show str(...) as table in R Markdown

Question

Is there a library or function for r-markdown to show the structure of a dataframe as a table? Something similar tot the output of str(myDataFrame) but as a pretty formatted r-markdown table?

For example the following output should be shown as at least the colums holding the feature names, and the datatypes. Some example values would be nice but are not required.

str(mtcars)
'data.frame':   32 obs. of  11 variables:
 $ mpg : num  21 21 22.8 21.4 18.7 18.1 14.3 24.4 22.8 19.2 ...
 $ cyl : num  6 6 4 6 8 6 8 4 4 6 ...
 $ disp: num  160 160 108 258 360 ...
 $ hp  : num  110 110 93 110 175 105 245 62 95 123 ...
 $ drat: num  3.9 3.9 3.85 3.08 3.15 2.76 3.21 3.69 3.92 3.92 ...
 $ wt  : num  2.62 2.88 2.32 3.21 3.44 ...
 $ qsec: num  16.5 17 18.6 19.4 17 ...
 $ vs  : num  0 0 1 1 0 1 0 1 1 1 ...
 $ am  : num  1 1 1 0 0 0 0 0 0 0 ...
 $ gear: num  4 4 4 3 3 3 3 4 4 4 ...
 $ carb: num  4 4 1 1 2 1 4 2 2 4 ...

Answer 1

str uses cat so there is no way to transform it into a pretty data.frame to print. But you can mimic its functionalities to create one, and then pass it to your favorite rmarkdown table formatter (kable, pander, etc.):

library(knitr)
library(magrittr)
data.frame(variable = names(mtcars),
           classe = sapply(mtcars, typeof),
           first_values = sapply(mtcars, function(x) paste0(head(x),  collapse = ", ")),
           row.names = NULL) %>% 
  kable()

|variable |classe  |first_values                             |
|:--------|:-------|:----------------------------------------|
|mpg      |numeric |21, 21, 22.8, 21.4, 18.7, 18.1           |
|cyl      |numeric |6, 6, 4, 6, 8, 6                         |
|disp     |numeric |160, 160, 108, 258, 360, 225             |
|hp       |numeric |110, 110, 93, 110, 175, 105              |
|drat     |numeric |3.9, 3.9, 3.85, 3.08, 3.15, 2.76         |
|wt       |numeric |2.62, 2.875, 2.32, 3.215, 3.44, 3.46     |
|qsec     |numeric |16.46, 17.02, 18.61, 19.44, 17.02, 20.22 |
|vs       |numeric |0, 0, 1, 1, 0, 1                         |
|am       |numeric |1, 1, 1, 0, 0, 0                         |
|gear     |numeric |4, 4, 4, 3, 3, 3                         |
|carb     |numeric |4, 4, 1, 1, 2, 1                         |