flatten
Flatten a list of lists into a simple vector.
These functions remove a level hierarchy from a list. They are similar to
unlist()
, only ever remove a single layer of hierarchy, and
are type-stable so you always know what the type of the output is.
Usage
flatten(.x)flatten_lgl(.x)
flatten_int(.x)
flatten_dbl(.x)
flatten_chr(.x)
flatten_dfr(.x, .id = NULL)
flatten_dfc(.x)
Arguments
- .x
A list of flatten. The contents of the list can be anything for
flatten
(as a list is returned), but the contents must match the type for the other functions.- .id
If not
NULL
a variable with this name will be created giving either the name or the index of the data frame.
Value
flatten()
returns a list, flatten_lgl()
a logical
vector, flatten_int()
an integer vector, flatten_dbl()
a
double vector, and flatten_chr()
a character vector.
flatten_dfr()
and flatten_dfc()
return data frames created by
row-binding and column-binding respectively. They require dplyr to
be installed.
Examples
# NOT RUN {
x <- rerun(2, sample(4))
x
x %>% flatten()
x %>% flatten_int()
# You can use flatten in conjunction with map
x %>% map(1L) %>% flatten_int()
# But it's more efficient to use the typed map instead.
x %>% map_int(1L)
# }