1

2# -*- coding: utf-8 -*-

3

4 u'''Iterators with options.

5

6 Iterator classes L{LatLon2PsxyIter} and L{PointsIter} to iterate

7 over iterables, lists, sets, tuples, etc. with optional loop-back to

8 the initial items, skipping of duplicate items and copying of the

9 iterated items.

10'''

11

12 from pygeodesy.basics import islistuple, issubclassof, len2, \

13 map2, _passarg

14# from pygeodesy.constants import _1_0 # from .utily

15 from pygeodesy.errors import _IndexError, LenError, PointsError, \

16 _TypeError, _ValueError

17# from pygeodesy.internals import _passarg # from .basics

18 from pygeodesy.interns import NN, _0_, _composite_, _few_, \

19 _latlon_, _points_, _too_

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

21 from pygeodesy.named import Fmt, _Named, property_RO

22 from pygeodesy.namedTuples import Point3Tuple, Points2Tuple

23# from pygeodesy.props import property_RO # from .named

24# from pygeodesy.streprs import Fmt # from .named

25 from pygeodesy.units import Int, Radius

26 from pygeodesy.utily import degrees2m, _Wrap, _1_0

27

28__all__ = _ALL_LAZY.iters

29__version__ = '23.12.14'

30

31_items_ = 'items'

32_iterNumpy2len = 1 # adjustable for testing purposes

33_NOTHING = object() # unique

34

35

36 class _BaseIter(_Named):

37 '''(INTERNAL) Iterator over items with loop-back and de-duplication.

38

39 @see: Luciano Ramalho, "Fluent Python", O'Reilly, 2016 p. 418+, 2022 p. 600+

40 '''

41 _closed = True

42 _copies = ()

43 _dedup = False

44 _Error = LenError

45 _items = None

46 _len = 0

47 _loop = ()

48 _looped = False

49 _name = _items_

50 _prev = _NOTHING

51 _wrap = False

52

53 def __init__(self, items, loop=0, dedup=False, Error=None, name=NN):

54 '''New iterator over an iterable of B{C{items}}.

55

56 @arg items: Iterable (any C{type}, except composites).

57 @kwarg loop: Number of loop-back items, also initial enumerate and

58 iterate index (non-negative C{int}).

59 @kwarg dedup: Skip duplicate items (C{bool}).

60 @kwarg Error: Error to raise (L{LenError}).

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

62

63 @raise Error: Invalid B{C{items}} or sufficient number of B{C{items}}.

64

65 @raise TypeError: Composite B{C{items}}.

66 '''

67 if dedup:

68 self._dedup = True

69 if issubclassof(Error, Exception):

70 self._Error = Error

71 if name:

72 self.rename(name)

73

74 if islistuple(items): # range in Python 2

75 self._items = items

76 elif _MODS.booleans.isBoolean(items):

77 raise _TypeError(points=_composite_)

78# XXX if hasattr(items, 'next') or hasattr(items, '__length_hint__'):

79# XXX # handle reversed, iter, etc. items types

80 self._iter = iter(items)

81 self._indx = -1

82 if Int(loop) > 0:

83 try:

84 self._loop = tuple(self.next for _ in range(loop))

85 if self.loop != loop:

86 raise RuntimeError # force Error

87 except (RuntimeError, StopIteration):

88 raise self._Error(self.name, self.loop, txt=_too_(_few_))

89

90 @property_RO

91 def copies(self):

92 '''Get the saved copies, if any (C{tuple} or C{list}) and only I{once}.

93 '''

94 cs = self._copies

95 if cs:

96 self._copies = ()

97 return cs

98

99 @property_RO

100 def dedup(self):

101 '''Get the de-duplication setting (C{bool}).

102 '''

103 return self._dedup

104

105 def enumerate(self, closed=False, copies=False, dedup=False):

106 '''Yield all items, each as a 2-tuple C{(index, item)}.

107

108 @kwarg closed: Loop back to the first B{C{point(s)}}.

109 @kwarg copies: Make a copy of all B{C{items}} (C{bool}).

