Coverage for pygeodesy/basics.py: 95%

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1 

2# -*- coding: utf-8 -*- 

3 

4u'''Some, basic definitions, functions and dependencies. 

5 

6Use env variable C{PYGEODESY_XPACKAGES} to avoid import of dependencies 

7C{geographiclib}, C{numpy} and/or C{scipy}. Set C{PYGEODESY_XPACKAGES} 

8to a comma-separated list of package names to be excluded from import. 

9''' 

10# make sure int/int division yields float quotient 

11from __future__ import division 

12division = 1 / 2 # .albers, .azimuthal, .constants, etc., .utily 

13if not division: 

14 raise ImportError('%s 1/2 == %s' % ('division', division)) 

15del division 

16 

17from pygeodesy.errors import _AttributeError, _ImportError, _NotImplementedError, \ 

18 _TypeError, _TypesError, _ValueError, _xAssertionError, \ 

19 _xkwds_get 

20from pygeodesy.interns import MISSING, NN, _1_, _by_, _COMMA_, _DOT_, _DEPRECATED_, \ 

21 _ELLIPSIS4_, _enquote, _EQUAL_, _in_, _invalid_, _N_A_, \ 

22 _not_scalar_, _SPACE_, _UNDER_, _version_, _version_info 

23from pygeodesy.lazily import _ALL_LAZY, _ALL_MODS as _MODS, _FOR_DOCS, \ 

24 _getenv, LazyImportError, _sys, _sys_version_info2 

25 

26from copy import copy as _copy, deepcopy as _deepcopy 

27from math import copysign as _copysign 

28import inspect as _inspect 

29 

30__all__ = _ALL_LAZY.basics 

31__version__ = '24.02.21' 

32 

33_0_0 = 0.0 # in .constants 

34_below_ = 'below' 

35_list_tuple_types = (list, tuple) 

36_list_tuple_set_types = (list, tuple, set) 

37_odd_ = 'odd' 

38_PYGEODESY_XPACKAGES_ = 'PYGEODESY_XPACKAGES' 

39_required_ = 'required' 

40 

41try: # Luciano Ramalho, "Fluent Python", O'Reilly, 2016 p. 395, 2022 p. 577+ 

42 from numbers import Integral as _Ints, Real as _Scalars # .units 

43except ImportError: 

44 try: 

45 _Ints = int, long # int objects (C{tuple}) 

46 except NameError: # Python 3+ 

47 _Ints = int, # int objects (C{tuple}) 

48 _Scalars = _Ints + (float,) 

49 

50try: 

51 try: # use C{from collections.abc import ...} in Python 3.9+ 

52 from collections.abc import Sequence as _Sequence # in .points 

53 except ImportError: # no .abc in Python 3.8- and 2.7- 

54 from collections import Sequence as _Sequence # in .points 

55 if isinstance([], _Sequence) and isinstance((), _Sequence): 

56 # and isinstance(range(1), _Sequence): 

57 _Seqs = _Sequence 

58 else: 

59 raise ImportError() # _AssertionError 

60except ImportError: 

61 _Sequence = tuple # immutable for .points._Basequence 

62 _Seqs = list, _Sequence # range for function len2 below 

63 

64 

65def _passarg(arg): # in .auxilats.auxLat 

66 '''(INTERNAL) Helper, no-op. 

67 ''' 

68 return arg 

69 

70 

71def _passargs(*args): # in .utily 

72 '''(INTERNAL) Helper, no-op. 

73 ''' 

74 return args 

75 

76 

77try: 

78 _Bytes = unicode, bytearray # PYCHOK expected 

79 _Strs = basestring, str # XXX , bytes 

80 str2ub = ub2str = _passarg # avoids UnicodeDecodeError 

81 

82 def _Xstr(exc): # PYCHOK no cover 

83 '''I{Invoke only with caught ImportError} B{C{exc}}. 

84 

85 C{... "can't import name _distributor_init" ...} 

86 

87 only for C{numpy}, C{scipy} import errors occurring 

88 on arm64 Apple Silicon running macOS' Python 2.7.16? 

