Coverage for pygeodesy/geohash.py: 97%

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1 

2# -*- coding: utf-8 -*- 

3 

4u'''I{Gustavo Niemeyer}’s U{Geohash<https://WikiPedia.org/wiki/Geohash>}. 

5 

6Class L{Geohash} and several functions to encode, decode and inspect 

7C{geohashes} and optional L{Geohashed} caches. 

8 

9Originally transcoded from JavaScript originals by I{(C) Chris Veness 

102011-2024} and published under the same MIT Licence**, see 

11U{Geohashes<https://www.Movable-Type.co.UK/scripts/geohash.html>}. 

12 

13@see: U{Geohash<https://WikiPedia.org/wiki/Geohash>}, I{Karney}'s C++ 

14 U{Geohash<https://GeographicLib.SourceForge.io/C++/doc/classGeographicLib_1_1Geohash.html>}, 

15 U{geohash<https://GitHub.com/vinsci/geohash>}, 

16 U{pygeohash<https://PyPI.org/project/pygeohash>} and 

17 U{geohash-js<https://GitHub.com/DaveTroy/geohash-js>}. 

18''' 

19 

20from pygeodesy.basics import isstr, map2, _splituple 

21from pygeodesy.constants import EPS, R_M, _0_0, _0_5, _180_0, _360_0, \ 

22 _90_0, _N_90_0, _N_180_0 # PYCHOK used! 

23from pygeodesy.errors import _ValueError, _xkwds, _xStrError 

24# from pygeodesy import formy as _formy # _MODS.into 

25from pygeodesy.interns import NN, _DMAIN_, _DOT_, _E_, _height_, _N_, _NE_, \ 

26 _NW_, _radius_, _S_, _SE_, _SW_, _W_, _width_ # _INV_ 

27from pygeodesy.lazily import _ALL_DOCS, _ALL_LAZY, _ALL_MODS as _MODS 

28from pygeodesy.named import _name__, _NamedDict, _NamedTuple, nameof, _xnamed 

29from pygeodesy.namedTuples import Bounds2Tuple, Bounds4Tuple, LatLon2Tuple, \ 

30 PhiLam2Tuple 

31from pygeodesy.props import deprecated_function, deprecated_method, \ 

32 deprecated_property_RO, Property_RO, \ 

33 property_RO, property_ROver 

34# from pygeodesy.streprs import Fmt, fstr # _MODS 

35from pygeodesy.units import Degrees_, Int, Lat_, Lon_, Meter, Precision_, Str 

36 

37from math import fabs, ldexp, log10, radians 

38 

39__all__ = _ALL_LAZY.geohash 

40__version__ = '25.04.21' 

41 

42_formy = _MODS.into(formy=__name__) 

43_MASK5 = 16, 8, 4, 2, 1 # PYCHOK used! 

44_MaxPrec = 12 

45 

46 

47def _2bounds(LatLon, LatLon_kwds, s, w, n, e, **name): 

48 '''(INTERNAL) Return SW and NE bounds. 

49 ''' 

50 if LatLon is None: 

51 r = Bounds4Tuple(s, w, n, e, **name) 

52 else: 

53 kwds = _xkwds(LatLon_kwds, **name) 

54 r = Bounds2Tuple(LatLon(s, w, **kwds), 

55 LatLon(n, e, **kwds), **name) 

56 return r 

57 

58 

59def _2center(bounds): 

60 '''(INTERNAL) Return the C{bounds} center. 

61 ''' 

62 return (_2mid(bounds.latN, bounds.latS), 

63 _2mid(bounds.lonE, bounds.lonW)) 

64 

65 

66def _2dab(d, a, b): 

67 '''(INTERNAL) Get delta lat or lon from center. 

68 ''' 

69 return fabs(d - round(*_2mid_ndigits(a, b))) 

70 

71 

72def _2fll(lat, lon, *unused): 

73 '''(INTERNAL) Convert lat, lon to 2-tuple of floats. 

74 ''' 

75 # lat, lon = parseDMS2(lat, lon) 

76 return (Lat_(lat, Error=GeohashError), 

77 Lon_(lon, Error=GeohashError)) 

78 

79 

80def _2Geohash(geohash): 

81 '''(INTERNAL) Check or create a Geohash instance. 

82 ''' 

83 return geohash if isinstance(geohash, Geohash) else \ 

84 Geohash(geohash) 

85 

86 

87def _2latlon(s, w, n, e, fstr=None): 

88 '''(INTERNAL) Get the center C{lat, lon}, rounded. 

89 ''' 

90 lat, a = _2mid_ndigits(n, s) 

91 lon, b = _2mid_ndigits(e, w) 

92 return (fstr(lat, prec=a), fstr(lon, prec=b)) if fstr else \ 

93 (round(lat, a), round(lon, b)) 

94 

95 

96def _2mid(a, b): 

97 '''(INTERNAL) Bisect C{a} to C{b}. 

98 ''' 

99 return (a + b) * _0_5 # favg 

100 

101 

102def _2mid_ndigits(a, b): # a > b 

103 '''(INTERNAL) Return 2-tuple C{(_2mid, ndigits)}. 

104 ''' 

105 # round to near centre without excessive 

106 # precision to ⌊2-log10(Δ°)⌋ ndigits 

107 return _2mid(a, b), int(2 - log10(a - b)) 

108 

109 

110def _2Precision(p): 

111 '''(INTERNAL) Get a valid C{Precision}. 

112 ''' 

113 return Precision_(p, low=1, high=_MaxPrec, Error=GeohashError) 

114 

115 

116def _2res(res, **prec): 

117 '''(INTERNAL) Get the C{res}olution for a C{prec}ision. 

118 ''' 

119 p = max(min(Int(Error=GeohashError, **prec), _MaxPrec), 0) * 5 

120 x = (p - p // 2) if res > _180_0 else (p // 2) 

121 return ldexp(res, -x) if x else res # ldexp == res / float(1 << x) 

122 

123 

124class _GH(object): 

125 '''(INTERNAL) Lazily defined constants. 

126 ''' 

127 def _4d(self, s, w, n, e): # helper 

128 return dict(S=(s, w), W=(w, s), 

129 N=(n, e), E=(e, n)) 

130 

131 @property_ROver 

132 def Borders(self): 

133 return self._4d('028b', '0145hjnp', 'prxz', 'bcfguvyz') 

134 

135 @property_ROver 

136 def DecodeB32(self): # inverse EncodeB32 map 

137 return dict((c, i) for i, c in enumerate(self.EncodeB32)) 

138 

139 def decode2(self, geohash): 

140 '''Decode C{geohash} to 2-tuple C{(lat, lon)}. 

141 ''' 

142 swne = self.swne4(geohash) 

143 return _2latlon(*swne) 

144 

145 # Geohash's base32 codes, no a, i, l and o 

146 EncodeB32 = '0123456789bcdefghjkmnpqrstuvwxyz' 

147 

148 def encode(self, *lat_lon_prec_eps): 

149 '''Encode C{lat, lon} to C{prec}ision or C{eps}. 

150 ''' 

151 def _encodes(lat, lon, prec, eps=0): 

152 s, w, n, e = self.SWNE4 

153 E, d, _mid = self.EncodeB32, True, _2mid 

154 for _ in range(prec): 

155 i = 0 

156 for _ in range(5): # len(_MASK5) 

157 i += i 

158 if d: # bisect longitude 

159 a = _mid(e, w) 

160 if lon < a: 

161 e = a 

162 else: 

163 w = a 

164 i += 1 

165 else: # bisect latitude 

166 a = _mid(n, s) 

167 if lat < a: 

168 n = a 

169 else: 

170 s = a 

171 i += 1 

172 d = not d 

173 yield E[i] 

174 if eps > 0: # infer prec 

175 if _2dab(lon, e, w) < eps and \ 

176 _2dab(lat, n, s) < eps: 

177 break 

178 

179 return NN.join(_encodes(*lat_lon_prec_eps)) 

180 

181 def encode2(self, lat, lon, prec, eps): 

182 '''Return 2-tuple C{geohash, (lat, lon))}. 

183 ''' 

184 lat, lon = _2fll(lat, lon) 

185 if prec: 

186 p, e = _2Precision(prec), 0 

187 else: # infer precision by refining geohash 

188 p, e = _MaxPrec, max(eps, EPS) 

189 return self.encode(lat, lon, p, e), (lat, lon) 

190 

191 @property_ROver 

192 def _LatLon2Tuple(self): 

193 

194 class _LatLon2Tuple(_NamedTuple): 

195 '''DEPRECATED on 2024.07.28, C{(lat, lon)} in B{C{meter}}, use L{Sizes3Tuple}.''' 

196 _Names_ = LatLon2Tuple._Names_ 

197 _Units_ = Meter, Meter 

198 

199 return _LatLon2Tuple 

200 

201 @property_ROver 

202 def Neighbors(self): 

203 return self._4d('14365h7k9dcfesgujnmqp0r2twvyx8zb', 

204 '238967debc01fg45kmstqrwxuvhjyznp', 

205 'p0r21436x8zb9dcf5h7kjnmqesgutwvy', 

206 'bc01fg45238967deuvhjyznpkmstqrwx') 

207 

208 @property_ROver 

209 def Sizes(self): # height, width and radius (in meter) 

210 # where radius = sqrt(height * width / PI), the 

211 # radius of a circle with area (height * width) 

212 T = Sizes3Tuple 

213 return (T(20000e3, 20032e3, 11292815.096), # 0 

214 T( 5000e3, 5003e3, 2821794.075), # 1 

215 T( 650e3, 1225e3, 503442.397), # 2 

216 T( 156e3, 156e3, 88013.575), # 3 

217 T( 19500, 39100, 15578.683), # 4 

218 T( 4890, 4890, 2758.887), # 5 

219 T( 610, 1220, 486.710), # 6 

220 T( 153, 153, 86.321), # 7 

221 T( 19.1, 38.2, 15.239), # 8 

222 T( 4.77, 4.77, 2.691), # 9 

223 T( 0.596, 1.19, 0.475), # 10 

224 T( 0.149, 0.149, 0.084), # 11 

225 T( 0.0186, 0.0372, 0.015)) # 12 _MaxPrec 

226 

227 SWNE4 = (_N_90_0, _N_180_0, _90_0, _180_0) 

228 

229 def swne4(self, geohash, mask5=_MASK5): 

230 '''Decode C{geohash} into 4-tuple C{(s, w, n, e)}. 

231 ''' 

232 nc = len(geohash) if isstr(geohash) else 0 

233 if not (0 < nc <= _MaxPrec): # or geohash.startswith(_INV_) 

234 raise GeohashError(geohash=geohash, len=nc) 

235 s, w, n, e = self.SWNE4 

236 D, d, _mid = self.DecodeB32, True, _2mid 

237 try: 

238 for j, c in enumerate(geohash.lower()): 

239 i = D[c] 

240 for m in mask5: 

241 if d: # longitude 

242 a = _mid(e, w) 

243 if (i & m): 

244 w = a 

245 else: 

246 e = a 

247 else: # latitude 

248 a = _mid(n, s) 

249 if (i & m): 

250 s = a 

251 else: 

252 n = a 

253 d = not d 

254 except KeyError: 

255 c = _MODS.streprs.Fmt.INDEX(repr(c), j) 

256 raise GeohashError(geohash=geohash, len=nc, txt=c) 

257 return s, w, n, e 

258 

259_GH = _GH() # PYCHOK singleton 

260 

261 

262class Geohash(Str): 

263 '''Geohash class, a named C{str}. 

264 ''' 

265 # no str.__init__ in Python 3 

266 def __new__(cls, lat_ghll, lon=None, precision=None, eps=EPS, **name): 

267 '''New L{Geohash} from an other L{Geohash} instance or geohash C{str} 

268 or from a lat- and longitude. 

269 

270 @arg lat_ghll: Latitude (C{degrees90}), a geohash (L{Geohash}, 

271 C{str}) or a location (C{LatLon}, C{LatLon*Tuple}). 

272 @kwarg lon: Logitude (C{degrees180)}, required if B{C{lat_ghll}} 

273 is C{degrees90}, ignored otherwise. 

