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rcsvsubsetsubstr

Stop substr at path separator?

I want to name a file according to specific section of the file path. Is it possible to have a substr stop at a path separator?

For example, I want an output file to read "worldclim.csv"

if I am extracting data from this path:"F:\Data\WorldClim\masked\Africa" I want the output file to be named: "worldclim.csv"

Here is an example: 

(file.out <- runif(4))
(path <- "F:\\Data\\WorldClim\\masked\\Africa")
(pname <- sapply(path, function(x) substr(x,start=9,stop=17)))
write.csv(file.out, paste0("F:\\Data\\extractions\\", pname, ".csv"), row.names=F)

However, I need to do this for many directories, and the sub-directories inside "Data" have different character lengths.

In short, I want "file.out" to be named after the directory that follows Data. Any ideas?

Solution

  • I guess you can simply split on \\:

    strsplit(path, '\\\\')[[1]][3]
# [1] "WorldClim"

# or

strsplit(path, '\\', fixed = TRUE)[[1]][3]
# [1] "WorldClim"

    or use regex to match 8 characters from start and then extract the pattern until the next \\:

    sub('^.{8}([^\\]+).*$', '\\1', path)
# [1] "WorldClim"