[R] Default Argument Passing in Script

[Sebastian P. Luque]

On Wed, 11 Jun 2008 21:01:54 +0800,
"Gundala Viswanath" <gundalav at gmail.com> wrote:

> Hi all, Currently I run R script with arguments the following ways

> $ R --vanilla < myscript.R ARGUMENT1

I don't think that call could possibly recognize ARGUMENT1 in
myscript.R, according to the docs.


> And in my script it is encoded as:

> __BEGIN__ args<-commandArgs() do_sth(args[3])

> My question is that is there a way to set a default argument inside
> the R script?

> In Perl analogically would be:

> my $param = $ARGV[0] || "default_argument";

> I am wondering how can this be done in R.

For scripting, you might want to look at littler (my favorite,
http://dirk.eddelbuettel.com/code/littler.html) or (the built-in)
Rscript.  Combined with the getopt package, this lets you call/pipe
stuff in and out of R with the same ease as any other Unix tool.


-- 
Seb