mirror of
https://github.com/wassname/simpeg.git
synced 2026-07-07 13:37:49 +08:00
Gudni Karl Rosenkjaer
@@ -2,19 +2,27 @@ from SimPEG import Mesh, Utils, np, sp
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import SimPEG.DCIP as DC
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import time
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def run(loc=None, sig=None, radi=None, param=None, stype='dpdp', plotIt=True):
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def run(loc=None, sig=None, radi=None, param=None, stype='dpdp', dtype='appc', 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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Forward model two conductive spheres in a half-space and plot a
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pseudo-section. Assumes an infinite line source and measures along the
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center of the spheres.
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Created by @fourndo on Mon Feb 01 19:28:06 2016
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INPUT:
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loc = Location of spheres [[x1,y1,z1],[x2,y2,z2]]
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radi = Radius of spheres [r1,r2]
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param = Conductivity of background and two spheres [m0,m1,m2]
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stype = survey type "pdp" (pole dipole) or "dpdp" (dipole dipole)
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dtype = Data type "appr" (app res) | "appc" (app cond) | "volt" (potential)
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Created by @fourndo
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"""
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assert stype in ['pdp', 'dpdp'], "Source type (stype) must be pdp or dpdp (pole dipole or dipole dipole)"
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assert dtype in ['appr', 'appc', 'volt'], "Data type (dtype) must be appr (app res) or appc (app cond) or volt (potential)"
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if loc is None:
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loc = np.c_[[-50.,0.,-50.],[50.,0.,-50.]]
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@@ -27,7 +35,6 @@ def run(loc=None, sig=None, radi=None, param=None, stype='dpdp', plotIt=True):
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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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@@ -52,14 +59,10 @@ def run(loc=None, sig=None, radi=None, param=None, stype='dpdp', plotIt=True):
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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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zlim = 100
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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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@@ -77,12 +80,13 @@ def run(loc=None, sig=None, radi=None, param=None, stype='dpdp', plotIt=True):
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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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#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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# Define the linear system needed for the DC problem. We assume an infitite
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# line source for simplicity.
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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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@@ -145,16 +149,23 @@ def run(loc=None, sig=None, radi=None, param=None, stype='dpdp', plotIt=True):
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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(survey, np.ones(survey.nSrc))
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survey2D = DC.convertObs_DC3D_to_2D(survey, np.ones(survey.nSrc))
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survey2D = DC.convertObs_DC3D_to_2D(survey, np.ones(survey.nSrc) , 'Xloc')
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survey2D.dobs =np.hstack(data)
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# Here is an example for the first tx-rx array
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if plotIt:
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import matplotlib.pyplot as plt
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fig = plt.figure()
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fig = plt.figure(figsize=(7,7))
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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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# Plot the location of the spheres for reference
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circle1=plt.Circle((loc[0,0],loc[2,0]),radi[0],color='w',fill=False, lw=3)
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circle2=plt.Circle((loc[0,1],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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dat = mesh.plotSlice(np.log10(model), ax =ax, normal = 'Y',
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ind = indy,grid=True, clim = np.log10([sig.min(),sig.max()]))
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ax.set_title('3-D model')
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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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@@ -163,22 +174,34 @@ def run(loc=None, sig=None, radi=None, param=None, stype='dpdp', plotIt=True):
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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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pos = ax.get_position()
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ax.set_position([pos.x0 , pos.y0 + 0.025 , pos.width, pos.height])
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pos = ax.get_position()
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cbarax = fig.add_axes([pos.x0 , pos.y0 + 0.025 , pos.width, pos.height * 0.04]) ## the parameters are the specified position you set
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cb = fig.colorbar(dat[0],cax=cbarax, orientation="horizontal",
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ax = ax, ticks=np.linspace(np.log10(sig.min()),
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np.log10(sig.max()), 3), format="$10^{%.1f}$")
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cb.set_label("Conductivity (S/m)",size=12)
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cb.ax.tick_params(labelsize=12)
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# Second plot for the predicted apparent resistivity data
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ax2 = 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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circle1=plt.Circle((loc[0,0],loc[2,0]),radi[0],color='w',fill=False, lw=3)
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circle2=plt.Circle((loc[0,1],loc[2,1]),radi[1],color='k',fill=False, lw=3)
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ax2.add_artist(circle1)
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ax2.add_artist(circle2)
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# Add the speudo section
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DC.plot_pseudoSection(survey2D,ax,stype)
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dat = DC.plot_pseudoSection(survey2D,ax2,stype=stype, dtype = dtype)
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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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ax2.set_title('Apparent Conductivity data')
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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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@@ -42,17 +42,16 @@ def run(plotIt=True):
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ax.grid(color='k', alpha=0.5, linestyle='dashed', linewidth=0.5)
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rxOffset=10.
