about grass exactly but similar problem (not the same!) I
solved outside grass, using PostgreeSQL. I'm affraid that on dbf it
could not work.
I had lines with cats and its geometric parametres stored in 1 table.
Next I convert lines to points (v.to.points) I recived new table with
new cat points (cat) old cat lines (lcat) and position along (along)
Now for you: the number of last point you can recive via SQL:
CREATE TABLE new_tab AS
SELECT lcat AS cat, COUNT(*) AS lastnumb FROM your_new_point_table GROUP
You will recive number of verticles for every line, so the number of last
Next you can join the table back to your line vector with v.db.connect
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