In that case I'm surprised. R is generally pretty solid about interactions with the OS. I may try to reproduce this on my Mac, though probably not today or tomorrow. If I have the same failure, the next step will probably be to contact the rgdal author(s).
-Don -- Don MacQueen Lawrence Livermore National Laboratory 7000 East Ave., L-627 Livermore, CA 94550 925-423-1062 On 3/6/17, 11:48 AM, "D G. Rossiter" <d.g.rossi...@cornell.edu> wrote: Good idea. From the shell, ogrInfo correctly reads the shapefile: $ ogrInfo /Volumes/DRENTHE/ds/NEweather/ gdd50_7100j | more INFO: Open of `/Volumes/DRENTHE/ds/NEweather/' using driver `ESRI Shapefile' successful. Layer name: gdd50_7100j Geometry: Point Feature Count: 5556 Extent: (-177.350000, -14.330000) - (174.100000, 71.280000) Layer SRS WKT: GEOGCS["GCS_North_American_1927", DATUM["North_American_Datum_1927", SPHEROID["Clarke_1866",6378206.4,294.9786982]], PRIMEM["Greenwich",0.0], UNIT["Degree",0.0174532925199433]] STATION_ID: Integer (6.0) STATE: String (2.0) STATION_NA: String (24.0) etc. This is indeed an MS-DOS USB device (which came from a meeting at the Drenthe (NL) provincial enviromental bureau, hence the volume name): $ mount | grep DRENTHE /dev/disk3s1 on /Volumes/DRENTHE (msdos, local, nodev, nosuid, noowners) From R comes the failure with readOGR: > usa <- readOGR(dsn="/Volumes/DRENTHE/ds/NEweather/", layer=“gdd50_7100”) Error in ogrInfo(dsn = dsn, layer = layer, encoding = encoding, use_iconv = use_iconv, : Cannot open data source D G (David) Rossiter Section of Soil & Crop Sciences Cornell University http://www.css.cornell.edu/faculty/dgr2/ > On 06 Mar 2017, at 12:56, MacQueen, Don <macque...@llnl.gov> wrote: > > It would be informative to try ogrInfo from the shell prompt (i.e., outside of R) to find out if this is an R problem or an ogrInfo problem. > > -Don > > -- > Don MacQueen > > Lawrence Livermore National Laboratory > 7000 East Ave., L-627 > Livermore, CA 94550 > 925-423-1062 > > > On 3/4/17, 3:40 AM, "R-SIG-Mac on behalf of D G. Rossiter" <r-sig-mac-boun...@r-project.org on behalf of d.g.rossi...@cornell.edu> wrote: > > Thanks to Ken Beath, this indeed was the problem. I tested by formatting a USB drive to Mac format with Disk Info, copying the shapefiles onto it, and then reading with readOGR(). > > Problem solved, although the Mac-formatted USB drive could not be used to transfer files to and from Windows machines. > > D G (David) Rossiter > Section of Soil & Crop Sciences > Cornell University > http://www.css.cornell.edu/faculty/dgr2/ > > > 1. Re: Mac-only problem using readOGR(), which uses ogrInfo(), > to read a shapefile from a directory on a USB pen drive (Ken Beath) > > From: Ken Beath <k...@kjbeath.com.au<mailto:k...@kjbeath.com.au>> > Subject: Re: [R-SIG-Mac] Mac-only problem using readOGR(), which uses ogrInfo(), to read a shapefile from a directory on a USB pen drive > Date: 3 March 2017 at 20:28:33 GMT-5 > To: "D G. Rossiter" <d.g.rossi...@cornell.edu<mailto:d.g.rossi...@cornell.edu>> > Cc: "r-sig-mac@r-project.org<mailto:r-sig-mac@r-project.org>" <r-sig-mac@r-project.org<mailto:r-sig-mac@r-project.org>> > > > My thought is that it might be that USB drives are usually MSDOS formatted. Usually not a problem but rgdal works with directories. Formatting in a Mac with Disk Utility might be a work-around, with the limitation that the USB will only work in Macs. > > I would also try verbose=TRUE which may give more information. > > In the absence of other ideas contacting the package author can help. > > Ken > > On 4 Mar 2017, at 3:32 am, D G. Rossiter <d.g.rossi...