1# http://pyrocko.org - GPLv3 

2# 

3# The Pyrocko Developers, 21st Century 

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

5 

6import logging 

7import numpy as num 

8import matplotlib.pyplot as plt 

9 

10from matplotlib.cm import ScalarMappable 

11from matplotlib.ticker import FuncFormatter 

12 

13from pyrocko.plot import beachball 

14from pyrocko.gf.meta import Timing 

15from pyrocko.gf import LocalEngine, Target, RectangularSource, map_anchor 

16from pyrocko.util import num_full_like 

17 

18 

19km = 1e3 

20r2d = 180. / num.pi 

21d2r = num.pi / 180. 

22 

23logger = logging.getLogger(__name__) 

24 

25 

26QUANTITY_LABEL = { 

27 'displacement': 'Displacement [m]', 

28 'velocity': 'Velocity [m/s]', 

29 'acceleration': 'Acceleration [m/s²]' 

30} 

31 

32 

33def get_azimuthal_targets( 

34 store_id, source, radius, 

35 azi_begin=0., azi_end=360., dazi=1., 

36 depth=0.0, 

37 interpolation='multilinear', 

38 components='RTZ', quantity='displacement'): 

39 

40 assert dazi > 0. 

41 assert azi_begin < azi_end 

42 

43 nstations = int((azi_end - azi_begin) // dazi) 

44 assert nstations > 0 

45 

46 azimuths = num.linspace(azi_begin, azi_end, nstations) 

47 

48 coords = num.zeros((2, nstations)) 

49 coords[0, :] = num.cos(azimuths*d2r) 

50 coords[1, :] = num.sin(azimuths*d2r) 

51 coords *= radius 

52 

53 dips = {'R': 0., 'T': 0., 'Z': -90.} 

54 for comp in components: 

55 assert comp in dips.keys() 

56 

57 target_kwargs = dict( 

58 quantity=quantity, 

59 interpolation=interpolation, 

60 store_id=store_id) 

61 

62 targets = [ 

63 Target( 

64 lat=source.lat, 

65 lon=source.lon, 

66 north_shift=coords[0, iazi] + source.north_shift, 

67 east_shift=coords[1, iazi] + source.east_shift, 

68 depth=depth, 

69 azimuth={ 

70 'R': azi, 

71 'T': azi+90., 

72 'Z': 0. 

73 }[channel], 

74 dip=dips[channel], 

75 codes=('', 'S%01d' % iazi, '', channel), 

76 **target_kwargs) 

77 for iazi, azi in enumerate(azimuths) 

78 for channel in components] 

79 

80 for target, azi in zip(targets, azimuths): 

81 target.azimuth = azi 

82 target.dazi = dazi 

83 

84 return targets, azimuths 

85 

86 

87def get_seismogram_array( 

88 response, fmin=None, fmax=None, 

89 component='R', envelope=False): 

90 resp = response 

91 assert len(resp.request.sources) == 1, 'more than one source in response' 

92 

93 tmin = None 

94 tmax = None 

95 traces = [] 

96 

97 for _, target, tr in response.iter_results(): 

98 if target.codes[-1] != component: 

99 continue 

100 assert hasattr(target, 'azimuth') 

101 assert target.dazi 

102 

103 if fmin is not None: 

104 tr.highpass(4, fmin, demean=False) 

105 

106 if fmax is not None: 

107 tr.lowpass(4, fmax, demean=False) 

108 

109 tmin = min(tmin, tr.tmin) if tmin else tr.tmin 

110 tmax = max(tmax, tr.tmax) if tmax else tr.tmax 

111 traces.append(tr) 

112 

113 for tr in traces: 

114 tr.extend(tmin, tmax, fillmethod='repeat') 

115 if envelope: 

116 tr.abshilbert() 

117 

118 data = num.array([tr.get_ydata() for tr in traces]) 

119 nsamples = data.shape[1] 

120 return data, num.linspace(tmin, tmax, nsamples) 

121 

122 

123def hillshade(array, azimuth, angle_altitude): 

124 azimuth = 360.0 - azimuth 

125 azi = azimuth * r2d 

126 alt = angle_altitude * r2d 

127 

128 x, y = num.gradient(array) 

129 slope = num.pi/2. - num.arctan(num.sqrt(x*x + y*y)) 

130 aspect = num.arctan2(-x, y) 

131 

132 shaded = num.sin(alt)*num.sin(slope) \ 

133 + num.cos(alt)*num.cos(slope)*num.cos((azi - num.pi/2.) - aspect) 

134 

135 return (shaded + 1.)/2. 

