[R] grep lines before or after pattern matched?

Joshua Wiley jwiley.psych at gmail.com
Mon Jul 11 18:45:45 CEST 2011

Dear Simon,

Maybe I don't understand properly....if you are doing this in R, can't
you just pick the line you want?


## print your data to clipboard
cat("Document 1 of 100 \n \n \n Newspaper Name \n \n Day Date", file =
## read data in, and only select the 4th line to pass to grep()
grep("pattern", x = readLines("clipboard")[4])

On Mon, Jul 11, 2011 at 9:31 AM, Simon Kiss <sjkiss at gmail.com> wrote:
> Dear colleagues,
> I have a series of newspaper articles in a text file, downloaded from a text file.  They look as follows:
> Document 1 of 100
> \n
> \n
> \n
> Newspaper Name
> \n
> \n
> Day Date
> I have a series of grep scripts that can extract the date and convert it to a date object, but I can't figure out how to grep the newspaper name.  There is no field ID attached to those lines. The best I can come up with would be to have the program grep the four lines following matching the pattern "Document [0-9]".  There is an an argument to grep in unix that can do this ...grep -A4 'pattern' infile>outfile, but I don't know if there is an equivalent argument in R.
> Any thoughts.
> Yours, Simon Kiss
> *********************************
> Simon J. Kiss, PhD
> Assistant Professor, Wilfrid Laurier University
> 73 George Street
> Brantford, Ontario, Canada
> N3T 2C9
> Cell: +1 905 746 7606
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Joshua Wiley
Ph.D. Student, Health Psychology
University of California, Los Angeles

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