On Mon, 12 Apr 2010, Germ?n S?nchez Hern?ndez wrote:
Hi Carson (and list!),
I have corretly installed rgdal package in R (with some initial problems but finally working).
If I run ogrDrivers() no driver for PostgreSQL is listed (remember that the postgresql database is correctly running with the PostGIS extension, and I can connect through RODBC package):
The OGR driver will only be present if you have built OGR with PostGIS enabled. If you use the CRAN Windows 32-bit binary, or the CRAN extras OSX 32-bit or Windows 64-bit binaries, the driver is not included. To use PostGIS with OGR, install GDAL with PostGIS enabled, and check with:
$ ogrinfo --formats
Until you see PostGIS/PostgreSQL there, you will not see it inside R either, having installed rgdal from source. Using PostGIS effectively presupposes that you have some experience in installing software from source, and that your platform has the necessary build trains; these kinds of things rarely work "out of the box". The rgdal package as a binary has most commonly used drivers, and more will not be added, because they depend on libraries/DLLs external to GDAL/OGR.
Roger
name write
1 AVCBin FALSE
2 AVCE00 FALSE
3 BNA TRUE
4 CSV TRUE
5 DGN TRUE
6 DXF TRUE
7 ESRI Shapefile TRUE
8 Geoconcept TRUE
9 GeoJSON TRUE
10 GeoRSS TRUE
11 GML TRUE
12 GMT TRUE
13 GPSTrackMaker TRUE
14 GPX TRUE
15 KML TRUE
16 MapInfo File TRUE
17 Memory TRUE
18 PCIDSK FALSE
19 REC FALSE
20 S57 TRUE
21 SDTS FALSE
22 SQLite TRUE
23 TIGER TRUE
24 UK .NTF FALSE
25 VFK FALSE
26 VRT FALSE
27 XPlane FALSE
What am I missing?
Thank you!
Germ?n S?nchez
german.sanchez at esade.edu
El 08/04/2010, a las 13:17, Carson Farmer escribi?:
Hi Germ?n,
Have a look at package rgdal and the readOGR function.
Here is a link with a quick bit on using rgdal to access a postgis table:
http://wiki.intamap.org/index.php/PostGIS
Regards,
Carson
On Thu, Apr 8, 2010 at 11:21 AM, Germ?n S?nchez
<german.sanchez at ais-int.com> wrote:
Dear all,
I've working with spatial data since only a few months. I know how to
handle this kind of data in R using the sp package. I know how to load
shapes, plot them, merge their polygons, plotting labels, etc.
I have installed a postgis database and I can connect to it from R via
RODBC without problems. I can load a shape file (.shp and so) into the
database (command shp2pgsql to create the needed .sql). It creates a
table with some usual fields (area, perimeter, district, etc) and the
special one: the_geom.
Now, I want to load this data to a SpatialPolygon (or
SpatialPolygonDataFrame) object using the RODBC driver. I would like to
get the same object as if I have used the "readShapePoly" function from sp
package directly over the .shp file.
Any idea? Is there a direct solution or I have to build the polygon myself?
Thank you,
Germ?n S?nchez
german.sanchez at esade.edu