Hi all, I want sort the data by ID and Y2 then count the number of rows within IDs. Assign a "flag" variable to reach row starting from first to the last row. For instance, in the following data ID "1" has three rows and each row is assigned flag sequentially 1, 2,3.
2. In the second step, within each ID, I want get the difference between the subsequent row values of y1 and y2(date) values. Within each ID the first value of y1diff and y2diff are always 0. The second values for each will be the current row minus the previous row. lag<-read.table(text=" ID, y1, y2 ID,Y1,y2 1,0,12/25/2014 1,125,9/15/2015 1,350,1/30/2016 2,0,12/25/2012 2,450,9/15/2014 2,750,1/30/2016 2, 656, 11/30/2016 ",sep=",",header=TRUE) output looks like as follows ID,flag,y1,y2,y1dif,y2dif 1,1,0,12/25/2014,0,0 1,2,125,9/15/2015,125,264 1,3,350,1/30/2016,225,137 2,1,0,12/25/2012,0,0 2,2,450,9/15/2014,450,629 2,3,750,1/30/2016,300,502 2, 4, 656 11/30/2016, -94, 305 Thank you ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
