On Wed, Oct 1, 2008 at 8:58 AM, Max Rausch <[EMAIL PROTECTED]> wrote: > I have a data frame with the following information > > day hour volume > 1 2003-07-18 10 836700 > 2 2003-07-18 11 375000 > 3 2003-07-18 12 60000 > 4 2003-07-18 8 1020000 > 5 2003-07-18 9 390000 > > I have been trying create a new data frame with the following > > day total_daily_volume > > I can accomplish this by bringing the data to excel and using a pivot table > but I would like to be able to do in R. I have been searching for several > hours but I can not figure out how to sum the the volume of each day.
You might want to have a look at the plyr (http://had.co.nz/plyr) and reshape (http://had.co.nz/reshape) packages which provide similar functionality to pivot tables in excel. Hadley -- http://had.co.nz/ ______________________________________________ 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.
