Dear list, I have to produce shapefile for a coworker which uses ArcGIS and I've hit a problem with the writeOGR function from the rgdal package.
Here is an example: ### > library(rgdal) Loading required package: sp Geospatial Data Abstraction Library extensions to R successfully loaded Loaded GDAL runtime: GDAL 1.9.0, released 2011/12/29 Path to GDAL shared files: \\sebpriv/usagers/Ferba1/R/R-2.15.0/library/rgdal/gdal Loaded PROJ.4 runtime: Rel. 4.7.1, 23 September 2009, [PJ_VERSION: 470] Path to PROJ.4 shared files: \\sebpriv/usagers/Ferba1/R/R-2.15.0/library/rgdal/proj > sessionInfo() R version 2.15.0 (2012-03-30) Platform: i386-pc-mingw32/i386 (32-bit) locale: [1] LC_COLLATE=French_Canada.1252 LC_CTYPE=French_Canada.1252 LC_MONETARY=French_Canada.1252 LC_NUMERIC=C LC_TIME=French_Canada.1252 attached base packages: [1] stats graphics grDevices utils datasets methods base other attached packages: [1] rgdal_0.7-8 sp_0.9-98 loaded via a namespace (and not attached): [1] grid_2.15.0 lattice_0.20-6 > setwd("C:\\Documents and Settings\\ferba1\\Bureau\\test rgdal") # make a basic shape: > coo <- coordinates(cbind(runif(100,220000,300000),runif(100,5160000,5220000))) > point.shape <- > SpatialPointsDataFrame(coo,data.frame(ID=paste("point",1:100,sep="_")), + proj4string = CRS(" +proj=tmerc +lat_0=0 +lon_0=-73.5 +k=0.9999 +x_0=304800 +y_0=0 +datum=NAD83 +units=m +no_defs +ellps=GRS80 +towgs84=0,0,0")) # now if I try to write itm it works fine for the first 2 shapes: > writeOGR(point.shape,".","point_shape1", driver="ESRI Shapefile") > > writeOGR(point.shape,".","point_shape2", driver="ESRI Shapefile" ) # but then if I try to overwrite, it fails: > writeOGR(point.shape,".","point_shape1", driver="ESRI Shapefile", > overwrite_layer=T) Error in writeOGR(point.shape, ".", "point_shape1", driver = "ESRI Shapefile", : Creation of output file failed # Interestingly, it erases 2 files from point_shape1 before failing (the .prj and the .shx). # and from now on, it's impossible to create new shapefile: > writeOGR(point.shape,".","point_shape3", driver="ESRI Shapefile" ) Error in writeOGR(point.shape, ".", "point_shape3", driver = "ESRI Shapefile") : Creation of output file failed ### However, after restarting the whole session and erasing the files created, and try this new order: ### > > writeOGR(point.shape,".","point_shape1", driver="ESRI Shapefile") > > writeOGR(point.shape,".","point_shape1", driver="ESRI Shapefile", > overwrite_layer=T) > > writeOGR(point.shape,".","point_shape2", driver="ESRI Shapefile" ) > > writeOGR(point.shape,".","point_shape3", driver="ESRI Shapefile" ) > ### Everything works fine. So two questions arise: 1) why does overwrite_layer doesn't work when the order is changed, can it be fixed? 2) How to "reset" the writeOGR function after a fail as it seems once it fails, it get impossible to reuse it in the same session. After reading this post: http://stackoverflow.com/questions/6219368/problem-writing-shapefiles-with-writeogr-in-r, I think it may be some connection issue. Is there a easy way to close manually the connection after using writeOGR? Something like close.OGR.connection()? I know maptools::writeSpatialShape can also be used to write shapefile, however it doesn't write the projection information which I want. It seems to me that there is a problem with writeOGR, which is a good function so it could deserve to be fix. Thanks for your help, Bastien Ferland-Raymond, M.Sc. Stat., M.Sc. Biol. Division des orientations et projets spéciaux Direction des inventaires forestiers Ministère des Ressources naturelles et de la Faune _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo