Coverage for pyrdnap / rdnap2018.py: 93%

242 statements  

« prev     ^ index     » next       coverage.py v7.14.0, created at 2026-06-06 16:53 -0400

1 

2# -*- coding: utf-8 -*- 

3 

4u'''Main classes L{RDNAP2018v1} and L{RDNAP2018v2} follow C{variant 1} respectively C{variant 2} of 

5the U{RDNAPTRANS(tm)2018_v220627<https://formulieren.kadaster.nl/aanvragen_rdnaptrans>} specification. 

6Each provide a C{forward} method to convert geodetic lat-/longitudes and heights to C{RD} coodinates 

7and C{NAP} heights and a C{reverse} method for converting the other way. 

8 

9The L{RDNAP2018v1.forward} and C{.reverse} results are within the C{RDNAPTRANS(tm)2018_v220627} 

10self-validation requirements of C{0.000000010 degrees} respectively C{0.0010 meter} for points inside 

11the C{RD} region, see B{C{Note below}}. Class L{RDNAP2018v2} does not. 

12 

13@note: L{RDNAP2018v1}, C{PyRDNAP} and C{pyrdnap} have B{not been formally validated} and are 

14 B{not certified} to carry the trademark C{RDNAPTRANS(tm)}. 

15''' 

16# make sure int/int division yields float quotient, see .basics 

17from __future__ import division as _; del _ # noqa: E702 ; 

18 

19from pyrdnap.rd0 import _RD, _RD0 as A0, RDNAP7Tuple 

20from pyrdnap.v_grids import RDNAPError, _V_grid, _v_gridz_import 

21from pyrdnap.__pygeodesy import (_0_0, _0_5, _1_0, _2_0, 

22 _isNAN, _isNAN0, _earth_datum, 

23 _ALL_DOCS, _ALL_OTHER, _FOR_DOCS, 

24 _NamedBase, notOverloaded) 

25from pygeodesy import (map1, EPS0, EPS1, NAN, PI_2, PI, PI2, # "consterns" 

26 Datum, Ellipsoid, LatLonDatum3Tuple, # datums, ellipsoids 

27 property_RO, property_ROnce, # props 

28 Lamd, Lat, Lon, Phid, # units 

29 sincos2, sincos2d) # utily 

30 

31from math import asin, atan, copysign, degrees, exp, \ 

32 fabs, floor, hypot, radians, sin, sqrt 

33 

34__all__ = () 

35__version__ = '26.06.06' 

36 

37_TOL_D = 1e-9 # degrees 2.3.3f+ 

38_TOL_M = 1e-6 # meter 

39_TOL_R = radians(_TOL_D) # 2e-11 

40_TRIPS = 16 # 5..6 sufficient 

41 

42 

43class _RDNAPbase(_NamedBase): # in .rd0._RD.regionB 

44 '''(INTERNAL) L{RDNAP2018v1}C{/-v2} base class. 

45 ''' 

46 _datum = None # forward, v1 reverse Datum, lazily (GRS80) 

47 _EETRS = None # forward, v1 reverse Ellipsoid, lazily 

48 _raiser = False 

49 

50 def __init__(self, a_ellipsoid=None, f=None, raiser=False, **name): 

51 '''New C{RDNAP2018v1} or C{-v2} instance. 

52 

53 @kwarg a_ellipsoid: An ellipsoid (L{Ellipsoid}) or the ellipsoid's equatorial 

54 radius (C{scalar}, conventionally in C{meter}), see B{C{f}} 

55 or a datum (L{Datum}). Default C{Datums.GRS80} for ETRS89. 

56 @kwarg f: The flattening of the ellipsoid (C{scalar}) if B{C{a_ellipsoid}} is 

57 specified as C{scalar}, ignored otherwise. 

58 @kwarg raiser: If C{True} raise an L{RDNAPError} for lat-/longitudes outside 

59 the C{RD} region (C{bool}). 

60 @kwarg name: Optional name (C{str}). 

61 

62 @raise RDNAPError: Ellipsoid (or datum) is not oblate (i.e. is spherical or 

63 prolate) or the datum's C{transform} is not C{unity}. 

