find maximum values for each row in list in r?

Question

I have a lists of list in r. I want to find maximum values for each row in each list.

Here is my data:

$`01-2020`
$`01-2020`$h1
 [1] 5 5 5 1 6 1 6 4 4 2

$`01-2020`$h2
[1] 5 1 7 0 8


$`02-2020`
$`02-2020`$h1
[1] 0 0 0 0 1 2 1 1 1

$`02-2020`$h2
[1] 10  8  7  5  4

and its structure:

data<-list(`01-2020` = list(h1 = c(5, 5, 5, 1, 6, 1, 6, 4, 4, 2), h2 = c(5, 
    1, 7, 0, 8)), `02-2020` = list(h1 = c(0, 0, 0, 0, 1, 2, 1, 1, 
    1), h2 = c(10, 8, 7, 5, 4)))

I want to obtain these output values:

$`01-2020`
$`01-2020`$h1
[1] 6

$`01-2020`$h2
[1] 8


$`02-2020`
$`02-2020`$h1
[1] 2

$`02-2020`$h2
[1] 10

And also I see outputs like this:

But what I want to see is like the example below. I mean, without blue down arrow. also like double[2x1], not separate double[1] rows :

Answer 1

We can use rrapply

library(rrapply)
rrapply(data, f = max)

-output

#$`01-2020`
#$`01-2020`$h1
#[1] 6

#$`01-2020`$h2
#[1] 8


#$`02-2020`
#$`02-2020`$h1
#[1] 2

#$`02-2020`$h2
#[1] 10

Or as @27 ϕ 9 suggested in the comments, a base R alternative is rapply

rapply(data, max, how = "list")

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Or another option is a nested lapply from base R

lapply(data, function(x) lapply(x, max))

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Or to get the structure correctly

 out <- lapply(data, function(x) unname(sapply(x, max)))