[R] convert opengis wkt to geometry?
Roger.Bivand at nhh.no
Tue Dec 16 14:07:58 CET 2008
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:
The PostGIS driver is described here:
There are some notes on using the driver with rgdal here:
> POINT, MULTIPOINT, LINESTRING, MULTILINESTRING, POLYGON, MULTIPOLYGON,
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
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