64 ''' 

65 if a_ellipsoid is f is None: 

66 self._datum = A0.D80 # GRS80 (ETRS89) 

67 else: 

68 _earth_datum(self, a_ellipsoid, f, **name) # sets self._datum 

69 self._EETRS = E = self._datum.ellipsoid 

70 if not E.isOblate: 

71 raise RDNAPError('not oblate: %r' % (E,)) 

72 if raiser: # PYCHOK no cover 

73 T = self._datum.transform 

74 if not T.isunity: 

75 raise RDNAPError('not unity: %r' % (T,)) 

76 self._raiser = True 

77 if name: 

78 self.name = name 

79 

80 def forward(self, lat, lon, height=0, raiser=None, name='forward'): 

81 '''Convert GRS80 (ETRS98) geodetic C{(B{lat}, B{lon})} and B{C{height}} 

82 to local C{(RDx, RDy)} coordinates and C{NAPh} quasi-geoid-height. 

83 

84 @arg lat: Latitude (C{degrees} geodetic). 

85 @arg lon: Longitude (C{degrees} geodetic). 

86 @kwarg height: Height, optional (C{meter} above geoid) or C{NAN} 

87 to ignore C{NAPh} interpolation. 

88 @kwarg raiser: If C{True} raise an L{RDNAPError} if B{C{lat}} or 

89 B{C{lon}} is outside the C{RD} region (C{bool}), 

90 if C{False} don't, overriding property C{raiser}. 

91 @kwarg name: Optional name (C{str}). 

92 

93 @return: An L{RDNAP7Tuple}C{(RDx, RDy, NAPh, lat, lon, height, datum)} 

94 with local C{RDx}, C{RDy} coordinates and C{NAPh} height. 

95 ''' 

96 lat, lon = Lat(lat), Lon(lon) 

97 lat0, lon0 = \ 

98 lat_, lon_ = self._forwardXform2(raiser, lat, lon) 

99 for _ in range(_TRIPS): # 2.3.3a-f, 1..2 

100 latc, lonc = self._rdlatlon2(lat_, lon_, lat0, lon0) 

101 if fabs(latc - lat_) < _TOL_D and \ 

102 fabs(lonc - lon_) < _TOL_D: 

103 break 

104 lat_, lon_ = latc, lonc 

105 

106 phiClamC = _ellipsoidal2spherical(latc, lonc) 

107 RDx, RDy = _spherical2oblique(*phiClamC) 

108 NAPh = NAN if _isNAN(height) else (height - # NOT lat0, lon0 

109 self._rdNAPh_v(lat, lon, latc, lonc)) # 2.5.2 

110 return RDNAP7Tuple(RDx, RDy, NAPh, 

111 lat, lon, height, self.forwardDatum, name=name) 

112 

113 def forward3(self, lat, lon, name='forward3'): 

114 '''Datum transform C{(B{lat}, B{lon})} from GRS80 (ETRS98) to Bessel1841 (RD-Bessel). 

115 

116 @return: A L{LatLonDatum3Tuple}C{(lat, lon, datum)}. 

117 ''' 

118 x, y, z = _geodetic2cartesian(lat, lon, A0.H0_ETRS, self._EETRS) 

119 x, y, z = _RD._xETRS2RD.transform(x, y, z) 

120 lat, lon = _cartesian2geodetic(x, y, z, A0.E0) 

121 return LatLonDatum3Tuple(lat, lon, A0.D0, name=name) 

122 

123 @property_RO 

124 def forwardDatum(self): 

125 '''Get the C{forward} datum (L{Datum}, default GRS80). 

126 ''' 

127 return self._datum 

128 

129 def _inside2(self, raiser, lat, lon): 

130 # default and variant 2: no datum Xform 

131 if (raiser or (raiser is None and self._raiser)) and \ 

132 not _RD.isinside(lat, lon): 

133 raise self._outsidError(lat, lon) 

134 return lat, lon 

135 

136 _forwardXform2 = _inside2 # no datum Xform 

137 

138 def isinside(self, lat, lon, eps=0, B=False): 

139 '''Is geodetic C{(B{lat}, B{lon})} inside the C{RD} region (C{bool})? 

140 

141 @kwarg eps: Over-/undersize the C{RD} region (C{degrees}). 

