Fixes to ModelBuilder. Start of the DCProblem.

2026-07-11 08:50:14 +08:00 · 2013-10-02 15:24:51 -07:00
parent 7a4ccc9a38
commit d8c676015e
6 changed files with 224 additions and 36 deletions
@@ -0,0 +1,93 @@
+from SimPEG import TensorMesh
+from SimPEG.forward import Problem, SyntheticProblem
+from SimPEG.utils import ModelBuilder
+import numpy as np
+import scipy.sparse.linalg as linalg
+import DCutils
+
+class DCProblem(Problem):
+    """docstring for DCProblem"""
+    def __init__(self, mesh):
+        super(DCProblem, self).__init__(mesh)
+        self.mesh.setCellGradBC('neumann')
+
+    def createMatrix(self, m):
+        D = self.mesh.faceDiv
+        G = self.mesh.cellGrad
+        sigma = self.modelTransform(m)
+        Msig = self.mesh.getFaceMass(sigma)
+        A = D*Msig*G
+        return A.tocsc()
+
+    def field(self, m):
+        A = self.createMatrix(m)
+        solve = linalg.factorized(A)
+
+        nRHSs = self.RHS.shape[1]  # Number of RHSs
+        phi = np.zeros((self.mesh.nC, nRHSs)) + np.nan
+        for ii in range(nRHSs):
+            phi[:,ii] = solve(self.RHS[:,ii])
+
+        return phi
+
+    def J(self, m, v, u=None, RHSii=0, solve=None):
+        P = self.P
+        D = self.mesh.faceDiv
+        G = self.mesh.cellGrad
+        A = self.createMatrix(m)
+        Av_dm = self.mesh.getFaceMassDeriv()
+        mT_dm = self.modelTransform(m)
+
+        dCdu = A
+        dCdm = - D * ( sdiag( G * u[:, RHSii] ) * ( Av_dm * ( mT_dm * v ) ) )
+
+        if solve is None:
+            solve = linalg.factorized(dCdu)
+
+        return - P * solve(dCdm)
+
+
+
+if __name__ == '__main__':
+    # Create the mesh
+    h1 = np.ones(100)
+    h2 = np.ones(100)
+    mesh = TensorMesh([h1,h2])
+
+    # Create some parameters for the model
+    sig1 = 1
+    sig2 = 0.01
+
+    # Create a synthetic model from a block in a half-space
+    p0 = [20, 20]
+    p1 = [50, 50]
+    condVals = [sig1, sig2]
+    mSynth = ModelBuilder.defineBlockConductivity(p0,p1,mesh.gridCC,condVals)
+    mesh.plotImage(mSynth, showIt=False)
+
+
+    # Set up the projection
+    nelec = 50
+    spacelec = 2
+    surfloc = 0.5
+    elecini = 0.5
+    elecend = 0.5+spacelec*(nelec-1)
+    elecLocR = np.linspace(elecini, elecend, nelec)
+    rxmidLoc = (elecLocR[0:nelec-1]+elecLocR[1:nelec])*0.5
+    q, Q, rxmidloc = DCutils.genTxRxmat(nelec, spacelec, surfloc, elecini, mesh)
+
+
+    # Create some data
+    class syntheticDCProblem(DCProblem, SyntheticProblem):
+        pass
+
+    synthetic = syntheticDCProblem(mesh);
+    synthetic.P = Q.T
+    synthetic.RHS = q
+    dobs, Wd = synthetic.createData(mSynth)
+
+    # Now set up the problem to do some minimization
+    problem = DCProblem(mesh)
+
+
+