Dear all, I could not find an answer for the problem.
I have a matrix and I want to sum rows in groups i.e. rows are summed as long as rows of column 1 have some value (f.e. 2008 in it), then again rows are summed as long as rows of column 2 have some value (f.e. 2009 in it). In case there is a repetition of value in column 1 in another group, this group should be summed seperately. Example: I have such a matrix: *1.2008* 3 2 2 *2.2008* 4 3 3 * 3.2008* 5 4 4 * 4.2008* 3 3 1 *1.2009* 6 1 2 *2.2009* 3 2 5 *1.2010* 4 4 3 * 2.2010* 3 3 2 *3.2010* 1 5 3 *4.2010* 2 2 2 * 1.2008* 3 1 1 *2.2008* 4 3 2 *3.2008* 2 4 3 *1.2009* 1 2 4 *2.2009* 5 4 3 *3.2009* 4 3 3 *1.2010* 4 3 1 *2.2010* 2 2 2 The result should be like this: *2008* 15 12 10 *2009* 9 3 7 *2010* 10 14 10 *2008* 9 8 6 *2009* 10 9 10 *2010* 6 5 3 Could You help me with that? Yours, Andrew Gaska -- View this message in context: http://r.789695.n4.nabble.com/Summing-rows-by-years-each-time-separately-tp4276428p4276428.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.