110 @kwarg dedup: Set de-duplication in loop-back (C{bool}).

111 '''

112 for item in self.iterate(closed=closed, copies=copies, dedup=dedup):

113 yield self._indx, item

114

115 def __getitem__(self, index):

116 '''Get the item(s) at the given B{C{index}} or C{slice}.

117

118 @raise IndexError: Invalid B{C{index}}, beyond B{C{loop}}.

119 '''

120 t = self._items or self._copies or self._loop

121 try: # Luciano Ramalho, "Fluent Python", O'Reilly, 2016 p. 293+, 2022 p. 408+

122 if isinstance(index, slice):

123 return t[index.start:index.stop:index.step]

124 else:

125 return t[index]

126 except IndexError as x:

127 t = Fmt.SQUARE(self.name, index)

128 raise _IndexError(str(x), txt=t, cause=x)

129

130 def __iter__(self): # PYCHOK no cover

131 '''Make this iterator C{iterable}.

132 '''

133 # Luciano Ramalho, "Fluent Python", O'Reilly, 2016 p. 421, 2022 p. 604+

134 return self.iterate() # XXX or self?

135

136 def iterate(self, closed=False, copies=False, dedup=False):

137 '''Yield all items, each as C{item}.

138

139 @kwarg closed: Loop back to the first B{C{point(s)}}.

140 @kwarg copies: Make a copy of all B{C{items}} (C{bool}).

141 @kwarg dedup: Set de-duplication in loop-back (C{bool}).

142

143 @raise Error: Using C{B{closed}=True} without B{C{loop}}-back.

144 '''

145 if closed and not self.loop:

146 raise self._Error(closed=closed, loop=self.loop)

147

148 if copies:

149 if self._items:

150 self._copies = self._items

151 self._items = _copy = None

152 else:

153 self._copies = list(self._loop)

154 _copy = self._copies.append

155 else: # del B{C{items}} reference

156 self._items = _copy = None

157

158 self._closed = closed

159 self._looped = False

160 if self._iter:

161 try:

162 _next_ = self.next_

163 if _copy:

164 while True:

165 item = _next_(dedup=dedup)

166 _copy(item)

167 yield item

168 else:

169 while True:

170 yield _next_(dedup=dedup)

171 except StopIteration:

172 self._iter = () # del self._iter, prevent re-iterate

173

174 def __len__(self):

175 '''Get the number of items seen so far.

176 '''

177 return self._len

178

179 @property_RO

180 def loop(self):

181 '''Get the B{C{loop}} setting (C{int}), C{0} for non-loop-back.

182 '''

183 return len(self._loop)

184

185 @property_RO

186 def looped(self):

187 '''In this C{Iter}ator in loop-back? (C{bool}).

188 '''

189 return self._looped

190

191 @property_RO

192 def next(self):

193 '''Get the next item.

194 '''

195 return self._next_dedup() if self._dedup else self._next(False)

196

197# __next__ # NO __next__ AND __iter__ ... see Luciano Ramalho,

198# # "Fluent Python", O'Reilly, 2016 p. 426, 2022 p. 610

199

200 def next_(self, dedup=False):

201 '''Return the next item.

202

203 @kwarg dedup: Set de-duplication for loop-back (C{bool}).

204 '''

205 return self._next_dedup() if self._dedup else self._next(dedup)

206

207 def _next(self, dedup):

208 '''Return the next item, regardless.

209

210 @arg dedup: Set de-duplication for loop-back (C{bool}).

211 '''

212 try:

213 self._indx += 1

214 self._len = self._indx # max(_len, _indx)

215 self._prev = item = next(self._iter)

216 return item

217 except StopIteration:

218 pass

219 if self._closed and self._loop: # loop back

220 self._dedup = bool(dedup or self._dedup)

221 self._indx = 0

222 self._iter = iter(self._loop)

223 self._loop = ()

224 self._looped = True

225 return next(self._iter)

226

227 def _next_dedup(self):

228 '''Return the next item, different from the previous one.