274 @kwarg precision: The desired geohash length (C{int} 1..12) or 

275 C{None} or C{0}, see L{encode<pygeodesy.geohash.encode>}. 

276 @kwarg eps: Optional inference tolerance (C{degrees}), see 

277 L{encode<pygeodesy.geohash.encode>}. 

278 @kwarg name: Optional C{B{name}=NN} (C{str}). 

279 

280 @return: New L{Geohash}. 

281 

282 @raise GeohashError: Invalid B{C{lat_ghll}}. 

283 

284 @raise RangeError: Invalid B{C{lat_gll}} or B{C{lon}}. 

285 

286 @raise TypeError: Invalid B{C{lat_ghll}}. 

287 ''' 

288 if lon is None: 

289 if isinstance(lat_ghll, Geohash): 

290 gh, ll = str(lat_ghll), lat_ghll.latlon 

291 elif isstr(lat_ghll): # "lat, lon" or "geohash" 

292 ll = _splituple(lat_ghll) 

293 if len(ll) > 1: 

294 gh, ll = _GH.encode2(ll[0], ll[1], precision, eps) 

295 else: 

296 gh, ll = lat_ghll.lower(), None 

297 _ = _GH.swne4(gh, mask5=()) # validate 

298 else: # assume LatLon 

299 try: 

300 gh, ll = _GH.encode2(lat_ghll.lat, lat_ghll.lon, precision, eps) 

301 except AttributeError: 

302 raise _xStrError(Geohash, ghll=lat_ghll, Error=GeohashError) 

303 else: 

304 gh, ll = _GH.encode2(lat_ghll, lon, precision, eps) 

305 

306 self = Str.__new__(cls, gh, name=_name__(name, _or_nameof=lat_ghll)) 

307 self._latlon = ll 

308 return self 

309 

310 @deprecated_property_RO 

311 def ab(self): 

312 '''DEPRECATED, use property C{philam}.''' 

313 return self.philam 

314 

315 def adjacent(self, direction, **name): 

316 '''Determine the adjacent cell in the given compass direction. 

317 

318 @arg direction: Compass direction ('N', 'S', 'E' or 'W'). 

319 @kwarg name: Optional C{B{name}=NN} (C{str}) otherwise this 

320 cell's name, either extended with C{.D}irection. 

321 

322 @return: Geohash of adjacent cell (L{Geohash}). 

323 

324 @raise GeohashError: Invalid geohash or B{C{direction}}. 

325 ''' 

326 # based on <https://GitHub.com/DaveTroy/geohash-js> 

327 

328 D = direction[:1].upper() 

329 if D not in _GH.Neighbors: 

330 raise GeohashError(direction=direction) 

331 

332 e = len(self) & 1 # int(isodd(len(self))) 

333 

334 c = self[-1:] # last hash char 

335 i = _GH.Neighbors[D][e].find(c) 

336 if i < 0: 

337 raise GeohashError(geohash=self) 

338 

339 p = self[:-1] # hash without last char 

340 # check for edge-cases which don't share common prefix 

341 if p and (c in _GH.Borders[D][e]): 

342 p = Geohash(p).adjacent(D) 

343 

344 n = self._name__(name) 

345 if n: 

346 n = _DOT_(n, D) 

347 # append letter for direction to parent 

348 return Geohash(p + _GH.EncodeB32[i], name=n) 

349 

350 @Property_RO 

351 def _bounds(self): 

352 '''(INTERNAL) Cache for L{bounds}. 

353 ''' 

354 return bounds(self) 

355 

356 def bounds(self, LatLon=None, **LatLon_kwds): 

357 '''Return the lower-left SW and upper-right NE bounds of this 

358 geohash cell. 

359 

360 @kwarg LatLon: Optional class to return I{bounds} (C{LatLon}) 

361 or C{None}. 

362 @kwarg LatLon_kwds: Optional, additional B{C{LatLon}} keyword 

363 arguments, ignored if C{B{LatLon} is None}. 

364 

365 @return: A L{Bounds2Tuple}C{(latlonSW, latlonNE)} of B{C{LatLon}}s 

366 or a L{Bounds4Tuple}C{(latS, lonW, latN, lonE)} if 

367 C{B{LatLon} is None}, 

368 ''' 

369 r = self._bounds 

370 return r if LatLon is None else \ 

371 _2bounds(LatLon, LatLon_kwds, *r, name=self.name) 

372 

373 def _distanceTo(self, func_, other, **kwds): 

374 '''(INTERNAL) Helper for distances, see C{.formy._distanceTo*}. 

375 ''' 

376 lls = self.latlon + _2Geohash(other).latlon 

377 return func_(*lls, **kwds) 

378 

379 def distanceTo(self, other): 

380 '''Estimate the distance between this and an other geohash 

381 based the cell sizes. 

382 

383 @arg other: The other geohash (L{Geohash}, C{LatLon} or C{str}). 

384 

385 @return: Approximate distance (C{meter}). 

386 

387 @raise TypeError: The B{C{other}} is not a L{Geohash}, 

388 C{LatLon} or C{str}. 

389 ''' 

390 other = _2Geohash(other) 

391 

392 n = min(len(self), len(other), len(_GH.Sizes)) 

393 if n: 

394 for n in range(n): 

395 if self[n] != other[n]: 

396 break 

397 return _GH.Sizes[n].radius 

398 

399 @deprecated_method 

400 def distance1To(self, other): # PYCHOK no cover 

401 '''DEPRECATED, use method L{distanceTo}.''' 

402 return self.distanceTo(other) 

403 

404 distance1 = distance1To 

405 

406 @deprecated_method 

407 def distance2To(self, other, radius=R_M, adjust=False, wrap=False): # PYCHOK no cover 

408 '''DEPRECATED, use method L{equirectangularTo}.''' 

409 return self.equirectangularTo(other, radius=radius, adjust=adjust, wrap=wrap) 

410 

411 distance2 = distance2To 

412 

413 @deprecated_method 

414 def distance3To(self, other, radius=R_M, wrap=False): # PYCHOK no cover 

415 '''DEPRECATED, use method L{haversineTo}.''' 

