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

I will add one more way of doing it without any function from apply family

v <- 1:100
n <- 10

diff(c(0, cumsum(v)[slice.index(v, 1)%%n == 0]))
##  [1]  55 155 255 355 455 555 655 755 855 955