dplyr to output class data.frame

Question

I can summarise a data frame with dplyr like this:

mtcars %>%
group_by(cyl) %>%
summarise(mean(mpg))

To convert the output back to class data.frame, my current approach is this:

as.data.frame(mtcars %>%
group_by(cyl) %>%
summarise(mean(mpg)))

Is there any way to get dplyr to output a class data.frame without having to use as.data.frame?

Answer 1

As was pointed out in the comments you might not need to convert it since it might be good enough that it inherits from data frame. If that is not good enough then this still uses as.data.frame but is slightly more elegant:

mtcars %>%
   group_by(cyl) %>%
   summarise(mean(mpg)) %>%
   ungroup %>%
   as.data.frame()

ADDED I just read in the comments that the reason you want this is to avoid the truncation of printed output. In that case just define this option, possibly in your .Rprofile file:

options(dplyr.print_max = Inf)

(Note that you can still hit the maximum defined by the "max.print" option associated with print so you would need to set that one too if it's also too low for you.)

Update: Changed %.% to %>% to reflect changes in dplyr.

Answer 2

In addition to what G. Grothendieck mentioned above, you can convert it into a new dataframe:

new_summary <- mtcars %>%
   group_by(cyl) %>%
   summarise(mean(mpg)) %>%
   as.data.frame()