Split a data frame column containing a list into multiple columns using dplyr (or otherwise)

Question

Consider the following example data

library(dplyr)
tmp <- mtcars %>%
    group_by(cyl) %>%
    summarise(mpg_sum = list(summary(mpg)))

Answer 1

As commented, you can also use the tidy function from package broom:

library(broom)
mtcars %>% group_by(cyl) %>% do(tidy(summary(.$mpg)))
# Source: local data frame [3 x 7]
# Groups: cyl [3]
# 
#     cyl minimum    q1 median  mean    q3 maximum
#   (dbl)   (dbl) (dbl)  (dbl) (dbl) (dbl)   (dbl)
# 1     4    21.4 22.80   26.0 26.66 30.40    33.9
# 2     6    17.8 18.65   19.7 19.74 21.00    21.4
# 3     8    10.4 14.40   15.2 15.10 16.25    19.2