Very interesting. Does not produce a solution outright, but may be still usable
> df <- data.frame(x1=c(rep(1,10),rep(2,7)),x2=rep(1:17)) > aggregate(df$x2,by=list(x1=df$x1),cumsum)-> a1 > a1 x1 x 1 1 1, 3, 6, 10, 15, 21, 28, 36, 45, 55 2 2 11, 23, 36, 50, 65, 81, 98 > dim(a1) [1] 2 2 > a1[1,2] $`0` [1] 1 3 6 10 15 21 28 36 45 55 > a1[2,2] $`1` [1] 11 23 36 50 65 81 98 > class(a1[2,2]) [1] "list" If anybody can suggest how to create a reshape-able dataframe out of this, please speak. Ideally I should be able to use reshape(a1,dir="long",varying=2:11,idvar="x1",v.names="x") to get it back in long form. Thank everybody. Stephen B -----Original Message----- From: MacQueen, Don [mailto:macque...@llnl.gov] Sent: Wednesday, September 11, 2013 10:42 AM To: Bond, Stephen; r-help@r-project.org Subject: Re: [R] windowing >From the help page for the aggregate function: Compute Summary Statistics of Data Subsets Description: Splits the data into subsets, computes summary statistics for each, and returns the result in a convenient form. You might have to use cumsum() after the aggregation, if "unbounded preceding" causes a cumulative sum to be calculated. -Don -- Don MacQueen Lawrence Livermore National Laboratory 7000 East Ave., L-627 Livermore, CA 94550 925-423-1062 On 9/9/13 11:58 AM, "Bond, Stephen" <stephen.b...@cibc.com> wrote: >Is there a package or a command that does window aggregation like > >select >sum(col1) over >(partition by col2, col3 order by col4 >rows between unbounded preceding and current row) as sum1 >from table1 ; > >the above is Netezza syntax, but Postgre has same capability. > >Stephen B > > [[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. ______________________________________________ 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.
