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Dissolve data

Source: R/wdpa_dissolve.R
wdpa_dissolve.Rd

Create a dataset of spatial boundaries that contains no overlapping geometries.

Usage

wdpa_dissolve(x, geometry_precision = 1500)

Arguments

x

sf::sf() object.

geometry_precision

numeric level of precision for processing the spatial data (used with sf::st_set_precision()). The default argument is 1500 (higher values indicate higher precision). This level of precision is generally suitable for analyses at the national-scale. For analyses at finer-scale resolutions, please consider using a greater value (e.g. 10000).

Value

A sf::sf() object.

Details

This function is basically a wrapper for sf::st_union(). It also contains additional parameters to assist with processing large and complex geometry data.

See also

sf::st_union(), st_erase_overlaps().

Examples

# create data
pl1 <- sf::st_polygon(list(matrix(c(0, 0, 2, 0, 1, 1, 0, 0), byrow = TRUE,
                                  ncol = 2))) * 100
pl2 <- sf::st_polygon(list(matrix(c(0, 0.5, 2, 0.5, 1, 1.5, 0, 0.5),
                                  byrow = TRUE, ncol = 2))) * 100
pl3 <- sf::st_polygon(list(matrix(c(0, 1.25, 2, 1.25, 1, 2.5, 0, 1.25),
                                  byrow = TRUE, ncol = 2))) * 100
x <- sf::st_sf(order = c("A", "B", "C"),
               geometry = sf::st_sfc(list(pl1, pl2, pl3), crs = 3395))

# dissolve data
y <- wdpa_dissolve(x)

# plot data for visual comparison
par(mfrow = c(1, 2))
plot(sf::st_geometry(x), xlim = c(0, 200), ylim = c(0, 250),
     main = "original", col = "transparent")
plot(sf::st_geometry(y), , xlim = c(0, 200), ylim = c(0, 250),
     main = "dissolved", col = "transparent")