Sum every nth points

Question

I have a vector and I need to sum every n numbers and return the results. This is the way I plan on doing it currently. Any better way to do this?

Answer 1

v <- 1:100

n <- 10

cutpoints <- seq( 1 , length( v ) , by = n )

categories <- findInterval( 1:length( v ) , cutpoints )

tapply( v , categories , sum )