Instead of table(cut(x, br)), hist(x, br, plot = FALSE) is more efficient and less memory hungry.
Instead of cut(*, labels = FALSE), findInterval() is more efficient.
findInterval(x, vec): given a vector of non-decreasing breakpoints in vec, find the interval containing each element of x;
x <- 2:18
v <- c(5, 10, 15) # create two bins [5,10) and [10,15)
cbind(x,findInterval(x,v))
# x
# [1,] 2 0
# [2,] 3 0
# [3,] 4 0
# [4,] 5 1
# [5,] 6 1
# [6,] 7 1
# [7,] 8 1
# [8,] 9 1
# [9,] 10 2
#[10,] 11 2
#[11,] 12 2
#[12,] 13 2
#[13,] 14 2
#[14,] 15 3
#[15,] 16 3
#[16,] 17 3
#[17,] 18 3