Apply function to a certain element and rewrite the elements in another vector of a nested list

Question

I have a nested vector

$a
$a$age
[1] -2702 -2621 -2945
$a$gen
[1] 109 109 105
$b
$b$age
[1] -2702 -2702 -2702
$b$gen
[1] 109 109 109

I want to divide the elements of $a$age to 25, round them up and the result write in $a$gen, as well as do the same with $b$age and result write in $b$gen

So the output should be

$a
$a$age
[1] -2702 -2621 -2945
$a$gen
[1] 108 104 117
$b
$b$age
[1] -2702 -2702 -2702
$b$gen
[1] 108 108 108

Answer 1

I do not know what you are trying to solve, although you could tackle the problem as :

x %>%
  map_df(data.frame, .id='grp')%>%
  mutate(gen = abs(ceiling(age/25)))%>%
  split(~grp)%>%
  map(~as.list(.x[-1]))


$a
$a$age
[1] -2702 -2621 -2945

$a$gen
[1] 108 104 117


$b
$b$age
[1] -2702 -2702 -2702

$b$gen
[1] 108 108 108