For a map with n precincts Returns an n-by-n matrix, where each
entry measures the fraction of the plans in which the row and column
precincts were in the same district.
prec_cooccurrence(plans, which = NULL, sampled_only = TRUE, ncores = 1)a redist_plans object.
<data-masking> which plans to
compute the co-occurrence over. Defaults to all.
if TRUE, do not include reference plans.
the number of parallel cores to use in the computation.
a symmetric matrix the size of the number of precincts.