def _nearest(self, geom, exclusive):
envelope = geom.envelope
def callback(item1, item2, distance, userdata):
try:
callback_userdata = ctypes.cast(userdata,
ctypes.py_object).value
idx = ctypes.cast(item1, ctypes.py_object).value
geom2 = ctypes.cast(item2, ctypes.py_object).value
dist = ctypes.cast(distance, ctypes.POINTER(ctypes.c_double))
if callback_userdata["exclusive"] and self._geoms[idx].equals(
geom2):
dist[0] = sys.float_info.max
else:
lgeos.GEOSDistance(self._geoms[idx]._geom, geom2._geom,
dist)
return 1
except Exception:
log.exception("Caught exception")
return 0
item = lgeos.GEOSSTRtree_nearest_generic(
self._tree,
ctypes.py_object(geom),
envelope._geom,
lgeos.GEOSDistanceCallback(callback),
ctypes.py_object({"exclusive": exclusive}),
)
return ctypes.cast(item, ctypes.py_object).value
def nearest(self, geom):
"""
Get the nearest object in the index to a geometry object.
Parameters
----------
geom : geometry object
The query geometry
Returns
-------
geometry object
The nearest geometry object in the index to `geom`.
Will always only return *one* object even if several
in the index are the minimum distance away.
`None` if the index is empty.
Examples
--------
>>> from shapely.strtree import STRtree
>>> from shapely.geometry import Point
>>> tree = STRtree([Point(i, i) for i in range(10)])
>>> tree.nearest(Point(2.2, 2.2)).wkt
'POINT (2 2)'
Will only return one object:
>>> tree = STRtree ([Point(0, 0), Point(0, 0)])
>>> tree.nearest(Point(0, 0)).wkt
'POINT (0 0)'
"""
if self._n_geoms == 0:
return None
envelope = geom.envelope
def callback(item1, item2, distance, userdata):
try:
geom1 = ctypes.cast(item1, ctypes.py_object).value
geom2 = ctypes.cast(item2, ctypes.py_object).value
dist = ctypes.cast(distance, ctypes.POINTER(ctypes.c_double))
lgeos.GEOSDistance(geom1._geom, geom2._geom, dist)
return 1
except Exception:
return 0
item = lgeos.GEOSSTRtree_nearest_generic(self._tree_handle, ctypes.py_object(geom), envelope._geom, \
lgeos.GEOSDistanceCallback(callback), None)
result = ctypes.cast(item, ctypes.py_object).value
return result
def nearest(self, geom):
if self._n_geoms == 0:
return None
envelope = geom.envelope
def callback(item1, item2, distance, userdata):
try:
geom1 = ctypes.cast(item1, ctypes.py_object).value
geom2 = ctypes.cast(item2, ctypes.py_object).value
dist = ctypes.cast(distance, ctypes.POINTER(ctypes.c_double))
lgeos.GEOSDistance(geom1._geom, geom2._geom, dist)
return 1
except:
return 0
item = lgeos.GEOSSTRtree_nearest_generic(self._tree_handle, ctypes.py_object(geom), envelope._geom, \
lgeos.GEOSDistanceCallback(callback), None)
result = ctypes.cast(item, ctypes.py_object).value
return result
