[R] formatting a list

jim holtman jholtman at gmail.com
Sun Oct 21 23:47:36 CEST 2007


That is what I thought and that is the format that the 'scan' approach
should provide.  I was just confused when you said that you were going
to have to transpose it, write it and then read it back in for some
reason.  I understand that Excel can not handle 7000 columns, but was
wondering where that came into play.

On 10/21/07, Tomas Vaisar <tvaisar at u.washington.edu> wrote:
> The data I have is tab delimited file with 7000 lines of 19 values each
> (representing 7000 permutations on 19 variables). I want to get it into
> the ROCR package which expects the data to be in lists - single list of
> 19 values for each permutation, e.g. list of 7000 lists of 19 values each.
>
> I hope this is little clearer.
>
> Tomas
>
> jim holtman wrote:
> > What is it that you want to do?  The 'scan' statement give you a list
> > of length 7000 with 19 entries each.  Do you want to create a matrix
> > that has 7000 rows by 19 columns?  If so, then you just have to take
> > the output of the 'scan' and do:
> >
> > x.matrix <- do.call('rbind', x)  # gives 7000 x 19 matrix.
> >
> > So I am still not sure exactly what your input is and what you want to
> > do with it.
> >
> > On 10/21/07, Tomas Vaisar <tvaisar at u.washington.edu> wrote:
> >
> >> Hi Jim,
> >>
> >> thanks a lot.  It works, however - my other problem is that I need to
> >> transpose the original table before reading it into the list because the
> >> data come from Excel and it can't handle 7000 columns.  I could read it
> >> in R transpose end write into a new tab delim file and then read it back
> >> in,  but I would think that there might be a way in R to do both.
> >> Would you know about the way?
> >>
> >> Tomas
> >>
> >> jim holtman wrote:
> >>
> >>> another choice is:
> >>>
> >>> x <- scan('temp.txt', what=c(rep(list(0), 19)))
> >>>
> >>> On 10/20/07, Tomas Vaisar <tvaisar at u.washington.edu> wrote:
> >>>
> >>>
> >>>> Hi,
> >>>>
> >>>> I am new to R and need to read in a file with 19 columns and 7000 rows
> >>>> and make it into a list of 7000 lists with 19 items each.  For a
> >>>> simpler case of 10 by 10 table I used x <-scan("file",
> >>>> list(0,0,0,0,0,0,0,0,0,0)), perhaps clumsy, but it did the job.
> >>>> However with the large 19x7000 (which needs to be transposed) I am not
> >>>> sure how to go about it.
> >>>>
> >>>> Coudl somebody suggest a way?
> >>>>
> >>>> Thanks,
> >>>>
> >>>> Tomas
> >>>>
> >>>> ______________________________________________
> >>>> 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
Cincinnati, OH
+1 513 646 9390

What is the problem you are trying to solve?



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