R help - Jul 2010 - Batch files process and String parsing

Here are what i am going to accomplish:

I have 400 files named as xxx.txt. the content of the file looks like the
following:

    name    count

1. aaa     100
2. bbb    2000
3. ccc    300
4. ddd   3000

........
more that 1000 rows in each files.

these are the areas i need help:
1. how can i only read in the files with the string patterns ggg or fff as
part of the file names?
  for instance, I only need the file names with the ggg or fff in it
     xxxxx_ggg_yyyyy_1.txt
     yyyy_fff_yyyy_xxx.txt

    i don't need to read in the files, such as xxxx_aaa_yyyy.txt

2.how cam rename the files:

  for instance: xxxxx_ggg_yyyyy_1.txt======>changed to ggg1a.txt


3.after the files read in, how can i only keep the rows with the aaa and
bbb, everything elses show be removed from the files, but the files still
remain the same file name?

   for instance, in the xxxxx_ggg_yyyyy_1.txt file, it shouls looks like:
 name    count

1. aaa    100
2. bbb    2000
3. aaa    300
4. bbb    400


Thanks so lot, I am very new to R, I am looking forward to any helps from
you.
   
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?list.files
In particular look at pattern argument.

?file.rename
?lapply
?read.table
?"["


Nikhil Kaza
Asst. Professor,
City and Regional Planning
University of North Carolina

nikhil.list at gmail.com

On Jul 7, 2010, at 1:11 PM, jd6688 wrote:
>
> Here are what i am going to accomplish:
>
> I have 400 files named as xxx.txt. the content of the file looks  
> like the
> following:
>
>    name    count
>
> 1. aaa     100
> 2. bbb    2000
> 3. ccc    300
> 4. ddd   3000
>
> ........
> more that 1000 rows in each files.
>
> these are the areas i need help:
> 1. how can i only read in the files with the string patterns ggg or  
> fff as
> part of the file names?
>  for instance, I only need the file names with the ggg or fff in it
>     xxxxx_ggg_yyyyy_1.txt
>     yyyy_fff_yyyy_xxx.txt
>
>    i don't need to read in the files, such as xxxx_aaa_yyyy.txt
>
> 2.how cam rename the files:
>
>  for instance: xxxxx_ggg_yyyyy_1.txt======>changed to ggg1a.txt
>
>
> 3.after the files read in, how can i only keep the rows with the aaa  
> and
> bbb, everything elses show be removed from the files, but the files  
> still
> remain the same file name?
>
>   for instance, in the xxxxx_ggg_yyyyy_1.txt file, it shouls looks  
> like:
> name    count
>
> 1. aaa    100
> 2. bbb    2000
> 3. aaa    300
> 4. bbb    400
>
>
> Thanks so lot, I am very new to R, I am looking forward to any helps  
> from
> you.
>
> -- 
> View this message in context:
http://r.789695.n4.nabble.com/Batch-files-process-and-String-parsing-tp2281208p2281208.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
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http://www.R-project.org/posting-guide.html
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