416 return self.haversineTo(other, radius=radius, wrap=wrap) 

417 

418 distance3 = distance3To 

419 

420 def equirectangularTo(self, other, radius=R_M, **adjust_limit_wrap): 

421 '''Approximate the distance between this and an other geohash 

422 using function L{pygeodesy.equirectangular}. 

423 

424 @arg other: The other geohash (L{Geohash}, C{LatLon} or C{str}). 

425 @kwarg radius: Mean earth radius, ellipsoid or datum (C{meter}, 

426 L{Ellipsoid}, L{Ellipsoid2}, L{Datum} or L{a_f2Tuple}) 

427 or C{None}, see function L{pygeodesy.equirectangular}. 

428 @kwarg adjust_limit_wrap: Optional keyword arguments for function 

429 L{pygeodesy.equirectangular4}, overriding defaults 

430 C{B{adjust}=False, B{limit}=None} and C{B{wrap}=False}. 

431 

432 @return: Distance (C{meter}, same units as B{C{radius}} or the ellipsoid 

433 or datum axes or C{radians I{squared}} if B{C{radius} is None} 

434 or C{0}). 

435 

436 @raise TypeError: The B{C{other}} is not a L{Geohash}, C{LatLon} or 

437 C{str} or invalid B{C{radius}}. 

438 

439 @see: U{Local, flat earth approximation 

440 <https://www.EdWilliams.org/avform.htm#flat>}, functions 

441 ''' 

442 lls = self.latlon + _2Geohash(other).latlon 

443 kwds = _xkwds(adjust_limit_wrap, adjust=False, limit=None, wrap=False) 

444 return _formy.equirectangular( *lls, radius=radius, **kwds) if radius else \ 

445 _formy.equirectangular4(*lls, **kwds).distance2 

446 

447 def euclideanTo(self, other, **radius_adjust_wrap): 

448 '''Approximate the distance between this and an other geohash using 

449 function L{pygeodesy.euclidean}. 

450 

451 @arg other: The other geohash (L{Geohash}, C{LatLon} or C{str}). 

452 @kwarg radius_adjust_wrap: Optional keyword arguments for function 

453 L{pygeodesy.euclidean}. 

454 

455 @return: Distance (C{meter}, same units as B{C{radius}} or the 

456 ellipsoid or datum axes). 

457 

458 @raise TypeError: The B{C{other}} is not a L{Geohash}, C{LatLon} 

459 or C{str} or invalid B{C{radius}}. 

460 ''' 

461 return self._distanceTo(_formy.euclidean, other, **radius_adjust_wrap) 

462 

463 def haversineTo(self, other, **radius_wrap): 

464 '''Compute the distance between this and an other geohash using 

465 the L{pygeodesy.haversine} formula. 

466 

467 @arg other: The other geohash (L{Geohash}, C{LatLon} or C{str}). 

468 @kwarg radius_wrap: Optional keyword arguments for function 

469 L{pygeodesy.haversine}. 

470 

471 @return: Distance (C{meter}, same units as B{C{radius}} or the 

472 ellipsoid or datum axes). 

473 

474 @raise TypeError: The B{C{other}} is not a L{Geohash}, C{LatLon} 

475 or C{str} or invalid B{C{radius}}. 

476 ''' 

477 return self._distanceTo(_formy.haversine, other, **radius_wrap) 

478 

479 @Property_RO 

480 def latlon(self): 

481 '''Get the lat- and longitude of (the approximate center of) 

482 this geohash as a L{LatLon2Tuple}C{(lat, lon)} in C{degrees}. 

483 ''' 

484 lat, lon = self._latlon or _2center(self.bounds()) 

485 return LatLon2Tuple(lat, lon, name=self.name) 

486 

487 @Property_RO 

488 def neighbors(self): 

489 '''Get all 8 adjacent cells as a L{Neighbors8Dict}C{(N, NE, 

490 E, SE, S, SW, W, NW)} of L{Geohash}es. 

491 ''' 

492 return Neighbors8Dict(N=self.N, NE=self.NE, E=self.E, SE=self.SE, 

493 S=self.S, SW=self.SW, W=self.W, NW=self.NW, 

494 name=self.name) 

495 

496 @Property_RO 

497 def philam(self): 

498 '''Get the lat- and longitude of (the approximate center of) 

499 this geohash as a L{PhiLam2Tuple}C{(phi, lam)} in C{radians}. 

500 ''' 

501 return PhiLam2Tuple(map2(radians, self.latlon), name=self.name) # *map2 

502 

503 @Property_RO 

504 def precision(self): 

505 '''Get this geohash's precision (C{int}). 

506 ''' 

507 return len(self) 

508 

509 @Property_RO 

510 def resolution2(self): 

511 '''Get the I{lon-} and I{latitudinal} resolution of this cell 

512 in a L{Resolutions2Tuple}C{(res1, res2)}, both in C{degrees}. 

513 ''' 

514 return resolution2(self.precision, self.precision) 

515 

516 @deprecated_property_RO 

517 def sizes(self): 

518 '''DEPRECATED on 2024.07.28, use property C{Geohash.sizes3}.''' 

519 t = self.sizes3 

520 return _GH._LatLon2Tuple(t.height, t.width, name=t.name) 

521 

522 @Property_RO 

523 def sizes3(self): 

524 '''Get the lat-, longitudinal and radial size of this cell in 

525 a L{Sizes3Tuple}C{(height, width, radius)}, all in C{meter}. 

526 ''' 

527 z = _GH.Sizes 

528 n = min(max(self.precision, 1), len(z) - 1) 

529 return Sizes3Tuple(z[n], name=self.name) 

530 

531 def toLatLon(self, LatLon=None, **LatLon_kwds): 

532 '''Return (the approximate center of) this geohash cell 

533 as an instance of the supplied C{LatLon} class. 

534 

535 @arg LatLon: Class to use (C{LatLon}) or C{None}. 

536 @kwarg LatLon_kwds: Optional, additional B{C{LatLon}} keyword 

537 arguments, ignored if C{B{LatLon} is None}. 

538 

539 @return: This geohash location (B{C{LatLon}}) or if C{B{LatLon} 

540 is None}, a L{LatLon2Tuple}C{(lat, lon)}. 

