[R] reading very large files

[juli g. pausas]

Hi all,
The small modification was replacing
Write.Rows <- Chunk[Chunk.Sel - Cuts[i], ]   # (2nd line from the end)
by
Write.Rows <- Chunk[Chunk.Sel - Cuts[i] ]    # Chunk has one dimension only

Running times:
- For the Jim Holtman solution (reading once, using diff and skiping
from one record to the other)
[1] 49.80  0.27 50.96    NA    NA

- For Marc Schwartz solution (reading in chunks of 100000)
[1] 1203.94    9.12 1279.04      NA      NA

Both in R2.4.1, under Windows:
> R.version
               _
platform       i386-pc-mingw32
arch           i386
os             mingw32
system         i386, mingw32
status
major          2
minor          4.1
year           2006
month          12
day            18
svn rev        40228
language       R
version.string R version 2.4.1 (2006-12-18)
>

Juli




On 03/02/07, Marc Schwartz <marc_schwartz at comcast.net> wrote:
> On Sat, 2007-02-03 at 19:06 +0100, juli g. pausas wrote:
> > Thank so much for your help and comments.
> > The approach proposed by Jim Holtman was the simplest and fastest. The
> > approach by Marc Schwartz also worked (after a very small
> > modification).
> >
> > It is clear that a good knowledge of R save a lot of time!! I've been
> > able to do in few minutes a process that was only 1/4th done after 25
> > h!
> >
> > Many thanks
> >
> > Juli
>
> Juli,
>
> Just out of curiosity, what change did you make?
>
> Also, what were the running times for the solutions?
>
> Regards,
>
> Marc
>
>
>


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