Vehicle registration plates — bkg

Retrieve motor vehicle registration plate regions in Germany. Registration plate regions are discerned by their area code (Unterscheidungszeichen) which indicate the place where a vehicle was registered. These regions partially overlap with districts but are not entirely identical.

This function interfaces the wfs_kfz250 product of the BKG.

Usage

bkg_kfz(
  ...,
  bbox = NULL,
  poly = NULL,
  predicate = "intersects",
  filter = NULL,
  epsg = 3035,
  properties = NULL,
  max = NULL
)

Arguments

...

Used to construct CQL filters. Dot arguments accept an R-like syntax that is converted to CQL queries internally. These queries basically consist of a property name on the left, an aribtrary vector on the right, and an operator that links both sides. If multiple queries are provided, they will be chained with AND. The following operators and their respective equivalents in CQL and XML are supported:

R	CQL	XML
`==`	`=`	`PropertyIsEqualTo`
`!=`	`<>`	`PropertyIsNotEqualTo`
`<`	`<`	`PropertyIsLessThan`
`>`	`>`	`PropertyIsGreaterThan`
`>=`	`>=`	`PropertyIsGreaterThanOrEqualTo`
`<=`	`<=`	`PropertyIsLessThanOrEqualTo`
`%LIKE%`	`LIKE`	`PropertyIsLike`
`%ILIKE%`	`ILIKE`
	`%in%`	`IN`

To construct more complex queries, you can use the filter argument to pass CQL queries directly. Also note that you can switch between CQL and XML queries using options(ffm_query_language = "xml"). See also wfs_filter.

bbox

An sf geometry or a boundary box vector of the format c(xmin, ymin, xmax, ymax). Used as a geometric filter to include only those geometries that relate to bbox according to the predicate specified in predicate. If an sf geometry is provided, coordinates are automatically transformed to ESPG:25832 (the default CRS), otherwise they are expected to be in EPSG:25832.

poly

An sf geometry. Used as a geometric filter to include only those geometries that relate to poly according to the predicate specified in predicate. Coordinates are automatically transformed to ESPG:25832 (the default CRS).

predicate

A spatial predicate that is used to relate the output geometries with the object specified in bbox or poly. For example, if predicate = "within", and bbox is specified, returns only those geometries that lie within bbox. Can be one of "equals", "disjoint", "intersects", "touches", "crosses", "within", "contains", "overlaps", "relate", "dwithin", or "beyond". Defaults to "intersects".

filter

A character string containing a valid CQL or XML filter. This string is appended to the query constructed through .... Use this argument to construct more complex filters. Defaults to NULL.

epsg

An EPSG code specifying a coordinate reference system of the output. If you're unsure what this means, try running sf::st_crs(...)$epsg on a spatial object that you are working with. Defaults to 3035.

properties

Vector of columns to include in the output.

max

Maximum number of results to return.

Value

An sf dataframe with multipolygon geometries and the following columns:

debkgid: Identifier in the digital landscape model DLM250
nnid: National name identifier
name: Name of the geographical object
ars: Territorial code (Amtlicher Regionalschlu00fcssel). The ARS is stuctured hierarchically as follows:
- Position 1-2: Federal state
- Position 3: Government region
- Position 4-5: District
- Position 6-9: Administrative association
- Position 10-12: Municipality
oba: Name of the ATKIS object type
kfz: Vehicle registration area code, comma-separated in case of multiple codes
geola: Geographical longitude
geobr: Geographical latitude
gkre: Gauu00df-Kru00fcger easting
gkho: Gauu00df-Kru00fcger northing
utmre: UTM easting
utmho: UTM northing

Examples

if (FALSE) { # getFromNamespace("ffm_run_examples", ns = "ffm")() && requireNamespace("ggplot2")
library(ggplot2)

kfz <- bkg_kfz(ars %LIKE% "053%")
ggplot(kfz) +
  geom_sf(fill = NA) +
  geom_sf_text(aes(label = kfz)) +
  theme_void()
}