229 '''

230 prev = self._prev

231 item = self._next(True)

232 if prev is not _NOTHING:

233 while item == prev:

234 item = self._next(True)

235 return item

236

237

238 class PointsIter(_BaseIter):

239 '''Iterator for C{points} with optional loop-back and copies.

240 '''

241 _base = None

242 _Error = PointsError

243

244 def __init__(self, points, loop=0, base=None, dedup=False, wrap=False, name=NN):

245 '''New L{PointsIter} iterator.

246

247 @arg points: C{Iterable} or C{list}, C{sequence}, C{set}, C{tuple},

248 etc. (C{point}s).

249 @kwarg loop: Number of loop-back points, also initial C{enumerate} and

250 C{iterate} index (non-negative C{int}).

251 @kwarg base: Optional B{C{points}} instance for type checking (C{any}).

252 @kwarg dedup: Skip duplicate points (C{bool}).

253 @kwarg wrap: If C{True}, wrap or I{normalize} the enum-/iterated

254 B{C{points}} (C{bool}).

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

256

257 @raise PointsError: Insufficient number of B{C{points}}.

258

259 @raise TypeError: Some B{C{points}} are not B{C{base}}.

260 '''

261 _BaseIter.__init__(self, points, loop=loop, dedup=dedup, name=name or _points_)

262

263 if base and not (isNumpy2(points) or isTuple2(points)):

264 self._base = base

265 if wrap:

266 self._wrap = True

267

268 def enumerate(self, closed=False, copies=False): # PYCHOK signature

269 '''Iterate and yield each point as a 2-tuple C{(index, point)}.

270

271 @kwarg closed: Loop back to the first B{C{point(s)}}, de-dup'ed (C{bool}).

272 @kwarg copies: Save a copy of all B{C{points}} (C{bool}).

273

274 @raise PointsError: Insufficient number of B{C{points}} or using

275 C{B{closed}=True} without B{C{loop}}-back.

276

277 @raise TypeError: Some B{C{points}} are not B{C{base}}-compatible.

278 '''

279 for p in self.iterate(closed=closed, copies=copies):

280 yield self._indx, p

281

282 def iterate(self, closed=False, copies=False): # PYCHOK signature

283 '''Iterate through all B{C{points}} starting at index C{loop}.

284

285 @kwarg closed: Loop back to the first B{C{point(s)}}, de-dup'ed (C{bool}).

286 @kwarg copies: Save a copy of all B{C{points}} (C{bool}).

287

288 @raise PointsError: Insufficient number of B{C{points}} or using

289 C{B{closed}=True} without B{C{loop}}-back.

290

291 @raise TypeError: Some B{C{points}} are not B{C{base}}-compatible.

292 '''

293 if self._base:

294 _oth = self._base.others

295 _fmt = Fmt.SQUARE(points=0).replace

296 else:

297 _oth = _fmt = None

298

299 n = self.loop if self._iter else 0

300 _p = _Wrap.point if self._wrap else _passarg # and _Wrap.normal is not None

301 for p in _BaseIter.iterate(self, closed=closed, copies=copies, dedup=closed):

302 if _oth:

303 _oth(p, name=_fmt(_0_, str(self._indx)), up=2)

304 yield _p(p)

305 n += 1

306 if n < (4 if closed else 2):

307 raise self._Error(self.name, n, txt=_too_(_few_))

308

309

310 class LatLon2PsxyIter(PointsIter):

311 '''Iterate and convert for C{points} with optional loop-back and copies.

312 '''

313 _deg2m = None

314 _radius = None # keep degrees

315 _wrap = True

316

317 def __init__(self, points, loop=0, base=None, wrap=True, radius=None,

318 dedup=False, name=_latlon_):

319 '''New L{LatLon2PsxyIter} iterator.

320

321 @note: The C{LatLon} latitude is considered the I{pseudo-y} and

322 longitude the I{pseudo-x} coordinate, like L{LatLon2psxy}.

323

324 @arg points: C{Iterable} or C{list}, C{sequence}, C{set}, C{tuple},

325 etc. (C{LatLon}[]).

