Re: [GRASS-user] Change column data format from double precision to integer
On Tue, 5 Oct 2021, Micha Silver wrote: AFAIK coordinates in GRASS (including the z coord) are always DOUBLE. The v.in.ascii function reads the x,y,z columns as DOUBLE. Micha, How interesting! In this project the depths are in integers but display as double # However, no database connection defined: Yes, I noticed this, too. The shape files for the same points, imported with v.in.ogr, do come with a database table. I was going to provide a couple of samples and ask about this but you've answered my question. # Now add a new INTEGER column v.db.addcolumn p1 column="z_int INTEGER" v.db.update p1 column=z_int query_col="CAST(elev as INTEGER)" I think that is what you wanted. Yep. That it is. Saves my time creating examples to get this same knowledge. Thanks, Rich ___ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Change column data format from double precision to integer
Hi Rich On 10/5/21 7:59 PM, Rich Shepard wrote: A vector map's database table has a column named z_int and data type of double precision as presented in the map's attribute table. It was defined as an int in the v.in.ascii command. How do I change the data type to int? AFAIK coordinates in GRASS (including the z coord) are always DOUBLE. The v.in.ascii function reads the x,y,z columns as DOUBLE. If you declare the columns parameter in v.in.ascii, these attribute columns are created as DOUBLE. I checked the OGC specs for vector data and did not find any mention that coordinates should be DOUBLE, but that's usually the case in most GIS, to the best of my knowledge. Having said that, you can create a new attribute column, and populate it with integer values from the z coordinate, with the CAST sqlite3 function. Consider: echo "1,1,1" | v.in.ascii -z input=- output=p1 separator=comma x=1 y=2 z=3 v.report p1 option=coor cat|x|y|z 1|1|1|1 # However, no database connection defined: v.info -c p1 ERROR: Database connection for map is not defined in DB file # v.to.db creates new columns as DOUBLE v.to.db p1 option=coor column="east,north,elev" v.info -c p1 Displaying column types/names for database connection of layer <1>: INTEGER|cat DOUBLE PRECISION|east DOUBLE PRECISION|north DOUBLE PRECISION|elev # Now add a new INTEGER column v.db.addcolumn p1 column="z_int INTEGER" v.db.update p1 column=z_int query_col="CAST(elev as INTEGER)" v.info -c p1 Displaying column types/names for database connection of layer <1>: INTEGER|cat DOUBLE PRECISION|east DOUBLE PRECISION|north DOUBLE PRECISION|elev INTEGER|z_int I think that is what you wanted. The only option offered in that window is to delete a column by right-clicking on it. I assume there's a way within GRASS of changing the data type. TIA, Rich ___ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user -- Micha Silver Ben Gurion Univ. Sde Boker, Remote Sensing Lab cell: +972-523-665918 ___ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] city gis data
On Tue, 5 Oct 2021, Janet Choate wrote: This may seem a ridiculous question - Janet, Nah, it isn't. Can anyone tell me where I can obtain simple city boundary gis data? I need city boundary gis data for cities in Santa Barbara County that I can download and import into GRASS. Try these: https://www.santabarbaraca.gov › services › maps › default.asp https://www.countyofsb.org › mapping.sbc https://www.countyoffice.org › santa-barbara-ca-gis-maps https://www.sbcag.org › gisportal.html All found with the duckduckgo search term, 'santa barbara city gis data' HTH, Rich ___ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user
[GRASS-user] city gis data
Hi - This may seem a ridiculous question - Can anyone tell me where I can obtain simple city boundary gis data? I need city boundary gis data for cities in Santa Barbara County that I can download and import into GRASS. thank you, Janet -- Tague Team Lab Manager 1005 Bren Hall UCSB, Santa Barbara, CA. ___ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user
[GRASS-user] Change column data format from double precision to integer
A vector map's database table has a column named z_int and data type of double precision as presented in the map's attribute table. It was defined as an int in the v.in.ascii command. How do I change the data type to int? The only option offered in that window is to delete a column by right-clicking on it. I assume there's a way within GRASS of changing the data type. TIA, Rich ___ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user
