1# http://pyrocko.org - GPLv3 

2# 

3# The Pyrocko Developers, 21st Century 

4# ---|P------/S----------~Lg---------- 

5 

6import logging 

7import math 

8import numpy as num 

9from collections import OrderedDict 

10 

11import pyrocko.orthodrome as od 

12 

13from pyrocko.guts import (Object, Float, String, List, StringChoice, 

14 DateTimestamp) 

15from pyrocko.model import Location 

16 

17guts_prefix = 'pf.gnss' 

18logger = logging.getLogger('pyrocko.model.gnss') 

19 

20 

21class GNSSComponent(Object): 

22 ''' 

23 Component of a GNSSStation 

24 ''' 

25 unit = StringChoice.T( 

26 choices=['mm', 'cm', 'm'], 

27 help='Unit of displacement', 

28 default='m') 

29 

30 shift = Float.T( 

31 default=0., 

32 help="Component's shift in unit") 

33 

34 sigma = Float.T( 

35 default=0., 

36 help='One sigma uncertainty of the measurement') 

37 

38 def __add__(self, other): 

39 if not isinstance(other, self.__class__): 

40 raise AttributeError('Other has to be of instance %s' 

41 % self.__class__) 

42 comp = self.__class__() 

43 comp.shift = self.shift + other.shift 

44 comp.sigma = math.sqrt(self.sigma**2 + other.sigma**2) 

45 return comp 

46 

47 def __iadd__(self, other): 

48 self.shift += other.shift 

49 self.sigma = math.sqrt(self.sigma**2 + other.sigma**2) 

50 return self 

51 

52 

53class GNSSStation(Location): 

54 ''' 

55 Representation of a GNSS station during a campaign measurement 

56 

57 For more information see 

58 http://kb.unavco.org/kb/assets/660/UNAVCO_Campaign_GPS_GNSS_Handbook.pdf 

59 ''' 

60 

61 code = String.T( 

62 help='Four letter station code', 

63 optional=True) 

64 

65 style = StringChoice.T( 

66 choices=['static', 'rapid_static', 'kinematic'], 

67 default='static') 

68 

69 survey_start = DateTimestamp.T( 

70 optional=True, 

71 help='Survey start time') 

72 

73 survey_end = DateTimestamp.T( 

74 optional=True, 

75 help='Survey end time') 

76 

77 correlation_ne = Float.T( 

78 default=0., 

79 help='North-East component correlation') 

80 

81 correlation_eu = Float.T( 

82 default=0., 

83 help='East-Up component correlation') 

84 

85 correlation_nu = Float.T( 

86 default=0., 

87 help='North-Up component correlation') 

88 

89 north = GNSSComponent.T( 

90 optional=True) 

91 

92 east = GNSSComponent.T( 

93 optional=True) 

94 

95 up = GNSSComponent.T( 

96 optional=True) 

97 

98 def __eq__(self, other): 

99 try: 

100 return self.code == other.code 

101 except AttributeError: 

102 return False 

103 

104 def get_covariance_matrix(self): 

105 components = self.components.values() 

106 ncomponents = self.ncomponents 

107 

108 covar = num.zeros((ncomponents, ncomponents)) 

109 for ic1, comp1 in enumerate(components): 

110 for ic2, comp2 in enumerate(components): 

111 corr = self._get_comp_correlation(comp1, comp2) 

112 covar[ic1, ic2] = corr * comp1.sigma * comp2.sigma 

113 

114 # This floating point operation is inaccurate: 

115 # corr * comp1.sigma * comp2.sigma != corr * comp2.sigma * comp1.sigma 

116 # 

117 # Hence this identity 

118 covar[num.tril_indices_from(covar, k=-1)] = \ 

119 covar[num.triu_indices_from(covar, k=1)] 

120 

121 return covar 

122 

123 def get_correlation_matrix(self): 

124 components = self.components.values() 

125 ncomponents = self.ncomponents 

126 

127 corr = num.zeros((ncomponents, ncomponents)) 

128 corr[num.diag_indices_from(corr)] = num.array( 

129 [c.sigma for c in components]) 

130 

131 for ic1, comp1 in enumerate(components): 

132 for ic2, comp2 in enumerate(components): 

133 if comp1 is comp2: 

134 continue 

135 corr[ic1, ic2] = self._get_comp_correlation(comp1, comp2) 

136 

137 # See comment at get_covariance_matrix 

138 corr[num.tril_indices_from(corr, k=-1)] = \ 

139 corr[num.triu_indices_from(corr, k=1)] 

