collapse: rsplit – R documentation

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rsplit

Recursive Splitting

Description

rsplit recursively splits a vector or data frame into subsets according to combinations of (multiple) vectors / factors - by default returning a (nested) list. If flatten = TRUE, the list is flattened yielding the same result as split. rsplit is also faster than split, particularly for data frames.

Usage

rsplit(x, ...)

## Default S3 method:
rsplit(x, fl, drop = TRUE, flatten = FALSE, ...)

## S3 method for class 'data.frame'
rsplit(x, by, drop = TRUE, flatten = FALSE, cols = NULL,
       keep.by = FALSE, simplify = TRUE, ...)

Arguments

`x`	a vector, data.frame or list.
`fl`	a vector, factor or list of vectors / factors used to split `x`.
`by`	data.frame method: Same as `fl`, but also allows one- or two-sided formulas i.e. `~ group1` or `var1 + var2 ~ group1 + group2`. See Examples.
`drop`	logical. `TRUE` removes unused levels or combinations of levels from factors before splitting; `FALSE` retains those combinations yielding empty list elements in the output.
`flatten`	logical. If `fl` is a list of vectors / factors, `TRUE` calls `finteraction` on the list, creating a single factor used for splitting; `FALSE` yields recursive splitting.
`cols`	data.frame method: Select columns to split using a function, column names, indices or a logical vector. Note: `cols` is ignored if a two-sided formula is passed to `by`.
`keep.by`	logical. If a formula is passed to `by`, then `TRUE` preserves the splitting (right-hand-side) variables in the data frame.
`simplify`	data.frame method: Logical. `TRUE` calls `rsplit.default` if a single column is split e.g. `rsplit(data, col1 ~ group1)` becomes the same as `rsplit(data$col1, data$group1)`.
`...`	further arguments passed to `split`.

Value

a (nested) list containing the subsets of x.

Examples

rsplit(mtcars$mpg, mtcars$cyl)
rsplit(mtcars, mtcars$cyl)

rsplit(mtcars, mtcars[.c(cyl, vs, am)])
rsplit(mtcars, ~ cyl + vs + am, keep.by = TRUE)  # Same thing
rsplit(mtcars, ~ cyl + vs + am)

rsplit(mtcars, ~ cyl + vs + am, flatten = TRUE)

rsplit(mtcars, mpg ~ cyl)
rsplit(mtcars, mpg ~ cyl, simplify = FALSE)
rsplit(mtcars, mpg + hp ~ cyl + vs + am)
rsplit(mtcars, mpg + hp ~ cyl + vs + am, keep.by = TRUE)

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Advanced and Fast Data Transformation

v1.5.3

GPL (>= 2) | file LICENSE

Authors

Sebastian Krantz [aut, cre], Matt Dowle [ctb], Arun Srinivasan [ctb], Laurent Berge [ctb], Dirk Eddelbuettel [ctb], Josh Pasek [ctb], Kevin Tappe [ctb], R Core Team and contributors worldwide [ctb], Martyn Plummer [cph], 1999-2016 The R Core Team [cph]

Initial release

2021-03-05