[R] Ignoring initial rows in a text file import

[jim holtman]

try this:

input  <- readLines("yourfile.txt")
# determine start
start <- grep("\tBegin Main\t", input)[1]  # first line if many
if (length(start) == 1 && (start > 1)){
    input <- tail(input, -(start - 1))  # delete heading lines
}
# find lines you want to delete
breaks <- grep("\tBreak\t", input)
if (length(breaks) > 0){
    input <- input[-breaks]
}
# now read in your data
real_input <- read.table(textConnection(input), header=TRUE)
closeAllConnections()



On Mon, May 31, 2010 at 7:51 PM, Kevin Burnham <kburnham at gmail.com> wrote:
> I am trying to import a series of text files generated by stimulus
> presentation software.  The problem that I am having is that the number of
> rows I need to skip is not fixed (depending on subject's pretest behavior)
> nor is the first row of the data I want always the same (the stimuli were
> presented in random order).  So I need to bring in the .txt file (using
> readLines?), look for the row containing the text "Begin Main" (see exact
> row below) and start reading data to a table from that point.
>
>  [13] "Main Group\t1000\tBegin Main\tBegin Main\tBegin Main\t\t
> \tPressed\t(any response)\tC\t25860\t\t\t\t\t"
>
> I would also like it to ignore the row:
> [173] "Main Group\t1000\tBreak\tBreak\
> tpause3\t\t \tPressed\t(any response)\tC\t47610\t\t\t\t\t"
>
> which will always be the same number of rows after the "Begin Main" row.
>
> Thanks,
> Kevin Burnham
>
>        [[alternative HTML version deleted]]
>
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-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem that you are trying to solve?