Hi everybody,
I would like to get the nodes of a grid, I have managed to get the nodes, but do not understand how to remove duplicate points. After running "v.clean […] tool=rmdpl " I get the right number of points, however, in the database the number of features continues to be the same as before v.clean.
The manual of v.clean says:
"rmdupl: remove duplicate geometry features (pay attention to categories!)"
Does that means that v.clean preserves features with different cat numbers?, and that one feature can have more than one attribute assigned in a single table?
Thank you very much
Daniel
Ex.
In nc_spm_08
g.region rast=lsat5_1987_10
v.mkgrid grid=4,4 map=grid44
v.to.lines input=grid44 output=grid44lines
v.to.points input=grid44lines output=grid44points use=node
v.info -t grid44points
nodes=0
points=80
…
v.clean input=grid44points output=grid44pointsclean tool=rmdupl
v.info -t grid44pointsclean
nodes=0
points=25
…
primitives=25
g.gui.dbmgr grid44pointsclean2
On Thu, Jul 7, 2016 at 7:32 PM, Daniel Torres <nobeeakon@gmail.com> wrote:
Hi everybody,
I would like to get the nodes of a grid, I have managed to get the nodes,
but do not understand how to remove duplicate points. After running "v.clean
[...] tool=rmdpl " I get the right number of points, however, in the
database the number of features continues to be the same as before v.clean.
The manual of v.clean says:
"rmdupl: remove duplicate geometry features (pay attention to categories!)"
Does that means that v.clean preserves features with different cat numbers?,
No, features with identical coordinates but different categories are
merged into one feature with multiple categories.
and that one feature can have more than one attribute assigned in a single
table?
Yes. If you don't need the categories, you can delete them with
v.category and afterwards add one single unique category to each
feature with v.category. The link to attributes gets lost of course.
HTH,
Markus M
Thank you very much
Daniel
Ex.
# In nc_spm_08
g.region rast=lsat5_1987_10
v.mkgrid grid=4,4 map=grid44
v.to.lines input=grid44 output=grid44lines
v.to.points input=grid44lines output=grid44points use=node
v.info -t grid44points
nodes=0
points=80
....
v.clean input=grid44points output=grid44pointsclean tool=rmdupl
v.info -t grid44pointsclean
nodes=0
points=25
...
primitives=25
g.gui.dbmgr grid44pointsclean2
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