140 

141 return corr 

142 

143 def get_displacement_data(self): 

144 return num.array([c.shift for c in self.components.values()]) 

145 

146 def get_component_mask(self): 

147 return num.array( 

148 [False if self.__getattribute__(name) is None else True 

149 for name in ('north', 'east', 'up')], dtype=bool) 

150 

151 @property 

152 def components(self): 

153 return OrderedDict( 

154 [(name, self.__getattribute__(name)) 

155 for name in ('north', 'east', 'up') 

156 if self.__getattribute__(name) is not None]) 

157 

158 @property 

159 def ncomponents(self): 

160 return len(self.components) 

161 

162 def _get_comp_correlation(self, comp1, comp2): 

163 if comp1 is comp2: 

164 return 1. 

165 

166 s = self 

167 

168 correlation_map = { 

169 (s.north, s.east): s.correlation_ne, 

170 (s.east, s.up): s.correlation_eu, 

171 (s.north, s.up): s.correlation_nu 

172 } 

173 

174 return correlation_map.get( 

175 (comp1, comp2), 

176 correlation_map.get((comp2, comp1), False)) 

177 

178 

179class GNSSCampaign(Object): 

180 

181 stations = List.T( 

182 GNSSStation.T(), 

183 help='List of GNSS campaign measurements') 

184 

185 name = String.T( 

186 help='Campaign name', 

187 default='Unnamed campaign') 

188 

189 survey_start = DateTimestamp.T( 

190 optional=True) 

191 

192 survey_end = DateTimestamp.T( 

193 optional=True) 

194 

195 def __init__(self, *args, **kwargs): 

196 Object.__init__(self, *args, **kwargs) 

197 self._cov_mat = None 

198 self._cor_mat = None 

199 

200 def add_station(self, station): 

201 self._cor_mat = None 

202 self._cov_mat = None 

203 return self.stations.append(station) 

204 

205 def remove_station(self, station_code): 

206 try: 

207 station = self.get_station(station_code) 

208 self.stations.remove(station) 

209 self._cor_mat = None 

210 self._cov_mat = None 

211 except ValueError: 

212 logger.warning('Station {} does not exist in campaign, ' 

213 'do nothing.'.format(station_code)) 

214 

215 def get_station(self, station_code): 

216 for sta in self.stations: 

217 if sta.code == station_code: 

218 return sta 

219 raise ValueError('Could not find station %s' % station_code) 

220 

221 def get_center_latlon(self): 

222 return od.geographic_midpoint_locations(self.stations) 

223 

224 def get_radius(self): 

225 coords = self.coordinates 

226 return od.distance_accurate50m( 

227 coords[:, 0].min(), coords[:, 1].min(), 

228 coords[:, 0].max(), coords[:, 1].max()) / 2. 

229 

230 def get_covariance_matrix(self): 

231 if self._cov_mat is None: 

232 ncomponents = self.ncomponents 

233 cov_arr = num.zeros((ncomponents, ncomponents)) 

234 

235 idx = 0 

236 for ista, sta in enumerate(self.stations): 

237 ncomp = sta.ncomponents 

238 cov_arr[idx:idx+ncomp, idx:idx+ncomp] = \ 

239 sta.get_covariance_matrix() 

240 idx += ncomp 

241 

242 self._cov_mat = cov_arr 

243 return self._cov_mat 

244 

245 def get_correlation_matrix(self): 

246 if self._cor_mat is None: 

247 ncomponents = self.ncomponents 

248 cor_arr = num.zeros((ncomponents, ncomponents)) 

249 

250 idx = 0 

251 for ista, sta in enumerate(self.stations): 

252 ncomp = sta.ncomponents 

253 cor_arr[idx:idx+ncomp, idx:idx+ncomp] = \ 

254 sta.get_correlation_matrix() 

255 idx += ncomp 

256 

257 self._cor_mat = cor_arr 

258 return self._cor_mat 

259 

260 def get_component_mask(self): 

261 return num.concatenate( 

262 [s.get_component_mask() for s in self.stations]) 

263 

264 def dump(self, *args, **kwargs): 

265 self.regularize() 

266 return Object.dump(self, *args, **kwargs) 

267 

268 @property 

269 def coordinates(self): 

270 return num.array([loc.effective_latlon for loc in self.stations]) 

271 

272 @property 

273 def nstations(self): 

274 return len(self.stations) 

275 

276 @property 

277 def ncomponents(self): 

278 return sum([s.ncomponents for s in self.stations])