326 @kwarg loop: Number of loop-back points, also initial C{enumerate} and

327 C{iterate} index (non-negative C{int}).

328 @kwarg base: Optional B{C{points}} instance for type checking (C{any}).

329 @kwarg wrap: If C{True}, wrap or I{normalize} the enum-/iterated

330 B{C{points}} (C{bool}).

331 @kwarg radius: Mean earth radius (C{meter}) for conversion from

332 C{degrees} to C{meter} (or C{radians} if C{B{radius}=1}).

333 @kwarg dedup: Skip duplicate points (C{bool}).

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

335

336 @raise PointsError: Insufficient number of B{C{points}}.

337

338 @raise TypeError: Some B{C{points}} are not B{C{base}}-compatible.

339 '''

340 PointsIter.__init__(self, points, loop=loop, base=base, dedup=dedup, name=name)

341 if not wrap:

342 self._wrap = False

343 if radius:

344 self._radius = r = Radius(radius)

345 self._deg2m = degrees2m(_1_0, r)

346

347 def __getitem__(self, index):

348 '''Get the point(s) at the given B{C{index}} or C{slice}.

349

350 @raise IndexError: Invalid B{C{index}}, beyond B{C{loop}}.

351 '''

352 ll = PointsIter.__getitem__(self, index)

353 if isinstance(index, slice):

354 return map2(self._point3Tuple, ll)

355 else:

356 return self._point3Tuple(ll)

357

358 def enumerate(self, closed=False, copies=False): # PYCHOK signature

359 '''Iterate and yield each point as a 2-tuple C{(index, L{Point3Tuple})}.

360

361 @kwarg closed: Loop back to the first B{C{point(s)}}, de-dup'ed (C{bool}).

362 @kwarg copies: Save a copy of all B{C{points}} (C{bool}).

363

364 @raise PointsError: Insufficient number of B{C{points}} or using

365 C{B{closed}=True} without B{C{loop}}-back.

366

367 @raise TypeError: Some B{C{points}} are not B{C{base}}-compatible.

368 '''

369 return PointsIter.enumerate(self, closed=closed, copies=copies)

370

371 def iterate(self, closed=False, copies=False): # PYCHOK signature

372 '''Iterate the B{C{points}} starting at index B{C{loop}} and

373 yield each as a L{Point3Tuple}C{(x, y, ll)}.

374

375 @kwarg closed: Loop back to the first B{C{point(s)}}, de-dup'ed (C{bool}).

376 @kwarg copies: Save a copy of all B{C{points}} (C{bool}).

377

378 @raise PointsError: Insufficient number of B{C{points}} or using

379 C{B{closed}=True} without B{C{loop}}-back.

380

381 @raise TypeError: Some B{C{points}} are not B{C{base}}-compatible.

382 '''

383 if self._deg2m not in (None, _1_0):

384 _p3 = self._point3Tuple

385 else:

386 def _p3(ll): # PYCHOK redef

387 return Point3Tuple(ll.lon, ll.lat, ll)

388

389 for ll in PointsIter.iterate(self, closed=closed, copies=copies):

390 yield _p3(ll)

391

392 def _point3Tuple(self, ll):

393 '''(INTERNAL) Create a L{Point3Tuple} for point B{C{ll}}.

394 '''

395 x, y = ll.lon, ll.lat # note, x, y = lon, lat

396 d = self._deg2m

397 if d: # convert degrees

398 x *= d

399 y *= d

400 return Point3Tuple(x, y, ll)

401

402

403 def _imdex2(closed, n): # PYCHOK by .clipy

404 '''(INTERNAL) Return first and second index of C{range(B{n})}.

405 '''

406 return (n-1, 0) if closed else (0, 1)

407

408

409 def isNumpy2(obj):

410 '''Check for a B{C{Numpy2LatLon}} points wrapper.

411

412 @arg obj: The object (any C{type}).

413

414 @return: C{True} if B{C{obj}} is a B{C{Numpy2LatLon}}

415 instance, C{False} otherwise.