89 ''' 

90 t = str(exc) 

91 if '_distributor_init' in t: 

92 from sys import exc_info 

93 from traceback import extract_tb 

94 tb = exc_info()[2] # 3-tuple (type, value, traceback) 

95 t4 = extract_tb(tb, 1)[0] # 4-tuple (file, line, name, 'import ...') 

96 t = _SPACE_("can't", t4[3] or _N_A_) 

97 del tb, t4 

98 return t 

99 

100except NameError: # Python 3+ 

101 from pygeodesy.interns import _utf_8_ 

102 

103 _Bytes = bytes, bytearray 

104 _Strs = str, # tuple 

105 _Xstr = str 

106 

107 def str2ub(sb): 

108 '''Convert C{str} to C{unicode bytes}. 

109 ''' 

110 if isinstance(sb, _Strs): 

111 sb = sb.encode(_utf_8_) 

112 return sb 

113 

114 def ub2str(ub): 

115 '''Convert C{unicode bytes} to C{str}. 

116 ''' 

117 if isinstance(ub, _Bytes): 

118 ub = str(ub.decode(_utf_8_)) 

119 return ub 

120 

121 

122def _args_kwds_names(func): 

123 '''(INTERNAL) Get a C{func}'s args and kwds names, including 

124 C{self} for methods. 

125 

126 @note: Python 2 may I{not} include the C{*args} nor the 

127 C{**kwds} names. 

128 ''' 

129 try: 

130 args_kwds = _inspect.signature(func).parameters.keys() 

131 except AttributeError: # .signature new Python 3+ 

132 args_kwds = _inspect.getargspec(func).args 

133 return tuple(args_kwds) 

134 

135 

136def clips(sb, limit=50, white=NN): 

137 '''Clip a string to the given length limit. 

138 

139 @arg sb: String (C{str} or C{bytes}). 

140 @kwarg limit: Length limit (C{int}). 

141 @kwarg white: Optionally, replace all whitespace (C{str}). 

142 

143 @return: The clipped or unclipped B{C{sb}}. 

144 ''' 

145 T = type(sb) 

146 if len(sb) > limit > 8: 

147 h = limit // 2 

148 sb = T(_ELLIPSIS4_).join((sb[:h], sb[-h:])) 

149 if white: # replace whitespace 

150 sb = T(white).join(sb.split()) 

151 return sb 

152 

153 

154def copysign0(x, y): 

155 '''Like C{math.copysign(x, y)} except C{zero}, I{unsigned}. 

156 

157 @return: C{math.copysign(B{x}, B{y})} if B{C{x}} else 

158 C{type(B{x})(0)}. 

159 ''' 

160 return _copysign(x, (y if y else 0)) if x else copytype(0, x) 

161 

162 

163def copytype(x, y): 

164 '''Return the value of B{x} as C{type} of C{y}. 

165 

166 @return: C{type(B{y})(B{x})}. 

167 ''' 

168 return type(y)(x if x else _0_0) 

169 

170 

171def halfs2(str2): 

172 '''Split a string in 2 halfs. 

173 

174 @arg str2: String to split (C{str}). 

175 

176 @return: 2-Tuple C{(_1st, _2nd)} half (C{str}). 

177 

178 @raise ValueError: Zero or odd C{len(B{str2})}. 

179 ''' 

180 h, r = divmod(len(str2), 2) 

181 if r or not h: 

182 raise _ValueError(str2=str2, txt=_odd_) 

183 return str2[:h], str2[h:] 

184 

185 

186def int1s(x): 

187 '''Count the number of 1-bits in an C{int}, I{unsigned}. 

188 

189 @note: C{int1s(-B{x}) == int1s(abs(B{x}))}. 

190 ''' 

191 try: 

192 return x.bit_count() # Python 3.10+ 

193 except AttributeError: 

194 # bin(-x) = '-' + bin(abs(x)) 

195 return bin(x).count(_1_) 

196 

197 

198def isbool(obj): 

199 '''Check whether an object is C{bool}ean. 

