Source code for pygimli.physics.ert.ertManager

#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""Method Manager for Electrical Resistivity Tomography (ERT)"""

import os.path
import numpy as np

import pygimli as pg
from pygimli.frameworks import MeshMethodManager
from .ertModelling import ERTModelling, ERTModellingReference
from .ert import createInversionMesh, estimateError
from pygimli.utils import getSavePath


[docs]class ERTManager(MeshMethodManager): """ERT Manager. Method Manager for Electrical Resistivity Tomography (ERT) Todo ---- * 3d * 3dtopo * complex on/off * closed geometry * transdim * singularity removal * ERT specific inversion options: * ... """
[docs] def __init__(self, data=None, **kwargs): """Create ERT Manager instance. Parameters ---------- data: :gimliapi:`GIMLI::DataContainerERT` | str You can initialize the Manager with data or give them a dataset when calling the inversion. Other Parameters ---------------- * useBert: bool [True] Use Bert forward operator instead of the reference implementation. * sr: bool [True] Calculate with singularity removal technique. Recommended but needs the primary potential. For flat earth cases the primary potential will be calculated analytical. For domains with topography the primary potential will be calculated numerical using a p2 refined mesh or you provide primary potentials with setPrimPot. """ self.useBert = kwargs.pop('useBert', True) self.sr = kwargs.pop('sr', True) super().__init__(data=data, **kwargs) self.inv.dataTrans = pg.trans.TransLogLU()
[docs] def setSingularityRemoval(self, sr=True): """Turn singularity removal on or off.""" self.reinitForwardOperator(sr=True)
[docs] def createForwardOperator(self, **kwargs): """Create and choose forward operator.""" verbose = kwargs.pop('verbose', False) self.useBert = kwargs.pop('useBert', self.useBert) self.sr = kwargs.pop('sr', self.sr) if self.useBert: pg.verbose('Create ERTModelling FOP') fop = ERTModelling(sr=self.sr, verbose=verbose) else: pg.verbose('Create ERTModellingReference FOP') fop = ERTModellingReference(**kwargs) return fop
[docs] def load(self, fileName): """Load ERT data. Forwarded to :py:mod:`pygimli.physics.ert.load` Parameters ---------- fileName: str Filename for the data. Returns ------- data: :gimliapi:`GIMLI::DataContainerERT` """ self.data = pg.physics.ert.load(fileName) return self.data
[docs] def createMesh(self, data=None, **kwargs): """Create default inversion mesh. Forwarded to :py:mod:`pygimli.physics.ert.createInversionMesh` """ d = data or self.data if d is None: pg.critical('Please provide a data file for mesh generation') return createInversionMesh(d, **kwargs)
[docs] def setPrimPot(self, pot): """Set primary potential from external is not supported anymore.""" pg.critical("Not implemented.")
[docs] def simulate(self, mesh, scheme, res, **kwargs): """Simulate an ERT measurement. Perform the forward task for a given mesh, resistivity distribution & measuring scheme and return data (apparent resistivity) or potentials. For complex resistivity, the apparent resistivities is complex as well. The forward operator itself only calculates potential values for the electrodes in the given data scheme. To calculate apparent resistivities, geometric factors (k) are needed. If there are no values k in the DataContainerERT scheme, the function tries to calculate them, either analytically or numerically by using a p2-refined version of the given mesh. TODO ---- * 2D + Complex + SR Args ---- mesh : :gimliapi:`GIMLI::Mesh` 2D or 3D Mesh to calculate for. res : float, array(mesh.cellCount()) | array(N, mesh.cellCount()) | list Resistivity distribution for the given mesh cells can be: . float for homogeneous resistivity (e.g. 1.0) . single array of length mesh.cellCount() . matrix of N resistivity distributions of length mesh.cellCount() . resistivity map as [[regionMarker0, res0], [regionMarker0, res1], ...] scheme : :gimliapi:`GIMLI::DataContainerERT` Data measurement scheme. Keyword Args ------------ verbose: bool[False] Be verbose. Will override class