A iterative and lagging function similar to diff in R, but not just difference?
r
Solution
You can use `zoo::rollapply`
require(zoo)
x <- c(1, 2, 1, 3, 11, 7, 5)
rollapply(x, width = 2, FUN = sum)
## [1] 3 3 4 14 18 12
Problem
The diff function in R returns suitably lagged and iterated differences. ``` x = c(1, 2, 1, 3, 11, 7, 5) diff(x) # [1] 1 -1 2 8 -4 -2 diff(x, lag=2) [1] 0 1 10 4 -6 ``` Is there anyway to customize this so that we can use functions other than difference? For example, sum: ``` itersum(x) # 3 3 4 14 18 12 ```