Hi, May be this helps: dat1<- read.table(text=" P1_prom Nom 1 -6.17 Pt_00187 2 -6.17 Pt_00187 3 -6.17 Pt_00187 4 -6.17 Pt_00187 5 -6.17 Pt_00187 6 -6.17 Pt_01418 7 -5.77 Pt_01418 8 -5.37 Pt_01418 9 -4.97 Pt_01418 10 -4.57 Pt_01418 ",sep="",header=TRUE,stringsAsFactors=FALSE)
library(zoo) dat1$PT_promMean<-rollmean(dat1$P1_prom,5,fill=NA,align="left") dat1 # P1_prom Nom PT_promMean #1 -6.17 Pt_00187 -6.17 #2 -6.17 Pt_00187 -6.17 #3 -6.17 Pt_00187 -6.09 #4 -6.17 Pt_00187 -5.93 #5 -6.17 Pt_00187 -5.69 #6 -6.17 Pt_01418 -5.37 #7 -5.77 Pt_01418 NA #8 -5.37 Pt_01418 NA #9 -4.97 Pt_01418 NA #10 -4.57 Pt_01418 NA A.K. Hello all, I have a big data frame that looks like this: P1_prom Nom 1 -6.17 Pt_00187 2 -6.17 Pt_00187 3 -6.17 Pt_00187 4 -6.17 Pt_00187 5 -6.17 Pt_00187 6 -6.17 Pt_01418 7 -5.77 Pt_01418 8 -5.37 Pt_01418 9 -4.97 Pt_01418 10 -4.57 Pt_01418 - - - 25000 where Nom represents a point in a map, and P1_prom represents the value of an operation we perfomed on each point (note that we performed 5 repetitions for each point, hence, each point has 5 values). What I am trying to do, with no success, is to create a new column, in which each row corresponds to the mean value of P1_prom for each point. So basically what I need the program to do is to write in the first row of the new column the average of the first five values of P1_prom, in the second row the average of the next five values, and so on. Could anybody guide me on how to do this. Thank you very much, Veronica ______________________________________________ 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.