settings. calcOnly: bool [False] Use fop.calculate instead of fop.response. Useful if you want to force the calculation of impedances for homogeneous models. No noise handling. Solution is put as token 'u' in the returned DataContainerERT. noiseLevel: float [0.0] add normally distributed noise based on scheme['err'] or on noiseLevel if error>0 is not contained noiseAbs: float [0.0] Absolute voltage error in V returnArray: bool [False] Returns an array of apparent resistivities instead of a DataContainerERT returnFields: bool [False] Returns a matrix of all potential values (per mesh nodes) for each injection electrodes. Returns ------- DataContainerERT | array(data.size()) | array(N, data.size()) | array(N, mesh.nodeCount()): Data container with resulting apparent resistivity data and errors (if noiseLevel or noiseAbs is set). Optional returns a Matrix of rhoa values (for returnArray==True forces noiseLevel=0). In case of a complex valued resistivity model, phase values are returned in the DataContainerERT (see example below), or as an additionally returned array. Examples -------- # >>> from pygimli.physics import ert # >>> import pygimli as pg # >>> import pygimli.meshtools as mt # >>> world = mt.createWorld(start=[-50, 0], end=[50, -50], # ... layers=[-1, -5], worldMarker=True) # >>> scheme = ert.createData( # ... elecs=pg.utils.grange(start=-10, end=10, n=21), # ... schemeName='dd') # >>> for pos in scheme.sensorPositions(): # ... _= world.createNode(pos) # ... _= world.createNode(pos + [0.0, -0.1]) # >>> mesh = mt.createMesh(world, quality=34) # >>> rhomap = [ # ... [1, 100. + 0j], # ... [2, 50. + 0j], # ... [3, 10.+ 0j], # ... ] # >>> data = ert.simulate(mesh, res=rhomap, scheme=scheme, verbose=1) # >>> rhoa = data.get('rhoa').array() # >>> phia = data.get('phia').array() """ pg.warn('Obsolete, do not use!. Use ert.simulate instead') verbose = kwargs.pop('verbose', self.verbose) calcOnly = kwargs.pop('calcOnly', False) returnFields = kwargs.pop("returnFields", False) returnArray = kwargs.pop('returnArray', False) noiseLevel = kwargs.pop('noiseLevel', 0.0) noiseAbs = kwargs.pop('noiseAbs', 1e-4) seed = kwargs.pop('seed', None) sr = kwargs.pop('sr', self.sr) # segfaults with self.fop (test & fix) fop = self.createForwardOperator(useBert=self.useBert, sr=sr, verbose=verbose) fop.data = scheme fop.setMesh(mesh, ignoreRegionManager=True) rhoa = None phia = None isArrayData = False # parse the given res into mesh-cell-sized array if isinstance(res, int) or isinstance(res, float): res = np.ones(mesh.cellCount()) * float(res) elif isinstance(res, complex): res = np.ones(mesh.cellCount()) * res elif hasattr(res[0], '__iter__'): # ndim == 2 if len(res[0]) == 2: # res seems to be a res map # check if there are markers in the mesh that are not defined # the rhomap. better signal here before it results in errors meshMarkers = list(set(mesh.cellMarkers())) mapMarkers = [m[0] for m in res] if any([mark not in mapMarkers for mark in meshMarkers]): left = [m for m in meshMarkers if m not in mapMarkers] pg.critical("Mesh contains markers without assigned " "resistivities {}. Please fix given " "rhomap.".format(left)) res = pg.solver.parseArgToArray(res, mesh.cellCount(), mesh) else: # probably nData x nCells array # better check for array data here isArrayData = True if isinstance(res[0], np.complex) or isinstance(res, pg.CVector): pg.info("Complex resistivity values found.") fop.setComplex(True) else: fop.setComplex(False) if not scheme.allNonZero('k') and not calcOnly: if verbose: pg.info('Calculate geometric factors.') scheme.set('k', fop.calcGeometricFactor(scheme)) ret = pg.DataContainerERT(scheme) # just to be sure that we don't work with artifacts ret['u'] *= 0.0 ret['i'] *= 0.0 ret['r'] *= 0.0 if isArrayData: rhoa = np.zeros((len(res), scheme.size())) for i, r in enumerate(res): rhoa[i] = fop.response(r) if verbose: print(i, "/", len(res), " : ", pg.dur(), "s", "min r:", min(r), "max r:", max(r), "min r_a:", min(rhoa[i]), "max r_a:", max(rhoa[i])) else: # res is single resistivity array if