[R] How to exclude lines that match certain regex when using read.table?

[Sharpie]

pengyu.ut wrote:
> 
> I'm thinking of using external program 'grep' and pipe() to do so. But
> I'm wondering if there is a more efficient way to do so purely in R
> 

I would just suck the whole table in using read.table(), locate the lines
that I don't want using apply() and grepl() and then reduce the data set:

  dataSet <- read.table( "someData.txt" )

  dataToDrop <- apply( dataSet, 1, function( row ){

    return(
      any( grepl( "regex", row ) )
    )

  })

  dataSet <- subset( dataSet, !dataToDrop )

Since this solution executes entirely in R without resorting to system()
calls, it should be portable between platforms.

-Charlie
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