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bzi = EM.FDEM.Rx(np.array([[rxOffset, 0., 1e-3]]), 'bzi')
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rxOffset=10.
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bzi = EM.FDEM.Rx.bField(np.array([[rxOffset, 0., 1e-3]]), orientation='z', real_or_imag='imag')
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freqs = np.logspace(1,3,10)
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srcLoc = np.array([0., 0., 10.])
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srcList = []
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[srcList.append(EM.FDEM.Src.MagDipole([bzi],freq, srcLoc,orientation='Z')) for freq in freqs]
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srcList = [EM.FDEM.Src.MagDipole([bzi],freq, srcLoc,orientation='Z') for freq in freqs]
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survey = EM.FDEM.Survey(srcList)
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prb = EM.FDEM.Problem_b(mesh, mapping=mapping)
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prb = EM.FDEM.Problem3D_b(mesh, mapping=mapping)
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try:
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from pymatsolver import MumpsSolver
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@@ -0,0 +1,275 @@
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from SimPEG import *
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from SimPEG.EM import FDEM, Analytics, mu_0
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import time
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try:
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from pymatsolver import MumpsSolver
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solver = MumpsSolver
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except Exception:
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solver = SolverLU
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pass
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def run(plotIt=True):
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"""
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EM: Schenkel and Morrison Casing Model
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======================================
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Here we create and run a FDEM forward simulation to calculate the vertical
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current inside a steel-cased. The model is based on the Schenkel and
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Morrison Casing Model, and the results are used in a 2016 SEG abstract by
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Yang et al.
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- Schenkel, C.J., and H.F. Morrison, 1990, Effects of well casing on potential field measurements using downhole current sources: Geophysical prospecting, 38, 663-686.
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The model consists of:
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- Air: Conductivity 1e-8 S/m, above z = 0
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- Background: conductivity 1e-2 S/m, below z = 0
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- Casing: conductivity 1e6 S/m
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- 300m long
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- radius of 0.1m
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- thickness of 6e-3m
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Inside the casing, we take the same conductivity as the background.
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We are using an EM code to simulate DC, so we use frequency low enough
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that the skin depth inside the casing is longer than the casing length (f
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= 1e-6 Hz). The plot produced is of the current inside the casing.
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These results are shown in the SEG abstract by Yang et al., 2016: 3D DC
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resistivity modeling of steel casing for reservoir monitoring using
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equivalent resistor network. The solver used to produce these results and
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achieve the CPU time of ~30s is Mumps, which was installed using pymatsolver_
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.. _pymatsolver: https://github.com/rowanc1/pymatsolver
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This example is on figshare: https://dx.doi.org/10.6084/m9.figshare.3126961.v1
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If you would use this example for a code comparison, or build upon it, a
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citation would be much appreciated!
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"""
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if plotIt:
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import matplotlib.pylab as plt
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# ------------------ MODEL ------------------
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sigmaair = 1e-8 # air
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sigmaback = 1e-2 # background
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sigmacasing = 1e6 # casing
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sigmainside = sigmaback # inside the casing
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casing_t = 0.006 # 1cm thickness
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casing_l = 300 # length of the casing
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casing_r = 0.1
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casing_a = casing_r - casing_t/2. # inner radius
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casing_b = casing_r + casing_t/2. # outer radius
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casing_z = np.r_[-casing_l,0.]
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# ------------------ SURVEY PARAMETERS ------------------
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freqs = np.r_[1e-6] #[1e-1, 1, 5] # frequencies
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dsz = -300 # down-hole z source location
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src_loc = np.r_[0.,0.,dsz]
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inf_loc = np.r_[0.,0.,1e4]
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print 'Skin Depth: ', [(500./np.sqrt(sigmaback*_)) for _ in freqs]
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# ------------------ MESH ------------------
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# fine cells near well bore
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csx1, csx2 = 2e-3, 60.