136 

137 

138def hillshade_seismogram_array( 

139 seismogram_array, rgba_map, 

140 shad_lim=(.4, .98), contrast=1., blend_mode='multiply'): 

141 assert blend_mode in ('multiply', 'screen'), 'unknown blend mode' 

142 assert shad_lim[0] < shad_lim[1], 'bad shading limits' 

143 from scipy.ndimage import convolve as im_conv 

144 # Light source from somewhere above - psychologically the best choice 

145 # from upper left 

146 ramp = num.array([[1., 0.], [0., -1.]]) * contrast 

147 

148 # convolution of two 2D arrays 

149 shad = im_conv(seismogram_array, ramp.T).ravel() 

150 shad *= -1. 

151 

152 # if there are strong artifical edges in the data, shades get 

153 # dominated by them. Cutting off the largest and smallest 2% of 

154 # # shades helps 

155 percentile2 = num.percentile(shad, 2.0) 

156 percentile98 = num.percentile(shad, 98.0) 

157 

158 shad[shad > percentile98] = percentile98 

159 shad[shad < percentile2] = percentile2 

160 

161 # # normalize shading 

162 shad -= num.nanmin(shad) 

163 shad /= num.nanmax(shad) 

164 

165 # # reduce range to balance gray color 

166 shad *= shad_lim[1] - shad_lim[0] 

167 shad += shad_lim[0] 

168 

169 if blend_mode == 'screen': 

170 rgba_map[:, :3] = 1. - ((1. - rgba_map[:, :3])*(shad[:, num.newaxis])) 

171 elif blend_mode == 'multiply': 

172 rgba_map[:, :3] *= shad[:, num.newaxis] 

173 

174 return rgba_map 

175 

176 

177def plot_directivity( 

178 engine, source, store_id, 

179 distance=300*km, azi_begin=0., azi_end=360., dazi=1., 

180 phases={'P': 'first{stored:any_P}-10%', 

181 'S': 'last{stored:any_S}+50'}, 

182 interpolation='multilinear', 

183 target_depth=0.0, 

184 quantity='displacement', envelope=False, 

185 component='R', fmin=0.01, fmax=0.1, 

186 hillshade=True, cmap=None, 

187 plot_mt='full', show_phases=True, show_description=True, 

188 reverse_time=False, show_nucleations=True, axes=None, nthreads=0): 

189 ''' 

190 Plot the directivity and radiation characteristics of source models. 

191 

192 Synthetic seismic traces (R, T or Z) are forward-modelled at a defined 

193 radius, covering the full or partial azimuthal range and projected on a 

194 polar plot. Difference in the amplitude are enhanced by hillshading 

195 the data. 

196 

197 :param engine: Forward modelling engine 

198 :type engine: :py:class:`~pyrocko.gf.seismosizer.Engine` 

199 :param source: Parametrized source model 

200 :type source: :py:class:`~pyrocko.gf.seismosizer.Source` 

201 :param store_id: Store ID used for forward modelling 

202 :type store_id: str 

203 :param distance: Distance in [m] 

204 :type distance: float 

205 :param azi_begin: Begin azimuth in [deg] 

206 :type azi_begin: float 

207 :param azi_end: End azimuth in [deg] 

208 :type azi_end: float 

209 :param dazi: Delta azimuth, bin size [deg] 

210 :type dazi: float 

211 :param phase_begin: Start time of the window 

212 :type phase_begin: :py:class:`~pyrocko.gf.meta.Timing` 

213 :param phase_end: End time of the window 

214 :type phase_end: :py:class:`~pyrocko.gf.meta.Timing` 

215 :param target_depth: Receiver depth [m] 

216 :type target_depth: float 

217 :param quantity: Seismogram quantity, default ``displacement`` 

218 :type quantity: str 

219 :param envelope: Plot envelope instead of seismic trace 

220 :type envelope: bool 

221 :param component: Forward modelled component, default ``R``. Choose from 

222 `RTZ` 

223 :type component: str 

224 :param fmin: Bandpass lower frequency [Hz], default ``0.01`` 

225 :type fmin: float 

226 :param fmax: Bandpass upper frequency [Hz], default ``0.1`` 

227 :type fmax: float 

228 :param hillshade: Enable hillshading, default ``True`` 

229 :type hillshade: bool 

230 :param cmap: Matplotlib colormap to use, default ``seismic``. 