541 

542 @raise TypeError: Invalid B{C{LatLon}} or B{C{LatLon_kwds}}. 

543 ''' 

544 return self.latlon if LatLon is None else _xnamed(LatLon( 

545 *self.latlon, **LatLon_kwds), self.name) 

546 

547 def vincentysTo(self, other, **radius_wrap): 

548 '''Compute the distance between this and an other geohash using 

549 the L{pygeodesy.vincentys} formula. 

550 

551 @arg other: The other geohash (L{Geohash}, C{LatLon} or C{str}). 

552 @kwarg radius_wrap: Optional keyword arguments for function 

553 L{pygeodesy.vincentys}. 

554 

555 @return: Distance (C{meter}, same units as B{C{radius}} or the 

556 ellipsoid or datum axes). 

557 

558 @raise TypeError: The B{C{other}} is not a L{Geohash}, C{LatLon} 

559 or C{str} or invalid B{C{radius}}. 

560 ''' 

561 return self._distanceTo(_formy.vincentys, other, **radius_wrap) 

562 

563 @Property_RO 

564 def E(self): 

565 '''Get the cell East of this (L{Geohash}). 

566 ''' 

567 return self.adjacent(_E_) 

568 

569 @Property_RO 

570 def N(self): 

571 '''Get the cell North of this (L{Geohash}). 

572 ''' 

573 return self.adjacent(_N_) 

574 

575 @Property_RO 

576 def NE(self): 

577 '''Get the cell NorthEast of this (L{Geohash}). 

578 ''' 

579 return self.N.E 

580 

581 @Property_RO 

582 def NW(self): 

583 '''Get the cell NorthWest of this (L{Geohash}). 

584 ''' 

585 return self.N.W 

586 

587 @Property_RO 

588 def S(self): 

589 '''Get the cell South of this (L{Geohash}). 

590 ''' 

591 return self.adjacent(_S_) 

592 

593 @Property_RO 

594 def SE(self): 

595 '''Get the cell SouthEast of this (L{Geohash}). 

596 ''' 

597 return self.S.E 

598 

599 @Property_RO 

600 def SW(self): 

601 '''Get the cell SouthWest of this (L{Geohash}). 

602 ''' 

603 return self.S.W 

604 

605 @Property_RO 

606 def W(self): 

607 '''Get the cell West of this (L{Geohash}). 

608 ''' 

609 return self.adjacent(_W_) 

610 

611 

612class Geohashed(object): 

613 '''A cache of en- and decoded geohashes of one precision. 

614 ''' 

615 _nn = None, # 1-tuple 

616 

617 def __init__(self, precision, ndigits=None): 

618 '''New L{Geohashed} cache. 

619 

620 @arg precision: The geohash encoded length (C{int}, 1..12). 

621 @kwarg ndigits: Optional number of digits to round C{lat} 

622 and C{lon} to cache keys (C{int}, typically 

623 C{B{ndigits}=B{precision}}) or C{None} for 

624 no rounding. 

625 ''' 

626 self._p = _2Precision(precision) 

627 if ndigits is None: 

628 self._ab2 = self._ab2float 

629 else: 

630 self._ab2 = self._ab2round 

631 n = Int(ndigits=ndigits) 

632 self._nn = n, n 

633 self.clear() 

634 

635 def __len__(self): 

636 '''Return the number of I{unigue} geohashes (C{int}). 

637 ''' 

638 d = self._d 

639 d = set(d.keys()) 

640 n = len(d) 

641 for e in self._e.values(): 

642 e = set(e.values()) 

643 n += len(e - d) 

644 return n 

645 

646 def _ab2(self, *ll): # overwritten 

647 '''(INTERNAL) Make encoded keys C{a, b}. 

648 ''' 

649 return ll 

650 

651 def _ab2float(self, *ll): 

652 '''(INTERNAL) Make encoded keys C{a, b}. 

653 ''' 

654 return map(float, ll) 

655 

656 def _ab2round(self, *ll): 

657 '''(INTERNAL) Make encoded keys C{a, b}. 

658 ''' 

659 return map(round, ll, self._nn) # strict=True 

660 

661 def clear(self): 

662 '''Clear the C{en-} and C{decoded} cache. 

663 ''' 

664 self._e = {} 

665 self._d = {} 

666 

667 def decoded(self, geohash, encoded=False): 

668 '''Get and cache the C{(lat, lon)} for C{geohash}, see L{decode<pygeodesy.geohash.decode>}. 

669 

670 @kwarg encoded: If C{True}, cache the result as C{encoded}. 

671 

672 @return: The C{(lat, lon}) pair for C{geohash}. 

673 ''' 

674 try: 

675 ll = self._d[geohash] 

676 except KeyError: 

677 self._d[geohash] = ll = _GH.decode2(geohash) 

678 if encoded: 

679 a, b = self._ab2(*ll) 

680 try: 

681 _ = self._e[b][a] 

682 except KeyError: 

683 self._e.setdefault(b, {})[a] = geohash 

684 return ll 

685 

686 def encoded(self, lat, lon, decoded=False): 

687 '''Get and cache the C{geohash} for C{(lat, lon)}, see L{encode<pygeodesy.geohash.encode>}. 

688 

689 @kwarg decoded: If C{True}, cache the result as C{decoded}. 

690 

691 @return: The C{geohash} for pair C{(lat, lon}). 

692 ''' 

693 lat, lon = ll = _2fll(lat, lon) 

694 a, b = self._ab2(*ll) 

695 try: 

696 gh = self._e[b][a] 

697 except KeyError: 

698 gh = _GH.encode(lat, lon, self._p, 0) 

699 self._e.setdefault(b, {})[a] = gh 

700 if decoded and gh not in self._d: 

701 self._d[gh] = ll 

702 return gh 

703 

704 @property_RO 

705 def len2(self): 

706 '''Return 2-tuple C{(lencoded, ldecoded)} with the C{len}gths of the 

707 C{en-} and C{decoded} cache. 

708 ''' 

709 return sum(len(e) for e in self._e.values()), len(self._d) 

710 

711 @Property_RO 

712 def ndigits(self): 

713 '''Get the rounding (C{int} or C{None}). 

