expand: Expand a data.table to use all combinations of values

View source: R/expand.R

expandR Documentation

Expand a data.table to use all combinations of values

Description

Generates all combinations of variables found in a dataset.

expand() is useful in conjunction with joins:

  • use with right_join() to convert implicit missing values to explicit missing values

  • use with anti_join() to find out which combinations are missing

nesting() is a helper that only finds combinations already present in the dataset.

Usage

expand(.df, ..., .name_repair = "check_unique", .by = NULL)

nesting(..., .name_repair = "check_unique")

Arguments

.df

A data.frame or data.table

...

Columns to get combinations of

.name_repair

Treatment of duplicate names. See ?vctrs::vec_as_names for options/details

.by

Columns to group by

Examples

df <- tidytable(x = c(1, 1, 2), y = c(1, 1, 2))

df %>%
  expand(x, y)

df %>%
  expand(nesting(x, y))

mtfairbanks/gdt documentation built on Jan. 6, 2023, 6:47 a.m.