def test_basic_inversion(self): """ Test to see if inversion recovers model """ h = [(2, 30)] meshObj = Mesh.TensorMesh((h, h, [(2, 10)]), x0='CCN') mod = 0.00025 * np.ones(meshObj.nC) mod[(meshObj.gridCC[:, 0] > -4.) & (meshObj.gridCC[:, 1] > -4.) & (meshObj.gridCC[:, 0] < 4.) & (meshObj.gridCC[:, 1] < 4.)] = 0.001 times = np.logspace(-4, -2, 5) waveObj = VRM.WaveformVRM.SquarePulse(0.02) x, y = np.meshgrid(np.linspace(-17, 17, 16), np.linspace(-17, 17, 16)) x, y, z = mkvc(x), mkvc(y), 0.5 * np.ones(np.size(x)) rxList = [VRM.Rx.Point(np.c_[x, y, z], times, 'dbdt', 'z')] txNodes = np.array([[-20, -20, 0.001], [20, -20, 0.001], [20, 20, 0.001], [-20, 20, 0.01], [-20, -20, 0.001]]) txList = [VRM.Src.LineCurrent(rxList, txNodes, 1., waveObj)] Survey = VRM.Survey(txList) Problem = VRM.Problem_Linear(meshObj, refFact=2) Problem.pair(Survey) Survey.makeSyntheticData(mod) Survey.eps = 1e-11 dmis = DataMisfit.l2_DataMisfit(Survey) W = mkvc((np.sum(np.array(Problem.A)**2, axis=0)))**0.25 reg = Regularization.Simple(meshObj, alpha_s=0.01, alpha_x=1., alpha_y=1., alpha_z=1., cell_weights=W) opt = Optimization.ProjectedGNCG(maxIter=20, lower=0., upper=1e-2, maxIterLS=20, tolCG=1e-4) invProb = InvProblem.BaseInvProblem(dmis, reg, opt) directives = [ Directives.BetaSchedule(coolingFactor=2, coolingRate=1), Directives.TargetMisfit() ] inv = Inversion.BaseInversion(invProb, directiveList=directives) m0 = 1e-6 * np.ones(len(mod)) mrec = inv.run(m0) dmis_final = np.sum( (dmis.W.diagonal() * (Survey.dobs - Problem.fields(mrec)))**2) mod_err_2 = np.sqrt(np.sum((mrec - mod)**2)) / np.size(mod) mod_err_inf = np.max(np.abs(mrec - mod)) self.assertTrue(dmis_final < Survey.nD and mod_err_2 < 5e-6 and mod_err_inf < np.max(mod))
def run(N=100, plotIt=True): np.random.seed(1) mesh = Mesh.TensorMesh([N]) nk = 20 jk = np.linspace(1., 60., nk) p = -0.25 q = 0.25 def g(k): return (np.exp(p * jk[k] * mesh.vectorCCx) * np.cos(np.pi * q * jk[k] * mesh.vectorCCx)) G = np.empty((nk, mesh.nC)) for i in range(nk): G[i, :] = g(i) mtrue = np.zeros(mesh.nC) mtrue[mesh.vectorCCx > 0.3] = 1. mtrue[mesh.vectorCCx > 0.45] = -0.5 mtrue[mesh.vectorCCx > 0.6] = 0 prob = Problem.LinearProblem(mesh, G=G) survey = Survey.LinearSurvey() survey.pair(prob) survey.makeSyntheticData(mtrue, std=0.01) M = prob.mesh reg = Regularization.Tikhonov(mesh, alpha_s=1., alpha_x=1.) dmis = DataMisfit.l2_DataMisfit(survey) opt = Optimization.InexactGaussNewton(maxIter=60) invProb = InvProblem.BaseInvProblem(dmis, reg, opt) directives = [ Directives.BetaEstimate_ByEig(beta0_ratio=1e-2), Directives.TargetMisfit() ] inv = Inversion.BaseInversion(invProb, directiveList=directives) m0 = np.zeros_like(survey.mtrue) mrec = inv.run(m0) if plotIt: fig, axes = plt.subplots(1, 2, figsize=(12 * 1.2, 4 * 1.2)) for i in range(prob.G.shape[0]): axes[0].plot(prob.G[i, :]) axes[0].set_title('Columns of matrix G') axes[1].plot(M.vectorCCx, survey.mtrue, 'b-') axes[1].plot(M.vectorCCx, mrec, 'r-') axes[1].legend(('True Model', 'Recovered Model')) axes[1].set_ylim([-2, 2]) return prob, survey, mesh, mrec
def fit_colecole_with_se(self, eta_cc=0.8, tau_cc=0.003, c_cc=0.6): def ColeColeSeigel(f, sigmaInf, eta, tau, c): w = 2 * np.pi * f return sigmaInf * (1 - eta / (1 + (1j * w * tau)**c)) # Step1: Fit Cole-Cole with Stretched Exponential function time = np.logspace(-6, np.log10(0.01), 41) wt, tbase, omega_int = DigFilter.setFrequency(time) frequency = omega_int / (2 * np.pi) # Cole-Cole parameters siginf = 1. self.eta_cc = eta_cc self.tau_cc = tau_cc self.c_cc = c_cc sigma = ColeColeSeigel(frequency, siginf, eta_cc, tau_cc, c_cc) sigTCole = DigFilter.transFiltImpulse(sigma, wt, tbase, omega_int, time, tol=1e-12) wires = Maps.Wires(('eta', 1), ('tau', 1), ('c', 1)) taumap = Maps.ExpMap(nP=1) * wires.tau survey = SESurvey() dtrue = -sigTCole survey.dobs = dtrue m1D = Mesh.TensorMesh([np.ones(3)]) prob = SEInvImpulseProblem(m1D, etaMap=wires.eta, tauMap=taumap, cMap=wires.c) update_sens = Directives.UpdateSensitivityWeights() prob.time = time prob.pair(survey) m0 = np.r_[eta_cc, np.log(tau_cc), c_cc] perc = 0.05 dmisfitpeta = DataMisfit.l2_DataMisfit(survey) dmisfitpeta.W = 1 / (abs(survey.dobs) * perc) reg = regularization.Simple(m1D) opt = Optimization.ProjectedGNCG(maxIter=10) invProb = InvProblem.BaseInvProblem(dmisfitpeta, reg, opt) # Create an inversion object target = Directives.TargetMisfit() invProb.beta = 0. inv = Inversion.BaseInversion(invProb, directiveList=[target]) reg.mref = 0. * m0 prob.counter = opt.counter = Utils.Counter() opt.LSshorten = 0.5 opt.remember('xc') opt.tolX = 1e-20 opt.tolF = 1e-20 opt.tolG = 1e-20 opt.eps = 1e-20 mopt = inv.run(m0) return mopt
def test_validation_pass(self): betaest = Directives.BetaEstimate_ByEig() IRLS = Directives.Update_IRLS(f_min_change=1e-4, minGNiter=3, beta_tol=1e-2) update_Jacobi = Directives.Update_lin_PreCond() dList = [betaest, IRLS, update_Jacobi] directiveList = Directives.DirectiveList(*dList) self.assertTrue(directiveList.validate())
def test_validation_fail(self): betaest = Directives.BetaEstimate_ByEig() IRLS = Directives.Update_IRLS(f_min_change=1e-4, minGNiter=3, beta_tol=1e-2) update_Jacobi = Directives.Update_lin_PreCond() dList = [betaest, update_Jacobi, IRLS] directiveList = Directives.DirectiveList(*dList) with self.assertRaises(AssertionError): self.assertTrue(directiveList.validate())
def test_validation_warning(self): betaest = Directives.BetaEstimate_ByEig() IRLS = Directives.Update_IRLS(f_min_change=1e-4, minGNiter=3, beta_tol=1e-2) update_Jacobi = Directives.Update_lin_PreCond() dList = [betaest, IRLS] directiveList = Directives.DirectiveList(*dList) with pytest.warns(UserWarning): self.assertTrue(directiveList.validate())