142 @kwarg B: Use C{B{B}=True} for the C{RD-Bessel} regionB in case 

143 C{(B{lat}, B{lon})} are Bessel1841 and not GRS80. 

144 ''' 

145 return _RD.isinside(Lat(lat), Lon(lon), eps, B) 

146 

147 def _outsidError(self, *lat_lon): 

148 # format an RDNAPError for C{lat_lon} outside C{RD} region 

149 return RDNAPError('%r outside %s' % (lat_lon, self.region)) 

150 

151 @property_RO 

152 def _rdgrid(self): # PYCHOK no cover 

153 raise notOverloaded(self) 

154 

155 def _rdlatlon2(self, lat, lon, lat0=None, lon0=None): # 2.3.2 

156 # return the RD-corrected C{(lat, lon)} 

157 if _RD.isinside(lat, lon): 

158 c_f_N_f6 = _RD._c_f_N_f6(lat, lon) 

159 lat_corr = _bilinear(self._rdgrid._lat_corr, *c_f_N_f6) 

160 lon_corr = _bilinear(self._rdgrid._lon_corr, *c_f_N_f6) 

161 

162 if lat0 is lon0 is None: # reverse 

163 lat += lat_corr 

164 lon += lon_corr 

165 else: # forward 

166 lat = lat0 - lat_corr 

167 lon = lon0 - lon_corr 

168 return lat, lon # NAN, NAN? 

169 

170 def rdNAPh(self, lat, lon, raiser=False): # 2.5.1 and 3.5 

171 '''Interpolate the C{NAPh} quasi-geoid-height I{within} the C{RD} region. 

172 

173 @arg lat: Latitude (C{degrees} geodetic). 

174 @arg lon: Longitude (C{degrees} geodetic). 

175 @kwarg raiser: If C{True} raise an L{RDNAPError} if B{C{lat}} or 

176 B{C{lon}} is outside the C{RD} region (C{bool}), 

177 otherwise don't and return C{NAN}. 

178 

179 @return: C{NAPh} (C{meter}) or C{NAN} if C{B{raiser} is False} and 

180 B{C{lat}} or B{C{lon}} is outside the C{RD} region. 

181 ''' 

182 return self._rdNAPh(Lat(lat), Lon(lon), raiser) 

183 

184 def _rdNAPh(self, lat, lon, raiser): 

185 # return C{NAPh} at C{(lat, lon)} or C{NAN} if outside 

186 if _RD.isinside(lat, lon): # eps=0 

187 c_f_N_f6 = _RD._c_f_N_f6(lat, lon) 

188 return _bilinear(self._rdgrid._NAP_h, *c_f_N_f6) 

189 elif raiser: 

190 raise self._outsidError(lat, lon) 

191 return NAN # c0 2.5.1e+ 

192 

193 def _rdNAPh_v(self, lat1, lon1, lat2, lon2): 

194 # get C{NAPh} at geodetic C{lat1, lon1} for variant 1 or at the 

195 # RD-corrected or inverse-projected C{lat2, lon2} for variant 2 

196 if self.variant == 2: 

197 lat1, lon1 = lat2, lon2 

198 return self._rdNAPh(lat1, lon1, False) 

199 

200 @property_ROnce 

201 def region(self): 

202 '''Get the C{RD} region as L{Bounds4Tuple}C{(latS, lonW, latN, lonE)}, all C{GRS80 (ETRS89) degrees}. 

203 ''' 

204 return _RD.region 

205 

206 @property_ROnce 

207 def regionB(self): # in .rd0._RD.regionB 

208 '''Get the C{RD} region as L{Bounds4Tuple}C{(latS, lonW, latN, lonE)}, all C{Bessel1841 (RD-Bessel) degrees}. 

209 ''' 

210 S, W, N, E = r = self.region # Bounds4Tuple 

211 _R = _RDNAPbase 

212 _f = _R().forward3 

213 nB = r.name.replace(_R.region.name, _R.regionB.name) 

214 s, w, _ = _f(S, W) 

215 n, e, _ = _f(N, E) 

216 return r.classof(s, w, n, e, name=nB) # r.dup(latS=S, ...) 

217 

218 def reverse3(self, lat, lon, name='reverse3'): 

219 '''Datum transform C{(B{lat}, B{lon})} from Bessel1841 (RD-Bessel) to GRS80 (ETRS98). 

220 

221 @return: A L{LatLon3Tuple}C{(lat, lon, datum)}. 

222 ''' 

223 x, y, z = _geodetic2cartesian(lat, lon, A0.H0, A0.E0) 

224 x, y, z = _RD._xRD2ETRS.transform(x, y, z) 

225 lat, lon = _cartesian2geodetic(x, y, z, self._EETRS) 

226 return LatLonDatum3Tuple(lat, lon, self.forwardDatum, name=name) 

227 

228 def _reverse(self, RDx, RDy, NAPh, toRD, raiser=None, name='reverse'): 

229 '''(INTERNAL) Convert local C{(B{RDx}, B{RDy})} coordinates and 

230 B{C{NAPh}} quasi-geoid-height to GRS80 (ETRS89) or Bessel1841 

231 (RD-Bessel) geodetic C{lat}, C{lon} and C{height}. 

