Supra-Adjacency Matrix — supra_adjacency • cograph

Builds the supra-adjacency matrix for multilayer networks. Diagonal blocks = intra-layer, off-diagonal = inter-layer.

Usage

supra_adjacency(
  layers,
  omega = 1,
  coupling = c("diagonal", "full", "custom"),
  interlayer_matrices = NULL
)

supra(
  layers,
  omega = 1,
  coupling = c("diagonal", "full", "custom"),
  interlayer_matrices = NULL
)

Arguments

layers

List of adjacency matrices (same dimensions)

omega

Inter-layer coupling coefficient (scalar or L x L matrix)

coupling

Coupling type: "diagonal", "full", or "custom"

interlayer_matrices

For coupling = "custom", a list of inter-layer matrices. Accepted shapes:

Named list with keys "a_b" (integer layer indices) or "<layer_name_a>_<layer_name_b>"; either order works.
Unnamed list of length choose(L, 2) giving every pair in upper-triangle row-major order: (1,2), (1,3), ..., (1,L), (2,3), ..., (L-1,L).
Unnamed list of length L-1 giving adjacent pairs only (legacy chain layout): entry i is the coupling for (i, i+1). Non-adjacent pairs use omega[a,b] * I.

If no entry matches a pair and no legacy chain layout applies, a warning is emitted and the diagonal default omega[a,b] * I is used (previously this happened silently).

Value

Supra-adjacency matrix of dimension (NL) x (NL)

Examples

# layers <- list(L1 = mat1, L2 = mat2)
# S <- supra_adjacency(layers, omega = 0.5)
# dim(S)  # (2*n) x (2*n)