def solve(self): # Tikhonov Inversion #################### # Initial model values m0 = np.median(self.ln_sigback) * np.ones(self.mapping.nP) m0 += np.random.randn(m0.size) # Misfit functional dmis = DataMisfit.l2_DataMisfit(self.survey.simpeg_survey) # Regularization functional regT = Regularization.Simple(self.mesh, alpha_s=10.0, alpha_x=10.0, alpha_y=10.0, alpha_z=10.0, indActive=self.actind) # Personal preference for this solver with a Jacobi preconditioner opt = Optimization.ProjectedGNCG(maxIter=8, tolX=1, maxIterCG=30) #opt = Optimization.ProjectedGradient(maxIter=100, tolX=1e-2, # maxIterLS=20, maxIterCG=30, tolCG=1e-4) opt.printers.append(Optimization.IterationPrinters.iterationLS) #print(opt.printersLS) # Optimization class keeps value of 'xc'. Seems to be solution for the model parameters opt.remember('xc') invProb = InvProblem.BaseInvProblem(dmis, regT, opt) # Options for the inversion algorithm in particular selection of Beta weight for regularization. # How to choose initial estimate for beta beta = Directives.BetaEstimate_ByEig(beta0_ratio=1.) Target = Directives.TargetMisfit() # Beta changing algorithm. betaSched = Directives.BetaSchedule(coolingFactor=5., coolingRate=2) # Change model weights, seems sensitivity of conductivity ?? Not sure. updateSensW = Directives.UpdateSensitivityWeights(threshold=1e-3) # Use Jacobi preconditioner ( the only available). update_Jacobi = Directives.UpdatePreconditioner() inv = Inversion.BaseInversion(invProb, directiveList=[ beta, Target, betaSched, updateSensW, update_Jacobi ]) self.minv = inv.run(m0)
def test_inv(self): reg = Regularization.Tikhonov(self.mesh) opt = Optimization.InexactGaussNewton(maxIter=10) invProb = InvProblem.BaseInvProblem(self.dmiscobmo, reg, opt) directives = [ Directives.BetaEstimate_ByEig(beta0_ratio=1e-2), ] inv = Inversion.BaseInversion(invProb, directiveList=directives) m0 = self.model.mean() * np.ones_like(self.model) mrec = inv.run(m0)
def test_validation_in_inversion(self): betaest = Directives.BetaEstimate_ByEig() # Here is where the norms are applied IRLS = Directives.Update_IRLS(f_min_change=1e-4, minGNiter=3, beta_tol=1e-2) update_Jacobi = Directives.Update_lin_PreCond() with self.assertRaises(AssertionError): # validation should happen and this will fail # (IRLS needs to be before update_Jacobi) inv = Inversion.BaseInversion( self.invProb, directiveList=[betaest, update_Jacobi, IRLS]) with self.assertRaises(AssertionError): # validation should happen and this will fail # (IRLS needs to be before update_Jacobi) inv = Inversion.BaseInversion(self.invProb) inv.directiveList = [betaest, update_Jacobi, IRLS]
def solve(self): # initial values/model m0 = numpy.median(-4) * numpy.ones(self.mapping.nP) # Data Misfit dataMisfit = DataMisfit.l2_DataMisfit(self.survey) # Regularization regT = Regularization.Simple(self.mesh, indActive=self.activeCellIndices, alpha_s=1e-6, alpha_x=1., alpha_y=1., alpha_z=1.) # Optimization Scheme opt = Optimization.InexactGaussNewton(maxIter=10) # Form the problem opt.remember('xc') invProb = InvProblem.BaseInvProblem(dataMisfit, regT, opt) # Directives for Inversions beta = Directives.BetaEstimate_ByEig(beta0_ratio=0.5e+1) Target = Directives.TargetMisfit() betaSched = Directives.BetaSchedule(coolingFactor=5., coolingRate=2) inversion = Inversion.BaseInversion(invProb, directiveList=[beta, Target, betaSched]) # Run Inversion self.invModelOnActiveCells = inversion.run(m0) self.invModelOnAllCells = self.givenModelCond * numpy.ones_like(self.givenModelCond) self.invModelOnAllCells[self.activeCellIndices] = self.invModelOnActiveCells self.invModelOnCoreCells = self.invModelOnAllCells[self.coreMeshCellIndices] pass
def test_inv_mref_setting(self): reg1 = Regularization.Tikhonov(self.mesh) reg2 = Regularization.Tikhonov(self.mesh) reg = reg1 + reg2 opt = Optimization.InexactGaussNewton(maxIter=10) invProb = InvProblem.BaseInvProblem(self.dmiscobmo, reg, opt) directives = [ Directives.BetaEstimate_ByEig(beta0_ratio=1e-2), ] inv = Inversion.BaseInversion(invProb, directiveList=directives) m0 = self.model.mean() * np.ones_like(self.model) mrec = inv.run(m0) self.assertTrue(np.all(reg1.mref == m0)) self.assertTrue(np.all(reg2.mref == m0))
# Setup and run inversion dmis = DataMisfit.l2_DataMisfit(survey_inv) w = mkvc((np.sum(np.array(problem_inv.A)**2, axis=0)))**0.5 w = w / np.max(w) reg = Regularization.Simple(mesh=mesh, indActive=actCells, alpha_s=0.25, cell_weights=w) opt = Optimization.ProjectedGNCG(maxIter=20, lower=0., upper=1e-2, maxIterLS=20, tolCG=1e-4) invProb = InvProblem.BaseInvProblem(dmis, reg, opt) directives = [ Directives.BetaSchedule(coolingFactor=2, coolingRate=1), Directives.TargetMisfit() ] inv = Inversion.BaseInversion(invProb, directiveList=directives) xi_0 = 1e-3 * np.ones(actCells.sum()) xi_rec = inv.run(xi_0) # Predict VRM response at all times for recovered model survey_inv.set_active_interval(0., 1.) fields_pre = survey_inv.dpred(xi_rec) ################################ # Plotting # -------- #
def setUp(self): ndv = -100 # Create a mesh dx = 5. hxind = [(dx, 5, -1.3), (dx, 5), (dx, 5, 1.3)] hyind = [(dx, 5, -1.3), (dx, 5), (dx, 5, 1.3)] hzind = [(dx, 5, -1.3), (dx, 6)] mesh = Mesh.TensorMesh([hxind, hyind, hzind], 'CCC') # Get index of the center midx = int(mesh.nCx/2) midy = int(mesh.nCy/2) # Lets create a simple Gaussian topo and set the active cells [xx, yy] = np.meshgrid(mesh.vectorNx, mesh.vectorNy) zz = -np.exp((xx**2 + yy**2) / 75**2) + mesh.vectorNz[-1] # Go from topo to actv cells topo = np.c_[Utils.mkvc(xx), Utils.mkvc(yy), Utils.mkvc(zz)] actv = Utils.surface2ind_topo(mesh, topo, 'N') actv = np.asarray([inds for inds, elem in enumerate(actv, 1) if elem], dtype=int) - 1 # Create active map to go from reduce space to full actvMap = Maps.InjectActiveCells(mesh, actv, -100) nC = len(actv) # Create and array of observation points xr = np.linspace(-20., 20., 20) yr = np.linspace(-20., 20., 20) X, Y = np.meshgrid(xr, yr) # Move the observation points 5m above the topo Z = -np.exp((X**2 + Y**2) / 75**2) + mesh.vectorNz[-1] + 5. # Create a MAGsurvey locXYZ = np.c_[Utils.mkvc(X.T), Utils.mkvc(Y.T), Utils.mkvc(Z.T)] rxLoc = PF.BaseGrav.RxObs(locXYZ) srcField = PF.BaseGrav.SrcField([rxLoc]) survey = PF.BaseGrav.LinearSurvey(srcField) # We can now create a density model and generate data # Here a simple block in half-space model = np.zeros((mesh.nCx, mesh.nCy, mesh.nCz)) model[(midx-2):(midx+2), (midy-2):(midy+2), -6:-2] = 0.5 model = Utils.mkvc(model) self.model = model[actv] # Create active map to go from reduce set to full actvMap = Maps.InjectActiveCells(mesh, actv, ndv) # Create reduced identity map idenMap = Maps.IdentityMap(nP=nC) # Create the forward model operator prob = PF.Gravity.GravityIntegral( mesh, rhoMap=idenMap, actInd=actv ) # Pair the survey and problem survey.pair(prob) # Compute linear forward operator and compute some data d = prob.fields(self.model) # Add noise and uncertainties (1nT) data = d + np.random.randn(len(d))*0.001 wd = np.ones(len(data))*.001 survey.dobs = data survey.std = wd # PF.Gravity.plot_obs_2D(survey.srcField.rxList[0].locs, d=data) # Create sensitivity weights from our linear forward operator wr = PF.Magnetics.get_dist_wgt(mesh, locXYZ, actv, 2., 2.) wr = wr**2. # Create a regularization reg = Regularization.Sparse(mesh, indActive=actv, mapping=idenMap) reg.cell_weights = wr reg.norms = [0, 1, 1, 1] reg.eps_p, reg.eps_q = 5e-2, 1e-2 # Data misfit function dmis = DataMisfit.l2_DataMisfit(survey) dmis.W = 1/wd # Add directives to the inversion opt = Optimization.ProjectedGNCG(maxIter=100, lower=-1., upper=1., maxIterLS=20, maxIterCG=10, tolCG=1e-3) invProb = InvProblem.BaseInvProblem(dmis, reg, opt, beta=1e+8) # Here is where the norms are applied IRLS = Directives.Update_IRLS(f_min_change=1e-3, minGNiter=3) update_Jacobi = Directives.Update_lin_PreCond(mapping=idenMap) self.inv = Inversion.BaseInversion(invProb, directiveList=[IRLS, update_Jacobi])
ax[0].set_xlim(-1000., 1000.) ax[0].set_ylim(-500., 0.) ############################################################################### # Step 6 # ------ # # Run inversion regmesh = Mesh.TensorMesh([31]) dmis = DataMisfit.l2_DataMisfit(survey) reg = Regularization.Tikhonov(regmesh) opt = Optimization.InexactGaussNewton(maxIter=7, tolX=1e-15) opt.remember('xc') invProb = InvProblem.BaseInvProblem(dmis, reg, opt) beta = Directives.BetaEstimate_ByEig(beta0_ratio=1e1) betaSched = Directives.BetaSchedule(coolingFactor=5, coolingRate=2) inv = Inversion.BaseInversion(invProb, directiveList=[beta, betaSched]) # Choose an initial starting model of the background conductivity m0 = np.log(np.ones(mapping.nP) * sighalf) mopt = inv.run(m0) ############################################################################### # Step 7 # ------ # # Plot the results appres = data * np.pi * b * (b + a) / a appres_obs = survey.dobs * np.pi * b * (b + a) / a appres_pred = invProb.dpred * np.pi * b * (b + a) / a
reg.mref = np.zeros(nC) # Specify how the optimization will proceed, set susceptibility bounds to inf opt = Optimization.ProjectedGNCG(maxIter=25, lower=-np.inf, upper=np.inf, maxIterLS=20, maxIterCG=20, tolCG=1e-3) # Define misfit function (obs-calc) dmis = DataMisfit.l2_DataMisfit(survey) dmis.W = 1./survey.std # Create the default L2 inverse problem from the above objects invProb = InvProblem.BaseInvProblem(dmis, reg, opt) # Specify how the initial beta is found betaest = Directives.BetaEstimate_ByEig() # Beta schedule for inversion betaSchedule = Directives.BetaSchedule(coolingFactor=2., coolingRate=1) # Target misfit to stop the inversion, # try to fit as much as possible of the signal, we don't want to lose anything targetMisfit = Directives.TargetMisfit(chifact=0.1) # Put all the parts together inv = Inversion.BaseInversion(invProb, directiveList=[betaest, betaSchedule, targetMisfit]) # Run the equivalent source inversion mstart = np.zeros(nC) mrec = inv.run(mstart)
def run(plotIt=True, cleanAfterRun=True): # Start by downloading files from the remote repository # directory where the downloaded files are url = "https://storage.googleapis.com/simpeg/Chile_GRAV_4_Miller/Chile_GRAV_4_Miller.tar.gz" downloads = download(url, overwrite=True) basePath = downloads.split(".")[0] # unzip the tarfile tar = tarfile.open(downloads, "r") tar.extractall() tar.close() input_file = basePath + os.path.sep + 'LdM_input_file.inp' # %% User input # Plotting parameters, max and min densities in g/cc vmin = -0.6 vmax = 0.6 # weight exponent for default weighting wgtexp = 3. # %% # Read in the input file which included all parameters at once # (mesh, topo, model, survey, inv param, etc.) driver = PF.GravityDriver.GravityDriver_Inv(input_file) # %% # Now we need to create the survey and model information. # Access the mesh and survey information mesh = driver.mesh survey = driver.survey # define gravity survey locations rxLoc = survey.srcField.rxList[0].locs # define gravity data and errors d = survey.dobs wd = survey.std # Get the active cells active = driver.activeCells nC = len(active) # Number of active cells # Create active map to go from reduce set to full activeMap = Maps.InjectActiveCells(mesh, active, -100) # Create static map static = driver.staticCells dynamic = driver.dynamicCells staticCells = Maps.InjectActiveCells(None, dynamic, driver.m0[static], nC=nC) mstart = driver.m0[dynamic] # Get index of the center midx = int(mesh.nCx / 2) # %% # Now that we have a model and a survey we can build the linear system ... # Create the forward model operator prob = PF.Gravity.GravityIntegral(mesh, rhoMap=staticCells, actInd=active) prob.solverOpts['accuracyTol'] = 1e-4 # Pair the survey and problem survey.pair(prob) # Apply depth weighting wr = PF.Magnetics.get_dist_wgt(mesh, rxLoc, active, wgtexp, np.min(mesh.hx) / 4.) wr = wr**2. # %% Create inversion objects reg = Regularization.Sparse(mesh, indActive=active, mapping=staticCells, gradientType='total') reg.mref = driver.mref[dynamic] reg.cell_weights = wr * mesh.vol[active] reg.norms = np.c_[0., 1., 1., 1.] # reg.norms = driver.lpnorms # Specify how the optimization will proceed opt = Optimization.ProjectedGNCG(maxIter=20, lower=driver.bounds[0], upper=driver.bounds[1], maxIterLS=10, maxIterCG=20, tolCG=1e-3) # Define