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pfx1, pfx2 = 1.3, 1.3
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ncx1 = np.ceil(casing_b/csx1+2)
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# pad nicely to second cell size
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npadx1 = np.floor(np.log(csx2/csx1) / np.log(pfx1))
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hx1a,hx1b = Utils.meshTensor([(csx1,ncx1)]),Utils.meshTensor([(csx1,npadx1,pfx1)])
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dx1 = sum(hx1a)+sum(hx1b)
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dx1 = np.floor(dx1/csx2)
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hx1b *= (dx1*csx2 - sum(hx1a))/sum(hx1b)
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# second chunk of mesh
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dx2 = 300. # uniform mesh out to here
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ncx2 = np.ceil((dx2 - dx1)/csx2)
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npadx2 = 45
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hx2a, hx2b = Utils.meshTensor([(csx2,ncx2)]), Utils.meshTensor([(csx2,npadx2,pfx2)])
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hx = np.hstack([hx1a,hx1b,hx2a,hx2b])
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# z-direction
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csz = 0.05
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nza = 10
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ncz, npadzu, npadzd = np.int(np.ceil(np.diff(casing_z)[0]/csz))+10, 68, 68 # cell size, number of core cells, number of padding cells in the x- direction
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hz = Utils.meshTensor([(csz,npadzd,-1.3), (csz,ncz), (csz,npadzu,1.3)]) # vector of cell widths in the z-direction
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# Mesh
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mesh = Mesh.CylMesh([hx,1.,hz], [0.,0.,-np.sum(hz[:npadzu+ncz-nza])])
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print 'Mesh Extent xmax: %f,: zmin: %f, zmax: %f'%(mesh.vectorCCx.max(), mesh.vectorCCz.min(), mesh.vectorCCz.max())
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print 'Number of cells', mesh.nC
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if plotIt is True:
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fig, ax = plt.subplots(1, 1, figsize=(6, 4))
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ax.set_title('Simulation Mesh')
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mesh.plotGrid(ax=ax)
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plt.show()
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# Put the model on the mesh
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sigWholespace = sigmaback*np.ones((mesh.nC))
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sigBack = sigWholespace.copy()
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sigBack[mesh.gridCC[:,2] > 0.] = sigmaair
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sigCasing = sigBack.copy()
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iCasingZ = (mesh.gridCC[:,2] <= casing_z[1]) & (mesh.gridCC[:,2] >= casing_z[0])
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iCasingX = (mesh.gridCC[:,0] >= casing_a) & (mesh.gridCC[:,0] <= casing_b)
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iCasing = iCasingX & iCasingZ
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sigCasing[iCasing] = sigmacasing
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if plotIt is True:
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# plotting parameters
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xlim = np.r_[0., 0.2]
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zlim = np.r_[-350., 10.]
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clim_sig = np.r_[-8,6]
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# plot models
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fig, ax = plt.subplots(1,1,figsize=(4,4))
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f = plt.colorbar(mesh.plotImage(np.log10(sigCasing),ax=ax)[0], ax=ax)
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ax.grid(which='both')
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ax.set_title('Log_10 (Sigma)')
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ax.set_xlim(xlim)
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ax.set_ylim(zlim)
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f.set_clim(clim_sig)
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plt.show()
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# -------------- Sources --------------------
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# Define Custom Current Sources
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# surface source
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sg_x = np.zeros(mesh.vnF[0],dtype=complex)
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sg_y = np.zeros(mesh.vnF[1],dtype=complex)
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sg_z = np.zeros(mesh.vnF[2],dtype=complex)
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nza = 2 # put the wire two cells above the surface
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ncin = 2
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# vertically directed wire
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sgv_indx = (mesh.gridFz[:,0] > casing_a) & (mesh.gridFz[:,0] < casing_a + csx1) # hook it up to casing at the surface
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sgv_indz = (mesh.gridFz[:,2] <= +csz*nza) & (mesh.gridFz[:,2] >= -csz*2)
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sgv_ind = sgv_indx & sgv_indz
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sg_z[sgv_ind] = -1.
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# horizontally directed wire
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sgh_indx = (mesh.gridFx[:,0] > casing_a) & (mesh.gridFx[:,0] <= inf_loc[2])
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sgh_indz = (mesh.gridFx[:,2] > csz*(nza-0.5)) & (mesh.gridFx[:,2] < csz*(nza+0.5))
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sgh_ind = sgh_indx & sgh_indz
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sg_x[sgh_ind] = -1.
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sgv2_indx = (mesh.gridFz[:,0] >= mesh.gridFx[sgh_ind,0].max()) & (mesh.gridFz[:,0] <= inf_loc[2]*1.2) # hook it up to casing at the surface
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sgv2_indz = (mesh.gridFz[:,2] <= +csz*nza) & (mesh.gridFz[:,2] >= -csz*2)
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sgv2_ind = sgv2_indx & sgv2_indz
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sg_z[sgv2_ind] = 1.
