`rowwise()`

is used for the results of `do()`

when you
create list-variables. It is also useful to support arbitrary
complex operations that need to be applied to each row.

rowwise(data)

data | Input data frame. |
---|

Currently, rowwise grouping only works with data frames. Its
main impact is to allow you to work with list-variables in
`summarise()`

and `mutate()`

without having to
use `[[1]]`

. This makes `summarise()`

on a rowwise tbl
effectively equivalent to `plyr::ldply()`

.

#> Source: local data frame [9 x 1] #> Groups: <by row> #> #> # A tibble: 9 x 1 #> i #> * <list> #> 1 <int [3]> #> 2 <int [2]> #> 3 <int [1]> #> 4 <int [2]> #> 5 <int [1]> #> 6 <int [2]> #> 7 <int [1]> #> 8 <int [2]> #> 9 <int [3]>#> Error in UseMethod("summarise_"): no applicable method for 'summarise_' applied to an object of class "list"