misfit function (obs-calc) dmis = DataMisfit.l2_DataMisfit(survey) dmis.W = 1. / wd # create the default L2 inverse problem from the above objects invProb = InvProblem.BaseInvProblem(dmis, reg, opt) # Specify how the initial beta is found betaest = Directives.BetaEstimate_ByEig(beta0_ratio=1e-2) # IRLS sets up the Lp inversion problem # Set the eps parameter parameter in Line 11 of the # input file based on the distribution of model (DEFAULT = 95th %ile) IRLS = Directives.Update_IRLS(f_min_change=1e-4, maxIRLSiter=40, beta_tol=5e-1) # Preconditioning refreshing for each IRLS iteration update_Jacobi = Directives.UpdatePreconditioner() # Create combined the L2 and Lp problem inv = Inversion.BaseInversion(invProb, directiveList=[IRLS, update_Jacobi, betaest]) # %% # Run L2 and Lp inversion mrec = inv.run(mstart) if cleanAfterRun: os.remove(downloads) shutil.rmtree(basePath) # %% if plotIt: # Plot observed data PF.Magnetics.plot_obs_2D(rxLoc, d, 'Observed Data') # %% # Write output model and data files and print misft stats. # reconstructing l2 model mesh with air cells and active dynamic cells L2out = activeMap * invProb.l2model # reconstructing lp model mesh with air cells and active dynamic cells Lpout = activeMap * mrec # %% # Plot out sections and histograms of the smooth l2 model. # The ind= parameter is the slice of the model from top down. yslice = midx + 1 L2out[L2out == -100] = np.nan # set "air" to nan plt.figure(figsize=(10, 7)) plt.suptitle('Smooth Inversion: Depth weight = ' + str(wgtexp)) ax = plt.subplot(221) dat1 = mesh.plotSlice(L2out, ax=ax, normal='Z', ind=-16, clim=(vmin, vmax), pcolorOpts={'cmap': 'bwr'}) plt.plot(np.array([mesh.vectorCCx[0], mesh.vectorCCx[-1]]), np.array([mesh.vectorCCy[yslice], mesh.vectorCCy[yslice]]), c='gray', linestyle='--') plt.scatter(rxLoc[0:, 0], rxLoc[0:, 1], color='k', s=1) plt.title('Z: ' + str(mesh.vectorCCz[-16]) + ' m') plt.xlabel('Easting (m)') plt.ylabel('Northing (m)') plt.gca().set_aspect('equal', adjustable='box') cb = plt.colorbar(dat1[0], orientation="vertical", ticks=np.linspace(vmin, vmax, 4)) cb.set_label('Density (g/cc$^3$)') ax = plt.subplot(222) dat = mesh.plotSlice(L2out, ax=ax, normal='Z', ind=-27, clim=(vmin, vmax), pcolorOpts={'cmap': 'bwr'}) plt.plot(np.array([mesh.vectorCCx[0], mesh.vectorCCx[-1]]), np.array([mesh.vectorCCy[yslice], mesh.vectorCCy[yslice]]), c='gray', linestyle='--') plt.scatter(rxLoc[0:, 0], rxLoc[0:, 1], color='k', s=1) plt.title('Z: ' + str(mesh.vectorCCz[-27]) + ' m') plt.xlabel('Easting (m)') plt.ylabel('Northing (m)') plt.gca().set_aspect('equal', adjustable='box') cb = plt.colorbar(dat1[0], orientation="vertical", ticks=np.linspace(vmin, vmax, 4)) cb.set_label('Density (g/cc$^3$)') ax = plt.subplot(212) mesh.plotSlice(L2out, ax=ax, normal='Y', ind=yslice, clim=(vmin, vmax), pcolorOpts={'cmap': 'bwr'}) plt.title('Cross Section') plt.xlabel('Easting(m)') plt.ylabel('Elevation') plt.gca().set_aspect('equal', adjustable='box') cb = plt.colorbar(dat1[0], orientation="vertical", ticks=np.linspace(vmin, vmax, 4), cmap='bwr') cb.set_label('Density (g/cc$^3$)') # %% # Make plots of Lp model yslice = midx + 1 Lpout[Lpout == -100] = np.nan # set "air" to nan plt.figure(figsize=(10, 7)) plt.suptitle('Compact Inversion: Depth weight = ' + str(wgtexp) + ': $\epsilon_p$ = ' + str(round(reg.eps_p, 1)) + ': $\epsilon_q$ = ' + str(round(reg.eps_q, 2))) ax = plt.subplot(221) dat = mesh.plotSlice(Lpout, ax=ax, normal='Z', ind=-16, clim=(vmin, vmax), pcolorOpts={'cmap': 'bwr'}) plt.plot(np.array([mesh.vectorCCx[0], mesh.vectorCCx[-1]]), np.array([mesh.vectorCCy[yslice], mesh.vectorCCy[yslice]]), c='gray', linestyle='--') plt.scatter(rxLoc[0:, 0], rxLoc[0:, 1], color='k', s=1) plt.title('Z: ' + str(mesh.vectorCCz[-16]) + ' m') plt.xlabel('Easting (m)') plt.ylabel('Northing (m)') plt.gca().set_aspect('equal', adjustable='box') cb = plt.colorbar(dat[0], orientation="vertical", ticks=np.linspace(vmin, vmax, 4)) cb.set_label('Density (g/cc$^3$)') ax = plt.subplot(222) dat = mesh.plotSlice(Lpout, ax=ax, normal='Z', ind=-27, clim=(vmin, vmax), pcolorOpts={'cmap': 'bwr'}) plt.plot(np.array([mesh.vectorCCx[0], mesh.vectorCCx[-1]]), np.array([mesh.vectorCCy[yslice], mesh.vectorCCy[yslice]]), c='gray', linestyle='--') plt.scatter(rxLoc[0:, 0], rxLoc[0:, 1], color='k', s=1) plt.title('Z: ' + str(mesh.vectorCCz[-27]) + ' m') plt.xlabel('Easting (m)') plt.ylabel('Northing (m)') plt.gca().set_aspect('equal', adjustable='box') cb = plt.colorbar(dat[0], orientation="vertical", ticks=np.linspace(vmin, vmax, 4)) cb.set_label('Density (g/cc$^3$)') ax = plt.subplot(212) dat = mesh.plotSlice(Lpout, ax=ax, normal='Y', ind=yslice, clim=(vmin, vmax), pcolorOpts={'cmap': 'bwr'}) plt.title('Cross Section') plt.xlabel('Easting (m)') plt.ylabel('Elevation (m)') plt.gca().set_aspect('equal', adjustable='box') cb = plt.colorbar(dat[0], orientation="vertical", ticks=np.linspace(vmin, vmax, 4)) cb.set_label('Density (g/cc$^3$)')
def run(plotIt=True): cs, ncx, ncz, npad = 5., 25, 15, 15 hx = [(cs, ncx), (cs, npad, 1.3)] hz = [(cs, npad, -1.3), (cs, ncz), (cs, npad, 1.3)] mesh = Mesh.CylMesh([hx, 1, hz], '00C') layerz = -100. active = mesh.vectorCCz < 0. layer = (mesh.vectorCCz < 0.) & (mesh.vectorCCz >= layerz) actMap = Maps.InjectActiveCells(mesh, active, np.log(1e-8), nC=mesh.nCz) mapping = Maps.ExpMap(mesh) * Maps.SurjectVertical1D(mesh) * actMap sig_half = 2e-2 sig_air = 1e-8 sig_layer = 1e-2 sigma = np.ones(mesh.nCz) * sig_air sigma[active] = sig_half sigma[layer] = sig_layer mtrue = np.log(sigma[active]) if plotIt: fig, ax = plt.subplots(1, 1, figsize=(3, 6)) plt.semilogx(sigma[active], mesh.vectorCCz[active]) ax.set_ylim(-500, 0) ax.set_xlim(1e-3, 1e-1) ax.set_xlabel('Conductivity (S/m)', fontsize=14) ax.set_ylabel('Depth (m)', fontsize=14) ax.grid(color='k', alpha=0.5, linestyle='dashed', linewidth=0.5) rxOffset = 10. bzi = EM.FDEM.Rx.Point_b(np.array([[rxOffset, 0., 1e-3]]), orientation='z', component='imag') freqs = np.logspace(1, 3, 10) srcLoc = np.array([0., 0., 10.]) srcList = [ EM.FDEM.Src.MagDipole([bzi], freq, srcLoc, orientation='Z') for freq in freqs ] survey = EM.FDEM.Survey(srcList) prb = EM.FDEM.Problem3D_b(mesh, sigmaMap=mapping, Solver=Solver) prb.pair(survey) std = 0.05 survey.makeSyntheticData(mtrue, std) survey.std = std survey.eps = np.linalg.norm(survey.dtrue) * 1e-5 if plotIt: fig, ax = plt.subplots(1, 1, figsize=(6, 6)) ax.semilogx(freqs, survey.dtrue[:freqs.size], 'b.