714 ''' 

715 return self._nn[0] 

716 

717 @Property_RO 

718 def precision(self): 

719 '''Get the C{precision} (C{int}). 

720 ''' 

721 return self._p 

722 

723 

724class GeohashError(_ValueError): 

725 '''Geohash encode, decode or other L{Geohash} issue. 

726 ''' 

727 pass 

728 

729 

730class Neighbors8Dict(_NamedDict): 

731 '''8-Dict C{(N, NE, E, SE, S, SW, W, NW)} of L{Geohash}es, 

732 providing key I{and} attribute access to the items. 

733 ''' 

734 _Keys_ = (_N_, _NE_, _E_, _SE_, _S_, _SW_, _W_, _NW_) 

735 

736 def __init__(self, **kwds): # PYCHOK no *args 

737 kwds = _xkwds(kwds, **_Neighbors8Defaults) 

738 _NamedDict.__init__(self, **kwds) # name=... 

739 

740 

741_Neighbors8Defaults = dict(zip(Neighbors8Dict._Keys_, (None,) * 

742 len(Neighbors8Dict._Keys_))) # XXX frozendict 

743 

744 

745class Resolutions2Tuple(_NamedTuple): 

746 '''2-Tuple C{(res1, res2)} with the primary I{(longitudinal)} and 

747 secondary I{(latitudinal)} resolution, both in C{degrees}. 

748 ''' 

749 _Names_ = ('res1', 'res2') 

750 _Units_ = ( Degrees_, Degrees_) 

751 

752 @property_RO 

753 def lat(self): 

754 '''Get the secondary, latitudinal resolution (C{degrees}). 

755 ''' 

756 return self[1] 

757 

758 @property_RO 

759 def lon(self): 

760 '''Get the primary, longitudinal resolution (C{degrees}). 

761 ''' 

762 return self[0] 

763 

764 

765class Sizes3Tuple(_NamedTuple): 

766 '''3-Tuple C{(height, width, radius)} with latitudinal C{height}, 

767 longitudinal C{width} and area C{radius}, all in C{meter}. 

768 ''' 

769 _Names_ = (_height_, _width_, _radius_) 

770 _Units_ = ( Meter, Meter, Meter) 

771 

772 

773def bounds(geohash, LatLon=None, **LatLon_kwds): 

774 '''Returns the lower-left SW and upper-right NE corners of a geohash. 

775 

776 @arg geohash: To be "bound" (L{Geohash}). 

777 @kwarg LatLon: Optional class to return the bounds (C{LatLon}) or C{None}. 

778 @kwarg LatLon_kwds: Optional, additional B{C{LatLon}} keyword arguments, 

779 ignored if C{B{LatLon} is None}. 

780 

781 @return: A L{Bounds2Tuple}C{(latlonSW, latlonNE)}, each a B{C{LatLon}} 

782 or if C{B{LatLon} is None}, a L{Bounds4Tuple}C{(latS, lonW, 

783 latN, lonE)}. 

784 

785 @raise TypeError: The B{C{geohash}} is not a L{Geohash}, C{LatLon} or 

786 C{str} or invalid B{C{LatLon}} or invalid B{C{LatLon_kwds}}. 

787 

788 @raise GeohashError: Invalid or C{null} B{C{geohash}}. 

789 ''' 

790 swne = _GH.swne4(geohash) 

791 return _2bounds(LatLon, LatLon_kwds, *swne, 

792 name=nameof(geohash)) # _or_nameof=geohash 

793 

794 

795def decode(geohash): 

796 '''Decode a geohash to lat-/longitude of the (approximate 

797 centre of) geohash cell to reasonable precision. 

798 

799 @arg geohash: To be decoded (L{Geohash}). 

800 

801 @return: 2-Tuple C{(latStr, lonStr)}, both C{str}. 

802 

803 @raise TypeError: The B{C{geohash}} is not a L{Geohash}, 

804 C{LatLon} or C{str}. 

805 

806 @raise GeohashError: Invalid or null B{C{geohash}}. 

807 ''' 

808 # round to near centre without excessive precision to 

809 # ⌊2-log10(Δ°)⌋ decimal places, strip trailing zeros 

810 swne = _GH.swne4(geohash) 

811 return _2latlon(*swne, fstr=_MODS.streprs.fstr) 

812 

813 

814def decode2(geohash, LatLon=None, **LatLon_kwds): 

815 '''Decode a geohash to lat-/longitude of the (approximate center 

816 of) geohash cell to reasonable precision. 

817 

818 @arg geohash: To be decoded (L{Geohash}). 

819 @kwarg LatLon: Optional class to return the location (C{LatLon}) 

820 or C{None}. 

821 @kwarg LatLon_kwds: Optional, addtional B{C{LatLon}} keyword 

822 arguments, ignored if C{B{LatLon} is None}. 

823 

824 @return: L{LatLon2Tuple}C{(lat, lon)}, both C{degrees} if 

825 C{B{LatLon} is None}, otherwise a B{C{LatLon}} instance. 

826 

827 @raise TypeError: The B{C{geohash}} is not a L{Geohash}, 

828 C{LatLon} or C{str}. 

829 

830 @raise GeohashError: Invalid or null B{C{geohash}}. 

831 ''' 

832 ll = _GH.decode2(geohash) 

833 r = LatLon2Tuple(ll) if LatLon is None else \ 

834 LatLon( *ll, **LatLon_kwds) 

835 return _xnamed(r, name__=decode2) 

836 

837 

838@deprecated_function 

839def decode_error(geohash): 

840 '''DEPRECATED on 2024.07.28, use L{geohash.decode_error2}.''' 

841 return decode_error2(geohash) 

842 

843 

844def decode_error2(geohash): 

845 '''Return the lat- and longitude decoding error for a geohash. 

846 

847 @arg geohash: To be decoded (L{Geohash}). 

848 

849 @return: A L{LatLon2Tuple}C{(lat, lon)} with the lat- and 

850 longitudinal errors in (C{degrees}). 

851 

852 @raise TypeError: The B{C{geohash}} is not a L{Geohash}, 

853 C{LatLon} or C{str}. 

854 

855 @raise GeohashError: Invalid or null B{C{geohash}}. 

