imap {purrr} | R Documentation |
imap_xxx(x, ...)
, an indexed map, is short hand for
map2(x, names(x), ...)
if x
has names, or map2(x, seq_along(x), ...)
if it does not. This is useful if you need to compute on both the value
and the position of an element.
imap(.x, .f, ...) imap_lgl(.x, .f, ...) imap_chr(.x, .f, ...) imap_int(.x, .f, ...) imap_dbl(.x, .f, ...) imap_dfr(.x, .f, ..., .id = NULL) imap_dfc(.x, .f, ..., .id = NULL) iwalk(.x, .f, ...)
.x |
A list or atomic vector. |
.f |
A function, formula, or atomic vector. If a function, it is used as is. If a formula, e.g.
This syntax allows you to create very compact anonymous functions. If character vector, numeric vector, or list, it
is converted to an extractor function. Character vectors index by name
and numeric vectors index by position; use a list to index by position
and name at different levels. Within a list, wrap strings in |
... |
Additional arguments passed on to |
.id |
If not |
A vector the same length as .x
.
Other map variants: invoke
,
lmap
, map2
,
map
, modify
# Note that when using the formula shortcut, the first argument # is the value, and the second is the position imap_chr(sample(10), ~ paste0(.y, ": ", .x)) iwalk(mtcars, ~ cat(.y, ": ", median(.x), "\n", sep = ""))