elementwise combination of two lists in R
elementwise-operations, r
Solution
`expand.grid(list.a, list.b)` gives you the desired result in a `data.frame`. This tends to be the most useful format for working with data in R. However, you could get the exact structure you ask for (save the ordering) with a call to `apply` and `lapply`:
result.df <- expand.grid(list.a, list.b)
result.list <- lapply(apply(result.df, 1, identity), unlist)
If you want this list ordered by the first element:
result.list <- result.list[order(sapply(result.list, head, 1))]
Problem
Say I have two lists: ``` list.a <- as.list(c("a", "b", "c")) list.b <- as.list(c("d", "e", "f")) ``` I would like to combine these lists recursively, such that the result would be a list of combined elements as a vector like the following: ``` [[1]] [1] a d [[2]] [1] a e [[3]] [1] a f [[4]] [1] b d ``` and so on. I feel like I'm missing something relatively simple here. Any help? Cheers.