Get filename without extension in R

Question

I have a file

ABCD.csv 

The length before the .csv is not fixed and vary to any length.

How can I extract the portion

Answer 1

basename will also remove the path leading to the file. And with this regex, any extension will be removed.

filepath <- "d:/Some Dir/ABCD.csv"
sub(pattern = "(.*)\\..*$", replacement = "\\1", basename(filepath))

# [1] "ABCD"

Or, using file_path_sans_ext as Tyler Rinker suggested:

file_path_sans_ext(basename(filepath))

# [1] "ABCD"