do function

Do anything

do() is superseded as of dplyr 1.0.0, because its syntax never really felt like it belonged with the rest of dplyr. It's replaced by a combination of reframe() (which can produce multiple rows and multiple columns), nest_by() (which creates a rowwise tibble of nested data), and pick() (which allows you to access the data for the "current" group).

do(.data, ...)

Arguments

• .data: a tbl
• ...: Expressions to apply to each group. If named, results will be stored in a new column. If unnamed, must return a data frame. You can use . to refer to the current group. You can not mix named and unnamed arguments.

Examples

# do() with unnamed arguments becomes reframe() or summarise()
# . becomes pick()
by_cyl <- mtcars %>% group_by(cyl)
by_cyl %>% do(head(., 2))
# ->
by_cyl %>% reframe(head(pick(everything()), 2))
by_cyl %>% slice_head(n = 2)

# Can refer to variables directly
by_cyl %>% do(mean = mean(.$vs))
# ->
by_cyl %>% summarise(mean = mean(vs))

# do() with named arguments becomes nest_by() + mutate() & list()
models <- by_cyl %>% do(mod = lm(mpg ~ disp, data = .))
# ->
models <- mtcars %>%
  nest_by(cyl) %>%
  mutate(mod = list(lm(mpg ~ disp, data = data)))
models %>% summarise(rsq = summary(mod)$r.squared)

# use broom to turn models into data
models %>% do(data.frame(
  var = names(coef(.$mod)),
  coef(summary(.$mod)))
)

# ->
models %>% reframe(broom::tidy(mod))