def test_geokeys():
"Test geo hash keys returned for various coordinates."
init_geohash(_GHKEYLENGTH, _SCALEFACTOR)
expected = [
(0.0, 0.0, 's0000'),
(89, 0.0, 'upb42'),
(89.999999999999992, 0.0, 'upbpb'), # Max lat supported.
(-90, 0.0, 'h0000'),
(-90, -180, '00000'),
(-90, +180, '00000'),
(-90, +90, 'n0000'),
(-90, -90, '40000'),
(-45, -45, '70000'),
(-45, 45, 'm0000'),
(45, 45, 'v0000'),
(45, -45, 'g0000')
]
for (lat, lon, ghkey) in expected:
elem = new_osm_element(C.NODE, '0')
elem[C.LAT] = lat * _SCALEFACTOR
elem[C.LON] = lon * _SCALEFACTOR
res = geohash_key_for_element(elem)
assert res == ghkey
def add(self, elem):
'''Add information about a node 'elem' to the geo table.
Usage:
>>> gt = GeoGroupTable()
>>> gt = gt.add(elem)
The node 'elem' should have a 'lat' and 'lon' fields that
encode its latitude and longitude respectively. The 'id'
field specifies the node's "id".
'''
assert elem.namespace == C.NODE, "elem is not a node: %s" % str(elem)
# Determine the geo-key for the node.
ghkey = geohash_key_for_element(elem)
# Retrieve the partition covering this location.
ghdoc = self.geodb[ghkey]
elemid = elem.id
if elemid not in ghdoc:
ghdoc.add(elem)
self.lru[ghkey] = ghdoc
