[R] regexpr and portability issue

[Marco Blanchette]

Dear all--

I am still forging my first arms with R and I am fighting with regexpr() as
well as portability between unix and windoz. I need to extract barcodes from
filenames (which are located between a double and single underscore) as well
as the directory where the filename is residing. Here is the solution I came
to:

aFileName <- 
"/Users/marco/Desktop/diagnosticAnalysis/test/MA__251329410021_S01_A01.txt"
t <- regexpr("__\\d*_",aFileName, perl=T)
t.dir <- regexpr("^.*/", aFileName, perl=T)
base.name <- substr(aFileName, t+2, t-2 + attr(t,"match.length"))
base.dir <- substr(aFileName, t.dir, attr(t.dir,"match.length"))

My questions are:
1) Is there a more elegant way to deal with regular expressions (read here:
more easier, more like perl style).
2) I have a portability problem when I extract the base.dir Windoz is using
'\' instead of '/' to separate directories.

Any suggestions/comments

Many Tx

Marco Blanchette, Ph.D.

mblanche at uclink.berkeley.edu

Donald C. Rio's lab
Department of Molecular and Cell Biology
16 Barker Hall
University of California
Berkeley, CA 94720-3204

Tel: (510) 642-1084
Cell: (510) 847-0996
Fax: (510) 642-6062