[GRASSLIST:785] Select number of features

[Sudipta Sarkar]

Hi Guys,
I have a vector map with three layers added. the output from a v.category map=parcel op=print layer=1,2,3|more looks like this:

12|1|1
24|2|2
28|3|3
34|4|4
42|5|5
42|6|6
45|7|7
247|8|8
247|9|9
443|10|10
548|11|11
749/833/834/835/836/837/838/839/840/841/842/843/844/845/846/847/848/849/850/851/852/853/854/855/856/857/
858/859/860/861/862/863|32|12
1334|12|13
1335|13|14
1337|14|15
1429|15|16
1435/1679/1680/1681/1682/1683/1684/1685/1686/1687/1688/1689/1690/1691/
1692/1693/1694/1695|18|17

where the first column gives the cat of layer 1, second column gives the cat of layer 2 and third column gives the cat of layer 3. The series of cats in the first column separated by "/" are the cats of stacked polygons in layer 1.
Now I want to do get a count of all features in layer 1 for a given cat in layer 3. As you can see from above some of the cats in layer 3 will be linked to more than one features in layer 1 so how can i get these number of features in layer 1 for each cat in layer 3.? This will help me to identify all stacked polygons.
Any help will be deeply appreciated.
Thanks and regards


Sudipta Sarkar PhD
Climate Scientist/Senior Analyst
Forest One
Ph(O): 630-250-0468
Email: ssarkar at forestone.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.osgeo.org/pipermail/grass-user/attachments/20060420/94b8f5fc/attachment.html