rowwise {dplyr} | R Documentation |
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()
.
df <- expand.grid(x = 1:3, y = 3:1) df_done <- df %>% rowwise() %>% do(i = seq(.$x, .$y)) df_done df_done %>% summarise(n = length(i))