len(res) == mesh.cellCount(): if calcOnly: fop.mapERTModel(res, 0) dMap = pg.core.DataMap() fop.calculate(dMap) if fop.complex(): pg.critical('Implement me') else: ret["u"] = dMap.data(scheme) ret["i"] = np.ones(ret.size()) if returnFields: return pg.Matrix(fop.solution()) return ret else: if fop.complex(): res = pg.utils.squeezeComplex(res) resp = fop.response(res) if fop.complex(): rhoa, phia = pg.utils.toPolar(resp) else: rhoa = resp else: print(mesh) print("res: ", res) raise BaseException( "Simulate called with wrong resistivity array.") if not isArrayData: ret['rhoa'] = rhoa if phia is not None: ret.set('phia', phia) else: ret.set('rhoa', rhoa[0]) if phia is not None: ret.set('phia', phia[0]) if returnFields: return pg.Matrix(fop.solution()) if noiseLevel > 0: # if errors in data noiseLevel=1 just triggers if not ret.allNonZero('err'): # 1A and #100┬ÁV ret.set('err', self.estimateError(ret, relativeError=noiseLevel, absoluteUError=noiseAbs, absoluteCurrent=1)) print("Data error estimate (min:max) ", min(ret('err')), ":", max(ret('err'))) rhoa *= 1. + pg.randn(ret.size(), seed=seed) * ret('err') ret.set('rhoa', rhoa) ipError = None if phia is not None: if scheme.allNonZero('iperr'): ipError = scheme('iperr') else: # np.abs(self.data("phia") +TOLERANCE) * 1e-4absoluteError if noiseLevel > 0.5: noiseLevel /= 100. if 'phiErr' in kwargs: ipError = np.ones(ret.size()) * kwargs.pop('phiErr') \ / 1000 else: ipError = abs(ret["phia"]) * noiseLevel if verbose: print("Data IP abs error estimate (min:max) ", min(ipError), ":", max(ipError)) phia += pg.randn(ret.size(), seed=seed) * ipError ret['iperr'] = ipError ret['phia'] = phia # check what needs to be setup and returned if returnArray: if phia is not None: return rhoa, phia else: return rhoa return ret
[docs] def checkData(self, data=None): """Return data from container. THINKABOUT: Data will be changed, or should the manager keep a copy? """ data = data or pg.DataContainerERT(self.data) # topo = min(pg.z(data)) != max(pg.z(data)) # not used!! if isinstance(data, pg.DataContainer): if not data.allNonZero('k'): pg.critical("Data contains no geometric factors data['k'].") # numeric = min(pg.z(data)) != max(pg.z(data)) # data['k'] = createGeometricFactors(data, # numerical=topo, # #p2=True, # verbose=self.verbose) if self.fop.complex(): if not data.haveData('rhoa'): pg.critical('Datacontainer have no "rhoa" values.') if not data.haveData('ip'): pg.critical('Datacontainer have no "ip" values.') # pg.warn('check sign of phases') rhoa = data['rhoa'] phia = -data['ip']/1000 # 'ip' is defined for neg mrad. # we should think about some 'phia' in rad return pg.utils.squeezeComplex(pg.utils.toComplex(rhoa, phia)) else: if not data.haveData('rhoa'): if data.allNonZero('r'): pg.info("Creating apparent resistivies from " "impedences rhoa = r * k") data['rhoa'] = data['r'] * data['k'] elif data.allNonZero('u') and data.allNonZero('i'): pg.info("Creating apparent resistivies from " "voltage and currrent rhoa = u/i * k") data['rhoa'] = data['u']/data['i'] * data['k'] else: pg.critical("Datacontainer have neither: " "apparent resistivies 'rhoa', " "or impedances 'r', " "or voltage 'u' along with current 'i'.") if any(data['rhoa'] < 0) and \ isinstance(self.inv.dataTrans, pg.core.TransLog): # print(pg.find(data['rhoa'] < 0)) # print(data['rhoa'][data['rhoa'] < 0]) pg.warning("Found negative apparent resistivities. " "These can't be processed with logarithmic " "data transformation. You should consider to " "filter them out using " "data.remove(data['rhoa'] < 0).") return data['rhoa'] return data
[docs] def checkErrors(self, err, dataVals): """Check (estimate) and return relative error. By default we assume 'err' are relative values. """ if isinstance(err, pg.DataContainer): rae = None if not err.allNonZero('err'): pg.warn("Datacontainer have no 'err' values. " "Fallback of 1mV + 3% using " "ERTManager.estimateError(...) ") rae = self.estimateError(err, absoluteError=0.001, relativeError=0.03) else: rae = err['err'] if self.fop.complex(): ipe = None if err.haveData('iperr'): amp, phi = pg.utils.toPolar(dataVals) # assuming ipErr are absolute dPhi in mrad ipe = err['iperr'] / abs((phi*1000)) else: pg.warn("Datacontainer have no 'iperr' values. " "Fallback set to 0.01") ipe = np.ones(err.size()) * 0.01 return pg.cat(rae, ipe) return rae # not set if err is no DataContainer (else missing)