200 

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

202 

203 @return: C{True} if B{C{obj}} is C{bool}ean, 

204 C{False} otherwise. 

205 ''' 

206 return isinstance(obj, bool) # and (obj is False 

207# or obj is True) 

208 

209assert not (isbool(1) or isbool(0) or isbool(None)) # PYCHOK 2 

210 

211if _FOR_DOCS: # XXX avoid epydoc Python 2.7 error 

212 

213 def isclass(obj): 

214 '''Return C{True} if B{C{obj}} is a C{class} or C{type}. 

215 

216 @see: Python's C{inspect.isclass}. 

217 ''' 

218 return _inspect.isclass(obj) 

219else: 

220 isclass = _inspect.isclass 

221 

222 

223def isCartesian(obj, ellipsoidal=None): 

224 '''Is B{C{obj}} some C{Cartesian}? 

225 

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

227 @kwarg ellipsoidal: If C{None}, return the type of any C{Cartesian}, 

228 if C{True}, only an ellipsoidal C{Cartesian type} 

229 or if C{False}, only a spherical C{Cartesian type}. 

230 

231 @return: C{type(B{obj}} if B{C{obj}} is a C{Cartesian} instance of 

232 the required type, C{False} if a C{Cartesian} of an other 

233 type or C{None} otherwise. 

234 ''' 

235 if ellipsoidal is not None: 

236 try: 

237 return obj.ellipsoidalCartesian if ellipsoidal else obj.sphericalCartesian 

238 except AttributeError: 

239 return None 

240 return isinstanceof(obj, _MODS.cartesianBase.CartesianBase) 

241 

242 

243def iscomplex(obj): 

244 '''Check whether an object is a C{complex} or complex C{str}. 

245 

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

247 

248 @return: C{True} if B{C{obj}} is C{complex}, otherwise 

249 C{False}. 

250 ''' 

251 try: # hasattr('conjugate'), hasattr('real') and hasattr('imag') 

252 return isinstance(obj, complex) or (isstr(obj) 

253 and isinstance(complex(obj), complex)) # numbers.Complex? 

254 except (TypeError, ValueError): 

255 return False 

256 

257 

258def isDEPRECATED(obj): 

259 '''Return C{True} if C{B{obj}} is a C{DEPRECATED} class, method 

260 or function, C{False} if not or C{None} if undetermined. 

261 ''' 

262 try: # XXX inspect.getdoc(obj) 

263 return bool(obj.__doc__.lstrip().startswith(_DEPRECATED_)) 

264 except AttributeError: 

265 return None 

266 

267 

268def isfloat(obj): 

269 '''Check whether an object is a C{float} or float C{str}. 

270 

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

272 

273 @return: C{True} if B{C{obj}} is a C{float}, otherwise 

274 C{False}. 

275 ''' 

276 try: 

277 return isinstance( obj, float) or (isstr(obj) 

278 and isinstance(float(obj), float)) 

279 except (TypeError, ValueError): 

280 return False 

281 

282 

283try: 

284 isidentifier = str.isidentifier # Python 3, must be str 

285except AttributeError: # Python 2- 

286 

287 def isidentifier(obj): 

288 '''Return C{True} if B{C{obj}} is a Python identifier. 

289 ''' 

290 return bool(obj and isstr(obj) 

291 and obj.replace(_UNDER_, NN).isalnum() 

292 and not obj[:1].isdigit()) 

293 

294 

295def isinstanceof(obj, *classes): 

296 '''Is B{C{ob}} an instance of one of the C{classes}? 

297 

298 @arg obj: The instance (any C{type}). 

299 @arg classes: One or more classes (C{class}). 

300 

301 @return: C{type(B{obj}} if B{C{obj}} is an instance 

302 of the B{C{classes}}, C{None} otherwise. 

303 ''' 

304 return type(obj) if isinstance(obj, classes) else None 

305 

306 

307def isint(obj, both=False): 

308 '''Check for C{int} type or an integer C{float} value. 

309 

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

311 @kwarg both: If C{true}, check C{float} and L{Fsum} 

312 type and value (C{bool}). 

313 

314 @return: C{True} if B{C{obj}} is C{int} or I{integer} 

315 C{float} or L{Fsum}, C{False} otherwise. 

316 

317 @note: Both C{isint(True)} and C{isint(False)} return 

318 C{False} (and no longer C{True}). 

319 ''' 

320 if isinstance(obj, _Ints) and not isbool(obj): 

321 return True 

322 elif both: # and isinstance(obj, (float, Fsum)) 

323 try: # NOT , _Scalars) to include Fsum! 

