[GRASS-user] grass gis equivalent of st_subdivide

Hi,
How do I divide an area into smaller areas ( I am looking for functionality of st_subdivide in postgis).
I need to split some big areas into smaller ones (and all smaller ones should have the same attributes).
I understand that it means that underlying topology would change( It would add more boundaries).

When v.in.ogr imports a shapefile in Grass GIS, it automatically splits the overlapping areas to make them topologically correct, so I am hoping that
there is already some way to just split a topologically valid area as well…

Best,
HB

Hi HB,

Le 13 octobre 2021 22:57:21 GMT+01:00, B H <hemantbist@gmail.com> a écrit :

Hi,
How do I divide an area into smaller areas ( I am looking for functionality
of st_subdivide in postgis).
I need to split some big areas into smaller ones (and all smaller ones
should have the same attributes).
I understand that it means that underlying topology would change( It would
add more boundaries).

When v.in.ogr imports a shapefile in Grass GIS, it automatically splits the
overlapping areas to make them topologically correct, so I am hoping that
there is already some way to just split a topologically valid area as
well...

I don't think that there is any readymade module for this. You could just create a fixed grid with v.mkgrid and v.overlay it with something like this:

v.overlay ain=orig bin=grid out=subdivided operator=and olayer=0,1,0

Moritz

Hi,

Moritz Lennert <mlennert@club.worldonline.be> schrieb am Do., 14. Okt. 2021, 02:28:

Hi HB,

Le 13 octobre 2021 22:57:21 GMT+01:00, B H <hemantbist@gmail.com> a écrit :

Hi,
How do I divide an area into smaller areas ( I am looking for functionality
of st_subdivide in postgis).
I need to split some big areas into smaller ones (and all smaller ones
should have the same attributes).
I understand that it means that underlying topology would change( It would
add more boundaries).

When v.in.ogr imports a shapefile in Grass GIS, it automatically splits the
overlapping areas to make them topologically correct, so I am hoping that
there is already some way to just split a topologically valid area as
well…

I don’t think that there is any readymade module for this. You could just create a fixed grid with v.mkgrid and v.overlay it with something like this:

v.overlay ain=orig bin=grid out=subdivided operator=and olayer=0,1,0

Another option to try may be this one:

https://grass.osgeo.org/grass-stable/manuals/v.voronoi.html#skeletons-and-center-lines-of-areas

Markus