-') ax.semilogx(freqs, survey.dobs[:freqs.size], 'r.-') ax.legend(('Noisefree', '$d^{obs}$'), fontsize=16) ax.set_xlabel('Time (s)', fontsize=14) ax.set_ylabel('$B_z$ (T)', fontsize=16) ax.set_xlabel('Time (s)', fontsize=14) ax.grid(color='k', alpha=0.5, linestyle='dashed', linewidth=0.5) dmisfit = DataMisfit.l2_DataMisfit(survey) regMesh = Mesh.TensorMesh([mesh.hz[mapping.maps[-1].indActive]]) reg = Regularization.Tikhonov(regMesh) opt = Optimization.InexactGaussNewton(maxIter=6) invProb = InvProblem.BaseInvProblem(dmisfit, reg, opt) # Create an inversion object beta = Directives.BetaSchedule(coolingFactor=5, coolingRate=2) betaest = Directives.BetaEstimate_ByEig(beta0_ratio=1e0) inv = Inversion.BaseInversion(invProb, directiveList=[beta, betaest]) m0 = np.log(np.ones(mtrue.size) * sig_half) reg.alpha_s = 1e-3 reg.alpha_x = 1. prb.counter = opt.counter = Utils.Counter() opt.LSshorten = 0.5 opt.remember('xc') mopt = inv.run(m0) if plotIt: fig, ax = plt.subplots(1, 1, figsize=(3, 6)) plt.semilogx(sigma[active], mesh.vectorCCz[active]) plt.semilogx(np.exp(mopt), mesh.vectorCCz[active]) ax.set_ylim(-500, 0) ax.set_xlim(1e-3, 1e-1) ax.set_xlabel('Conductivity (S/m)', fontsize=14) ax.set_ylabel('Depth (m)', fontsize=14) ax.grid(color='k', alpha=0.5, linestyle='dashed', linewidth=0.5) plt.legend(['$\sigma_{true}$', '$\sigma_{pred}$'], loc='best')
maxIterLS=20, maxIterCG=30, tolCG=1e-3, stepOffBoundsFact=1e-8, LSshorten=0.25 ) # Create the default L2 inverse problem from the above objects invProb = InvProblem.BaseInvProblem(global_misfit, reg, opt, beta=initial_beta) # Add a list of directives to the inversion directiveList = [] if vector_property: # chifact_target (MVIS-only) should be higher than target_chi. # If MVIS has problems, try increasing chifact_target. directiveList.append(Directives.VectorInversion( inversion_type=input_dict["inversion_type"], chifact_target=1.) ) directiveList.append( Directives.Update_IRLS( f_min_change=1e-4, maxIRLSiter=max_irls_iterations, minGNiter=1, beta_tol=0.5, prctile=90, floorEpsEnforced=True, coolingRate=1, coolEps_q=True, coolEpsFact=1.2, betaSearch=False ) ) if initial_beta is None: directiveList.append(Directives.BetaEstimate_ByEig(beta0_ratio=1e+1))
# Data misfit function dmis = DataMisfit.l2_DataMisfit(survey) dmis.W = 1. / survey.std # Add directives to the inversion opt = Optimization.ProjectedGNCG(maxIter=30, lower=-10, upper=10., maxIterLS=20, maxIterCG=20, tolCG=1e-4) invProb = InvProblem.BaseInvProblem(dmis, reg, opt) # A list of directive to control the inverson betaest = Directives.BetaEstimate_ByEig() # Here is where the norms are applied # Use pick a treshold parameter empirically based on the distribution of # model parameters IRLS = Directives.Update_IRLS(f_min_change=1e-3, maxIRLSiter=0, beta_tol=5e-1) # Pre-conditioner update_Jacobi = Directives.UpdatePreconditioner() inv = Inversion.BaseInversion(invProb, directiveList=[IRLS, update_Jacobi, betaest]) # Run the inversion m0 = np.ones(3 * nC) * 1e-4 # Starting model mrec_MVIC = inv.run(m0)
survey.dpred(mtrue) survey.makeSyntheticData(mtrue, std=0.05, force=True) print '# of data: ', survey.dobs.shape #Simple Inversion regmesh = mesh m0 = (-5.) * np.ones(mapping.nP) dmis = DataMisfit.l2_DataMisfit(survey) reg = Regularization.Tikhonov(regmesh) #,mapping = mapping)#,indActive=actind) reg.mref = m0 opt = Optimization.InexactGaussNewton(maxIter=20, tolX=1e-6) opt.remember('xc') invProb = InvProblem.BaseInvProblem(dmis, reg, opt) beta = Directives.BetaEstimate_ByEig(beta0=10., beta0_ratio=1e0) reg.alpha_s = 1e-2 #beta = 0. #invProb.beta = beta betaSched = Directives.BetaSchedule(coolingFactor=5, coolingRate=2) #sav0 = Directives.SaveEveryIteration() #sav1 = Directives.SaveModelEveryIteration() sav2 = Directives.SaveOutputDictEveryIteration() inv = Inversion.BaseInversion(invProb, directiveList=[sav2, beta, betaSched]) #sav0,sav1, mtest = np.load('../Update_W_each_3it_5s_rademacher/finalresult.npy') print "check misfit with W: ", dmis.eval(mtest) / survey.nD mm = meshCore.plotImage(mtest[actind]) plt.colorbar(mm[0]) plt.show()
def setUp(self): np.random.seed(0) # Define the inducing field parameter H0 = (50000, 90, 0) # Create a mesh dx = 5. hxind = [(dx, 5, -1.3), (dx, 5), (dx, 5, 1.3)] hyind = [(dx, 5, -1.3), (dx, 5), (dx, 5, 1.3)] hzind = [(dx, 5, -1.3), (dx, 6)] mesh = Mesh.TensorMesh([hxind, hyind, hzind], 'CCC') # Get index of the center midx = int(mesh.nCx / 2) midy = int(mesh.nCy / 2) # Lets create a simple Gaussian topo and set the active cells [xx, yy] = np.meshgrid(mesh.vectorNx, mesh.vectorNy) zz = -np.exp((xx**2 + yy**2) / 75**2) + mesh.vectorNz[-1] # Go from topo to actv cells topo = np.c_[Utils.mkvc(xx), Utils.mkvc(yy), Utils.mkvc(zz)] actv = Utils.surface2ind_topo(mesh, topo, 'N') actv = np.asarray([inds for inds, elem in enumerate(actv, 1) if elem], dtype=int) - 1 # Create active map to go from reduce space to full actvMap = Maps.InjectActiveCells(mesh, actv, -100) nC = len(actv) # Create and array of observation points xr = np.linspace(-20., 20., 20) yr = np.linspace(-20., 20., 20) X, Y = np.meshgrid(xr, yr) # Move the observation points 5m above the topo Z = -np.exp((X**2 + Y**2) / 75**2) + mesh.vectorNz[-1] + 5. # Create a MAGsurvey rxLoc = np.c_[Utils.mkvc(X.T), Utils.mkvc(Y.T), Utils.mkvc(Z.T)] rxLoc = PF.BaseMag.RxObs(rxLoc) srcField = PF.BaseMag.SrcField([rxLoc], param=H0) survey = PF.BaseMag.LinearSurvey(srcField) # We can now create a susceptibility