324 return obj.is_integer() 

325 except AttributeError: 

326 pass # XXX float(int(obj)) == obj? 

327 return False 

328 

329 

330try: 

331 from keyword import iskeyword # Python 2.7+ 

332except ImportError: 

333 

334 def iskeyword(unused): 

335 '''Not Implemented, C{False} always. 

336 ''' 

337 return False 

338 

339 

340def isLatLon(obj, ellipsoidal=None): 

341 '''Is B{C{obj}} some C{LatLon}? 

342 

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

344 @kwarg ellipsoidal: If C{None}, return the type of any C{LatLon}, 

345 if C{True}, only an ellipsoidal C{LatLon type} 

346 or if C{False}, only a spherical C{LatLon type}. 

347 

348 @return: C{type(B{obj}} if B{C{obj}} is a C{LatLon} instance of 

349 the required type, C{False} if a C{LatLon} of an other 

350 type or {None} otherwise. 

351 ''' 

352 if ellipsoidal is not None: 

353 try: 

354 return obj.ellipsoidalLatLon if ellipsoidal else obj.sphericalLatLon 

355 except AttributeError: 

356 return None 

357 return isinstanceof(obj, _MODS.latlonBase.LatLonBase) 

358 

359 

360def islistuple(obj, minum=0): 

361 '''Check for list or tuple C{type} with a minumal length. 

362 

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

364 @kwarg minum: Minimal C{len} required C({int}). 

365 

366 @return: C{True} if B{C{obj}} is C{list} or C{tuple} with 

367 C{len} at least B{C{minum}}, C{False} otherwise. 

368 ''' 

369 return isinstance(obj, _list_tuple_types) and len(obj) >= minum 

370 

371 

372def isNvector(obj, ellipsoidal=None): 

373 '''Is B{C{obj}} some C{Nvector}? 

374 

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

376 @kwarg ellipsoidal: If C{None}, return the type of any C{Nvector}, 

377 if C{True}, only an ellipsoidal C{Nvector type} 

378 or if C{False}, only a spherical C{Nvector type}. 

379 

380 @return: C{type(B{obj}} if B{C{obj}} is an C{Nvector} instance of 

381 the required type, C{False} if an C{Nvector} of an other 

382 type or {None} otherwise. 

383 ''' 

384 if ellipsoidal is not None: 

385 try: 

386 return obj.ellipsoidalNvector if ellipsoidal else obj.sphericalNvector 

387 except AttributeError: 

388 return None 

389 return isinstanceof(obj, _MODS.nvectorBase.NvectorBase) 

390 

391 

392def isodd(x): 

393 '''Is B{C{x}} odd? 

394 

395 @arg x: Value (C{scalar}). 

396 

397 @return: C{True} if B{C{x}} is odd, 

398 C{False} otherwise. 

399 ''' 

400 return bool(int(x) & 1) # == bool(int(x) % 2) 

401 

402 

403def isscalar(obj): 

404 '''Check for scalar types. 

405 

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

407 

408 @return: C{True} if B{C{obj}} is C{scalar}, C{False} otherwise. 

409 ''' 

410 return isinstance(obj, _Scalars) and not isbool(obj) 

411 

412 

413def issequence(obj, *excls): 

414 '''Check for sequence types. 

415 

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

417 @arg excls: Classes to exclude (C{type}), all positional. 

418 

419 @note: Excluding C{tuple} implies excluding C{namedtuple}. 

420 

421 @return: C{True} if B{C{obj}} is a sequence, C{False} otherwise. 

422 ''' 

423 return isinstance(obj, _Seqs) and not (excls and isinstance(obj, excls)) 

424 

425 

426def isstr(obj): 

427 '''Check for string types. 

428 

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

430 

431 @return: C{True} if B{C{obj}} is C{str}, C{False} otherwise. 

432 ''' 

433 return isinstance(obj, _Strs) 

434 

435 

436def issubclassof(Sub, *Supers): 

437 '''Check whether a class is a sub-class of some other class(es). 

