Here is a start on what you want to do. This generates some test data and then does a couple of summaries:
> # generate some data > N <- 1000 > x <- data.frame(date=as.character(20070000 + sample(1:4, N, TRUE) * 100 + sample(1:31, N, TRUE)), + value=runif(N)) > head(x) # display the data date value 1 20070124 0.07904540 2 20070117 0.17864565 3 20070109 0.86078870 4 20070205 0.93952259 5 20070112 0.87904425 6 20070323 0.01717623 > # assuming you read it in as character, convert to Date for processing > x$date <- as.Date(strptime(x$date, "%Y%m%d")) > x <- x[order(x$date), ] # order by date for plotting > plot(x$date, x$value, type='l') # plot the data > # show counts by month > table(months(x$date)) April February January March 238 236 253 237 > # average by month > aggregate(x$value, list(months(x$date)), mean) Group.1 x 1 April 0.4791387 2 February 0.5010831 3 January 0.5114135 4 March 0.4695668 > On 2/15/07, Sérgio Nunes <[EMAIL PROTECTED]> wrote: > > Hi, > > I have several files with data in this format: > > 20070102 > 20070102 > 20070106 > 20070201 > ... > > The data is sorted and each line represents a date (YYYYMMDD). I would > like to analyze this data using R. For instance, I would like to have > a histogram by year, month or day. > > I've already made a simple Perl script that aggregates this data but I > believe that R can be much more powerful and easy on this kind of > work. > > Any suggestions on where to start? > > Thanks in advance, > Sérgio Nunes > > ______________________________________________ > R-help@stat.math.ethz.ch 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? [[alternative HTML version deleted]]
______________________________________________ R-help@stat.math.ethz.ch 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.