Re: [R] cumulative sum in data frame

2009-06-17 Thread Jorge Ivan Velez
Dear Steve, Using Jim Holtman's x data, you can also try the following for columns 3 and 4: a <- with(x, apply(x[,3:4], 2, tapply, site,function(x) cumsum(x))) x[,c('cvar1','cvar2')] <- do.call(cbind,lapply(a, function(x) do.call(c,x))) x HTH, Jorge On Wed, Jun 17, 2009 at 11:48 AM, SEUNG CHEO

Re: [R] cumulative sum in data frame

2009-06-17 Thread jim holtman
Here is one way of doing it: > x <- read.table(textConnection("sitedistancevar1var2 + 1 10 1 0 + 1 20 0 1 + 1 30 1 2 + 1 40 3 3 + 1 50 1 4 + 2 10

[R] cumulative sum in data frame

2009-06-17 Thread SEUNG CHEON HONG
Dear R-Help List, I have a question about data manipulation. I tried to make code myself but too much for me. I would greatly appreciate your help. I have data set consisting of site (from 1 to N1) and distance and there are several variables (1 to N2) collected from each sampling site. I am in