def query_knn(self, location: np.ndarray, k: int) -> (np.ndarray, np.ndarray):
idx = h3.geo_to_h3(location[0], location[1], self.h3res)
i = 0
indices = np.zeros(0, dtype=np.uint64)
ring = np.zeros(0, dtype=np.uint64)
while indices.shape[0] < k:
i += 2
k_ring = h3.k_ring(idx, i)
ring = np.setdiff1d(k_ring, ring, assume_unique=True)
i0 = np.searchsorted(self.h3arr, ring, side='left', sorter=self.h3idx)
i1 = np.searchsorted(self.h3arr, ring, side='right', sorter=self.h3idx)
indices = np.hstack((indices,
np.hstack([np.arange(i, j, dtype=np.uint64)
for i, j in zip(i0, i1) if i != j])))
idx = self.h3idx[indices]
dist = gm.vec_haversine(self.locations[idx, 0],
self.locations[idx, 1],
location[0], location[1])
dist_idx = np.argsort(dist)
return idx[dist_idx[:k]], dist[dist_idx[:k]]
def true_parents(self) -> HexIdSet:
"""
hexagons do not cleanly subdivide into seven finer hexagons.
the child hexagon cells protrude from the parent (cf. https://h3geo.org/docs/highlights/indexing)
and hence a cell does not have a single, but actually up to 2 "true" parents
returns: the hex ids of all parent cells which any of the cell points belong
"""
if self.res == 0:
raise ValueError("not defined for resolution 0")
lower_res = self.res - 1
# NOTE: (lat,lng) pairs!
coord_pairs = h3.h3_to_geo_boundary(self.id)
return {h3.geo_to_h3(pt[0], pt[1], lower_res) for pt in coord_pairs}
def query_radius(self,
location: np.ndarray,
r: float) -> np.ndarray:
edge_len = h3.edge_length(self.h3res, unit="m")
idx = h3.geo_to_h3(location[0], location[1], self.h3res)
ring = h3.k_ring(idx, 1 + int(round(r / edge_len)))
i0 = np.searchsorted(self.h3arr, ring, side='left', sorter=self.h3idx)
i1 = np.searchsorted(self.h3arr, ring, side='right', sorter=self.h3idx)
indices = np.hstack([np.arange(i, j) for i, j in zip(i0, i1) if i != j])
idx = self.h3idx[indices]
dist = gm.vec_haversine(self.locations[idx, 0], self.locations[idx, 1],
location[0], location[1])
return self.h3idx[indices[np.argwhere(dist <= r).ravel()]]
def geo_to_h3_array(locations, resolution: int = 12):
hexes = [h3.geo_to_h3(locations[i, 0], locations[i, 1], resolution) for i in range(locations.shape[0])]
return hexes
def test1():
assert h3.geo_to_h3(37.7752702151959, -122.418307270836,
9) == 617700169958293503
def lies_in_h3_cell(h: int, lng: float, lat: float) -> bool:
res = h3.h3_get_resolution(h)
return h3.geo_to_h3(lat, lng, res) == h
def geo_to_h3(lng: float, lat: float) -> int:
return h3.geo_to_h3(lat, lng, SHORTCUT_H3_RES)