Files
simpeg/SimPEG/Examples/Linear.py
T
2014-05-18 10:57:06 -07:00

79 lines
1.9 KiB
Python

from SimPEG import *
class LinearSurvey(Survey.BaseSurvey):
def projectFields(self, u):
return u
class LinearProblem(Problem.BaseProblem):
"""docstring for LinearProblem"""
surveyPair = LinearSurvey
def __init__(self, model, G, **kwargs):
Problem.BaseProblem.__init__(self, model, **kwargs)
self.G = G
def fields(self, m, u=None):
return self.G.dot(m)
def Jvec(self, m, v, u=None):
return self.G.dot(v)
def Jtvec(self, m, v, u=None):
return self.G.T.dot(v)
def run(N, plotIt=True):
mesh = Mesh.TensorMesh([N])
nk = 20
jk = np.linspace(1.,20.,nk)
p = -0.25
q = 0.25
g = lambda k: np.exp(p*jk[k]*mesh.vectorCCx)*np.cos(2*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 = LinearProblem(mesh, G)
survey = LinearSurvey()
survey.pair(prob)
survey.makeSyntheticData(mtrue, std=0.01)
M = prob.mesh
reg = Regularization.Tikhonov(mesh)
dmis = DataMisfit.l2_DataMisfit(survey)
opt = Optimization.InexactGaussNewton(maxIter=20)
invProb = InvProblem.BaseInvProblem(dmis, reg, opt)
beta = Directives.BetaSchedule()
betaest = Directives.BetaEstimate_ByEig()
inv = Inversion.BaseInversion(invProb, directiveList=[beta, betaest])
m0 = np.zeros_like(survey.mtrue)
mrec = inv.run(m0)
if plotIt:
import matplotlib.pyplot as plt
plt.figure(1)
for i in range(prob.G.shape[0]):
plt.plot(prob.G[i,:])
plt.figure(2)
plt.plot(M.vectorCCx, survey.mtrue, 'b-')
plt.plot(M.vectorCCx, mrec, 'r-')
plt.show()
return prob, survey, mesh, mrec
if __name__ == '__main__':
run(100)