232 ''' 

233 phiClamC = _oblique2spherical(RDx, RDy) 

234 latlon = _spherical2ellipsoidal(*phiClamC) 

235 

236 latc, lonc = self._rdlatlon2(*latlon) 

237 lat, lon, _ = self._reverseXform3(raiser, latc, lonc) 

238 h = NAN if _isNAN(NAPh) else (NAPh + 

239 self._rdNAPh_v(lat, lon, *latlon)) 

240 

241 if toRD: # RD_Bessel 

242 lat, lon, d = latc, lonc, A0.D0 

243 else: # GRS80 (ETRS89) 

244 d = self._EETRS 

245 return RDNAP7Tuple(RDx, RDy, NAPh, 

246 lat, lon, h, d, name=name) 

247 

248 @property_RO 

249 def reverseDatum(self): 

250 '''Get the I{default} C{reverse} datum (L{Datum}), GRS80 or Bessel1841. 

251 ''' 

252 return {1: self._datum, # A0.D80 

253 2: A0.D0}.get(self.variant) 

254 

255 def _reverseXform3(self, *raiser_lat_lon): 

256 # datum transform C{(lat, lon)} from RD-Bessel to GRS80 (ETRS89) 

257 # and raise an C{RDNAPError} if outside the C{RD} region 

258 lat, lon = self._inside2(*raiser_lat_lon) 

259 return self.reverse3(lat, lon) 

260 

261 def similarity(self, inverse=None): # PYCHOK no cover 

262 raise notOverloaded(self, inverse=inverse) # PYCHOK None 

263 

264 def toStr(self, prec=9, **unused): # PYCHOK signature 

265 '''Return this C{RDNAP20181v1} or C{-v2} instance as a string. 

266 

267 @kwarg prec: Precision, number of decimal digits (0..9). 

268 

269 @return: This C{RDNAP2018v1} or C{-v2} (C{str}). 

270 ''' 

271 return self.attrs('name', 'variant', 'forwardDatum', prec=prec) # _ellipsoid_, _name__ 

272 

273 @property_RO 

274 def variant(self): # PYCHOK no cover 

275 raise notOverloaded(self) 

276 

277 

278class RDNAP2018v1(_RDNAPbase): 

279 '''Transformer implementing C{variant 1} of U{RD NAP 2018 v220627 

280 <https://formulieren.kadaster.nl/aanvragen_rdnaptrans>}. 

281 

282 @note: Method L{RDNAP2018v1.reverse} returns B{GRS80 (ETRS89)} 

283 geodetic lat- and longitudes. 

284 

285 @note: L{RDNAP2018v1} has B{not been formally validated} and is 

286 B{not certified} to carry the trademark C{RDNAPTRANS(tm)}. 

287 ''' 

288 if _FOR_DOCS: 

289 __init__ = _RDNAPbase.__init__ 

290 forward = _RDNAPbase.forward 

291 forward3 = _RDNAPbase.forward3 

292 reverse3 = _RDNAPbase.reverse3 

293 

294 def _forwardXform2(self, raiser, lat, lon): 

295 # datum transform C{(lat, lon)} from GRS80 (ETRS89) to RD-Bessel 

296 # and raise an C{RDNAPError} if outside the C{RD} region 

297 lat, lon, _ = self.forward3(lat, lon) 

298 return self._inside2(raiser, lat, lon) 

299 

300 @property_ROnce 

301 def _rdgrid(self): 

302 try: 

303 from pyrdnap import v1grid 

304 except (AttributeError, ImportError, RDNAPError): 

305 v1grid = _v_gridz_import(self.variant) 

306 return v1grid 

307 

308 def reverse(self, RDx, RDy, NAPh=0, toRD=False, **raiser_name): 

309 '''Convert a local C{(B{RDx}, B{RDy})} point and B{C{NAPh}} height to 

310 B{GRS80 (ETRS89)} geodetic C{(lat, lon, height)}, by default. 

311 

312 @arg RDx: Local C{RD} X (C{meter}, conventionally). 