438 

439 @arg Sub: The sub-class (C{class}). 

440 @arg Supers: One or more C(super) classes (C{class}). 

441 

442 @return: C{True} if B{C{Sub}} is a sub-class of any B{C{Supers}}, 

443 C{False} if not (C{bool}) or C{None} if B{C{Sub}} is not 

444 a class or if no B{C{Supers}} are given or none of those 

445 are a class. 

446 ''' 

447 if isclass(Sub): 

448 t = tuple(S for S in Supers if isclass(S)) 

449 if t: 

450 return bool(issubclass(Sub, t)) 

451 return None 

452 

453 

454def itemsorted(adict, *items_args, **asorted_reverse): 

455 '''Return the items of C{B{adict}} sorted I{alphabetically, 

456 case-insensitively} and in I{ascending} order. 

457 

458 @arg items_args: Optional positional argument(s) for method 

459 C{B{adict}.items(B*{items_args})}. 

460 @kwarg asorted_reverse: Use keyword argument C{B{asorted}=False} 

461 for I{case-sensitive} sorting and C{B{reverse}=True} 

462 for results in C{descending} order. 

463 ''' 

464 def _ins(item): 

465 return item[0].lower() 

466 

467 def _key_rev(asorted=True, reverse=False): 

468 return (_ins if asorted else None), reverse 

469 

470 key, rev = _key_rev(**asorted_reverse) 

471 items = adict.items(*items_args) if items_args else adict.items() 

472 return sorted(items, reverse=rev, key=key) 

473 

474 

475def len2(items): 

476 '''Make built-in function L{len} work for generators, iterators, 

477 etc. since those can only be started exactly once. 

478 

479 @arg items: Generator, iterator, list, range, tuple, etc. 

480 

481 @return: 2-Tuple C{(n, items)} of the number of items (C{int}) 

482 and the items (C{list} or C{tuple}). 

483 ''' 

484 if not isinstance(items, _Seqs): # NOT hasattr(items, '__len__'): 

485 items = list(items) 

486 return len(items), items 

487 

488 

489def map1(fun1, *xs): # XXX map_ 

490 '''Apply a single-argument function to each B{C{xs}} and 

491 return a C{tuple} of results. 

492 

493 @arg fun1: 1-Arg function (C{callable}). 

494 @arg xs: Arguments (C{any positional}). 

495 

496 @return: Function results (C{tuple}). 

497 ''' 

498 return tuple(map(fun1, xs)) 

499 

500 

501def map2(fun, *xs): 

502 '''Apply a function to arguments and return a C{tuple} of results. 

503 

504 Unlike Python 2's built-in L{map}, Python 3+ L{map} returns a 

505 L{map} object, an iterator-like object which generates the 

506 results only once. Converting the L{map} object to a tuple 

507 maintains the Python 2 behavior. 

508 

509 @arg fun: Function (C{callable}). 

510 @arg xs: Arguments (C{list, tuple, ...}). 

511 

512 @return: Function results (C{tuple}). 

513 ''' 

514 return tuple(map(fun, *xs)) 

515 

516 

517def neg(x, neg0=None): 

518 '''Negate C{x} and optionally, negate C{0.0} and C{-0.0}. 

519 

520 @kwarg neg0: Defines the return value for zero C{B{x}}: if C{None} 

521 return C{0.0}, if C{True} return C{NEG0 if B{x}=0.0} 

522 and C{0.0 if B{x}=NEG0} or if C{False} return C{B{x}} 

523 I{as-is} (C{bool} or C{None}). 

524 

525 @return: C{-B{x} if B{x} else 0.0, NEG0 or B{x}}. 

526 ''' 

527 return (-x) if x else (_0_0 if neg0 is None else (x if not neg0 else 

528 (_0_0 if signBit(x) else _MODS.constants.NEG0))) 

529 

530 

531def neg_(*xs): 

532 '''Negate all C{xs} with L{neg}. 

533 

534 @return: A C{map(neg, B{xs})}. 

535 ''' 

536 return map(neg, xs) 

537 

538 

539def _req_d_by(where, **name): # in .basics 

540 '''(INTERNAL) Get the fully qualified name. 

