Hi, You can either write a small function that returns just the values you want, or use a convenience function within by, as in:
> by(RecallSmall[1:4,"value"],RecallSmall[1:4,"ID"], FUN=function(x){acf(x, > na.action=na.pass,plot=FALSE)$acf}) RecallSmall[1:4, "ID"]: 1 , , 1 [,1] [1,] 1.00 [2,] 0.15 [3,] -0.50 [4,] -0.15 But I suspect that you would get something more like what you want by splitting the data on ID, and then using sapply: > RecallSmall <- data.frame(ID=c(1,1,1,1,2,2,2,2), value=c(6,5,3,4,6,5,3,4)) > result <- split(RecallSmall[["value"]], RecallSmall[["ID"]]) > result <- sapply(result, FUN=function(x){acf(x, > na.action=na.pass,plot=FALSE)$acf}) > result 1 2 [1,] 1.00 1.00 [2,] 0.15 0.15 [3,] -0.50 -0.50 [4,] -0.15 -0.15 Sarah On Tue, May 10, 2022 at 1:29 PM Sorkin, John <jsor...@som.umaryland.edu> wrote: > > I am using the by function to run the acf function. Each run of the by > function returns more information than I want. All I want is the four values > that acf returns, which using the data below would be > 1.00 0.15 -0.50 -0.15 > How can I isolate these four values from the output returned by the by > function. > > Sample code: > > RecallSmall <- data.frame(ID=c(1,1,1,1),value=c(6,5,3,4)) > cat("Here are the data\n") > RecallSmall > cat("All I want is autocorrerlations, e.g. 1.00 0.15 -0.50 -0.15 \n ") > # attempting to subset does not work at all > by(RecallSmall[1:4,"value"],RecallSmall[1:4,"ID"],acf,na.action=na.pass,plot=FALSE)$acf > # this gives me more than I want, not just the numeric results. > by(RecallSmall[1:4,"value"],RecallSmall[1:4,"ID"],acf,na.action=na.pass,plot=FALSE) > > # For your reference, this is what the acf function returns > acf(RecallSmall[1:4,"value"],na.action=na.pass,plot=FALSE) > # For your reference, this is what the acf function returns when the output > is subset > acf(RecallSmall[1:4,"value"],na.action=na.pass,plot=FALSE)Thank you, John > > Thank you, > John > > > > > > > > > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. -- Sarah Goslee (she/her) http://www.numberwright.com ______________________________________________ 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.