vapour_layer_extent {vapour}

Read layer extent

Description

Extent of all features in entire layer, possibly after execution of sql query and input extent filter.

Usage

vapour_layer_extent(dsource, layer = 0L, sql = "", extent = 0, ...)

Arguments

dsource

data source name (path to file, connection string, URL)

layer

integer of layer to work with, defaults to the first (0) or the name of the layer

sql

if not empty this is executed against the data source (layer will be ignored)

extent

optional extent (xmin,xmax,ymin,ymax)

...

unused

Value

vector of numeric values xmin,xmax,ymin,ymax

See Also

vapour_read_extent vapour_layer_info

Examples

file <- "list_locality_postcode_meander_valley.tab"
## A MapInfo TAB file with polygons
mvfile <- system.file(file.path("extdata/tab", file), package="vapour")
vapour_layer_extent(mvfile)