running an R script from another directory

Question

Here\'s an example with a couple of scripts

test.R ==>
source(\"incl.R\", chdir=TRUE)
print(\"test.R - main script\")

incl.R ==>
print(\"incl.R - included         


        

Answer 1

I am not sure that I unserstand your problem correctly. I assume that you have your scripts test.R and incl.R in the same folder and then run test.R using Rscript from some other folder. test.R should figure out where test.R (and thus incl.R) is stored and then source incl.R.

The trick is that you have to put the full path to the script test.R as an argument to your call of Rscript. It is possible to get this argument using commandArgs and then construct the path to incl.R from it:

args <- commandArgs(trailingOnly=FALSE)
file.arg <- grep("--file=",args,value=TRUE)
incl.path <- gsub("--file=(.*)test.R","\\1incl.R",file.arg)
source(incl.path,chdir=TRUE)

In your example in the question, you call the script by Rscript --vanilla ..\test.R. args will then be a character vector that contains the element "--file=../test.R". With grep I grab this element and then use gsub to obtain the path "../incl.R" from it. This path can then be used in source.