skimr: how to get the top 3 and bottom 3 values?

Question

Consider this simple example

> tibble(value = c(1,2,3,4,5,5,6,7,8,9,10,11,12)) %>%
+   skim()
Skim summary statistics
 n obs: 13 
 n variables: 1 

-- Variable type:numeric -------------------------------------------------------
 variable missing complete  n mean   sd p0 p25 p50 p75 p100     hist
    value       0       13 13 6.38 3.48  1   4   6   9   12 ▅▂▇▂▂▅▂▅

I would simply add two columns top and bottom to the skimr output that show the top 3 and bottom 3 values, separated by a comma.

Something like

top        bottom
12,11,10   1,2,3

How can I do that? Thanks!

I didn't try it, but according the documentation, you can define your set of statistics. So I suppose that you can also define to get the top/bottom 3 values. — tmfmnk, Sep 11 '19 at 13:36

M.Viking · Answer 1 · 2019-09-11T14:56:22.637

Updated answer:

#remove the p values and histogram for space to work with
skim_with(numeric = list(p0 = NULL, p25 = NULL, p50=NULL, p75 = NULL, p100=NULL, hist=NULL))

#6 functions, for head 1 2 and 3, and tail 3 2 and 1.
h1<-function(x){head(sort(x))[1]}
h2<-function(x){head(sort(x))[2]}
h3<-function(x){head(sort(x))[3]}
t3<-function(x){tail(sort(x),3)[1]}
t2<-function(x){tail(sort(x),2)[1]}
t1<-function(x){tail(sort(x),1)[1]}

#assign those functions to return for numeric (need to do the same for integer and others)
skim_with(numeric = list(h1=h1, h2=h2, h3=h3, t3=t3, t2=t2, t1=t1))
skim(iris$Sepal.Length)

Skim summary statistics

── Variable type:numeric ────────────────────────────────────────────────
          variable missing complete   n mean   sd  h1  h2  h3  t3  t2  t1
 iris$Sepal.Length       0      150 150 5.84 0.83 4.3 4.4 4.4 7.7 7.7 7.9

score 2 · Accepted Answer · answered Sep 11 '19 at 15:16

OK I was able to make it work. For future reference:

get_top <- function(df) {
  df %>% as_tibble() %>% 
    top_n(3) %>% 
    pull() %>% 
    paste(collapse = ',')
}

skim_with(numeric = list(top = get_top), append = TRUE)

gives

> tibble(value = c(1,2,3,4,5,5,6,7,8,9,10,11,12)) %>%
+   skim()
Selecting by value
Skim summary statistics
 n obs: 13 
 n variables: 1 

-- Variable type:numeric -------------------------------------------------------
 variable missing complete  n mean   sd p0 p25 p50 p75 p100     hist      top
    value       0       13 13 6.38 3.48  1   4   6   9   12 ▅▂▇▂▂▅▂▅ 10,11,12

skimr: how to get the top 3 and bottom 3 values?

2 Answers2