List all combinations of values

Source: R/cross_list.R

List all combinations of values

cross_list(...)

cross_tbl(...)

Arguments

...

Inputs or a list of inputs. NULL inputs are silently ignored.

Value

A list for cross_list() or tibble for cross_tbl(). Names will match the names of the inputs. Unnamed inputs will be left unnamed for cross_list() and automatically named for cross_tbl().

See also

cross_join() to find combinations of data frame rows.

purrr::cross() for an implementation that results in a differently formatted list.

expand.grid() for an implementation that results in a data.frame.

Examples

fruits   <- c("apple", "banana", "cantaloupe")
desserts <- c("cupcake", "muffin", "streudel")

cross_list(list(fruits, desserts))

#> [[1]]
#> [1] "apple"      "banana"     "cantaloupe" "apple"      "banana"    
#> [6] "cantaloupe" "apple"      "banana"     "cantaloupe"
#> 
#> [[2]]
#> [1] "cupcake"  "cupcake"  "cupcake"  "muffin"   "muffin"   "muffin"   "streudel"
#> [8] "streudel" "streudel"
#> 
cross_list(fruits, desserts)

#> [[1]]
#> [1] "apple"      "banana"     "cantaloupe" "apple"      "banana"    
#> [6] "cantaloupe" "apple"      "banana"     "cantaloupe"
#> 
#> [[2]]
#> [1] "cupcake"  "cupcake"  "cupcake"  "muffin"   "muffin"   "muffin"   "streudel"
#> [8] "streudel" "streudel"
#> 
cross_tbl(fruits, desserts)

#> New names:
#> * `` -> ...1
#> * `` -> ...2
#> # A tibble: 9 x 2
#>   ...1       ...2    
#>   <chr>      <chr>   
#> 1 apple      cupcake 
#> 2 banana     cupcake 
#> 3 cantaloupe cupcake 
#> 4 apple      muffin  
#> 5 banana     muffin  
#> 6 cantaloupe muffin  
#> 7 apple      streudel
#> 8 banana     streudel
#> 9 cantaloupe streudel

cross_list(list(fruit = fruits, dessert = desserts))

#> $fruit
#> [1] "apple"      "banana"     "cantaloupe" "apple"      "banana"    
#> [6] "cantaloupe" "apple"      "banana"     "cantaloupe"
#> 
#> $dessert
#> [1] "cupcake"  "cupcake"  "cupcake"  "muffin"   "muffin"   "muffin"   "streudel"
#> [8] "streudel" "streudel"
#> 
cross_list(fruit = fruits, dessert = desserts)

#> $fruit
#> [1] "apple"      "banana"     "cantaloupe" "apple"      "banana"    
#> [6] "cantaloupe" "apple"      "banana"     "cantaloupe"
#> 
#> $dessert
#> [1] "cupcake"  "cupcake"  "cupcake"  "muffin"   "muffin"   "muffin"   "streudel"
#> [8] "streudel" "streudel"
#> 
cross_tbl(fruit = fruits, dessert = desserts)

#> # A tibble: 9 x 2
#>   fruit      dessert 
#>   <chr>      <chr>   
#> 1 apple      cupcake 
#> 2 banana     cupcake 
#> 3 cantaloupe cupcake 
#> 4 apple      muffin  
#> 5 banana     muffin  
#> 6 cantaloupe muffin  
#> 7 apple      streudel
#> 8 banana     streudel
#> 9 cantaloupe streudel