[docs] def estimateError(self, data=None, **kwargs): """Estimate error composed of an absolute and a relative part. Parameters ---------- absoluteError : float [0.001] Absolute data error in Ohm m. Need 'rhoa' values in data. relativeError : float [0.03] relative error level in %/100 absoluteUError : float [0.001] Absolute potential error in V. Need 'u' values in data. Or calculate them from 'rhoa', 'k' and absoluteCurrent if no 'i' is given absoluteCurrent : float [0.1] Current level in A for reconstruction for absolute potential V Returns ------- error : Array """ if data is None: # error = estimateError(self.data, **kwargs) self.data["err"] = error else: # the old way: better use ert.estimateError directly error = estimateError(data, **kwargs) return error
[docs] def coverage(self): """Coverage vector considering the logarithmic transformation.""" covTrans = pg.core.coverageDCtrans(self.fop.jacobian(), 1.0 / self.inv.response, 1.0 / self.inv.model) paramSizes = np.zeros(len(self.inv.model)) for c in self.fop.paraDomain.cells(): paramSizes[c.marker()] += c.size() return np.log10(covTrans / paramSizes)
[docs] def standardizedCoverage(self, threshold=0.01): """Return standardized coverage vector (0|1) using thresholding.""" return 1.0*(self.coverage() > threshold)
[docs] def showMisfit(self, errorWeighted=False, **kwargs): """Show relative or error-weighted data misfit.""" if errorWeighted: misfit = (np.log(self.data["rhoa"]) - np.log(self.inv.response)) /\ self.data["err"] kwargs.setdefault("label", "error-weighted misfit") else: misfit = - self.inv.response / self.data["rhoa"] * 100 + 100 kwargs.setdefault("label", "relative misfit (%)") kwargs.setdefault("cMax", np.max(misfit)) kwargs.setdefault("cMin", -kwargs["cMax"]) kwargs.setdefault("cMap", "bwr") kwargs.setdefault("logScale", False) self.showData(vals=misfit, **kwargs)
[docs] def showModel(self, model=None, elecs=True, ax=None, **kwargs): """Show the last inversion result. Parameters ---------- ax : mpl axes Axes object to draw into. Create a new if its not given. model : iterable [None] Model values to be draw. Default is self.model from the last run Returns ------- ax, cbar """ if model is None: model = self.model if ax is None: fig, ax = pg.plt.subplots() kwargs.setdefault("coverage", self.coverage()) ax, cBar = self.fop.drawModel(ax, model, **kwargs) if elecs is True: pg.viewer.mpl.drawSensors(ax, self.fop.data.sensors()) return ax, cBar
[docs] def saveResult(self, folder=None, size=(16, 10), **kwargs): """Save all results in the specified folder. Saved items are: Inverted profile Resistivity vector Coverage vector Standardized coverage vector Mesh (bms and vtk with results) """ subfolder = self.__class__.__name__ path = getSavePath(folder, subfolder) pg.info('Saving inversion results to: {}'.format(path)) np.savetxt(path + '/resistivity.vector', self.model) np.savetxt(path + '/resistivity-cov.vector', self.coverage()) np.savetxt(path + '/resistivity-scov.vector', self.standardizedCoverage()) self.fop.data.save(os.path.join(path, 'data.dat'), 'a b m n rhoa k err ip iperr') self.mesh.save(os.path.join(path, 'mesh')) m = pg.Mesh(self.paraDomain) m['Resistivity'] = self.paraModel(self.model) m['Resistivity (log10)'] = np.log10(m['Resistivity']) m['Coverage'] = self.coverage() m['S_Coverage'] = self.standardizedCoverage() m.exportVTK(os.path.join(path, 'resistivity')) m.saveBinaryV2(os.path.join(path, 'resistivity-pd')) self.fop.mesh().save(os.path.join(path, 'resistivity-mesh')) if self.paraDomain.dim() == 2: fig, ax = pg.plt.subplots(figsize=size) self.showModel(ax=ax, **kwargs) fig.savefig(path + '/resistivity.pdf', bbox_inches="tight") return path, fig, ax return path
if __name__ == "__main__": pass