How to cbind or rbind different lengths vectors without repeating the elements of the shorter vectors?

Question

cbind(1:2, 1:10)        [,1] [,2]     [1,]    1    1     [2,]    2    2     [3,]    1    3     [4,]    2    4     [5,]    1    5     [6,]    2    6     [7,]    1    7     [8,]    2    8     [9,]    1    9    [10,]    2   10   

I want an output like below

[,1] [,2]   [1,] 1 1   [2,] 2 2   [3,]   3   [4,]   4   [5,]   5   [6,]   6   [7,]   7   [8,]   8   [9,]   9   [10,]  10   

Answer 1

The trick is to make all your inputs the same length.

x <- 1:2 y <- 1:10 n <- max(length(x), length(y)) length(x) <- n                       length(y) <- n 

If you want you output to be an array, then cbind works, but you get additional NA values to pad out the rectangle.

cbind(x, y)        x  y  [1,]  1  1  [2,]  2  2  [3,] NA  3  [4,] NA  4  [5,] NA  5  [6,] NA  6  [7,] NA  7  [8,] NA  8  [9,] NA  9 [10,] NA 10 

To get rid of the NAs, the output must be a list.

Map(function(...)     {       ans <- c(...)       ans[!is.na(ans)]    }, as.list(x), as.list(y) ) [[1]] [1] 1 1  [[2]] [1] 2 2  [[3]] [1] 3  [[4]] [1] 4  [[5]] [1] 5  [[6]] [1] 6  [[7]] [1] 7  [[8]] [1] 8  [[9]] [1] 9  [[10]] [1] 10 

EDIT: I swapped mapply(..., SIMPLIFY = FALSE) for Map.