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removed DC_PseudoSection_Simulation, it still exsists on the examples branch and on dcip/dev
This commit is contained in:
Lindsey Heagy
@@ -1,220 +0,0 @@
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from SimPEG import *
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# import simpegDCIP as DC
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from SimPEG import DCIP as DC
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import scipy.interpolate as interpolation
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import matplotlib.pyplot as plt
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import time
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import re
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def run(loc=np.c_[[-50.,0.,-50.],[50.,0.,-50.]], sig=np.r_[1e-2,1e-1,1e-3], radi=np.r_[25.,25.], param = np.r_[30.,30.,5], stype = 'dpdp', plotIt=True):
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"""
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DC Forward Simulation
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=====================
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Forward model conductive spheres in a half-space and plot a pseudo-section
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Created on Mon Feb 01 19:28:06 2016
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@fourndo
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"""
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def getIndicesSphere(center,radius,ccMesh):
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"""
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Creates a vector containing the sphere indices in the cell centers mesh.
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Returns a tuple
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The sphere is defined by the points
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p0, describe the position of the center of the cell
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r, describe the radius of the sphere.
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ccMesh represents the cell-centered mesh
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The points p0 must live in the the same dimensional space as the mesh.
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"""
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# Validation: mesh and point (p0) live in the same dimensional space
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dimMesh = np.size(ccMesh[0,:])
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assert len(center) == dimMesh, "Dimension mismatch. len(p0) != dimMesh"
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if dimMesh == 1:
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# Define the reference points
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ind = np.abs(center[0] - ccMesh[:,0]) < radius
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elif dimMesh == 2:
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# Define the reference points
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ind = np.sqrt( ( center[0] - ccMesh[:,0] )**2 + ( center[1] - ccMesh[:,1] )**2 ) < radius
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elif dimMesh == 3:
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# Define the points
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ind = np.sqrt( ( center[0] - ccMesh[:,0] )**2 + ( center[1] - ccMesh[:,1] )**2 + ( center[2] - ccMesh[:,2] )**2 ) < radius
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# Return a tuple
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return ind
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# First we need to create a mesh and a model.
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# This is our mesh
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dx = 5.
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hxind = [(dx,15,-1.3), (dx, 75), (dx,15,1.3)]
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hyind = [(dx,15,-1.3), (dx, 10), (dx,15,1.3)]
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hzind = [(dx,15,-1.3),(dx, 15)]
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mesh = Mesh.TensorMesh([hxind, hyind, hzind], 'CCN')
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# Set background conductivity
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model = np.ones(mesh.nC) * sig[0]
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# First anomaly
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ind = getIndicesSphere(loc[:,0],radi[0],mesh.gridCC)
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model[ind] = sig[1]
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# Second anomaly
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ind = getIndicesSphere(loc[:,1],radi[1],mesh.gridCC)
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model[ind] = sig[2]
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# Get index of the center
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indy = int(mesh.nCy/2)
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# Plot the model for reference
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# Define core mesh extent
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xlim = 200
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zlim = 125
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# Specify the survey type: "pdp" | "dpdp"
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# Then specify the end points of the survey. Let's keep it simple for now and survey above the anomalies, top of the mesh
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ends = [(-175,0),(175,0)]
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ends = np.c_[np.asarray(ends),np.ones(2).T*mesh.vectorNz[-1]]
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# Snap the endpoints to the grid. Easier to create 2D section.
