Re: [GRASS-user] Apply arbitrary edit to all coordinates in a vector
One solution is to export, pipe through invproj, and re-import: v.out.ascii Z layer=-1 -c format=standard output=Zproj --o rm Zrot regex="[-]\d*\.\d*\s*\d*\.\d*" while read line; do if [[ $line =~ $regex ]]; then echo $line | invproj -f "%f" +proj=ob_tran +o_proj=latlon +o_lon_p=-200 +o_lat_p=18 +lon_0=180 -m 57.295779506 >> Zrot else echo $line >> Zrot fi done < Zproj -k. On Tue, Mar 13, 2018 at 3:06 PM, Ken Mankoff wrote: > > > On Tue, Mar 13, 2018 at 1:05 PM, Ken Mankoff wrote: > >> >> >> On Tue, Mar 13, 2018 at 12:21 PM, Helmut Kudrnovsky >> wrote: >> >>> Ken Mankoff wrote >>> > Is there a way to take an arbitrary vector from >>> > GRASS and apply an arbitrary transformation to each element? v.edit >>> has a >>> > move feature, but this is not what I want. >>> > >>> >>> v.transform - Performs an affine transformation (shift, scale and >>> rotate) on >>> vector map. >>> https://grass.osgeo.org/grass74/manuals/v.transform.html >>> >>> not sure it is what you're looking for. >>> >> >> Yes that would do it just fine. Unfortunately I'm not sure how to get the >> transformation matrix that invproj uses. I'll try to figure this out... >> >> > Actually this does not work because I'm in EPSG:4326 (lon,lat) location > and there are scaling issues. I think I need to access proj directly for > all vertices... > > -k. > ___ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Apply arbitrary edit to all coordinates in a vector
On Tue, Mar 13, 2018 at 1:05 PM, Ken Mankoff wrote: > > > On Tue, Mar 13, 2018 at 12:21 PM, Helmut Kudrnovsky wrote: > >> Ken Mankoff wrote >> > Is there a way to take an arbitrary vector from >> > GRASS and apply an arbitrary transformation to each element? v.edit has >> a >> > move feature, but this is not what I want. >> > >> >> v.transform - Performs an affine transformation (shift, scale and rotate) >> on >> vector map. >> https://grass.osgeo.org/grass74/manuals/v.transform.html >> >> not sure it is what you're looking for. >> > > Yes that would do it just fine. Unfortunately I'm not sure how to get the > transformation matrix that invproj uses. I'll try to figure this out... > > Actually this does not work because I'm in EPSG:4326 (lon,lat) location and there are scaling issues. I think I need to access proj directly for all vertices... -k. ___ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Apply arbitrary edit to all coordinates in a vector
On Tue, Mar 13, 2018 at 12:21 PM, Helmut Kudrnovsky wrote: > Ken Mankoff wrote > > Is there a way to take an arbitrary vector from > > GRASS and apply an arbitrary transformation to each element? v.edit has a > > move feature, but this is not what I want. > > > > v.transform - Performs an affine transformation (shift, scale and rotate) > on > vector map. > https://grass.osgeo.org/grass74/manuals/v.transform.html > > not sure it is what you're looking for. > Yes that would do it just fine. Unfortunately I'm not sure how to get the transformation matrix that invproj uses. I'll try to figure this out... -k. ___ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Apply arbitrary edit to all coordinates in a vector
Ken Mankoff wrote > Dear GRASS list, > > I'm working with data in a rotated pole projection. I'm able to convert > any > (lon,lat) pair from its "real" coordinates to its rotated pole coordinates > by piping it through the following proj command: > > invproj -f "%f" +proj=ob_tran +o_proj=latlon +o_lon_p=-200 +o_lat_p=18 > +lon_0=180 -m 57.295779506 > > In order to maintain the integrity of the data, I'd like to keep working > in > its native coordinates. Is there a way to take an arbitrary vector from > GRASS and apply an arbitrary transformation to each element? v.edit has a > move feature, but this is not what I want. > > I think I can access all points and lines and boundaries with "v.out.ascii > Z layer=-1 -c format=standard". But if I go this route I'll need to parse > apart the output, pipe only the coordinates through the invproj command, > and then re-assemble. I hope there is an easier way. > > Thanks, v.transform - Performs an affine transformation (shift, scale and rotate) on vector map. https://grass.osgeo.org/grass74/manuals/v.transform.html not sure it is what you're looking for. - best regards Helmut -- Sent from: http://osgeo-org.1560.x6.nabble.com/Grass-Users-f3884509.html ___ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user