313 @arg RDy: Local C{RD} Y (C{meter}, conventionally). 

314 @kwarg NAPh: C{NAP} quasi-geoid-height (C{meter}, conventionally) 

315 or C{NAN} to ignore C{NAPh} interpolation. 

316 @kwarg toRD: Use C{B{toRD}=True} to return Bessel1841 (RD-Bessel) 

317 lat- and longitudes instead of GRS80 (ETRS89) (C{bool}). 

318 @kwarg raiser_name: Like the C{forward} method, C{B{raiser}=None} 

319 (C{bool}) and optional C{B{name}='reverse'} (C{str}). 

320 

321 @return: An L{RDNAP7Tuple}C{(RDx, RDy, NAPh, lat, lon, height, datum)} 

322 with geodetic C{lat} and C{lon}, C{height} and C{datum} 

323 B{GRS80 (ETRS89)} or C{Bessel1841 (RD-Bessel)}. 

324 ''' 

325 return self._reverse(RDx, RDy, NAPh, toRD, **raiser_name) 

326 

327 def similarity(self, inverse=False): 

328 '''Get the similarity transform (C{Similarity}). 

329 

330 @kwarg inverse: Use C{True} for the C{reverse} or C{False} 

331 for the C{forward} transform (C{bool}). 

332 ''' 

333 return _RD._xRD2ETRS if inverse else _RD._xETRS2RD 

334 

335 @property_ROnce 

336 def variant(self): 

337 '''Get this C{RDNAP2018}'s variant (C{int}). 

338 ''' 

339 return 1 

340 

341 

342class RDNAP2018v2(_RDNAPbase): 

343 '''Transformer implementing C{variant 2} of U{RD NAP 2018 v220627 

344 <https://formulieren.kadaster.nl/aanvragen_rdnaptrans>}. 

345 

346 @note: Method L{RDNAP2018v2.reverse} returns by default B{Bessel1841 

347 (RD-Bessel)} and optionally GRS80 (ETRS89) geodetic lat- and 

348 longitudes. 

349 

350 @note: L{RDNAP2018v2} has B{not been formally validated} and is 

351 B{not certified} to carry the trademark C{RDNAPTRANS(tm)}. 

352 ''' 

353 if _FOR_DOCS: 

354 __init__ = _RDNAPbase.__init__ 

355 forward = _RDNAPbase.forward 

356 forward3 = _RDNAPbase.forward3 

357 reverse3 = _RDNAPbase.reverse3 

358 

359 @property_ROnce 

360 def _rdgrid(self): 

361 try: 

362 from pyrdnap import v2grid 

363 except (AttributeError, ImportError, RDNAPError): 

364 v2grid = _v_gridz_import(self.variant) 

365 return v2grid 

366 

367 def reverse(self, RDx, RDy, NAPh=0, toRD=True, **raiser_name): 

368 '''Convert a local C{(B{RDx}, B{RDy})} point and B{C{NAPh}} height to 

369 B{Bessel1841 (RD-Bessel)} geodetic C{(lat, lon, height)}, by default. 

370 

371 @arg RDx: Local C{RD} X (C{meter}, conventionally). 

372 @arg RDy: Local C{RD} Y (C{meter}, conventionally). 

373 @kwarg NAPh: C{NAP} quasi-geoid-height (C{meter}, conventionally) 

374 or C{NAN} to ignore C{NAPh} interpolation. 

375 @kwarg toRD: Use C{B{toRD}=False} to return GRS80 (ETRS89) lat- and 

376 longitudes instead of Bessel1841 (RD-Bessel) (C{bool}). 

377 @kwarg raiser_name: Like the C{forward} method, C{B{raiser}=None} 

378 (C{bool}) and optional C{B{name}='reverse'} (C{str}). 

379 

380 @return: An L{RDNAP7Tuple}C{(RDx, RDy, NAPh, lat, lon, height, datum)} 

381 with geodetic C{lat} and C{lon}, C{height} and C{datum} 

382 B{Bessel1841 (RD-Bessel)} or C{GRS80 (ETRS89)}. 

383 ''' 

384 return self._reverse(RDx, RDy, NAPh, toRD, **raiser_name) 

385 

386 def similarity(self, *unused): # PYCHOK signature 

387 '''Get the similarity transform, always C{None}. 

388 ''' 

389 return None 

390 

391 @property_ROnce 

392 def variant(self): 

393 '''Get this C{RDNAP2018}'s variant (C{int}). 

