# Coverage for pygeodesy/gars.py : 95%

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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 | # -*- coding: utf-8 -*- u'''Classes L{Garef} and L{GARSError} and several functions to encode, decode and inspect I{Global Area Reference System (GARS)} references. Transcribed from C++ class U{GARS <https://GeographicLib.SourceForge.io/html/classGeographicLib_1_1GARS.html>} by I{Charles Karney}. See also U{Global Area Reference System <https://WikiPedia.org/wiki/Global_Area_Reference_System>} and U{NGA (GARS) <https://Earth-Info.NGA.mil/GandG/coordsys/grids/gars.html>}. @newfield example: Example, Examples ''' from pygeodesy.dms import parse3llh, parseDMS2 from pygeodesy.fmath import EPS1_2 # _IsNotError from pygeodesy.lazily import _ALL_LAZY from pygeodesy.named import LatLon2Tuple, LatLonPrec3Tuple, \ _NamedStr, nameof, _xnamed from pygeodesy.utily import property_RO, _Strs # all public contants, classes and functions __all__ = _ALL_LAZY.gars + ('decode3', # functions 'encode', 'precision', 'resolution') __version__ = '20.01.22' _Digits = '0123456789' _LatLen = 2 _LatOrig = -90 _Letters = 'ABCDEFGHJKLMNPQRSTUVWXYZ' _LonLen = 3 _LonOrig = -180 _MaxPrec = 2 _MinLen = _LonLen + _LatLen _MaxLen = _MinLen + _MaxPrec _M1 = 2 _M2 = 2 _M3 = 3 _M = _M1 * _M2 * _M3 _LatOrig_M = _LatOrig * _M _LonOrig_M = _LonOrig * _M _LatOrig_M1 = _LatOrig * _M1 _LonOrig_M1_1 = _LonOrig * _M1 - 1 _Resolutions = tuple(1.0 / _ for _ in (_M1, _M1 * _M2, _M)) def _2divmod2(ll, Orig_M): x = ll * _M i = int(x) if i > x: # floor(x) i -= 1 x = i - Orig_M i = (x * _M1) // _M x -= i * _M // _M1 return i, x def _2fll(lat, lon, *unused): '''(INTERNAL) Convert lat, lon. ''' return parseDMS2(lat, lon) # def _2Garef(garef): # '''(INTERNAL) Check or create a L{Garef} instance. # ''' # if not isinstance(garef, Garef): # try: # garef = Garef(garef) # except (TypeError, ValueError): # raise _IsNotError(Garef.__name__, str.__name__, 'LatLon', garef=garef) # return garef def _2garstr2(garef): '''(INTERNAL) Check a garef string. ''' try: n, garstr = len(garef), garef.upper() if n < _MinLen or n > _MaxLen \ or garstr[:3] == 'INV' \ or not garstr.isalnum(): raise ValueError except (AttributeError, TypeError, ValueError): raise GARSError('%s: %r[%s]' % (Garef.__name__, garef, len(garef))) return garstr, n - _MinLen class GARSError(ValueError): '''Global Area Reference System (GARS) encode, decode or other L{Garef} issue. ''' pass class Garef(_NamedStr): '''Garef class, a C{_NamedStr}. ''' _latlon = None # cached latlon property _precision = None # no str.__init__ in Python 3 def __new__(cls, cll, precision=1, name=''): '''New L{Garef} from an other L{Garef} instance or garef C{str} or from a C{LatLon} instance or lat-/longitude C{str}. @param cll: Cell or location (L{Garef} or C{str}, C{LatLon} or C{str}). @keyword precision: Optional, the desired garef resolution and length (C{int} 0..2), see function L{gars.encode} for more details. @keyword name: Optional name (C{str}). @return: New L{Garef}. @raise RangeError: Invalid B{C{cll}} lat- or longitude. @raise TypeError: Invalid B{C{cll}}. @raise GARSError: INValid or non-alphanumeric B{C{cll}}. ''' if isinstance(cll, Garef): g, p = _2garstr2(str(cll)) self = str.__new__(cls, g) self._latlon = LatLon2Tuple(*cll._latlon) self._name = cll._name self._precision = p # cll._precision elif isinstance(cll, _Strs): if ',' in cll: lat, lon = _2fll(*parse3llh(cll)) cll = encode(lat, lon, precision=precision) # PYCHOK false self = str.__new__(cls, cll) self._latlon = LatLon2Tuple(lat, lon) self._precision = precision else: self = str.__new__(cls, cll.upper()) self._decode() else: # assume LatLon try: lat, lon = _2fll(cll.lat, cll.lon) except AttributeError: raise TypeError('%s: %r' % (Garef.__name__, cll)) cll = encode(lat, lon, precision=precision) # PYCHOK false self = str.