expand_grid: Create a tibble from all combinations of inputs

In tidyverse/tidyr: Tidy Messy Data

Create a tibble from all combinations of inputs

Description

expand_grid() is heavily motivated by expand.grid(). Compared to expand.grid(), it:

• Produces sorted output by varying the first column the slowest by default.

• Returns a tibble, not a data frame.

• Never converts strings to factors.

• Does not add any additional attributes.

• Can expand any generalised vector, including data frames.

Usage

expand_grid(..., .name_repair = "check_unique", .vary = "slowest")

Arguments

...	Name-value pairs. The name will become the column name in the output.
.name_repair	One of "check_unique", "unique", "universal", "minimal", "unique_quiet", or "universal_quiet". See vec_as_names() for the meaning of these options.
.vary	One of: "slowest" to vary the first column slowest. This produces sorted output and is generally the most useful. "fastest" to vary the first column fastest. This matches the behavior of expand.grid().

Value

A tibble with one column for each input in .... The output will have one row for each combination of the inputs, i.e. the size will be equal to the product of the sizes of the inputs. This implies that if any input has length 0, the output will have zero rows. The ordering of the output depends on the .vary argument.

Examples

# Default behavior varies the first column "slowest"
expand_grid(x = 1:3, y = 1:2)

# Vary the first column "fastest", like `expand.grid()`
expand_grid(x = 1:3, y = 1:2, .vary = "fastest")

# Can also expand data frames
expand_grid(df = tibble(x = 1:2, y = c(2, 1)), z = 1:3)

# And matrices
expand_grid(x1 = matrix(1:4, nrow = 2), x2 = matrix(5:8, nrow = 2))

tidyverse/tidyr documentation built on Sept. 1, 2024, 6:19 p.m.