394 ''' 

395 return 2 

396 

397 

398def _atan3(y, x, x0): # 2.2.3e and 3.1.1i 

399 # equiv to math.atan2 iff x0 is y 

400 if x > 0: 

401 r = atan(y / x) 

402 elif x < 0: 

403 r = atan(y / x) + copysign(PI, x0) 

404 else: 

405 r = copysign(PI_2, x0) if x0 else _0_0 

406 return r 

407 

408 

409def _atan_exp(w): # 2.4.1c 

410 return atan(exp(w)) * _2_0 - PI_2 

411 

412 

413def _bilinear(v_grid, c_latI, f_latI, latN_f, # 2.3.1f and g 

414 c_lonI, f_lonI, lonN_f): 

415 # interpolate a lat_corr_, lon_corr_ or NAP_... 

416 assert isinstance(v_grid, _V_grid), v_grid 

417 ne = v_grid(c_latI, c_lonI) 

418 nw = v_grid(c_latI, f_lonI) 

419 se = v_grid(f_latI, c_lonI) 

420 sw = v_grid(f_latI, f_lonI) 

421 lonN_f1 = _1_0 - lonN_f # == 1 - (lonN - f_lonN) 

422 return (ne * lonN_f + nw * lonN_f1) * latN_f + \ 

423 (se * lonN_f + sw * lonN_f1) * (_1_0 - latN_f) 

424 

425 

426def _cartesian2geodetic(x, y, z, E): # 2.2.3 == EcefUPC.reverse? 

427 # convert cartesian C{(x, y, z)} to C{E}-geodetic C{(lat, lon)} 

428 r = hypot(x, y) 

429 if r > _TOL_M: 

430 a = E.a * E.e2 

431 phi_ = atan(z / r) # atan2(z, r) 

432 for _ in range(_TRIPS): # 4..6 

433 s = sin(phi_) 

434 s *= a / sqrt(_1_0 - s**2 * E.e2) 

435 phi = atan((z + s) / r) # atan2(z + s, r) 

436 if fabs(phi - phi_) < _TOL_R: 

437 break 

438 phi_ = phi 

439 else: 

440 phi = copysign(PI_2, z) 

441 lam = _atan3(y, x, y) 

442 return map1(degrees, phi, lam) # lat, lon 

443 

444 

445def _ellipsoidal2spherical(lat, lon): # 2.4.1 

446 # convert geodetic C{(lat, lon)} to spherical C{(𝛷, 𝛬)} 

447 phiC = phi = Phid(lat) 

448 if PI_2 > phi > -PI_2: # 2.4.1c 

449 q = A0.log_tan(phi) - A0.log_e_2(phi) 

450 w = A0.N0 * q + A0.M0 # 2.4.1b 

451 phiC = _atan_exp(w) 

452 lamC = (Lamd(lon) - A0.LAM0) * A0.N0 + A0.LAM0C # 2.4.1d 

453 return phiC, lamC # -Capital 𝛷, 𝛬 

454 

455 

456def _eq0(r, r0=_0_0): 

457 return fabs(r - r0) < _TOL_R 

458 

459 

460# def _eq0d(d, d0=_0_0): 

461# return fabs(d - d0) < _TOL_D 

462 

463 

464def _geodetic2cartesian(lat, lon, h, E): # 2.2.1 

465 # convert C{E}-geodetic C{(lat, lon)} to cartesian C{(x, y, z)} 

466 y, x = sincos2d(lon) 

467 z, c = sincos2d(lat) 

468 n = E.a / sqrt(_1_0 - z**2 * E.e2) 

469 H = _isNAN0(h) 

470 c *= n + H 

471 x *= c 

472 y *= c 

473 z *= n * (_1_0 - E.e2) + H 

474 return x, y, z 

475 

476 

477def _ne0(r, r0=_0_0): 

478 return fabs(r - r0) > _TOL_R 

479 

480 

481# def _ne0d(d, d0=_0_0): 

482# return fabs(d - d0) > _TOL_D 

483 

484 

485def _oblique2spherical(x, y): # 3.1.1 

486 # inverse oblique stereographic conformal projection from 

487 # C{RD (x, y)} to spherical C{(𝛷, 𝛬)}, see C++ function 

488 # sterea_e_inverse in U{Proj/src/projections/sterea.cpp 

489 # <https://Proj.org/en/stable/operations/projections/sterea.html>} 

490 x -= A0.X0 

491 y -= A0.Y0 

492 r = hypot(x, y) 