541 ''' 

542 m = _MODS.named.modulename(where, prefixed=True) 

543 if name: 

544 n = _xkwds_get(name, name=NN) 

545 if n: 

546 m = _DOT_(m, n) 

547 return _SPACE_(_required_, _by_, m) 

548 

549 

550def _reverange(n, stop=-1, step=-1): 

551 '''(INTERNAL) Reversed range yielding C{n-1, n-1-step, ..., stop+1}. 

552 ''' 

553 return range(n - 1, stop, step) 

554 

555 

556def signBit(x): 

557 '''Return C{signbit(B{x})}, like C++. 

558 

559 @return: C{True} if C{B{x} < 0} or C{NEG0} (C{bool}). 

560 ''' 

561 return x < 0 or _MODS.constants.isneg0(x) 

562 

563 

564def _signOf(x, ref): # in .fsums 

565 '''(INTERNAL) Return the sign of B{C{x}} versus B{C{ref}}. 

566 ''' 

567 return +1 if x > ref else (-1 if x < ref else 0) 

568 

569 

570def signOf(x): 

571 '''Return sign of C{x} as C{int}. 

572 

573 @return: -1, 0 or +1 (C{int}). 

574 ''' 

575 try: 

576 s = x.signOf() # Fsum instance? 

577 except AttributeError: 

578 s = _signOf(x, 0) 

579 return s 

580 

581 

582def _sizeof(inst): 

583 '''(INTERNAL) Recursively size an C{inst}ance. 

584 

585 @return: Instance' size in bytes (C{int}), 

586 ignoring class attributes and 

587 counting duplicates only once or 

588 C{None}. 

589 

590 @note: With C{PyPy}, the size is always C{None}. 

591 ''' 

592 try: 

593 _zB = _sys.getsizeof 

594 _zD = _zB(None) # get some default 

595 except TypeError: # PyPy3.10 

596 return None 

597 

598 def _zR(s, iterable): 

599 z, _s = 0, s.add 

600 for o in iterable: 

601 i = id(o) 

602 if i not in s: 

603 _s(i) 

604 z += _zB(o, _zD) 

605 if isinstance(o, dict): 

606 z += _zR(s, o.keys()) 

607 z += _zR(s, o.values()) 

608 elif isinstance(o, _list_tuple_set_types): 

609 z += _zR(s, o) 

610 else: 

611 try: # size instance' attr values only 

612 z += _zR(s, o.__dict__.values()) 

613 except AttributeError: # None, int, etc. 

614 pass 

615 return z 

616 

617 return _zR(set(), (inst,)) 

618 

619 

620def splice(iterable, n=2, **fill): 

621 '''Split an iterable into C{n} slices. 

622 

623 @arg iterable: Items to be spliced (C{list}, C{tuple}, ...). 

624 @kwarg n: Number of slices to generate (C{int}). 

625 @kwarg fill: Optional fill value for missing items. 

626 

627 @return: A generator for each of B{C{n}} slices, 

628 M{iterable[i::n] for i=0..n}. 

629 

630 @raise TypeError: Invalid B{C{n}}. 

631 

632 @note: Each generated slice is a C{tuple} or a C{list}, 

633 the latter only if the B{C{iterable}} is a C{list}. 

634 

635 @example: 

636 

637 >>> from pygeodesy import splice 

638 

639 >>> a, b = splice(range(10)) 

640 >>> a, b 

641 ((0, 2, 4, 6, 8), (1, 3, 5, 7, 9)) 

642 

643 >>> a, b, c = splice(range(10), n=3) 

644 >>> a, b, c 

645 ((0, 3, 6, 9), (1, 4, 7), (2, 5, 8)) 

646 

647 >>> a, b, c = splice(range(10), n=3, fill=-1) 

648 >>> a, b, c 

649 ((0, 3, 6, 9), (1, 4, 7, -1), (2, 5, 8, -1)) 

650 

651 >>> tuple(splice(list(range(9)), n=5)) 

652 ([0, 5], [1, 6], [2, 7], [3, 8], [4]) 

653 

654 >>> splice(range(9), n=1) 

