Query Row Correspondence in a Hyperdesign

A correspondence object describes how local rows in each hyperdesign block map to a global entity universe. Correspondence is opt-in: construct the hyperdesign with either `id` or `positional = TRUE`.

Usage

correspondence(x, ...)

# S3 method for class 'hyperdesign'
correspondence(x, sort_ids = FALSE, ...)

Arguments

x

A hyperdesign object.

...

Additional arguments passed to methods.

sort_ids

Logical; if `TRUE`, order normalized global identifiers with base R radix ordering. The default preserves first-seen order.

Value

For a contracted hyperdesign, a `md_correspondence` list containing the declared key, assumption, global identifiers, local identifiers, integer row maps, incidence matrix, pairwise overlap counts, and block connectivity flag.

Details

Explicit identifiers are compared through a common character representation, so integer `1` and character `"1"` match. `global_ids` follows first-seen block and row order, and each integer `row_map` indexes that vector. Missing values in the data matrix are ordinary data and are never interpreted as a correspondence mask.

Examples

a <- multidesign(matrix(1:6, ncol = 2), data.frame(id = c("B", "A", "C")))
b <- multidesign(matrix(7:10, ncol = 2), data.frame(id = c("A", "D")))
hd <- hyperdesign(list(a = a, b = b), id = "id", space = "common")
correspondence(hd)$global_ids
#> [1] "B" "A" "C" "D"
correspondence(hd, sort_ids = TRUE)$global_ids
#> [1] "A" "B" "C" "D"