Generates voronoi polygons by first performing stratified sampling across boundary polygons, then by running the voronoisation with st_voronoi().

tesselate_voronoi(
  boundaries,
  with,
  boundary = "sfa",
  sample_surface = FALSE,
  sample_points = TRUE,
  nb_samples = NULL,
  min_size = 1500,
  stratify = TRUE,
  seed = 1
)

Arguments

boundaries

[sf] The boundaries to be used.

with

[sf] A set of data points to use for voronoisation.

boundary

[character] The column in boundaries that is to be used for the stratified sampling.

sample_surface

[logical] Whether to sample the surfaces in boundaries, Default to FALSE.

sample_points

[logical] Whether to sample points from with or to take all points in with. Default to TRUE.

nb_samples

[named character vector] The number of samples to draw by boundary polygons (must bear the levels of boundary as names or be a single value to be applied to each level).

min_size

[numeric] The minimum size for a polygon above which it will be merged (in km2).

stratify

[logical] Whether the discretization happens within the boundaries or whether the whole area is to be used (default to TRUE).

seed

[numeric] Passed onto set.seed(), important for reproducibility of sampling.

Value

A named list with three elements (each an sf object): * patches, the voronoi polygons generated * points, the points used for the tessellation.

Examples

data(borealis_simulated, package = "sspm")
data(sfa_boundaries, package = "sspm")
tesselate_voronoi(sfa_boundaries, with = borealis, sample_surface = TRUE,
                  boundary = "sfa", nb_samples = 10)
#> $patches
#> Simple feature collection with 39 features and 3 fields
#> Geometry type: POLYGON
#> Dimension:     XY
#> Bounding box:  xmin: -64.18658 ymin: 46.00004 xmax: -46.6269 ymax: 60.84469
#> Geodetic CRS:  WGS 84
#> # A tibble: 39 × 4
#>    sfa   patch_id patch_area                                            geometry
#>  * <chr> <fct>        [km^2]                                       <POLYGON [°]>
#>  1 4     P1            4945. ((-63.30252 59.8266, -61.99686 60.78698, -61.99048…
#>  2 4     P2            4319. ((-60.3537 59.58289, -60.72773 58.94674, -60.59988…
#>  3 4     P3            8328. ((-62.41861 58.76298, -61.87269 60.47405, -61.9968…
#>  4 4     P4            3904. ((-61.99048 60.84469, -61.99686 60.78698, -61.8726…
#>  5 4     P5            8916. ((-60.91758 57.68787, -60.93575 57.69861, -60.9357…
#>  6 4     P6            5286. ((-62.22483 58.58756, -61.71019 59.02802, -61.5420…
#>  7 4     P7            3228. ((-61.39129 59.18604, -60.77284 59.86003, -61.5420…
#>  8 4     P8            3312. ((-60.54774 59.91234, -60.77284 59.86003, -61.3912…
#>  9 4     P9            5337. ((-60.18751 57.68945, -60.17467 57.68869, -60.1741…
#> 10 5     P10          11209. ((-59.07859 55.37257, -58.945 55.46567, -58.58355 …
#> # … with 29 more rows
#> 
#> $points
#> Simple feature collection with 40 features and 1 field
#> Geometry type: POINT
#> Dimension:     XY
#> Bounding box:  xmin: -62.90629 ymin: 46.20124 xmax: -47.38968 ymax: 60.62645
#> Geodetic CRS:  WGS 84
#> First 10 features:
#>    sfa                   geometry
#> 1    4 POINT (-62.90629 60.62645)
#> 2    4 POINT (-61.42425 59.70269)
#> 3    4 POINT (-59.80715 58.04987)
#> 4    4  POINT (-59.6313 57.70734)
#> 5    4 POINT (-61.00018 58.84686)
#> 6    4 POINT (-61.15296 60.41194)
#> 7    4 POINT (-60.87372 59.19752)
#> 8    4 POINT (-61.78665 59.75678)
#> 9    4 POINT (-62.35403 59.93536)
#> 10   4  POINT (-60.4377 58.93765)
#>