[R] regular expressions in R

jim holtman jholtman at gmail.com
Wed Dec 21 17:22:56 CET 2011


To be correct for the regular expression, it should be:

dir(pattern = "\\.(txt|doc)$")

The form

dir(pattern="*.txt")

will match 'txt' appearing anywhere in the name; this looks like the
argument you would have used to "Sys.glob" which is a UNIX style file
name match and not a regular expression.  "." matches any character
unless you escape it to mean a 'period'.

On Wed, Dec 21, 2011 at 11:11 AM, R. Michael Weylandt
<michael.weylandt at gmail.com> wrote:
> Do you wish to include .docx files as well or just .doc?
>
> Michael
>
> On Wed, Dec 21, 2011 at 10:04 AM, Alaios <alaios at yahoo.com> wrote:
>> Dear all
>> I would like to ask from dir function in R (?dir)
>> to give me only the files that end with .txt or .doc.
>>
>> The dir functions supports the use of patterns (is not that regular expressions) for doing that.
>>
>>   print(dir(i,full.names=TRUE,pattern=.....))
>>
>> Could you please help me compose such a pattern?
>>
>> B.R
>> Alex
>>        [[alternative HTML version deleted]]
>>
>>
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.



-- 
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?
Tell me what you want to do, not how you want to do it.



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