a summary table of n (%)

Question

I am trying to create a summary table with only N and %s formatted like this.

data("mtcars")

am (N [%])
   0         19  [59%]
   1          13 [41%]
gear (N [%])
  3           15 [46%]
  4           12 [37.5%] 
  5            5 [15.6%]
carb (N [%])
  1            7  [21.8%]
  2            10 [31.2%] 
  3            3  [09.3%]
  4            10 [31.2%] 
  6            1  [03.1%] 
  8            1  [03.1%] 

Right now I am only thinking about table and prop.table but I am not sure how to generate the summary table like this efficiently. Any suggestion much appreciated. Thanks in advance.

Answer 1

Probably you can try the following approach as an example

mtcars %>%
  select(am, gear, carb) %>%
  lapply(\(x) {
    as.data.frame(
      table(x)
    ) %>%
      mutate(perc = proportions(Freq) * 100)
  })

which gives

$am
  x Freq   perc
1 0   19 59.375
2 1   13 40.625

$gear
  x Freq   perc
1 3   15 46.875
2 4   12 37.500
3 5    5 15.625

$carb
  x Freq   perc
1 1    7 21.875
2 2   10 31.250
3 3    3  9.375
4 4   10 31.250
5 6    1  3.125
6 8    1  3.125