14.6 Example: Poland 2015 Election

pol_pres15 |>
    subset(select = c(TERYT, name, types)) |>
    head()

## Simple feature collection with 6 features and 3 fields
## Geometry type: MULTIPOLYGON
## Dimension:     XY
## Bounding box:  xmin: 235157.1 ymin: 366913.3 xmax: 281431.7 ymax: 413016.6
## Projected CRS: ETRS89 / Poland CS92
##    TERYT                name       types                       geometry
## 1 020101         BOLESŁAWIEC       Urban MULTIPOLYGON (((261089.5 38...
## 2 020102         BOLESŁAWIEC       Rural MULTIPOLYGON (((254150 3837...
## 3 020103            GROMADKA       Rural MULTIPOLYGON (((275346 3846...
## 4 020104        NOWOGRODZIEC Urban/rural MULTIPOLYGON (((251769.8 37...
## 5 020105          OSIECZNICA       Rural MULTIPOLYGON (((263423.9 40...
## 6 020106 WARTA BOLESŁAWIECKA       Rural MULTIPOLYGON (((267030.7 38...

# tmap
tm_shape(pol_pres15) + tm_fill("types")

For safety’s sake, we impose topological validity:

if (!all(st_is_valid(pol_pres15)))
        pol_pres15 <- st_make_valid(pol_pres15)