[GRASS-user] Listing line vector cats and node numbers

Jarek Jasiewicz 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:

SELECT lcat AS cat, COUNT(*) AS lastnumb FROM your_new_point_table GROUP 
BY lcat;

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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