655 <generator object splice at 0x0...> 

656 ''' 

657 if not isint(n): 

658 raise _TypeError(n=n) 

659 

660 t = iterable 

661 if not isinstance(t, _list_tuple_types): 

662 t = tuple(t) # force tuple, also for PyPy3 

663 

664 if n > 1: 

665 if fill: 

666 fill = _xkwds_get(fill, fill=MISSING) 

667 if fill is not MISSING: 

668 m = len(t) % n 

669 if m > 0: # same type fill 

670 t += type(t)((fill,) * (n - m)) 

671 for i in range(n): 

672 # XXX t[i::n] chokes PyChecker 

673 yield t[slice(i, None, n)] 

674 else: 

675 yield t 

676 

677 

678def _splituple(strs, *sep_splits): # in .mgrs, .osgr, .webmercator 

679 '''(INTERNAL) Split a C{comma}- or C{whitespace}-separated 

680 string into a C{tuple} of stripped strings. 

681 ''' 

682 t = (strs.split(*sep_splits) if sep_splits else 

683 strs.replace(_COMMA_, _SPACE_).split()) if strs else () 

684 return tuple(s.strip() for s in t if s) 

685 

686 

687def unsigned0(x): 

688 '''Unsign if C{0.0}. 

689 

690 @return: C{B{x}} if B{C{x}} else C{0.0}. 

691 ''' 

692 return x if x else _0_0 

693 

694 

695def _xcopy(obj, deep=False): 

696 '''(INTERNAL) Copy an object, shallow or deep. 

697 

698 @arg obj: The object to copy (any C{type}). 

699 @kwarg deep: If C{True} make a deep, otherwise 

700 a shallow copy (C{bool}). 

701 

702 @return: The copy of B{C{obj}}. 

703 ''' 

704 return _deepcopy(obj) if deep else _copy(obj) 

705 

706 

707def _xdup(obj, deep=False, **items): 

708 '''(INTERNAL) Duplicate an object, replacing some attributes. 

709 

710 @arg obj: The object to copy (any C{type}). 

711 @kwarg deep: If C{True} copy deep, otherwise shallow. 

712 @kwarg items: Attributes to be changed (C{any}). 

713 

714 @return: A duplicate of B{C{obj}} with modified 

715 attributes, if any B{C{items}}. 

716 

717 @raise AttributeError: Some B{C{items}} invalid. 

718 ''' 

719 d = _xcopy(obj, deep=deep) 

720 for n, v in items.items(): 

721 if getattr(d, n, v) != v: 

722 setattr(d, n, v) 

723 elif not hasattr(d, n): 

724 t = _MODS.named.classname(obj) 

725 t = _SPACE_(_DOT_(t, n), _invalid_) 

726 raise _AttributeError(txt=t, obj=obj, **items) 

727# if items: 

728# _MODS.props._update_all(d) 

729 return d 

730 

731 

732def _xgeographiclib(where, *required): 

733 '''(INTERNAL) Import C{geographiclib} and check required version. 

734 ''' 

735 try: 

736 _xpackage(_xgeographiclib) 

737 import geographiclib 

738 except ImportError as x: 

739 raise _xImportError(x, where, Error=LazyImportError) 

740 return _xversion(geographiclib, where, *required) 

741 

742 

743def _xImportError(exc, where, Error=_ImportError, **name): 

744 '''(INTERNAL) Embellish an C{Lazy/ImportError}. 

745 ''' 

746 t = _req_d_by(where, **name) 

747 return Error(_Xstr(exc), txt=t, cause=exc) 

748 

749 

750def _xinstanceof(*Types, **names_values): 

751 '''(INTERNAL) Check C{Types} of all C{name=value} pairs. 

752 

753 @arg Types: One or more classes or types (C{class}), all 

754 positional. 

755 @kwarg names_values: One or more C{B{name}=value} pairs 

756 with the C{value} to be checked. 

757 

758 @raise TypeError: One B{C{names_values}} pair is not an 

759 instance of any of the B{C{Types}}. 

