How to join matrices of different row length from a list

Hi,

I have several matrix in a list, for example:
e
[[1]]
? ? [,1] [,2]
[1,] ? ?1 ? ?3
[2,] ? ?2 ? ?4

[[2]]
? ? [,1] [,2]
[1,] ? ?1 ? ?4
[2,] ? ?2 ? ?5
[3,] ? ?3 ? ?6

[[3]]
? ? [,1] [,2]
[1,] ? ?2 ? ?1

I would like to join them by column i.e.
? ? [,1] [,2] ? [,3] [,4][,5] [,6]
[1,] ? ?1 ? ?3 ? 1 ? ?4 ? ?2 ? ?1
[2,] ? ?2 ? ?4 ? 2 ? ?5 ? NA ?NA
[3,] ? NA ?NA ?3 ? ?6 ? NA ? NA

I have tried ?do.call(cbind,e) but I get this error message as the rows are
of different length-
Error in function (..., deparse.level = 1) ?:
?number of rows of matrices must match (see arg 2)

One reasonably simple approach is to convert your matrices to time
series (either ts series or zoo series) as cbind.ts and cbind.zoo both
NA fill.

L <- list(matrix(1:4, 2, 2), matrix(1:6, 3, 2), matrix(2:1, 1, 2))


# using ts
M <- unclass(do.call(cbind, lapply(L, ts)))
tsp(M) <- colnames(M) <- NULL

# With zoo its slightly shorter:

library(zoo)
M <- coredata(do.call(cbind, lapply(L, zoo)))
colnames(M) <- NULL


We can omit the colnames(M) <- NULL part in both cases if the list
itself or the constituent matrices have column names, e.g.

L <- list(A = matrix(1:4, 2, 2), B = matrix(1:6, 3, 2), C = matrix(2:1, 1, 2))

# or

L <- list(cbind(a = 1:2, b = 3:4), cbind(c = 1:3, d = 4:6), cbind(e = 2, f = 1))

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