Hi, This feels like a kinda dumb basic question, but I haven't been able to figure it out. I have a bunch of csv files I'd like to put into one csv using R. I have tried cat, append, join, aggregate, and a bunch of other things, but none of them really work for combining the data. If it's one of those listed, then my syntax is goofy. The csv files have different row numbers but the same columns. I just want to add each one to the end of the other. I've removed the heading from all but one of them (but I could easily get the headings all back if that helps). Thanks for the help! Tyler [[alternative HTML version deleted]]
I guess you could simply read the files into a loop and write into the aggregated files using write.table with append = true in the same loop -----Original Message----- From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf Of aeneas24 at priest.com Sent: 15 October 2010 08:47 To: r-help at r-project.org Subject: [R] Joining together multiple csv files Hi, This feels like a kinda dumb basic question, but I haven't been able to figure it out. I have a bunch of csv files I'd like to put into one csv using R. I have tried cat, append, join, aggregate, and a bunch of other things, but none of them really work for combining the data. If it's one of those listed, then my syntax is goofy. The csv files have different row numbers but the same columns. I just want to add each one to the end of the other. I've removed the heading from all but one of them (but I could easily get the headings all back if that helps). Thanks for the help! Tyler [[alternative HTML version deleted]] ______________________________________________ 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.
Hi:
Here's a toy example: the first part is to create files and write them out
to the current directory.
# Create a dummy file and run it five times, creating five new .csv files
file <- data.frame(x = rnorm(5), y = rnorm(5))
fnames <- paste('file', 1:5, '.csv', sep = '')
# last column is an indicator of the file number
for(i in seq_along(fnames)) write.csv(cbind(file, gp = rep(i, 5)), file
fnames[i])
# Now read them back into R and row concatenate them:
# Method 1:
# read the data files into a list
l <- lapply(fnames, read.csv)
# row concatenate them together
do.call(rbind, l)
# Method 2:
# Use package plyr to slurp the files together:
library(plyr)
ldply(fnames, read.csv)
HTH,
Dennis
On Thu, Oct 14, 2010 at 8:16 PM, <aeneas24@priest.com> wrote:
>
> Hi,
>
> This feels like a kinda dumb basic question, but I haven't been able to
> figure it out.
>
> I have a bunch of csv files I'd like to put into one csv using R.
>
> I have tried cat, append, join, aggregate, and a bunch of other things, but
> none of them really work for combining the data. If it's one of those
> listed, then my syntax is goofy. The csv files have different row numbers
> but the same columns. I just want to add each one to the end of the other.
>
> I've removed the heading from all but one of them (but I could easily
get
> the headings all back if that helps).
>
> Thanks for the help!
>
> Tyler
>
>
>
>
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help@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.
>
[[alternative HTML version deleted]]