Get borders between polygons.
mf_get_borders(x, id)Arguments
- x
an sf object of POLYGONS, using a projected CRS.
- id
name of the identifier variable in x, default to the first column. (optional)
Value
An sf object (MULTILINESTRING) of borders is returned. This object has three id variables: id, id1 and id2. id1 and id2 are ids of units that neighbor a border; id is the concatenation of id1 and id2 (with "_" as separator).
Examples
mtq <- mf_get_mtq()
# Extract 3 polygons
m <- mtq[c(5, 29, 9), ]
# Get borders
m_borders <- mf_get_borders(x = m)
# Plot polygons
mf_map(m)
# Plot borders
mf_map(m_borders,
col = 1:4, lwd = c(8, 6, 4, 2),
add = TRUE
)
# Plot labels
mf_label(m_borders, "id",
overlap = FALSE,
lines = FALSE, halo = TRUE,
col = 1:4
)
