Determines the set of elements, distributed in clusters, that are
contiguous to an element from another cluster.
Usage
interior_boundary(contiguity, partition, removeSymmetry = TRUE)
Arguments
- contiguity
A contiguity matrix or a contiguity graph
(package igraph). Prefer matrix is possible.
(contiguity matrix or igraph graph)
- partition
The partition. (vector of strictly positive integers)
- removeSymmetry
TRUE (default) if symmetry should be removed
from the result. (flag)
Value
a matrix with 4 columns (x1, x2, cluster1, cluster2) with
as many rows as possible connections between an element of a cluster and
another. If removeSymmetry = TRUE, only rows where x1 < x2 are kept.
Details
The interior boundary of a partition, under a certain
contiguity, is defined as the set of elements contiguous to at least
one other element from a different cluster than its own.