231 When ``envelope`` is ``True`` the default colormap will be ``Reds``. 

232 :type cmap: str 

233 :param plot_mt: Plot a centered moment tensor, default ``full``. 

234 Choose from ``full, deviatoric, dc or False`` 

235 :type plot_mt: str, bool 

236 :param show_phases: Show annotations, default ``True`` 

237 :type show_phases: bool 

238 :param show_description: Show description, default ``True`` 

239 :type show_description: bool 

240 :param reverse_time: Reverse time axis. First phases arrive at the center, 

241 default ``False`` 

242 :type reverse_time: bool 

243 :param show_nucleations: Show nucleation piercing points on the moment 

244 tensor, default ``True`` 

245 :type show_nucleations: bool 

246 :param axes: Give axes to plot into 

247 :type axes: :py:class:`matplotlib.axes.Axes` 

248 :param nthreads: Number of threads used for forward modelling, 

249 default ``0`` - all available cores 

250 :type nthreads: int 

251 ''' 

252 

253 if axes is None: 

254 fig = plt.figure() 

255 ax = fig.add_subplot(111, polar=True) 

256 else: 

257 fig = axes.figure 

258 ax = axes 

259 

260 if envelope and cmap is None: 

261 cmap = 'Reds' 

262 elif cmap is None: 

263 cmap = 'seismic' 

264 

265 targets, azimuths = get_azimuthal_targets( 

266 store_id, source, distance, azi_begin, azi_end, dazi, 

267 depth=target_depth, 

268 interpolation=interpolation, 

269 components='R', quantity=quantity) 

270 ref_target = targets[0] 

271 store = engine.get_store(store_id) 

272 mt = source.pyrocko_moment_tensor(store=store, target=ref_target) 

273 

274 resp = engine.process(source, targets, nthreads=nthreads) 

275 data, times = get_seismogram_array( 

276 resp, fmin, fmax, 

277 component=component, envelope=envelope) 

278 

279 nucl_depth = source.depth 

280 nucl_distance = distance 

281 

282 if hasattr(source, 'nucleation_x') and hasattr(source, 'nucleation_y'): 

283 try: 

284 iter(source.nucleation_x) 

285 nx = float(source.nucleation_x[0]) 

286 ny = float(source.nucleation_y[0]) 

287 

288 except TypeError: 

289 nx = source.nucleation_x 

290 ny = source.nucleation_y 

291 

292 nucl_distance += nx * source.length/2. 

293 nucl_depth += ny*num.sin(source.dip*d2r) * source.width/2. 

294 

295 if hasattr(source, 'anchor'): 

296 anch_x, anch_y = map_anchor[source.anchor] 

297 nucl_distance -= anch_x * source.length/2. 

298 nucl_depth -= anch_y*num.sin(source.dip*d2r) * source.width/2. 

299 

300 timings = [Timing(p) for p in phases.values()] 

301 phase_times = [store.t(t, source, ref_target) for t in timings] 

302 

303 tbegin = min(phase_times) 

304 tend = max(phase_times) 

305 tsel = num.logical_and(times >= tbegin, times <= tend) 

306 

307 data = data[:, tsel].T 

308 times = times[tsel] 

309 duration = times[-1] - times[0] 

310 

311 vmax = num.abs(data).max() 

312 cmw = ScalarMappable(cmap=cmap) 

313 cmw.set_array(data) 

314 cmw.set_clim(-vmax, vmax) 

315 

316 if envelope: 

317 cmw.set_clim(0., vmax) 

318 

319 ax.set_theta_zero_location('N') 

320 ax.set_theta_direction(-1) 

321 

322 strike_label = mt.strike1 

323 if hasattr(source, 'strike'): 

324 strike_label = source.strike 

325 

326 try: 

327 ax.set_rlabel_position(strike_label % 180.) 

328 except AttributeError: 

329 logger.warn('Old matplotlib version: cannot set label positions') 

330 

331 def r_fmt(v, p): 

332 if v < tbegin or v > tend: 

333 return '' 

334 return '%g s' % v 

335 

336 ax.yaxis.set_major_formatter(FuncFormatter(r_fmt)) 

337 if reverse_time: 

338 ax.set_rlim(times[0] - .3*duration, times[-1]) 

339 else: 

340 ax.set_rlim(times[-1] + .3*duration, times[0]) 

341 

342 ax.grid(zorder=20) 

343 

344 if isinstance(plot_mt, str): 

345 mt_size = .15 

346 beachball.plot_beachball_mpl( 

347 mt, ax, 

348 beachball_type=plot_mt, size=mt_size, 

349 size_units='axes', color_t=(0.7, 0.4, 0.4), 

350 position=(.5, .5), linewidth=1.) 

