### Example Data dat <-list() set.seed(1) dat[[1]] <- data.frame(matrix( rbinom(40, 1, .8),nrow=5)) dat[[2]] <- data.frame(matrix( rbinom(40, 1, .8),nrow=5)) ####Code x<-sapply(dat,"[",3) #Extracting the vector y<-lapply(x,rle) #Counting the sequences which is returned as a list z<-sapply(y,"[", 1) #extracting the first element of the list of sequence counts final<-sapply(z,"[",1) #extracting the first number, which gives the length of the first sequence, which I want final ###############
dat # or you can try this x <- sapply(dat, "[", 3) # extract the vector y <- lapply(x, rle) sapply(y, function(.row) c(length=.row$lengths[1], value=.row$values[1])) On Sat, Aug 2, 2008 at 5:07 AM, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > Hello everybody, > I have problem with a lapply command, which rather proves that I don't > fully understand it. > > I want to extract from a list that consists of dataframes, the length > of the first sequences from a given variable (its part of a simulation > exercises). > > Below is code which does the job, but I think it should be possible to > make it more compact. > > ### Example Data > dat <-list() > dat[[1]] <- data.frame(matrix( rbinom(40, 1, .8),nrow=5)) > dat[[2]] <- data.frame(matrix( rbinom(40, 1, .8),nrow=5)) > ####Code > x<-sapply(dat,"[",3) #Extracting the vector > y<-lapply(x,rle) #Counting the sequences which is returned as a list > z<-sapply(y,"[", 1) #extracting the first element of the list of > sequence counts > final<-sapply(z,"[",1) #extracting the first number, which gives the > length of the first sequence, which I want > final > ############### > > > > Thanks for your help, > Stefan > > ______________________________________________ > 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. > -- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve? ______________________________________________ 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.
