Specify the units to cross to index a new unit

crossed_by(A, B) is the same as ~A:B but crossed_by offers more control over the names of the new units as well as adding new attributes.

Usage

crossed_by(..., attrs = NULL)

Arguments

...

a sequence of units

attrs

Currently not implemented.

Value

An object of class "cross_lvls".

Examples

design("Strip-Plot Design | Strip-Unit Design") %>%
  set_units(block = 3,
            row = nested_in(block, 7),
            col = nested_in(block, 6),
            unit = nested_in(block, crossed_by(row, col)))
#> Strip-Plot Design | Strip-Unit Design
#> └─block (3 levels)
#>   ├─row (21 levels)
#>   │ └─unit (126 levels)
#>   ├─col (18 levels)
#>   │ └─unit (126 levels)
#>   └─unit (126 levels)