r - Extract elements from a list given the positions in another list -

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i have list of matrices follow.

listmat <- list(a=matrix(1:9, ncol=3), b=matrix(10:18, ncol=3)) listmat   $a      [,1] [,2] [,3] [1,]    1    4    7 [2,]    2    5    8 [3,]    3    6    9  $b      [,1] [,2] [,3] [1,]   10   13   16 [2,]   11   14   17 [3,]   12   15   18

i want extract 1st , 2nd column of matrix , 3rd column of b. these positions given in list.

listposition <- list(a=c(1,2), b=c(1)) listposition  $a [1] 1 2  $b [1] 1

is there way extract elements rather using following command

  listmat[["a"]][,1:2]    listmat[["b"]][,1]

we can use map extract corresponding matrix elements in list using index in listposition

map(function(x, y) x[, y, drop = false], listmat, listposition)

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