416 '''

417 # isinstance(self, (Numpy2LatLon, ...))

418 return getattr(obj, isNumpy2.__name__, False)

419

420

421 def isPoints2(obj):

422 '''Check for a B{C{LatLon2psxy}} points wrapper.

423

424 @arg obj: The object (any C{type}).

425

426 @return: C{True} if B{C{obj}} is a B{C{LatLon2psxy}}

427 instance, C{False} otherwise.

428 '''

429 # isinstance(self, (LatLon2psxy, ...))

430 return getattr(obj, isPoints2.__name__, False)

431

432

433 def isTuple2(obj):

434 '''Check for a B{C{Tuple2LatLon}} points wrapper.

435

436 @arg obj: The object (any).

437

438 @return: C{True} if B{C{obj}} is a B{C{Tuple2LatLon}}

439 instance, C{False} otherwise.

440 '''

441 # isinstance(self, (Tuple2LatLon, ...))

442 return getattr(obj, isTuple2.__name__, False)

443

444

445 def iterNumpy2(obj):

446 '''Iterate over Numpy2 wrappers or other sequences exceeding

447 the threshold.

448

449 @arg obj: Points array, list, sequence, set, etc. (any).

450

451 @return: C{True} do, C{False} don't iterate.

452 '''

453 try:

454 return isNumpy2(obj) or len(obj) > _iterNumpy2len

455 except TypeError:

456 return False

457

458

459 def iterNumpy2over(n=None):

460 '''Get or set the L{iterNumpy2} threshold.

461

462 @kwarg n: Optional, new threshold (C{int}).

463

464 @return: Previous threshold (C{int}).

465

466 @raise ValueError: Invalid B{C{n}}.

467 '''

468 global _iterNumpy2len

469 p = _iterNumpy2len

470 if n is not None:

471 try:

472 i = int(n)

473 if i > 0:

474 _iterNumpy2len = i

475 else:

476 raise ValueError

477 except (TypeError, ValueError):

478 raise _ValueError(n=n)

479 return p

480

481

482 def points2(points, closed=True, base=None, Error=PointsError):

483 '''Check a path or polygon represented by points.

484

485 @arg points: The path or polygon points (C{LatLon}[])

486 @kwarg closed: Optionally, consider the polygon closed,

487 ignoring any duplicate or closing final

488 B{C{points}} (C{bool}).

489 @kwarg base: Optionally, check all B{C{points}} against

490 this base class, if C{None} don't check.

491 @kwarg Error: Exception to raise (C{ValueError}).

492

493 @return: A L{Points2Tuple}C{(number, points)} with the number

494 of points and the points C{list} or C{tuple}.

495

496 @raise PointsError: Insufficient number of B{C{points}}.

497

498 @raise TypeError: Some B{C{points}} are not B{C{base}}

499 compatible or composite B{C{points}}.

500 '''

501 if _MODS.booleans.isBoolean(points):

502 raise Error(points=points, txt=_composite_)

503

504 n, points = len2(points)

505

506 if closed:

507 # remove duplicate or closing final points

508 while n > 1 and points[n-1] in (points[0], points[n-2]):

509 n -= 1

510 # XXX following line is unneeded if points

511 # are always indexed as ... i in range(n)

512 points = points[:n] # XXX numpy.array slice is a view!

513

514 if n < (3 if closed else 1):

515 raise Error(points=n, txt=_too_(_few_))

516

517 if base and not (isNumpy2(points) or isTuple2(points)):

518 for i in range(n):

519 base.others(points[i], name=Fmt.SQUARE(points=i))

520

521 return Points2Tuple(n, points)

522

523

524__all__ += _ALL_DOCS(_BaseIter)

525

526# **) MIT License

527#

528# Copyright (C) 2016-2024 -- mrJean1 at Gmail -- All Rights Reserved.

529#

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

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

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

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

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

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

536#

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

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

539#

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

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

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

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

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

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

546# OTHER DEALINGS IN THE SOFTWARE.