__new__(cls, cll) self._latlon = LatLon2Tuple(lat, lon) self._precision = precision if name: self.name = name return self def _decode(self): # cache all decoded attrs lat, lon, p = decode3(self) if self._latlon is None: self._latlon = LatLon2Tuple(lat, lon) if self._precision is None: self._precision = p @property_RO def latlon(self): '''Get this garef's (center) lat- and longitude (L{LatLon2Tuple}). ''' if self._latlon is None: self._decode() return self._latlon @property_RO def precision(self): '''Get this garef's precision (C{int}). ''' if self._precision is None: self._decode() return self._precision def toLatLon(self, LatLon, **kwds): '''Return (the center of) this garef cell as an instance of the supplied C{LatLon} class. @param LatLon: Class to use (C{LatLon}). @keyword kwds: Optional keyword arguments for B{C{LatLon}}. @return: This garef location (B{C{LatLon}}). @raise GARSError: Invalid B{C{LatLon}}. ''' if LatLon is None: raise GARSError('%s invalid: %r' % ('LatLon', LatLon)) return self._xnamed(LatLon(*self.latlon, **kwds)) def decode3(garef, center=True): '''Decode a C{garef} to lat-, longitude and precision. @param garef: To be decoded (L{Garef} or C{str}). @keyword center: If C{True} the center, otherwise the south-west, lower-left corner (C{bool}). @return: A L{LatLonPrec3Tuple}C{(lat, lon, precision)}. @raise GARSError: Invalid B{C{garef}}, INValid, non-alphanumeric or bad length B{C{garef}}. ''' def _Error(i): return GARSError('%s invalid: %r[%s]' % ('garef', garef, i)) def _ll(chars, g, i, j, lo, hi): ll, b = 0, len(chars) for i in range(i, j): d = chars.find(g[i]) if d < 0: raise _Error(i) ll = ll * b + d if ll < lo or ll > hi: raise _Error(j) return ll def _ll2(lon, lat, g, i, m): d = _Digits.find(g[i]) if d < 1 or d > m * m: raise _Error(i) d, r = divmod(d - 1, m) lon = lon * m + r lat = lat * m + (m - 1 - d) return lon, lat g, precision = _2garstr2(garef) lon = _ll(_Digits, g, 0, _LonLen, 1, 720) + _LonOrig_M1_1 lat = _ll(_Letters, g, _LonLen, _MinLen, 0, 359) + _LatOrig_M1 if precision > 0: lon, lat = _ll2(lon, lat, g, _MinLen, _M2) if precision > 1: lon, lat = _ll2(lon, lat, g, _MinLen + 1, _M3) r = _Resolutions[precision] # == 1.0 / unit if center: lon = lon * 2 + 1 lat = lat * 2 + 1 r *= 0.5 lon *= r lat *= r return _xnamed(LatLonPrec3Tuple(lat, lon, precision), nameof(garef)) def encode(lat, lon, precision=1): # MCCABE 14 '''Encode a lat-/longitude as a C{garef} of the given precision. @param lat: Latitude (C{degrees}). @param lon: Longitude (C{degrees}). @keyword precision: Optional, the desired C{garef} resolution and length (C{int} 0..2). @return: The C{garef} (C{str}). @raise RangeError: Invalid B{C{lat}} or B{C{lon}}. @raise GARSError: Invalid B{C{precision}}. @note: The C{garef} length is M{precision + 5} and the C{garef} resolution is B{30′} for B{C{precision}} 0, B{15′} for 1 and B{5′} for 2, respectively. ''' def _digit(x, y, m): return _Digits[m * (m - y - 1) + x + 1], def _str(chars, x, n): s, b = [], len(chars) for i in range(n): x, i = divmod(x, b) s.append(chars[i]) return tuple(reversed(s)) try: p = int(precision) if p < 0 or p > _MaxPrec: raise ValueError except (TypeError, ValueError): raise GARSError('%s invalid: %r' % ('precision', precision)) lat, lon = _2fll(lat, lon) if lat == 90: lat *= EPS1_2 ix, x = _2divmod2(lon, _LonOrig_M) iy, y = _2divmod2(lat, _LatOrig_M) g = _str(_Digits, ix + 1, _LonLen) + _str(_Letters, iy, _LatLen) if p > 0: ix, x = divmod(x, _M3) iy, y = divmod(y, _M3) g += _digit(ix, iy, _M2) if p > 1: g += _digit(x, y, _M3) return ''.join(g) def precision(res): '''Determine the L{Garef} precision to meet a required (geographic) resolution. @param res: The required resolution (C{degrees}). @return: The L{Garef} precision (C{int} 0..2). @see: Function L{gars.encode} for more C{precision} details. ''' r = abs(res) for p in range(_MaxPrec): if resolution(p) <= r: return p return _MaxPrec def resolution(prec): '''Determine the (geographic) resolution of a given L{Garef} precision. @param prec: The given precision (C{int}). @return: The (geographic) resolution (C{degrees}). @see: Function L{gars.encode} for more C{precision} details. ''' return _Resolutions[max(0, min(prec, _MaxPrec))] # **) MIT License # # Copyright (C) 2016-2020 -- mrJean1 at Gmail -- All Rights Reserved. # # Permission is hereby granted, free of charge, to any person obtaining a # copy of this software and associated documentation files (the "Software"), # to deal in the Software without restriction, including without limitation # the rights to use, copy, modify, merge, publish, distribute, sublicense, # and/or sell copies of the Software, and to permit persons to whom the # Software is furnished to do so, subject to the following conditions: # # The above copyright notice and this permission notice shall be included # in all copies or substantial portions of the Software. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS # OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL # THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR # OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, # ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR # OTHER DEALINGS IN THE SOFTWARE.