model and generate data # Here a simple block in half-space model = np.zeros((mesh.nCx, mesh.nCy, mesh.nCz)) model[(midx - 2):(midx + 2), (midy - 2):(midy + 2), -6:-2] = 0.02 model = Utils.mkvc(model) self.model = model[actv] # Create active map to go from reduce set to full actvMap = Maps.InjectActiveCells(mesh, actv, -100) # Creat reduced identity map idenMap = Maps.IdentityMap(nP=nC) # Create the forward model operator prob = PF.Magnetics.MagneticIntegral(mesh, chiMap=idenMap, actInd=actv) # Pair the survey and problem survey.pair(prob) # Compute linear forward operator and compute some data d = prob.fields(self.model) # Add noise and uncertainties (1nT) data = d + np.random.randn(len(d)) wd = np.ones(len(data)) * 1. survey.dobs = data survey.std = wd # Create sensitivity weights from our linear forward operator wr = np.sum(prob.G**2., axis=0)**0.5 wr = (wr / np.max(wr)) # Create a regularization reg = Regularization.Sparse(mesh, indActive=actv, mapping=idenMap) reg.cell_weights = wr reg.norms = np.c_[0, 0, 0, 0] reg.gradientType = 'component' # reg.eps_p, reg.eps_q = 1e-3, 1e-3 # Data misfit function dmis = DataMisfit.l2_DataMisfit(survey) dmis.W = 1 / wd # Add directives to the inversion opt = Optimization.ProjectedGNCG(maxIter=100, lower=0., upper=1., maxIterLS=20, maxIterCG=10, tolCG=1e-3) invProb = InvProblem.BaseInvProblem(dmis, reg, opt) betaest = Directives.BetaEstimate_ByEig() # Here is where the norms are applied IRLS = Directives.Update_IRLS(f_min_change=1e-4, minGNiter=1) update_Jacobi = Directives.UpdatePreconditioner() self.inv = Inversion.BaseInversion( invProb, directiveList=[IRLS, betaest, update_Jacobi])
reg.cell_weights = wr reg.mref = driver.mref # Data misfit function dmis = DataMisfit.l2_DataMisfit(survey) dmis.W = 1. / survey.std # Add directives to the inversion opt = Optimization.ProjectedGNCG(maxIter=20, lower=0., upper=10., maxIterLS=20, maxIterCG=10, tolCG=1e-4) invProb = InvProblem.BaseInvProblem(dmis, reg, opt) betaest = Directives.BetaEstimate_ByEig() # Here is where the norms are applied # Use pick a treshold parameter empirically based on the distribution of # model parameters IRLS = Directives.Update_IRLS(f_min_change=1e-3, minGNiter=3, maxIRLSiter=10, chifact=5) update_Jacobi = Directives.UpdatePreCond() saveModel = Directives.SaveUBCModelEveryIteration(mapping=actvMap) saveModel.fileName = work_dir + out_dir + '\\ModelSus' inv = Inversion.BaseInversion(
reg.cell_weights = wr # reg.norms = [0, 1, 1, 1] # reg.eps_p, reg.eps_q = 1e-3, 1e-3 mesh.writeModelUBC('J1.dat', actvMap * wr) mesh.writeModelUBC('J.dat', actvMap * np.sum(prob.G**2., axis=0)) # Add directives to the inversion opt = Optimization.ProjectedGNCG(maxIter=100, lower=0., upper=1., maxIterLS=20, maxIterCG=10, tolCG=1e-3) invProb = InvProblem.BaseInvProblem(globalMisfit, reg, opt) betaest = Directives.BetaEstimate_ByEig() # Here is where the norms are applied # Use pick a treshold parameter empirically based on the distribution of # model parameters IRLS = Directives.Update_IRLS(f_min_change=1e-3, minGNiter=3) update_Jacobi = Directives.UpdatePreconditioner() inv = Inversion.BaseInversion(invProb, directiveList=[IRLS, betaest, update_Jacobi]) # Run the inversion m0 = np.ones(nC) * 1e-4 # Starting model mrec = inv.run(m0) mesh.writeModelUBC('Mrec.sus', actvMap * mrec)
reg.mref = mref # Specify how the optimization will proceed, set susceptibility bounds to inf opt = Optimization.ProjectedGNCG(maxIter=25, lower=-np.inf, upper=np.inf, maxIterLS=20, maxIterCG=30, tolCG=1e-3) # Create the default L2 inverse problem from the above objects invProb = InvProblem.BaseInvProblem(global_misfit, reg, opt) # Specify how the initial beta is found # if input_dict["inversion_type"].lower() in ['mvi', 'mvis']: betaest = Directives.BetaEstimate_ByEig(beta0_ratio=1e+1) # Pre-conditioner update_Jacobi = Directives.UpdatePreconditioner() IRLS = Directives.Update_IRLS(f_min_change=1e-3, minGNiter=1, beta_tol=0.25, maxIRLSiter=max_IRLS_iter, chifact_target=target_chi, betaSearch=False) # Save model saveDict = Directives.SaveOutputEveryIteration(save_txt=False) saveIt = Directives.SaveUBCModelEveryIteration( mapping=activeCellsMap,
regT = Regularization.Simple(mesh, indActive=actind, alpha_s=1e-6, alpha_x=1., alpha_y=1., alpha_z=1.) # Optimization Scheme opt = Optimization.InexactGaussNewton(maxIter=10) # Form the problem opt.remember('xc') invProb = InvProblem.BaseInvProblem(dmis, regT, opt) # Directives for Inversions beta = Directives.BetaEstimate_ByEig(beta0_ratio=1e+1) Target = Directives.TargetMisfit() betaSched = Directives.BetaSchedule(coolingFactor=5., coolingRate=2) inv = Inversion.BaseInversion(invProb, directiveList=[beta, Target, betaSched]) # Run Inversion minv = inv.run(m0) # Final Plot ############ fig, ax = plt.subplots(2, 2, figsize=(12, 6)) ax = Utils.mkvc(ax) cyl0v = getCylinderPoints(x0, z0, r0) cyl1v = getCylinderPoints(x1, z1, r1)
def setUp(self): np.random.seed(0) H0 = (50000., 90., 0.) # The magnetization is set along a different # direction (induced + remanence) M = np.array([45., 90.]) # Create grid of points for topography # Lets create a simple Gaussian topo # and set the active cells [xx, yy] = np.meshgrid( np.linspace(-200, 200, 50), np.linspace(-200, 200, 50) ) b = 100 A = 50 zz = A*np.exp(-0.5*((xx/b)**2. + (yy/b)**2.)) # We would usually load a topofile topo = np.c_[Utils.mkvc(xx), Utils.mkvc(yy), Utils.mkvc(zz)] # Create and array of observation points xr = np.linspace(-100., 100., 20) yr = np.linspace(-100., 100., 20) X, Y = np.meshgrid(xr, yr) Z = A*np.exp(-0.5*((X/b)**2. + (Y/b)**2.)) + 5 # Create a MAGsurvey xyzLoc = np.c_[Utils.mkvc(X.T), Utils.mkvc(Y.T), Utils.mkvc(Z.T)] rxLoc = PF.BaseMag.RxObs(xyzLoc) srcField = PF.BaseMag.SrcField([rxLoc], param=H0) survey = PF.BaseMag.LinearSurvey(srcField) # Create a mesh h = [5, 5, 5] padDist = np.ones((3, 2)) * 100 nCpad = [2, 4, 2] # Get extent of points limx = np.r_[topo[:, 0].max(), topo[:, 0].min()] limy = np.r_[topo[:, 1].max(), topo[:, 1].min()] limz = np.r_[topo[:, 2].max(), topo[:, 2].min()] # Get center of the mesh midX = np.mean(limx) midY = np.mean(limy) midZ = np.mean(limz) nCx = int(limx[0]-limx[1]) / h[0] nCy = int(limy[0]-limy[1]) / h[1] nCz = int(limz[0]-limz[1]+int(np.min(np.r_[nCx, nCy])/3)) / h[2] # Figure out full extent required from input extent = np.max(np.r_[nCx * h[0] + padDist[0, :].sum(), nCy * h[1] + padDist[1, :].sum(), nCz * h[2] + padDist[2, :].sum()]) maxLevel = int(np.log2(extent/h[0]))+1 # Number of cells at the small octree level nCx, nCy, nCz = 2**(maxLevel), 2**(maxLevel), 2**(maxLevel) # Define the mesh and origin # For now cubic cells mesh = Mesh.TreeMesh([np.ones(nCx)*h[0], np.ones(nCx)*h[1], np.ones(nCx)*h[2]]) # Set origin mesh.x0 = np.r_[ -nCx*h[0]/2.