@cornell.edu<mailto:d.g.rossi...@cornell.edu>> wrote: > > I ran across a Mac-only problem using readOGR(), which uses ogrInfo(), to read a shapefile from a directory on a USB pen drive. I tested the behaviour on a Windows 10 machine and did not get the problem. > > Trying to read from the USB drive, with relative and full paths: > > setwd("/Volumes/ISPRS/“) # this is my connected USB drive > list.files() > [1] "map7100.dbf" "map7100.prj" > [3] "map7100.sbn" "map7100.sbx" > [5] "map7100.shp" "map7100.shp.xml" > [7] "map7100.shx" > file.exists("map7100.shp") > [1] TRUE > usa <- readOGR(dsn=".", layer="map7100") > Error in ogrInfo(dsn = dsn, layer = layer, encoding = encoding, use_iconv = use_iconv, : > Cannot open data source > usa <- readOGR(dsn="/Volumes/ISPRS", layer="map7100") > Error in ogrInfo(dsn = dsn, layer = layer, encoding = encoding, use_iconv = use_iconv, : > Cannot open data source > > But, readOGR reads the shapefile correctly if it’s located on the Mac’s internal drive: > > setwd("/Users/rossiter/data/edu/dgeostats/ex") > file.exists("./ds/NEweather/map7100.shp") > [1] TRUE > usa <- readOGR(dsn="./ds/NEweather", layer="map7100") > OGR data source with driver: ESRI Shapefile > Source: "./ds/NEweather", layer: "map7100" > with 7926 features > It has 19 fields > > All packages are up to date. Here is the sessionInfo(): > > R version 3.3.2 (2016-10-31) > Platform: x86_64-apple-darwin13.4.0 (64-bit) > Running under: OS X El Capitan 10.11.6 > > locale: > [1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8 > > attached base packages: > [1] stats graphics grDevices utils datasets methods base > > other attached packages: > [1] ggplot2_2.2.1 sf_0.3-4 maptools_0.9-1 rgdal_1.2-5 > [5] sp_1.2-4 gstat_1.1-4 > > loaded via a namespace (and not attached): > [1] Rcpp_0.12.9 plyr_1.8.4 xts_0.9-7 tools_3.3.2 > [5] digest_0.6.12 evaluate_0.10 tibble_1.2 gtable_0.2.0 > [9] lattice_0.20-34 DBI_0.5-1 yaml_2.1.14 stringr_1.2.0 > [13] knitr_1.15.1 rprojroot_1.2 grid_3.3.2 spacetime_1.2-0 > [17] foreign_0.8-67 rmarkdown_1.3 udunits2_0.13 magrittr_1.5 > [21] backports_1.0.5 scales_0.4.1 intervals_0.15.1 htmltools_0.3.5 > [25] units_0.4-2 rsconnect_0.7 assertthat_0.1 colorspace_1.3-2 > [29] labeling_0.3 stringi_1.1.2 lazyeval_0.2.0 munsell_0.4.3 > [33] FNN_1.1 zoo_1.7-14 > > This is a problem because several of my students have OS/X machines and like to work from USB-connected external drives. > > D G (David) Rossiter > Section of Soil & Crop Sciences > Cornell University > http://www.css.cornell.edu/faculty/dgr2/ > > _______________________________________________ > R-SIG-Mac mailing list > R-SIG-Mac@r-project.org > https://stat.ethz.ch/mailman/listinfo/r-sig-mac > > > > > _______________________________________________ > R-SIG-Mac mailing list > R-SIG-Mac@r-project.org<mailto:R-SIG-Mac@r-project.org> > https://stat.ethz.ch/mailman/listinfo/r-sig-mac > > > [[alternative HTML version deleted]] > > _______________________________________________ > R-SIG-Mac mailing list > R-SIG-Mac@r-project.org > https://stat.ethz.ch/mailman/listinfo/r-sig-mac > _______________________________________________ R-SIG-Mac mailing list R-SIG-Mac@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-mac