493 if r > _TOL_M: # x and y 

494 s0, c0 = A0.sincos2PHI0C 

495 sp, cp = sincos2(atan(r / A0.RK2) * _2_0) # psi atan2(r, A0.RK2) 

496 ca = sp * y / r 

497 xN = cp * c0 - ca * s0 

498 yN = sp * x / r 

499 zN = cp * s0 + ca * c0 

500 phiC = asin(zN) 

501 else: 

502 _, xN = A0.sincos2PHI0C 

503 yN = _0_0 

504 phiC = A0.PHI0C # asin(sin(PHI0C)) 

505 lamC = _atan3(yN, xN, x) + A0.LAM0C 

506 return phiC, lamC # -Capital 𝛷, 𝛬 

507 

508 

509def _spherical2ellipsoidal(phiC, lamC): # 3.1.2 

510 # inverse Gauss conformal projection from 

511 # spherical C{(𝛷, 𝛬)} to geodetic C{(lat, lon)} 

512 phi = phiC 

513 if PI_2 > phi > -PI_2: 

514 q = (A0.log_tan(phi) - A0.M0) / A0.N0 

515# w = A0.log_tan(phi) 

516 for _ in range(_TRIPS): # 3..6 

517 phi_ = phi 

518 phi = _atan_exp(A0.log_e_2(phi) + q) 

519 if fabs(phi - phi_) < _TOL_R: 

520 break 

521 lam = (lamC - A0.LAM0C) / A0.N0 + A0.LAM0 

522 lam += floor((PI - lam) / PI2) * PI2 

523 return map1(degrees, phi, lam) # lat, lon 

524 

525 

526def _spherical2oblique(phiC, lamC): # 2.4.2 

527 # oblique stereographic conformal projection 

528 # from spherical C{(𝛷, 𝛬)} to C{RD (x, y)} 

529 x = A0.X0 # 2.4.2g 

530 y = A0.Y0 # 2.4.2h 

531 a = phiC - A0.PHI0C # 𝛷 - 𝛷0 

532 b = lamC - A0.LAM0C # 𝛬 - 𝛬0 

533 if (_ne0(a) or _ne0(b)) and (_ne0(phiC, -A0.PHI0C) or 

534 _ne0(lamC, -A0.LAM0C + PI)): 

535 s0, c0 = A0.sincos2PHI0C # sin(𝛷0), cos(𝛷0) 

536 s, c = sincos2(phiC) # sin(𝛷), cos(𝛷) 

537 sp_22 = sin(a * _0_5)**2 + \ 

538 sin(b * _0_5)**2 * c * c0 # sin(𝜓/2)**2 

539 if EPS0 < sp_22 < EPS1: 

540 # r = 2kR * tan(𝜓/2) 

541 # q = r / (sin(𝜓/2) * cos(𝜓/2) * 2) 

542 # = 2kR * sin(𝜓/2) / (sin(𝜓/2) * cos(𝜓/2)**2 * 2) 

543 # = 2kR / (cos(𝜓/2)**2 * 2) 

544 # = 2kR / ((1 - sin(𝜓/2)**2) * 2) 

545 # = 2kR / (2 - sin(𝜓/2)**2 * 2) 

546 t = sp_22 * _2_0 # 0 < t < 2 

547 q = A0.RK2 / (_2_0 - t) 

548 x += q * (c * sin(b)) 

549 y += q * (s - s0 + s0 * t) / c0 

550 elif _eq0(a) and _eq0(b): 

551 pass 

552 else: # if _eq0(phiC, -A0.PHI0C) and _eq0(lamC, A0.LAM0C - PI): 

553 x = y = NAN 

554# else: 

555# raise RDNAPError(str((phiC, lamC))) 

556 return x, y 

557 

558 

559__all__ += _ALL_DOCS(_RDNAPbase) 

560__all__ += _ALL_OTHER(RDNAP2018v1, RDNAP2018v2, RDNAPError, 

561 Datum, Ellipsoid, LatLonDatum3Tuple) # passed along from PyGeodesy 

562 

563# **) MIT License 

564# 

565# Copyright (C) 2026-2026 -- mrJean1 at Gmail -- All Rights Reserved. 

566# 

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

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

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

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

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

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

573# 

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

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

576# 

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

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

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

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

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

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

583# OTHER DEALINGS IN THE SOFTWARE.