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indx = Utils.closestPoints(mesh, ends )
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locs = np.c_[mesh.gridCC[indx,0],mesh.gridCC[indx,1],np.ones(2).T*mesh.vectorNz[-1]]
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# We will handle the geometry of the survey for you and create all the combination of tx-rx along line
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[Tx, Rx] = DC.gen_DCIPsurvey(locs, mesh, stype, param[0], param[1], param[2])
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# Define some global geometry
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dl_len = np.sqrt( np.sum((locs[0,:] - locs[1,:])**2) )
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dl_x = ( Tx[-1][0,1] - Tx[0][0,0] ) / dl_len
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dl_y = ( Tx[-1][1,1] - Tx[0][1,0] ) / dl_len
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azm = np.arctan(dl_y/dl_x)
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#Set boundary conditions
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mesh.setCellGradBC('neumann')
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# Define the differential operators needed for the DC problem
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Div = mesh.faceDiv
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Grad = mesh.cellGrad
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Msig = Utils.sdiag(1./(mesh.aveF2CC.T*(1./model)))
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A = Div*Msig*Grad
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# Change one corner to deal with nullspace
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A[0,0] = 1
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A = sp.csc_matrix(A)
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# We will solve the system iteratively, so a pre-conditioner is helpful
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# This is simply a Jacobi preconditioner (inverse of the main diagonal)
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dA = A.diagonal()
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P = sp.spdiags(1/dA,0,A.shape[0],A.shape[0])
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# Now we can solve the system for all the transmitters
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# We want to store the data
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data = []
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# There is probably a more elegant way to do this, but we can just for-loop through the transmitters
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for ii in range(len(Tx)):
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start_time = time.time() # Let's time the calculations
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#print("Transmitter %i / %i\r" % (ii+1,len(Tx)))
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# Select dipole locations for receiver
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rxloc_M = np.asarray(Rx[ii][:,0:3])
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rxloc_N = np.asarray(Rx[ii][:,3:])
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# For usual cases "dpdp" or "gradient"
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if not re.match(stype,'pdp'):
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inds = Utils.closestPoints(mesh, np.asarray(Tx[ii]).T )
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RHS = mesh.getInterpolationMat(np.asarray(Tx[ii]).T, 'CC').T*( [-1,1] / mesh.vol[inds] )
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else:
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# Create an "inifinity" pole
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tx = np.squeeze(Tx[ii][:,0:1])
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tinf = tx + np.array([dl_x,dl_y,0])*dl_len*2
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inds = Utils.closestPoints(mesh, np.c_[tx,tinf].T)
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RHS = mesh.getInterpolationMat(np.asarray(Tx[ii]).T, 'CC').T*( [-1] / mesh.vol[inds] )
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# Iterative Solve
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Ainvb = sp.linalg.bicgstab(P*A,P*RHS, tol=1e-5)
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# We now have the potential everywhere
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phi = mkvc(Ainvb[0])
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# Solve for phi on pole locations
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P1 = mesh.getInterpolationMat(rxloc_M, 'CC')
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P2 = mesh.getInterpolationMat(rxloc_N, 'CC')
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# Compute the potential difference
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dtemp = (P1*phi - P2*phi)*np.pi
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data.append( dtemp )
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print '\rTransmitter {0} of {1} -> Time:{2} sec'.format(ii,len(Tx),time.time()- start_time),
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print 'Transmitter {0} of {1}'.format(ii,len(Tx))
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print 'Forward completed'
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# Let's just convert the 3D format into 2D (distance along line) and plot
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[Tx2d, Rx2d] = DC.convertObs_DC3D_to_2D(Tx,Rx)
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# Here is an example for the first tx-rx array
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if plotIt:
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fig = plt.figure()
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ax = plt.subplot(2,1,1, aspect='equal')
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mesh.plotSlice(np.log10(model), ax =ax, normal = 'Y', ind = indy,grid=True)
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ax.set_title('E-W section at '+str(mesh.vectorCCy[indy])+' m')
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plt.gca().set_aspect('equal', adjustable='box')
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plt.scatter(Tx[0][0,:],Tx[0][2,:],s=40,c='g', marker='v')
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plt.scatter(Rx[0][:,0::3],Rx[0][:,2::3],s=40,c='y')
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plt.xlim([-xlim,xlim])
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plt.ylim([-zlim,mesh.vectorNz[-1]+dx])
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ax = plt.subplot(2,1,2, aspect='equal')
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# Plot the location of the spheres for reference
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circle1=plt.Circle((loc[0,0]-Tx[0][0,0],loc[2,0]),radi[0],color='w',fill=False, lw=3)
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circle2=plt.Circle((loc[0,1]-Tx[0][0,0],loc[2,1]),radi[1],color='k',fill=False, lw=3)
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ax.add_artist(circle1)
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ax.add_artist(circle2)
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# Add the speudo section
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DC.plot_pseudoSection(Tx2d,Rx2d,data,mesh.vectorNz[-1],stype)
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plt.scatter(Tx2d[0][:],Tx[0][2,:],s=40,c='g', marker='v')
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plt.scatter(Rx2d[0][:],Rx[0][:,2::3],s=40,c='y')
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plt.plot(np.r_[Tx2d[0][0],Rx2d[-1][-1,-1]],np.ones(2)*mesh.vectorNz[-1], color='k')
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plt.ylim([-zlim,mesh.vectorNz[-1]+dx])
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plt.show()
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return fig, ax
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if __name__ == '__main__':
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run()
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