reorganize nested lists by element names: all elements with the same name together-CodePudding

I want to reorganize the grand list of dlist4 in such a way that all the a's stay in one nested list and all the b's in another nested list.

A = list(a = matrix(1:4, 2), b = matrix(2:5, 2))

G = list(a = matrix(10:13, 2), b = matrix(5:8, 2))

M_1 = list(a = matrix(10:13, 2), b = matrix(5:8, 2))

M_2 = list(a = matrix(2:5, 2), b = matrix(5:8, 2))

dlist4 <- tibble::lst(A, G, M_1, M_2)

The answers from these questions: R list - combine elements with same name and combine elements of list of lists with the same name got me close. I need the list structure to I removed the unlist(), but this result is unexpected.

tapply(dlist4,names(dlist4), FUN=function(x) unname(x))
$A
$A$a
     [,1] [,2]
[1,]    1    3
[2,]    2    4

$A$b
     [,1] [,2]
[1,]    2    4
[2,]    3    5


$G
$G$a
     [,1] [,2]
[1,]   10   12
[2,]   11   13

$G$b
     [,1] [,2]
[1,]    5    7
[2,]    6    8


$M_1
$M_1$a
     [,1] [,2]
[1,]   10   12
[2,]   11   13

$M_1$b
     [,1] [,2]
[1,]    5    7
[2,]    6    8


$M_2
$M_2$a
     [,1] [,2]
[1,]    2    4
[2,]    3    5

$M_2$b
     [,1] [,2]
[1,]    5    7
[2,]    6    8

I need a list of a that has four elements, a$A, a$G, a$M_1, and a$M_2, and the same with a list of b; and then a and b nested in a bigger list. Thanks so much for any hints.

CodePudding user response：

do.call(rlist::list.zip, dlist4)

purrr::lift(rlist::list.zip)(dlist4)

$a
$a$A
     [,1] [,2]
[1,]    1    3
[2,]    2    4

$a$G
     [,1] [,2]
[1,]   10   12
[2,]   11   13

$a$M_1
     [,1] [,2]
[1,]   10   12
[2,]   11   13

$a$M_2
     [,1] [,2]
[1,]    2    4
[2,]    3    5


$b
$b$A
     [,1] [,2]
[1,]    2    4
[2,]    3    5

$b$G
     [,1] [,2]
[1,]    5    7
[2,]    6    8

$b$M_1
     [,1] [,2]
[1,]    5    7
[2,]    6    8

$b$M_2
     [,1] [,2]
[1,]    5    7
[2,]    6    8