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# assemble the source
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sg = np.hstack([sg_x,sg_y,sg_z])
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sg_p = [FDEM.Src.RawVec_e([],_,sg/mesh.area) for _ in freqs]
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# downhole source
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dg_x = np.zeros(mesh.vnF[0],dtype=complex)
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dg_y = np.zeros(mesh.vnF[1],dtype=complex)
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dg_z = np.zeros(mesh.vnF[2],dtype=complex)
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# vertically directed wire
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dgv_indx = (mesh.gridFz[:,0] < csx1) # go through the center of the well
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dgv_indz = (mesh.gridFz[:,2] <= +csz*nza) & (mesh.gridFz[:,2] > dsz + csz/2.)
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dgv_ind = dgv_indx & dgv_indz
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dg_z[dgv_ind] = -1.
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# couple to the casing downhole
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dgh_indx = mesh.gridFx[:,0] < casing_a + csx1
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dgh_indz = (mesh.gridFx[:,2] < dsz + csz) & (mesh.gridFx[:,2] >= dsz)
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dgh_ind = dgh_indx & dgh_indz
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dg_x[dgh_ind] = 1.
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# horizontal part at surface
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dgh2_indx = mesh.gridFx[:,0] <= inf_loc[2]*1.2
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dgh2_indz = sgh_indz.copy()
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dgh2_ind = dgh2_indx & dgh2_indz
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dg_x[dgh2_ind] = -1.
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# vertical part at surface
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dgv2_ind = sgv2_ind.copy()
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dg_z[dgv2_ind] = 1.
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||||
|
||||
# assemble the source
|
||||
dg = np.hstack([dg_x,dg_y,dg_z])
|
||||
dg_p = [FDEM.Src.RawVec_e([],_,dg/mesh.area) for _ in freqs]
|
||||
|
||||
# ------------ Problem and Survey ---------------
|
||||
survey = FDEM.Survey(sg_p + dg_p)
|
||||
mapping = [('sigma', Maps.IdentityMap(mesh))]
|
||||
problem = FDEM.Problem3D_h(mesh, mapping=mapping)
|
||||
problem.pair(survey)
|
||||
|
||||
# ------------- Solve ---------------------------
|
||||
t0 = time.time()
|
||||
fieldsCasing = problem.fields(sigCasing)
|
||||
print 'Time to solve 2 sources', time.time() - t0
|
||||
|
||||
# Plot current
|
||||
|
||||
# current density
|
||||
jn0 = fieldsCasing[dg_p,'j']
|
||||
jn1 = fieldsCasing[sg_p,'j']
|
||||
|
||||
# current
|
||||
in0 = [mesh.area*fieldsCasing[dg_p,'j'][:,i] for i in range(len(freqs))]
|
||||
in1 = [mesh.area*fieldsCasing[sg_p,'j'][:,i] for i in range(len(freqs))]
|
||||
|
||||
in0 = np.vstack(in0).T
|
||||
in1 = np.vstack(in1).T
|
||||
|
||||
# integrate to get z-current inside casing
|
||||
inds_inx = (mesh.gridFz[:,0] >= casing_a) & (mesh.gridFz[:,0] <= casing_b)
|
||||
inds_inz = (mesh.gridFz[:,2] >= dsz ) & (mesh.gridFz[:,2] <= 0)
|
||||
inds_fz = inds_inx & inds_inz
|
||||
|
||||
indsx = [False]*mesh.nFx
|
||||
inds = list(indsx) + list(inds_fz)
|
||||
|
||||
in0_in = in0[np.r_[inds]]
|
||||
in1_in = in1[np.r_[inds]]
|
||||
z_in = mesh.gridFz[inds_fz,2]
|
||||
|
||||
in0_in = in0_in.reshape([in0_in.shape[0]/3,3])
|
||||
in1_in = in1_in.reshape([in1_in.shape[0]/3,3])
|
||||
z_in = z_in.reshape([z_in.shape[0]/3,3])
|
||||
|
||||
I0 = in0_in.sum(1).real
|
||||
I1 = in1_in.sum(1).real
|
||||
z_in = z_in[:,0]
|
||||
|
||||
if plotIt is True:
|
||||
fig, ax = plt.subplots(1,2,figsize=(12,4))
|
||||
|
||||
ax[0].plot(z_in,np.absolute(I0), z_in,np.absolute(I1))
|
||||
ax[0].legend(['top casing', 'bottom casing'],loc='best')
|
||||
ax[0].set_title('Magnitude of Vertical Current in Casing')
|
||||
|
||||
ax[1].semilogy(z_in,np.absolute(I0), z_in,np.absolute(I1))
|
||||
ax[1].legend(['top casing', 'bottom casing'],loc='best')
|
||||
ax[1].set_title('Magnitude of Vertical Current in Casing')
|
||||
ax[1].set_ylim([1e-2, 1.])
