A watershed polygon has 10 boundaries, 1 area, 1 centroid, and 1 island. The data table always connects to the boundaries, showing associated attributes of the 10 individual lines. How can a similar table/layer be created that houses the data of the centroid and area?
···
Damon Grabow
NDSWC
On Fri, Oct 28, 2016 at 2:59 PM, Grabow, Damon M. <dmgrabow@nd.gov> wrote:
A watershed polygon has 10 boundaries, 1 area, 1 centroid, and 1 island.
The data table always connects to the boundaries, showing associated
attributes of the 10 individual lines. How can a similar table/layer be
created that houses the data of the centroid and area?
First check with v.category option=report if the centroid has a
category in any layer.
If yes, and an attribute table for that layer does not exist
(v.db.connect -p), create a table for that layer with v.db.addtable.
If the centroid does not have a category in a separate layer, create one with
v.category option=add type=centroid layer=X
with X being a layer number not present in the output of v.category
option=report
Now create a table for layer X with v.db.addtable and you can upload
area/centroid attributes.
HTH,
Markus M
Damon Grabow
NDSWC
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