Build an Overpass query

opq(bbox = NULL, timeout = 25, memsize)

Arguments

bbox

Either (i) four numeric values specifying the maximal and minimal longitudes and latitudes, in the form c(xmin, ymin, xmax, ymax) or (ii) a character string in the form xmin,ymin,xmax,ymax. These will be passed to getbb to be converted to a numerical bounding box. Can also be (iii) a matrix representing a bounding polygon as returned from getbb(..., format_out = "polygon").

timeout

It may be necessary to increase this value for large queries, because the server may time out before all data are delivered.

memsize

The default memory size for the 'overpass' server in bytes; may need to be increased in order to handle large queries.

Value

An overpass_query object

Note

See https://wiki.openstreetmap.org/wiki/Overpass_API#Resource_management_options_.28osm-script.29 for explanation of timeout and memsize (or maxsize in overpass terms). Note in particular the comment that queries with arbitrarily large memsize are likely to be rejected.

Examples

if (FALSE) { q <- getbb ("portsmouth", display_name_contains = "USA") %>% opq () %>% add_osm_feature("amenity", "restaurant") %>% add_osm_feature("amenity", "pub") osmdata_sf (q) # all objects that are restaurants AND pubs (there are none!) q1 <- getbb ("portsmouth", display_name_contains = "USA") %>% opq () %>% add_osm_feature("amenity", "restaurant") q2 <- getbb ("portsmouth", display_name_contains = "USA") %>% opq () %>% add_osm_feature("amenity", "pub") c (osmdata_sf (q1), osmdata_sf (q2)) # all objects that are restaurants OR pubs }