+midX, -nCy*h[1]/2.+midY, -nCz*h[2]/2.+midZ ] # Refine the mesh around topography # Get extent of points F = NearestNDInterpolator(topo[:, :2], topo[:, 2]) zOffset = 0 # Cycle through the first 3 octree levels for ii in range(3): dx = mesh.hx.min()*2**ii nCx = int((limx[0]-limx[1]) / dx) nCy = int((limy[0]-limy[1]) / dx) # Create a grid at the octree level in xy CCx, CCy = np.meshgrid( np.linspace(limx[1], limx[0], nCx), np.linspace(limy[1], limy[0], nCy) ) z = F(mkvc(CCx), mkvc(CCy)) # level means number of layers in current OcTree level for level in range(int(nCpad[ii])): mesh.insert_cells( np.c_[ mkvc(CCx), mkvc(CCy), z-zOffset ], np.ones_like(z)*maxLevel-ii, finalize=False ) zOffset += dx mesh.finalize() self.mesh = mesh # Define an active cells from topo actv = Utils.surface2ind_topo(mesh, topo) nC = int(actv.sum()) model = np.zeros((mesh.nC, 3)) # Convert the inclination declination to vector in Cartesian M_xyz = Utils.matutils.dip_azimuth2cartesian(M[0], M[1]) # Get the indicies of the magnetized block ind = Utils.ModelBuilder.getIndicesBlock( np.r_[-20, -20, -10], np.r_[20, 20, 25], mesh.gridCC, )[0] # Assign magnetization values model[ind, :] = np.kron( np.ones((ind.shape[0], 1)), M_xyz*0.05 ) # Remove air cells self.model = model[actv, :] # Create active map to go from reduce set to full self.actvMap = Maps.InjectActiveCells(mesh, actv, np.nan) # Creat reduced identity map idenMap = Maps.IdentityMap(nP=nC*3) # Create the forward model operator prob = PF.Magnetics.MagneticIntegral( mesh, chiMap=idenMap, actInd=actv, modelType='vector' ) # Pair the survey and problem survey.pair(prob) # Compute some data and add some random noise data = prob.fields(Utils.mkvc(self.model)) std = 5 # nT data += np.random.randn(len(data))*std wd = np.ones(len(data))*std # Assigne data and uncertainties to the survey survey.dobs = data survey.std = wd # Create an projection matrix for plotting later actvPlot = Maps.InjectActiveCells(mesh, actv, np.nan) # Create sensitivity weights from our linear forward operator rxLoc = survey.srcField.rxList[0].locs # This Mapping connects the regularizations for the three-component # vector model wires = Maps.Wires(('p', nC), ('s', nC), ('t', nC)) # Create sensitivity weights from our linear forward operator # so that all cells get equal chance to contribute to the solution wr = np.sum(prob.G**2., axis=0)**0.5 wr = (wr/np.max(wr)) # Create three regularization for the different components # of magnetization reg_p = Regularization.Sparse(mesh, indActive=actv, mapping=wires.p) reg_p.mref = np.zeros(3*nC) reg_p.cell_weights = (wires.p * wr) reg_s = Regularization.Sparse(mesh, indActive=actv, mapping=wires.s) reg_s.mref = np.zeros(3*nC) reg_s.cell_weights = (wires.s * wr) reg_t = Regularization.Sparse(mesh, indActive=actv, mapping=wires.t) reg_t.mref = np.zeros(3*nC) reg_t.cell_weights = (wires.t * wr) reg = reg_p + reg_s + reg_t reg.mref = np.zeros(3*nC) # Data misfit function dmis = DataMisfit.l2_DataMisfit(survey) dmis.W = 1./survey.std # Add directives to the inversion opt = Optimization.ProjectedGNCG(maxIter=30, lower=-10, upper=10., maxIterLS=20, maxIterCG=20, tolCG=1e-4) invProb = InvProblem.BaseInvProblem(dmis, reg, opt) # A list of directive to control the inverson betaest = Directives.BetaEstimate_ByEig() # Here is where the norms are applied # Use pick a treshold parameter empirically based on the distribution of # model parameters IRLS = Directives.Update_IRLS( f_min_change=1e-3, maxIRLSiter=0, beta_tol=5e-1 ) # Pre-conditioner update_Jacobi = Directives.UpdatePreconditioner() inv = Inversion.BaseInversion(invProb, directiveList=[IRLS, update_Jacobi, betaest]) # Run the inversion m0 = np.ones(3*nC) * 1e-4 # Starting model mrec_MVIC = inv.run(m0) self.mstart = Utils.matutils.cartesian2spherical(mrec_MVIC.reshape((nC, 3), order='F')) beta = invProb.beta dmis.prob.coordinate_system = 'spherical' dmis.prob.model = self.mstart # Create a block diagonal regularization wires = Maps.Wires(('amp', nC), ('theta', nC), ('phi', nC)) # Create a Combo Regularization # Regularize the amplitude of the vectors reg_a = Regularization.Sparse(mesh, indActive=actv, mapping=wires.amp) reg_a.norms = np.c_[0., 0., 0., 0.] # Sparse on the model and its gradients reg_a.mref = np.zeros(3*nC) # Regularize the vertical angle of the vectors reg_t = Regularization.Sparse(mesh, indActive=actv, mapping=wires.theta) reg_t.alpha_s = 0. # No reference angle reg_t.space = 'spherical' reg_t.norms = np.c_[2., 0., 0., 0.] # Only norm on gradients used # Regularize the horizontal angle of the vectors reg_p = Regularization.Sparse(mesh, indActive=actv, mapping=wires.phi) reg_p.alpha_s = 0. # No reference angle reg_p.space = 'spherical' reg_p.norms = np.c_[2., 0., 0., 0.] # Only norm on gradients used reg = reg_a + reg_t + reg_p reg.mref = np.zeros(3*nC) Lbound = np.kron(np.asarray([0, -np.inf, -np.inf]), np.ones(nC)) Ubound = np.kron(np.asarray([10, np.inf, np.inf]), np.ones(nC)) # Add directives to the inversion opt = Optimization.ProjectedGNCG(maxIter=20, lower=Lbound, upper=Ubound, maxIterLS=20, maxIterCG=30, tolCG=1e-3, stepOffBoundsFact=1e-3, ) opt.approxHinv = None invProb = InvProblem.BaseInvProblem(dmis, reg, opt, beta=beta*10.) # Here is where the norms are applied IRLS = Directives.Update_IRLS(f_min_change=1e-4, maxIRLSiter=20, minGNiter=1, beta_tol=0.5, coolingRate=1, coolEps_q=True, betaSearch=False) # Special directive specific to the mag amplitude problem. The sensitivity # weights are update between each iteration. ProjSpherical = Directives.ProjectSphericalBounds() update_SensWeight = Directives.UpdateSensitivityWeights() update_Jacobi = Directives.UpdatePreconditioner() self.inv = Inversion.BaseInversion( invProb, directiveList=[ ProjSpherical, IRLS, update_SensWeight, update_Jacobi ] )
