The data appear to be stored as an ESRI grid (adf) and I have no experience with this format.
From what I can tell this format is similar to a shp file with different files storing different things pertaining to the grid.
I'm using the raster command (raster package) to read the w001001.adf file:
What you've done is perfectly fine. The raster() function invokes the GDAL
library to do the read, via the rgdal package. It doesn't read any data at
first, so dem is just a metadata shell that raster works with - if you plot
or crop or extract that triggers the actual data read as needed.
You might also try the stars package, to keep it lazy and not read all the
data at first start with the proxy argument:
On Tue, Feb 11, 2020 at 5:44 AM Julie Lee-Yaw via R-sig-Geo <
[hidden email]> wrote:
> Hi I'm using the raster package to load a DEM from here:
> http://www.cec.org/tools-and-resources/map-files/elevation-2007 >
> The data appear to be stored as an ESRI grid (adf) and I have no
> experience with this format.
> From what I can tell this format is similar to a shp file with different
> files storing different things pertaining to the grid.
> I'm using the raster command (raster package) to read the w001001.adf file:
> The produces what looks like a raster with values. Is that all I need to
> do or should I be reading these data another way?
> [[alternative HTML version deleted]]
> R-sig-Geo mailing list
> [hidden email] > https://stat.ethz.ch/mailman/listinfo/r-sig-geo >
Software and Database Engineer
Australian Antarctic Division
e-mail: [hidden email]