What is the best way to deal with temporary directory and workspaces while processing bigger rasters?

Question

As large workspaces have been occupied by the temporary folder, I indexed to the folder in the remote desktop referencing solutions from R-help and in my case using terraOptions this way:

terraOptions(tempdir = "/processing/tmp_terra/")

I cropped a raster (took 6 hours) and saved it as a file name LA_crop.tif to another folder with a different name. I loaded the saved raster in the new session:

myRaster <- rast(“/home/shared/om/data/rasters/LA_crop.tif”)
myPolygon <- vect(“/home/shared/om/data/polygons/PA.gpkg”)

# Now, while performing other operations like: 

r <- rasterize(myPolygon, myRaster, myPolygon$ID)

# I am getting this error:
Error: [rasterize] file does not exist: /tmp/RtmpiiUwq0/spat_jprtedxq260WQLq.tif

# Everytime I run the code, the name of tmp file in error part gets changed:
Error: [rasterize] file does not exist: /tmp/RtmpnyTR6l/spat_MpDvnvNP26auyqt.tif

sessionInfo()
# R version 4.0.3 (2020-10-10)
# Platform: x86_64-pc-linux-gnu (64-bit)
# Running under: Ubuntu 20.04 LTS

But, when I perform similar operations taking an example from here, it works fine.

library(terra)
# terra version 1.1-4
f <- system.file("ex/lux.shp", package="terra")
v <- vect(f)
f <- system.file("ex/elev.tif", package="terra")
r <- rast(f)

z <- rasterize(v, r, "NAME_1")    
zonal(r, z, mean, na.rm=TRUE)

#  zone      elevation
#1    0       403.1779
#2    1       283.8853
#3    2       316.1935

1. What am I doing wrong here? Is it because I changed the temporary directory?
2. Any further suggestions on how to deal with this problem efficiently (future reference).

Answer 1

What you refer to as "file" is in fact

"/tmp/RtmpiiUwq0/spat_jprtedxq260WQLq.tif"

That file is in a temporary folder created by R. Such folders are removed when a session ends. You state however, that you saved the file elsewhere. If that is the case, you should use that file.