Hi Markus and list, - I'm using GRASS 6.3.cvs (2006) underQGIS (using the qgis_setup0.8.1preview3.exe installer from: http://qgis.org/uploadfiles/testbuilds/) in a Windows 2000 environment. I've installed qgis in a directory (C:\QGIS) with no spaces or path names over 8 characters - the data I downloaded is from the geographynetwork.ca website, and comes in shapefile format - Created a new mapset in GRASS (using QGIS GUI) - Added shapefile to QGIS project - import shapefile to GRASS vector using v.in.ogr using QGIS "GRASS Tools" - run v.clean as per CORINE example (v.clean input=wateroriginal output=waterclean tool=rmdupl) in GRASS shell - at this point I noticed that the attribute values are not carried through and I'm left with only "id" and "cat" - why is this, and will it cause problems later on? - run v.dissolve (v.dissolve input=waterclean output=waterdissolve) in GRASS shell, result is a non-dissolved file - I didn't specify a category, but I'm only doing a "spatial" dissolve, so is this necessary? - I also tried v.extract -d (v.extract -d input=waterclean output=waterextract) in the GRASS shell without success
Hopefully I'm missing something obvious! Any help would be appreciated. Cheers, Darren On 5/28/07, Markus Neteler <[EMAIL PROTECTED]> wrote:
Darren, could you be more specific about what you did (commands + flags/params), which GRASS version etc? I just used this method recently again with success. The v.patch step in the CORINE example is necessary for *CORINE* since you get vector tiles. If you have already a patched map, don't use it. Markus Darren Cope wrote on 05/28/2007 02:01 PM: > Hi Markus, > > I must be missing something, because this still does not seem to work. > I found another (non-GRASS) way to accomplish this, so the priority > is not very high, but I'd still like to figure out the GRASS method. > Is the v.patch step in the CORINE example necessary, or mostly just > the v.clean step with rmdupl? > > Cheers, > > Darren > > On 5/16/07, Markus Neteler <[EMAIL PROTECTED]> wrote: >> >> Hi Darren, >> >> I also stumbled over this problem, but we solved it. The trick is that >> you first have to remove the duplicated tile boundaries, then dissolve >> works. >> See example for CORINE Landcover SHAPE files: >> http://grass.itc.it/grass63/manuals/html63_user/v.dissolve.html >> >> Cheers >> Markus >> >> >> Darren Cope wrote: >> > >> > Hi all, >> > >> > I'm new to GRASS, and using it in Windows via QGIS. >> > >> > I am attempting to do a "spatial dissolve" (i.e. not dissolve on an >> > attribute, but rather just remove unnecessary tile boundaries) on a >> > file that I've imported to GRASS from a shapefile, and am so far >> > unsuccessful. The file contains waterbodies, and some of them are cut >> > in pieces by tile boundaries. I would like to remove these >> > boundaries. Can someone please help me out? I've tried combinations >> > of v.extract -d with no success, and am not sure how the "category" >> > value apply when I'm not dissolving on an attribute. >> > >> > So far my search of the archives has turned up something close, but >> > nothing that seems to fit my situation exactly. >> > >> > Cheers, >> > >> > Darren Cope >> > [EMAIL PROTECTED] >> > http://dmcope.freeshell.org ------------------ ITC -> dall'1 marzo 2007 Fondazione Bruno Kessler ITC -> since 1 March 2007 Fondazione Bruno Kessler ------------------ _______________________________________________ grassuser mailing list [email protected] http://grass.itc.it/mailman/listinfo/grassuser
-- Darren Cope [EMAIL PROTECTED] http://dmcope.freeshell.org _______________________________________________ grassuser mailing list [email protected] http://grass.itc.it/mailman/listinfo/grassuser