|
||||
|
||||
plt.show()
|
||||
|
||||
if __name__ == '__main__':
|
||||
run()
|
||||
|
||||
@@ -0,0 +1,132 @@
|
||||
from SimPEG import *
|
||||
|
||||
|
||||
def run(N=200, plotIt=True):
|
||||
"""
|
||||
Inversion: Linear Problem
|
||||
=========================
|
||||
|
||||
Here we go over the basics of creating a linear problem and inversion.
|
||||
|
||||
"""
|
||||
|
||||
|
||||
np.random.seed(1)
|
||||
|
||||
std_noise = 1e-2
|
||||
|
||||
mesh = Mesh.TensorMesh([N])
|
||||
|
||||
m0 = np.ones(mesh.nC) * 1e-4
|
||||
nk = 10
|
||||
jk = np.linspace(1.,nk,nk)
|
||||
p = -2.
|
||||
q = 1.
|
||||
|
||||
g = lambda k: 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)
|
||||
survey = Survey.LinearSurvey()
|
||||
survey.pair(prob)
|
||||
survey.dobs = prob.fields(mtrue) + std_noise * np.random.randn(nk)
|
||||
#survey.makeSyntheticData(mtrue, std=std_noise)
|
||||
|
||||
wd = np.ones(nk) * std_noise
|
||||
|
||||
#print survey.std[0]
|
||||
#M = prob.mesh
|
||||
# Distance weighting
|
||||
wr = np.sum(prob.G**2.,axis=0)**0.5
|
||||
wr = ( wr/np.max(wr) )
|
||||
|
||||
reg = Regularization.Simple(mesh)
|
||||
reg.wght = wr
|
||||
|
||||
dmis = DataMisfit.l2_DataMisfit(survey)
|
||||
dmis.Wd = 1./wd
|
||||
|
||||
opt = Optimization.ProjectedGNCG(maxIter=30,lower=-2.,upper=2., maxIterCG= 20, tolCG = 1e-4)
|
||||
invProb = InvProblem.BaseInvProblem(dmis, reg, opt)
|
||||
invProb.curModel = m0
|
||||
|
||||
beta = Directives.BetaSchedule(coolingFactor=2, coolingRate=1)
|
||||
target = Directives.TargetMisfit()
|
||||
|
||||
betaest = Directives.BetaEstimate_ByEig()
|
||||
inv = Inversion.BaseInversion(invProb, directiveList=[beta, betaest, target])
|
||||
|
||||
|
||||
mrec = inv.run(m0)
|
||||
ml2 = mrec
|
||||
print "Final misfit:" + str(invProb.dmisfit.eval(mrec))
|
||||
|
||||
# Switch regularization to sparse
|
||||
phim = invProb.phi_m_last
|
||||
phid = invProb.phi_d
|
||||
|
||||
reg = Regularization.Sparse(mesh)
|
||||
|
||||
#==============================================================================
|
||||
# fig, axes = plt.subplots(1,2,figsize=(12*1.2,4*1.2))
|
||||
# dmdx = reg.mesh.cellDiffxStencil * mrec
|
||||
# plt.plot(np.sort(dmdx))
|
||||
#==============================================================================
|
||||
|
||||
#reg.recModel = mrec
|
||||
reg.wght = np.ones(mesh.nC)
|
||||
reg.mref = np.zeros(mesh.nC)
|
||||
reg.eps_p = 5e-2
|
||||
reg.eps_q = 1e-2
|
||||
reg.norms = [0., 0., 2., 2.]
|
||||
reg.wght = wr
|
||||
|
||||
opt = Optimization.ProjectedGNCG(maxIter=10 ,lower=-2.,upper=2., maxIterLS = 20, maxIterCG= 20, tolCG = 1e-3)
|
||||
invProb = InvProblem.BaseInvProblem(dmis, reg, opt, beta = invProb.beta*2.)