760 ''' 

761 if not (Types and names_values): 

762 raise _xAssertionError(_xinstanceof, *Types, **names_values) 

763 

764 for n, v in names_values.items(): 

765 if not isinstance(v, Types): 

766 raise _TypesError(n, v, *Types) 

767 

768 

769def _xisscalar(**names_values): 

770 '''(INTERNAL) Check all C{name=value} pairs to be C{scalar}. 

771 ''' 

772 for n, v in names_values.items(): 

773 if not isscalar(v): 

774 raise _TypeError(n, v, txt=_not_scalar_) 

775 

776 

777def _xnumpy(where, *required): 

778 '''(INTERNAL) Import C{numpy} and check required version. 

779 ''' 

780 try: 

781 _xpackage(_xnumpy) 

782 import numpy 

783 except ImportError as x: 

784 raise _xImportError(x, where) 

785 return _xversion(numpy, where, *required) 

786 

787 

788def _xor(x, *xs): 

789 '''(INTERNAL) Exclusive-or C{x} and C{xs}. 

790 ''' 

791 for x_ in xs: 

792 x ^= x_ 

793 return x 

794 

795 

796def _xpackage(_xpkg): 

797 '''(INTERNAL) Check dependency to be excluded. 

798 ''' 

799 n = _xpkg.__name__[2:] # remove _x 

800 if n in _XPACKAGES: 

801 x = _SPACE_(n, _in_, _PYGEODESY_XPACKAGES_) 

802 e = _enquote(_getenv(_PYGEODESY_XPACKAGES_, NN)) 

803 raise ImportError(_EQUAL_(x, e)) 

804 

805 

806def _xscipy(where, *required): 

807 '''(INTERNAL) Import C{scipy} and check required version. 

808 ''' 

809 try: 

810 _xpackage(_xscipy) 

811 import scipy 

812 except ImportError as x: 

813 raise _xImportError(x, where) 

814 return _xversion(scipy, where, *required) 

815 

816 

817def _xsubclassof(*Classes, **names_values): 

818 '''(INTERNAL) Check (super) class of all C{name=value} pairs. 

819 

820 @arg Classes: One or more classes or types (C{class}), all 

821 positional. 

822 @kwarg names_values: One or more C{B{name}=value} pairs 

823 with the C{value} to be checked. 

824 

825 @raise TypeError: One B{C{names_values}} pair is not a 

826 (sub-)class of any of the B{C{Classes}}. 

827 ''' 

828 if not (Classes and names_values): 

829 raise _xAssertionError(_xsubclassof, *Classes, **names_values) 

830 

831 for n, v in names_values.items(): 

832 if not issubclassof(v, *Classes): 

833 raise _TypesError(n, v, *Classes) 

834 

835 

836def _xversion(package, where, *required, **name): 

837 '''(INTERNAL) Check the C{package} version vs B{C{required}}. 

838 ''' 

839 if required: 

840 t = _version_info(package) 

841 if t[:len(required)] < required: 

842 t = _SPACE_(package.__name__, 

843 _version_, _DOT_(*t), 

844 _below_, _DOT_(*required), 

845 _req_d_by(where, **name)) 

846 raise ImportError(t) 

847 return package 

848 

849 

850def _xzip(*args, **strict): # PYCHOK no cover 

851 '''(INTERNAL) Standard C{zip(..., strict=True)}. 

852 ''' 

853 s = _xkwds_get(strict, strict=True) 

854 if s: 

855 if _zip is zip: # < (3, 10) 

856 t = _MODS.streprs.unstr(_xzip, *args, strict=s) 

857 raise _NotImplementedError(t, txt=None) 

858 return _zip(*args) 

859 return zip(*args) 

860 

861 

862if _sys_version_info2 < (3, 10): # see .errors 

863 _zip = zip # PYCHOK exported 

864else: # Python 3.10+ 

865 

866 def _zip(*args): 

867 return zip(*args, strict=True) 

868 

869_XPACKAGES = _splituple(_getenv(_PYGEODESY_XPACKAGES_, NN).lower()) 

870 

871# **) MIT License 

872# 

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

874# 

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

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

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

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

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

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

881# 

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

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

884# 

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

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

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

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

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

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

891# OTHER DEALINGS IN THE SOFTWARE.