USEPA/elevatr

Trim get_elev_raster by a shapefile

Closed this issue · 6 comments

jbenzaquen42 commented

I am trying to get elevation data for TX, and I have the shapefile. When I load the shapefile and run get_elev_raster I get this error about prj. I can not get it to work no matter what crs I input, and I'm pretty new at this, so any input would be awesome!

tex_bound <- st_read("State.shp")
tex_height <- get_elev_raster(locations = text_rast, prj = "+proj=longlat +datum=WGS84 +no_defs")

Error in sp::CRS(prj) : 
  PROJ4 argument-value pairs must begin with +: GEOGCRS["WGS 84 (with axis order normalized for visualization)",
    DATUM["World Geodetic System 1984",
        ELLIPSOID["WGS 84",6378137,298.257223563,
            LENGTHUNIT["metre",1]]],
    PRIMEM["Greenwich",0,
        ANGLEUNIT["degree",0.0174532925199433]],
    CS[ellipsoidal,2],
        AXIS["geodetic longitude (Lon)",east,
            ORDER[1],
            ANGLEUNIT["degree",0.0174532925199433,
                ID["EPSG",9122]]],
        AXIS["geodetic latitude (Lat)",north,
            ORDER[2],
            ANGLEUNIT["degree",0.0174532925199433,
                ID["EPSG",9122]]]]
jhollist commented

@BigBallerBenzie Sorry to hear you are having some issues.

First thing I see is that your shapefile is reading into tex_bound, but you are pointing to a text_rast in your get_elev_raster() call. Also, I think you can avoid using the prj, as tex_bound should have one from reading in the shapefile. Try this:

tex_height <- get_elev_raster(locations  = tex_bound, z = 5, clip = "locations")

If that works, let me know. You'll need to pick a z value that works best for your application. 5 is pretty coarse, but should run quickly enough for Texas.

jbenzaquen42 commented

@jhollist After runing this line of code, I still get the same exact error that starts with:

Error in sp::CRS(prj) : 
  PROJ4 argument-value pairs must begin with +: GEOGCRS["WGS 84 (with axis order normalized for visualization)",

Tried with a wisc shapefile and got this error:

Error in sp::CRS(prj) : 
  PROJ4 argument-value pairs must begin with +: PROJCRS["NAD83(HARN) / Wisconsin Transverse Mercator",.....
jhollist commented
jbenzaquen42 commented

After running code to replicate the error, this is what sessionInfo() gives me

R version 4.0.2 (2020-06-22)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 10 x64 (build 19041)

Matrix products: default

locale:
[1] LC_COLLATE=English_United States.1252  LC_CTYPE=English_United States.1252    LC_MONETARY=English_United States.1252
[4] LC_NUMERIC=C                           LC_TIME=English_United States.1252    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
 [1] rgdal_1.5-23     sf_0.9-7         elevatr_0.3.4    plotly_4.9.3     extrafont_0.17   scico_1.2.0      ggplot2_3.3.3   
 [8] rayshader_0.19.2 raster_3.3-13    sp_1.4-2        

loaded via a namespace (and not attached):
Error in x[["Version"]] : subscript out of bounds
In addition: Warning message:
In FUN(X[[i]], ...) :
  DESCRIPTION file of package 'testthat' is missing or broken
jhollist commented
jbenzaquen42 commented

That did it!