|
||||
beta = Directives.BetaSchedule(coolingFactor=1, coolingRate=1)
|
||||
#betaest = Directives.BetaEstimate_ByEig()
|
||||
target = Directives.TargetMisfit()
|
||||
IRLS =Directives.Update_IRLS( phi_m_last = phim, phi_d_last = phid )
|
||||
|
||||
inv = Inversion.BaseInversion(invProb, directiveList=[beta,IRLS])
|
||||
|
||||
m0 = mrec
|
||||
|
||||
# Run inversion
|
||||
mrec = inv.run(m0)
|
||||
|
||||
print "Final misfit:" + str(invProb.dmisfit.eval(mrec))
|
||||
|
||||
|
||||
if plotIt:
|
||||
import matplotlib.pyplot as plt
|
||||
|
||||
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(mesh.vectorCCx, mtrue, 'b-')
|
||||
axes[1].plot(mesh.vectorCCx, ml2, 'r-')
|
||||
#axes[1].legend(('True Model', 'Recovered Model'))
|
||||
axes[1].set_ylim(-1.0,1.25)
|
||||
|
||||
axes[1].plot(mesh.vectorCCx, mrec, 'k-',lw = 2)
|
||||
axes[1].legend(('True Model', 'Smooth l2-l2',
|
||||
'Sparse lp:' + str(reg.norms[0]) + ', lqx:' + str(reg.norms[1]) ), fontsize = 12)
|
||||
plt.show()
|
||||
|
||||
return prob, survey, mesh, mrec
|
||||
|
||||
if __name__ == '__main__':
|
||||
run()
|
||||
@@ -100,7 +100,7 @@ def run(plotIt=True):
|
||||
# Regularization - with a regularization mesh
|
||||
regMesh = simpeg.Mesh.TensorMesh([m1d.hx[problem.mapping.sigmaMap.maps[-1].indActive]],m1d.x0)
|
||||
reg = simpeg.Regularization.Tikhonov(regMesh)
|
||||
reg.smoothModel = True
|
||||
reg.mrefInSmooth = True
|
||||
reg.alpha_s = 1e-7
|
||||
reg.alpha_x = 1.
|
||||
# Inversion problem
|
||||
|
||||
@@ -5,9 +5,11 @@ import DC_Analytic_Dipole
|
||||
import DC_Forward_PseudoSection
|
||||
import EM_FDEM_1D_Inversion
|
||||
import EM_FDEM_Analytic_MagDipoleWholespace
|
||||
import EM_Schenkel_Morrison_Casing
|
||||
import EM_TDEM_1D_Inversion
|
||||
import FLOW_Richards_1D_Celia1990
|
||||
import Forward_BasicDirectCurrent
|
||||
import Inversion_IRLS
|
||||
import Inversion_Linear
|
||||
import Mesh_Basic_PlotImage
|
||||
import Mesh_Basic_Types
|
||||
@@ -19,7 +21,7 @@ import Mesh_Tensor_Creation
|
||||
import MT_1D_ForwardAndInversion
|
||||
import MT_3D_Foward
|
||||
|
||||
__examples__ = ["DC_Analytic_Dipole", "DC_Forward_PseudoSection", "EM_FDEM_1D_Inversion", "EM_FDEM_Analytic_MagDipoleWholespace", "EM_TDEM_1D_Inversion", "FLOW_Richards_1D_Celia1990", "Forward_BasicDirectCurrent", "Inversion_Linear", "Mesh_Basic_PlotImage", "Mesh_Basic_Types", "Mesh_Operators_CahnHilliard", "Mesh_QuadTree_Creation", "Mesh_QuadTree_FaceDiv", "Mesh_QuadTree_HangingNodes", "Mesh_Tensor_Creation", "MT_1D_ForwardAndInversion", "MT_3D_Foward"]
|
||||
__examples__ = ["DC_Analytic_Dipole", "DC_Forward_PseudoSection", "EM_FDEM_1D_Inversion", "EM_FDEM_Analytic_MagDipoleWholespace", "EM_Schenkel_Morrison_Casing", "EM_TDEM_1D_Inversion", "FLOW_Richards_1D_Celia1990", "Forward_BasicDirectCurrent", "Inversion_IRLS", "Inversion_Linear", "Mesh_Basic_PlotImage", "Mesh_Basic_Types", "Mesh_Operators_CahnHilliard", "Mesh_QuadTree_Creation", "Mesh_QuadTree_FaceDiv", "Mesh_QuadTree_HangingNodes", "Mesh_Tensor_Creation", "MT_1D_ForwardAndInversion", "MT_3D_Foward"]
|
||||
|
||||
##### AUTOIMPORTS #####
|
||||
|
||||
|
||||
Reference in New Issue
Block a user