856 ''' 

857 s, w, n, e = _GH.swne4(geohash) 

858 return LatLon2Tuple((n - s) * _0_5, # lat error 

859 (e - w) * _0_5) # lon error 

860 

861 

862def distance_(geohash1, geohash2): 

863 '''Estimate the distance between two geohash (from the cell sizes). 

864 

865 @arg geohash1: First geohash (L{Geohash}, C{LatLon} or C{str}). 

866 @arg geohash2: Second geohash (L{Geohash}, C{LatLon} or C{str}). 

867 

868 @return: Approximate distance (C{meter}). 

869 

870 @raise TypeError: If B{C{geohash1}} or B{C{geohash2}} is not a 

871 L{Geohash}, C{LatLon} or C{str}. 

872 ''' 

873 return _2Geohash(geohash1).distanceTo(geohash2) 

874 

875 

876@deprecated_function 

877def distance1(geohash1, geohash2): 

878 '''DEPRECATED, use L{geohash.distance_}.''' 

879 return distance_(geohash1, geohash2) 

880 

881 

882@deprecated_function 

883def distance2(geohash1, geohash2): 

884 '''DEPRECATED, use L{geohash.equirectangular4}.''' 

885 return equirectangular4(geohash1, geohash2) 

886 

887 

888@deprecated_function 

889def distance3(geohash1, geohash2): 

890 '''DEPRECATED, use L{geohash.haversine_}.''' 

891 return haversine_(geohash1, geohash2) 

892 

893 

894def encode(lat, lon, precision=None, eps=EPS): 

895 '''Encode a lat-/longitude as a C{geohash}, either to the specified 

896 precision or if not provided, to an inferred precision. 

897 

898 @arg lat: Latitude (C{degrees90}). 

899 @arg lon: Longitude (C{degrees180}). 

900 @kwarg precision: The desired geohash length (C{int} 1..12) or 

901 C{None} or C{0} for inferred. 

902 @kwarg eps: Optional inference tolerance (C{degrees}), ignored 

903 if B{C{precision}} is not C{None} or C{0}. 

904 

905 @return: The C{geohash} (C{str}). 

906 

907 @raise GeohashError: Invalid B{C{lat}}, B{C{lon}} or B{C{precision}}. 

908 ''' 

909 gh, _ = _GH.encode2(lat, lon, precision, eps) 

910 return gh 

911 

912 

913def equirectangular4(geohash1, geohash2, radius=R_M): 

914 '''Approximate the distance between two geohashes using the 

915 L{pygeodesy.equirectangular} formula. 

916 

917 @arg geohash1: First geohash (L{Geohash}, C{LatLon} or C{str}). 

918 @arg geohash2: Second geohash (L{Geohash}, C{LatLon} or C{str}). 

919 @kwarg radius: Mean earth radius (C{meter}) or C{None}, see method 

920 L{Geohash.equirectangularTo}. 

921 

922 @return: Approximate distance (C{meter}, same units as B{C{radius}}), 

923 see method L{Geohash.equirectangularTo}. 

924 

925 @raise TypeError: If B{C{geohash1}} or B{C{geohash2}} is not a 

926 L{Geohash}, C{LatLon} or C{str}. 

927 ''' 

928 return _2Geohash(geohash1).equirectangularTo(geohash2, radius=radius) 

929 

930 

931def euclidean_(geohash1, geohash2, **radius_adjust_wrap): 

932 '''Approximate the distance between two geohashes using the 

933 L{pygeodesy.euclidean} formula. 

934 

935 @arg geohash1: First geohash (L{Geohash}, C{LatLon} or C{str}). 

936 @arg geohash2: Second geohash (L{Geohash}, C{LatLon} or C{str}). 

937 @kwarg radius_adjust_wrap: Optional keyword arguments for function 

938 L{pygeodesy.euclidean}. 

939 

940 @return: Approximate distance (C{meter}, same units as B{C{radius}}). 

941 

942 @raise TypeError: If B{C{geohash1}} or B{C{geohash2}} is not a 

943 L{Geohash}, C{LatLon} or C{str}. 

944 ''' 

945 return _2Geohash(geohash1).euclideanTo(geohash2, **radius_adjust_wrap) 

946 

947 

948def haversine_(geohash1, geohash2, **radius_wrap): 

949 '''Compute the great-circle distance between two geohashes 

950 using the L{pygeodesy.haversine} formula. 

951 

952 @arg geohash1: First geohash (L{Geohash}, C{LatLon} or C{str}). 

953 @arg geohash2: Second geohash (L{Geohash}, C{LatLon} or C{str}). 

954 @kwarg radius_wrap: Optional keyword arguments for function 

955 L{pygeodesy.haversine}. 

956 

957 @return: Great-circle distance (C{meter}, same units as 

958 B{C{radius}}). 

959 

960 @raise TypeError: If B{C{geohash1}} or B{C{geohash2}} is 

961 not a L{Geohash}, C{LatLon} or C{str}. 

962 ''' 

963 return _2Geohash(geohash1).haversineTo(geohash2, **radius_wrap) 

964 

965 

966def neighbors(geohash): 

967 '''Return the L{Geohash}es for all 8 adjacent cells. 

968 

969 @arg geohash: Cell for which neighbors are requested 

970 (L{Geohash} or C{str}). 

971 

972 @return: A L{Neighbors8Dict}C{(N, NE, E, SE, S, SW, W, NW)} 

973 of L{Geohash}es. 

974 

975 @raise TypeError: The B{C{geohash}} is not a L{Geohash}, 

976 C{LatLon} or C{str}. 

977 ''' 

978 return _2Geohash(geohash).neighbors 

979 

980 

981def precision(res1, res2=None): 

982 '''Determine the L{Geohash} precisions to meet a or both given 

983 (geographic) resolutions. 

984 

985 @arg res1: The required primary I{(longitudinal)} resolution 

986 (C{degrees}). 

987 @kwarg res2: Optional, required secondary I{(latitudinal)} 

988 resolution (C{degrees}). 

989 

990 @return: The L{Geohash} precision or length (C{int}, 1..12). 

