How to select elements with the same name from nested list with purrr?

Question

require(purrr)

list <- list( 
  node = list(a = list(y = 1, t = 1), b = list(y = 1, t = 2)),
  node = list(a = list(y = 1, t = 3), b = list(y = 1, t = 4))) 
<         


        

Answer 1

You can use modify_depth for this if you know what level you want to pull the information out of.

You want to pull t out for the nested lists, which is level 2.

modify_depth(list, 2, "t")

$node
$node$a
[1] 1

$node$b
[1] 2


$node
$node$a
[1] 3

$node$b
[1] 4

The purrr modify family of functions returns an object of the same type as the input, so you'd need to unlist to get a vector instead of a list.