Downloads municipal boundaries automatically, groups by county-to-region
mapping, derives parameters via Analytical Results 1-2, and returns an
exploded_map S3 object.
Usage
explode_state(
state_fips,
crs,
region_map,
gamma_r = 3,
gamma_l = 1.136,
p = 1.25,
alpha_r = NULL,
alpha_l = NULL,
refine = FALSE,
refine_min_gap = NULL,
refine_max_shift = NULL,
refine_max_iter = 20,
refine_step = 0.5,
refine_within = c("region", "all"),
allow_other = FALSE,
fix_invalid = TRUE,
centroid_fun = c("centroid", "point_on_surface"),
plot = TRUE,
export = NULL,
label = paste0("FIPS ", state_fips)
)Arguments
- state_fips
2-digit FIPS code (e.g. "34" for NJ)
- crs
Projected CRS EPSG code (metric units)
- region_map
Named list: region_name -> character vector of county names
- gamma_r
Regional clearance coefficient (default 3.0)
- gamma_l
Local clearance coefficient (default 1.136)
- p
Distance scaling exponent (default 1.25)
- alpha_r
Optional manual override for regional separation (metres). May be supplied independently of
alpha_l.- alpha_l
Optional manual override for local expansion (metres). May be supplied independently of
alpha_r.- refine
If TRUE, apply a bounded collision-refinement pass after the analytical displacement. Default is FALSE.
- refine_min_gap
Optional minimum boundary-to-boundary gap in map units. If NULL and
refine = TRUE, uses 2% of the characteristic diameter.- refine_max_shift
Optional maximum correction per feature in map units. If NULL and
refine = TRUE, uses 10% ofalpha_r + alpha_l.- refine_max_iter
Maximum refinement iterations.
- refine_step
Fraction of each gap deficit corrected per iteration.
- refine_within
Refine pairs within each
"region"(default) or across"all"features.- allow_other
If TRUE, permits units mapped to "Other"
- fix_invalid
If TRUE, auto-repairs invalid geometries
- centroid_fun
"centroid" (default) or "point_on_surface"
- plot
Print plots on return (default TRUE)
- export
NULL (no export), TRUE (auto-named GeoJSON), or a file path
- label
Title for plots and print output