Comments for geotechrichard

Comment on R & PostGIS Together – Brief Code Snippet to get you going by geotechrichard

geotechrichard — Mon, 24 Sep 2012 15:16:54 +0000

Hi James,

If you need more than points, you could look at using rgdal to read in a table from db. create a tmp table to hold results + geometry & read in. believe you have to convert to sp object?

Cheers,

Richard

Comment on R & PostGIS Together – Brief Code Snippet to get you going by James David Smith (@TheRealJimShady)

James David Smith (@TheRealJimShady) — Fri, 21 Sep 2012 14:35:58 +0000

Hi Richard, I’m been having a play around with connecting R to my PostGIS database but have ran into issues and I wondered whether you had any tips. My main one is that R can’t read spatial columns without converting them into points. For example:

points <- dbGetQuery(con, "select the_geom FROM table")

Gives an error of:

RS-DBI driver warning: (unrecognized PostgreSQL field type geometry (id:42200) in column 0)

Is the best way to handle this by changing the query to be something like the below, or is there a better way?

points <- dbGetQuery(con, "select st_x(the_geom), st_y(the_geom) FROM table")

Thanks

James

Comment on Regional Segmentation of SPOT Mulit-spectral Ortho by geotechrichard

geotechrichard — Thu, 09 Aug 2012 14:34:18 +0000

sorry for late reply. glad it helped!

Comment on Regional Segmentation of SPOT Mulit-spectral Ortho by Daniel Messan

Daniel Messan — Thu, 14 Jun 2012 08:40:10 +0000

Very helpful, thanks.