351 

352 if hasattr(source, 'nucleation_x') and hasattr(source, 'nucleation_y')\ 

353 and show_nucleations: 

354 try: 

355 iter(source.nucleation_x) 

356 nucleation_x = source.nucleation_x 

357 nucleation_y = source.nucleation_y 

358 except TypeError: 

359 nucleation_x = [source.nucleation_x] 

360 nucleation_y = [source.nucleation_y] 

361 

362 for nx, ny in zip(nucleation_x, nucleation_y): 

363 angle = float(num.arctan2(ny, nx)) 

364 rtp = num.array([[1., angle, (90.-source.strike)*d2r]]) 

365 points = beachball.numpy_rtp2xyz(rtp) 

366 x, y = beachball.project(points, projection='lambert').T 

367 norm = num.sqrt(x**2 + y**2) 

368 x = x / norm * mt_size/2. 

369 y = y / norm * mt_size/2. 

370 ax.plot(x+.5, y+.5, 'x', ms=6, mew=2, mec='darkred', mfc='red', 

371 transform=ax.transAxes, zorder=10) 

372 

373 mesh = ax.pcolormesh( 

374 azimuths * d2r, times, data, 

375 cmap=cmw.cmap, norm=cmw.norm, shading='gouraud', zorder=0) 

376 

377 if hillshade: 

378 mesh.update_scalarmappable() 

379 color = mesh.get_facecolor() 

380 color = hillshade_seismogram_array( 

381 data, color, shad_lim=(.85, 1.), blend_mode='multiply') 

382 mesh.set_facecolor(color) 

383 

384 if show_phases: 

385 label_theta = 270. 

386 theta = num.linspace(0, 2*num.pi, 360) 

387 

388 for label, phase_str in phases.items(): 

389 phase = Timing(phase_str) 

390 

391 phase.offset = 0. 

392 phase.offset_is_slowness = False 

393 phase.offset_is_percent = False 

394 

395 time = store.t(phase, source, ref_target) 

396 times = num_full_like(theta, time) 

397 

398 ax.plot(theta, times, color='k', alpha=.3, lw=1., ls='--') 

399 

400 ax.text( 

401 label_theta*d2r, time, label, 

402 ha='left', color='k', fontsize='small') 

403 label_theta += 30. 

404 

405 if show_description: 

406 description = ( 

407 'Component {component:s}\n' 

408 'Distance {distance:g} km').format( 

409 component=component, distance=distance / km) 

410 

411 if fmin and fmax: 

412 description += '\nBandpass {fmin:g} - {fmax:g} Hz'.format( 

413 fmin=fmin, fmax=fmax) 

414 elif fmin: 

415 description += '\nHighpass {fmin:g} Hz'.format(fmin=fmin) 

416 elif fmax: 

417 description += '\nLowpass {fmax:g} Hz'.format(fmax=fmax) 

418 ax.text( 

419 -.05, -.05, description, 

420 fontsize='small', 

421 ha='left', va='bottom', transform=ax.transAxes) 

422 

423 cbar_label = QUANTITY_LABEL[quantity] 

424 if envelope: 

425 cbar_label = 'Envelope ' + cbar_label 

426 

427 cb = fig.colorbar( 

428 cmw, ax=ax, 

429 orientation='vertical', shrink=.8, pad=0.11) 

430 

431 cb.set_label(cbar_label) 

432 

433 if axes is None: 

434 plt.show() 

435 return resp 

436 

437 

438__all__ = ['plot_directivity'] 

439 

440 

441if __name__ == '__main__': 

442 engine = LocalEngine(store_superdirs=['.'], use_config=True) 

443 

444 rect_source = RectangularSource( 

445 depth=2.6*km, 

446 strike=240., 

447 dip=76.6, 

448 rake=-.4, 

449 anchor='top', 

450 

451 nucleation_x=-.57, 

452 nucleation_y=-.59, 

453 velocity=2070., 

454 

455 length=27*km, 

456 width=9.4*km, 

457 slip=1.4) 

458 

459 resp = plot_directivity( 

460 engine, rect_source, 'crust2_ib', 

461 dazi=5, component='R', quantity='displacement', envelope=True)