Jeff Hamann <jeff.hamann <at> forestinformatics.com> writes: > > After writing some code (stupidly without checking to see if there was > code to do this already) to generate PostGIS SQL insert statements for > simple geometry (wkt), I didn't check see if there is already something > available to convert WKT strings into some R package geometry (sp?). > Does anyone have any advice, hints, code (?) for converting the > following OpenGIS strings into something useful in R:
If you are thinking of PostGIS, then readOGR() in rgdal will read them if build with the necessary driver(s). On Linux and/or OSX, the user would configure OGR to choose the external headers and libraries. On Windows, the user might choose to install rgdal from source against the FWTools DLLs, which are at: http://fwtools.maptools.org/ The PostGIS driver is described here: http://www.gdal.org/ogr/drv_pg.html There are some notes on using the driver with rgdal here: http://wiki.intamap.org/index.php/PostGIS > > POINT, MULTIPOINT, LINESTRING, MULTILINESTRING, POLYGON, MULTIPOLYGON, > GEOMETRYCOLLECTION In principle, only POINT, LINESTRING, and POLYGON (maybe MULTIPOLYGON, but handled like a shapefile, that is flattened) are supported in sp/rgdal. Please consider following up on R-sig-geo; there are possibly more eyes with relevant experience there. If the OpenGIS strings could rather be treated as GML, OGR has a driver for that too. Roger Bivand > > Jeff. > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
