Or... fs<-rep(1:ceiling(length(test)/10),each=10)[1:length(test)] result<-by(test,fs,mean)
which will get you the version with the 101st as a single datapoint so many possibilities.. On 23.01.2013, at 16:43, David L Carlson wrote: > You didn't indicate what you want to do with the 101st observation. Arun's > solution creates an 11th group and divides by the number in the group(1), > while Jessica's solution creates an 11th column and divides by 10. > >> test[101] <- 100 >> unlist(lapply(split(test,((seq_along(test)-1)%/% 10)+1),mean)) > 1 2 3 4 5 6 7 > > 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 > > 8 9 10 11 > 0.146375 0.000000 0.194500 100.000000 >> x<-matrix(test,nrow=10) > Warning message: > In matrix(test, nrow = 10) : > data length [101] is not a sub-multiple or multiple of the number of rows > [10] >> apply(x,2,mean) > [1] 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 > [8] 0.146375 0.000000 0.194500 10.000000 > > Another approach would be to use aggregate: > >> Groups <- gl(ceiling(length(test)/10), 10)[1:length(test)] >> aggregate(test, list(Groups), mean) > Group.1 x > 1 1 0.000000 > 2 2 0.000000 > 3 3 0.000000 > 4 4 0.000000 > 5 5 0.000000 > 6 6 0.000000 > 7 7 0.000000 > 8 8 0.146375 > 9 9 0.000000 > 10 10 0.194500 > 11 11 100.000000 > > ---------------------------------------------- > David L Carlson > Associate Professor of Anthropology > Texas A&M University > College Station, TX 77843-4352 > > >> -----Original Message----- >> From: r-help-boun...@r-project.org [mailto:r-help-bounces@r- >> project.org] On Behalf Of Jessica Streicher >> Sent: Wednesday, January 23, 2013 6:13 AM >> To: Wim Kreinen >> Cc: r-help >> Subject: Re: [R] summarise subsets of a vector >> >> Or maybe >> >> x<-matrix(test,nrow=10) >> apply(x,2,mean) >> >> >> On 23.01.2013, at 00:09, Wim Kreinen wrote: >> >>> Hello, >>> >>> I have vector called test. And now I wish to measure the mean of the >> first >>> 10 number, the second 10 numbers etc >>> How does it work? >>> Thanks Wim >>> >>>> dput (test) >>> c(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, >>> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, >>> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, >>> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.71, 0.21875, 0, 0.27375, 0.26125, >>> 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.84125, >>> 0.0575, 0.92625, 0.12, 0, 0) >>> >>> [[alternative HTML version deleted]] >>> >>> ______________________________________________ >>> 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. > ______________________________________________ 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.
