[R] The most common row in a matrix?

Hi, How do you get the most common row from a matrix? If I have a matrix like this array(1:3,dim=c(4,5)) [,1] [,2] [,3] [,4] [,5] [1,]12312 [2,]23123 [3,]31231 [4,]12312 in which rows 1 and 4 are similar, I

Re: [R] The most common row in a matrix?

try this: mat - array(1:3, dim = c(4, 5)) # ind - table(apply(mat, 1, paste, collapse = /)) ind - which.max(ind) as.numeric(strsplit(names(ind), /)[[1]]) I hope it helps. Best, Dimitris Dimitris Rizopoulos Ph.D. Student Biostatistical Centre School of Public Health Catholic

Re: [R] The most common row in a matrix?

Try this: a - matrix(1:3, 4, 5) a.ag - aggregate(1:nrow(a), as.data.frame(a), length) a.ag[which.max(a.ag$x), 1:ncol(a)] On 11/19/06, kone [EMAIL PROTECTED] wrote: Hi, How do you get the most common row from a matrix? If I have a matrix like this array(1:3,dim=c(4,5)) [,1] [,2]

Re: [R] The most common row in a matrix?

Hi Gabor, Your version works with the small sample matrix but I didn't get it to work with a larger 675x8 -matrix. I don't know why. I don't know the command aggregate if there is something. I got this one from Peter Alspach which.max(table(paste(data.frame(t(MATRIX)), sep=','))) and it seems