Converts a string of latitudes and longitudes into a square matrix to be
passed as a 'bbox' argument (to extract_osm_objects(), plot_osm_basemap (),
make_osm_map (), or extract_highway ()).
Usage
get_bbox(latlon)
Arguments
latlon
A vector of (longitude, latitude, longitude, latitude) values
Value
A 2-by-2 matrix of 4 elements with columns of min and max values, and
rows of x and y values.