Install and load the "plyr" package and try something like: > ddply(d, .(date, color), summarize, + meanOpen=mean(measurement[door=="open"]), nOpen=sum(door=="open"), + meanClosed=mean(measurement[door=="closed"]), nClosed=sum(door=="closed")) date color meanOpen nOpen meanClosed nClosed 1 420 red 0.9741929 1 NaN 0 2 513 red 0.9352938 1 0.9620535 1 3 917 yellow NaN 0 0.9941022 1 4 1230 blue 0.9639099 1 0.9893108 1 5 1230 green 0.9765203 1 NaN 0
Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On > Behalf Of Jeffrey Joh > Sent: Monday, February 06, 2012 4:28 PM > To: r-help@r-project.org > Subject: [R] Table rearranging > > > I have a table that looks like this: > > measurement date door color > 0.93529385 513 open red > 0.97419293 420 open red > 0.962053514 513 closed red > 0.963909937 1230 open blue > 0.97652034 1230 open green > 0.989310795 1230 closed blue > 0.9941022 917 closed yellow > > I would like to create a table that has: Open measurement, Closed > measurement, date, color. For every > date/color combination, there should be two columns to represent the door > open/closed measurement. > > If there are multiple datapoints with a given door/date/color combination, > then they should be > averaged. > I would also like to make two columns to represent the number of > datapoints that were averaged in determining the open/closed > measurements. > > Jeffrey > > ______________________________________________ > 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.