def run_inversion_cg( self, maxIter=60, m0=0.0, mref=0.0, percentage=5, floor=0.1, chifact=1, beta0_ratio=1.0, coolingFactor=1, coolingRate=1, alpha_s=1.0, alpha_x=1.0, use_target=False, ): survey, prob = self.get_problem_survey() survey.eps = percentage survey.std = floor survey.dobs = self.data.copy() self.uncertainty = percentage * abs(survey.dobs) * 0.01 + floor m0 = np.ones(self.M) * m0 mref = np.ones(self.M) * mref reg = Regularization.Tikhonov( self.mesh, alpha_s=alpha_s, alpha_x=alpha_x, mref=mref ) dmis = DataMisfit.l2_DataMisfit(survey) dmis.W = 1.0 / self.uncertainty opt = Optimization.InexactGaussNewton(maxIter=maxIter, maxIterCG=20) opt.remember("xc") opt.tolG = 1e-10 opt.eps = 1e-10 invProb = InvProblem.BaseInvProblem(dmis, reg, opt) save = Directives.SaveOutputEveryIteration() beta_schedule = Directives.BetaSchedule( coolingFactor=coolingFactor, coolingRate=coolingRate ) target = Directives.TargetMisfit(chifact=chifact) if use_target: directives = [ Directives.BetaEstimate_ByEig(beta0_ratio=beta0_ratio), beta_schedule, target, save, ] else: directives = [ Directives.BetaEstimate_ByEig(beta0_ratio=beta0_ratio), beta_schedule, save, ] inv = Inversion.BaseInversion(invProb, directiveList=directives) mopt = inv.run(m0) model = opt.recall("xc") model.append(mopt) pred = [] for m in model: pred.append(survey.dpred(m)) return model, pred, save
m0 = np.median(ln_sigback) * np.ones(mapping.nP) dmis = DataMisfit.l2_DataMisfit(survey) regT = Regularization.Simple(mesh, indActive=actind) # Personal preference for this solver with a Jacobi preconditioner opt = Optimization.ProjectedGNCG(maxIter=20, lower=-10, upper=10, maxIterLS=20, maxIterCG=30, tolCG=1e-4) opt.remember('xc') invProb = InvProblem.BaseInvProblem(dmis, regT, opt) beta = Directives.BetaEstimate_ByEig(beta0_ratio=1.) Target = Directives.TargetMisfit() betaSched = Directives.BetaSchedule(coolingFactor=5., coolingRate=2) updateSensW = Directives.UpdateSensitivityWeights(threshold=1e-3) update_Jacobi = Directives.UpdatePreconditioner() inv = Inversion.BaseInversion( invProb, directiveList=[beta, Target, betaSched, updateSensW, update_Jacobi]) minv = inv.run(m0) # Final Plot ############ fig, ax = plt.subplots(1, 2, figsize=(12, 5))
def resolve_1Dinversions(mesh, dobs, src_height, freqs, m0, mref, mapping, std=0.08, floor=1e-14, rxOffset=7.86): """ Perform a single 1D inversion for a RESOLVE sounding for Horizontal Coplanar Coil data (both real and imaginary). :param discretize.CylMesh mesh: mesh used for the forward simulation :param numpy.array dobs: observed data :param float src_height: height of the source above the ground :param numpy.array freqs: frequencies :param numpy.array m0: starting model :param numpy.array mref: reference model :param Maps.IdentityMap mapping: mapping that maps the model to electrical conductivity :param float std: percent error used to construct the data misfit term :param float floor: noise floor used to construct the data misfit term :param float rxOffset: offset between source and receiver. """ # ------------------- Forward Simulation ------------------- # # set up the receivers bzr = EM.FDEM.Rx.Point_bSecondary(np.array([[rxOffset, 0., src_height]]), orientation='z', component='real') bzi = EM.FDEM.Rx.Point_b(np.array([[rxOffset, 0., src_height]]), orientation='z', component='imag') # source location srcLoc = np.array([0., 0., src_height]) srcList = [ EM.FDEM.Src.MagDipole([bzr, bzi], freq, srcLoc, orientation='Z') for freq in freqs ] # construct a forward simulation survey = EM.FDEM.Survey(srcList) prb = EM.FDEM.Problem3D_b(mesh, sigmaMap=mapping, Solver=PardisoSolver) prb.pair(survey) # ------------------- Inversion ------------------- # # data misfit term survey.dobs = dobs dmisfit = DataMisfit.l2_DataMisfit(survey) uncert = abs(dobs) * std + floor dmisfit.W = 1. / uncert # regularization regMesh = Mesh.TensorMesh([mesh.hz[mapping.maps[-1].indActive]]) reg = Regularization.Simple(regMesh) reg.mref = mref # optimization opt = Optimization.InexactGaussNewton(maxIter=10) # statement of the inverse problem invProb = InvProblem.BaseInvProblem(dmisfit, reg, opt) # Inversion directives and parameters target = Directives.TargetMisfit() inv = Inversion.BaseInversion(invProb, directiveList=[target]) invProb.beta = 2. # Fix beta in the nonlinear iterations reg.alpha_s = 1e-3 reg.alpha_x = 1. prb.counter = opt.counter = Utils.Counter() opt.LSshorten = 0.5 opt.remember('xc') # run the inversion mopt = inv.run(m0) return mopt, invProb.dpred, survey.dobs
reg = Regularization.Sparse(mesh, indActive=actv, mapping=Maps.IdentityMap(nP=nC)) reg.cell_weights = wrGlobal reg.norms = np.c_[driver.lpnorms].T reg.mref = mref # Add directives to the inversion opt = Optimization.ProjectedGNCG(maxIter=100, lower=-10., upper=10., maxIterCG=20, tolCG=1e-3) invProb = InvProblem.BaseInvProblem(ComboMisfit, reg, opt) betaest = Directives.BetaEstimate_ByEig() # Here is where the norms are applied IRLS = Directives.Update_IRLS(f_min_change=1e-3, minGNiter=1) update_Jacobi = Directives.UpdateJacobiPrecond() targetMisfit = Directives.TargetMisfit() saveModel = Directives.SaveUBCModelEveryIteration(mapping=actvMap) saveModel.fileName = work_dir + out_dir + 'GRAV' inv = Inversion.BaseInversion( invProb, directiveList=[betaest, IRLS, update_Jacobi, saveModel]) mrec = inv.run(mstart) if isinstance(mesh, Mesh.TreeMesh):