991 

992 @raise GeohashError: Invalid B{C{res1}} or B{C{res2}}. 

993 

994 @see: C++ class U{Geohash 

995 <https://GeographicLib.SourceForge.io/C++/doc/classGeographicLib_1_1Geohash.html>}. 

996 ''' 

997 r = Degrees_(res1=res1, low=_0_0, Error=GeohashError) 

998 N = res2 is None 

999 t = r, (r if N else Degrees_(res2=res2, low=_0_0, Error=GeohashError)) 

1000 for p in range(1, _MaxPrec): 

1001 if resolution2(p, (None if N else p)) <= t: 

1002 return p 

1003 return _MaxPrec 

1004 

1005 

1006def resolution2(prec1, prec2=None): 

1007 '''Determine the (geographic) resolutions of given L{Geohash} 

1008 precisions. 

1009 

1010 @arg prec1: The given primary I{(longitudinal)} precision 

1011 (C{int} 1..12). 

1012 @kwarg prec2: Optional, secondary I{(latitudinal)} precision 

1013 (C{int} 1..12). 

1014 

1015 @return: L{Resolutions2Tuple}C{(res1, res2)} with the 

1016 (geographic) resolutions in C{degrees}, where 

1017 C{res2 B{is} res1} if no B{C{prec2}} is given. 

1018 

1019 @raise GeohashError: Invalid B{C{prec1}} or B{C{prec2}}. 

1020 

1021 @see: I{Karney}'s C++ class U{Geohash 

1022 <https://GeographicLib.SourceForge.io/C++/doc/classGeographicLib_1_1Geohash.html>}. 

1023 ''' 

1024 lon = _2res(_360_0, prec1=prec1) 

1025 lat = lon if prec2 is None else \ 

1026 _2res(_180_0, prec2=prec2) 

1027 return Resolutions2Tuple(lon, lat) 

1028 

1029 

1030@deprecated_function 

1031def sizes(geohash): 

1032 '''DEPRECATED on 2024.07.28, use function L{pygeodesy.geohash.sizes3}.''' 

1033 t = sizes3(geohash) 

1034 return _GH._LatLon2Tuple(t.height, t.width, name=t.name) 

1035 

1036 

1037def sizes3(geohash): 

1038 '''Return the lat-, longitudinal and radial size of this L{Geohash} cell. 

1039 

1040 @arg geohash: Cell for which size are required (L{Geohash} or C{str}). 

1041 

1042 @return: A L{Sizes3Tuple}C{(height, width, radius)}, all C{meter}. 

1043 

1044 @raise TypeError: The B{C{geohash}} is not a L{Geohash}, C{LatLon} or C{str}. 

1045 ''' 

1046 return _2Geohash(geohash).sizes3 

1047 

1048 

1049def vincentys_(geohash1, geohash2, **radius_wrap): 

1050 '''Compute the distance between two geohashes using the 

1051 L{pygeodesy.vincentys} formula. 

1052 

1053 @arg geohash1: First geohash (L{Geohash}, C{LatLon} or C{str}). 

1054 @arg geohash2: Second geohash (L{Geohash}, C{LatLon} or C{str}). 

1055 @kwarg radius_wrap: Optional keyword arguments for function 

1056 L{pygeodesy.vincentys}. 

1057 

1058 @return: Distance (C{meter}, same units as B{C{radius}}). 

1059 

1060 @raise TypeError: If B{C{geohash1}} or B{C{geohash2}} is not a 

1061 L{Geohash}, C{LatLon} or C{str}. 

1062 ''' 

1063 return _2Geohash(geohash1).vincentysTo(geohash2, **radius_wrap) 

1064 

1065 

1066__all__ += _ALL_DOCS(bounds, # functions 

1067 decode, decode2, decode_error2, distance_, 

1068 encode, equirectangular4, euclidean_, haversine_, 

1069 neighbors, precision, resolution2, sizes3, vincentys_, 

1070 decode_error, sizes) # DEPRECATED 

1071 

1072if __name__ == _DMAIN_: 

1073 

1074 from pygeodesy.internals import printf, _versions 

1075 from timeit import timeit 

1076 

1077 for f, p in (('encode', _MaxPrec), ('infer', None)): 

1078 

1079 def _t(prec=p): 

1080 i = 0 

1081 for lat in range(-90, 90, 3): 

1082 for lon in range(-180, 180, 7): 

1083 _ = encode(lat, lon, prec) 

1084 i += 1 

1085 return i 

1086 

1087 i = _t() # prime 

1088 n = 10 

1089 t = timeit(_t, number=n) / (i * n) 

1090 printf('%s %.3f usec, %s', f, t * 1e6, _versions()) 

1091 

1092# % python3.12 -m pygeodesy.geohash 

1093# encode 10.145 usec, pygeodesy 24.8.4 Python 3.12.4 64bit arm64 macOS 14.5 

1094# infer 14.780 usec, pygeodesy 24.8.4 Python 3.12.4 64bit arm64 macOS 14.5 

1095# or about 6.56 and 74.12 times faster than pygeodesy 24.7.24 and older: 

1096# encode 66.524 usec, pygeodesy 24.7.24 Python 3.12.4 64bit arm64 macOS 14.5 

1097# infer 1095.386 usec, pygeodesy 24.7.24 Python 3.12.4 64bit arm64 macOS 14.5 

1098 

1099# **) MIT License 

1100# 

1101# Copyright (C) 2016-2025 -- mrJean1 at Gmail -- All Rights Reserved. 

1102# 

1103# Permission is hereby granted, free of charge, to any person obtaining a 

1104# copy of this software and associated documentation files (the "Software"), 

1105# to deal in the Software without restriction, including without limitation 

1106# the rights to use, copy, modify, merge, publish, distribute, sublicense, 

1107# and/or sell copies of the Software, and to permit persons to whom the 

1108# Software is furnished to do so, subject to the following conditions: 

1109# 

1110# The above copyright notice and this permission notice shall be included 

1111# in all copies or substantial portions of the Software. 

1112# 

1113# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 

1114# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 

1115# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 

1116# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR 

1117# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 

1118# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 

1119# OTHER DEALINGS IN THE SOFTWARE.