Compute per-group cumulative sums

Compute per-group cumulative sums

cumsum_g(col, first_indices, na.rm = FALSE)

Arguments

col

vector to cumulative sum
first_indices

numeric index of first index in each group
na.rm

locial if TRUE remove NAs (empty sum is zero).

Value

per-group cumulative sum

Examples


v <- c(2, 3, 1, NA, 5)
fi <- c(1, 1, 3, 3, 3)
cumsum_g(v, fi)
#> [1]  2  5  1 NA NA