y need to make a poligon, but i make the boundary then the centroid and i dont know how to tell the program to make it a poligon… can sombody help me? thanks a lot!!
On Thu, 2008-05-29 at 09:10 +0000, Isabel Alfaro Cardozo wrote:
y need to make a poligon, but i make the boundary then the centroid
and i dont know how to tell the program to make it a poligon.. can
sombody help me? thanks a lot!!
Hello!
Some ideas:
.Use v.info on your map and see how many areas are reported? Maybe you
need to run v.clean to check for broken polygons (?).
.Be sure that your boundary is closed. You will have to "close" it
manually.
.Add a centroid and "Save & Exit"
.In your GIS-Manager uncheck all except area to see whether you have
area(s) or not
Greetings,
Nikos
y need to make a poligon, but i make the boundary then the centroid and i
dont know how to tell the program to make it a poligon.. can sombody help
me? thanks a lot!!
You probably need to enable 'snapping' within the v.digit module to make the polygon
vertices coincident. See the attached screenshot showing where to set this on the
v.digit Settings.
Once you have snapping enabled, you may still have to manually move vertices that were
digitzed prior to enabling snapping. Use the 'Move point, line, boundary, or centroid'
tool on the v.digit interface (see attached screenshot). Once you move a vertex on top
of another with this tool, the two should snap an become coincident. I usually make
the snapping parameter around a few tens of meters for projected (UTM-style) projections.
~ Eric.
(attachments)
thank you a lot, im new in grass, im learning and i cant get the poligon
area, i think the procedure is to use the boundary button, make it close
then use the centroid option and then when i save the file and check the
info it says i have a boundary and a centriod but no area, im i missing
some steps?my snapping is the same as yours
Please keep all responses on the Grass mailing list so that others may
participate/respond. Thanks...
Can you post a screenshot of your v.digit session? What happens when you manually
move two vertices together, do they snap? Can you post the output from v.info?
~ Eric.