def appResPhsHalfspace_eFrom_ps_Norm(sigmaHalf, appR=True, expMap=False):
if appR:
label = "resistivity"
else:
label = "phase"
print(
"Apparent {:s} test of eFormulation primary/secondary at {:g}\n\n".format(
label, sigmaHalf
)
)
# Calculate the app phs
survey, simulation = nsem.utils.test_utils.setupSimpegNSEM_ePrimSec(
nsem.utils.test_utils.halfSpace(sigmaHalf), expMap=expMap
)
data = nsem.Data(survey=survey, dobs=simulation.dpred(simulation.model))
recData = data.toRecArray("Complex")
app_rpxy = nsem.utils.appResPhs(recData["freq"], recData["zxy"])[0]
# app_rpyx = nsem.utils.appResPhs(recData['freq'], recData['zyx'])[0]
if appR:
return np.linalg.norm(
np.abs(np.log10(app_rpxy[0]) - np.log10(1.0 / sigmaHalf))
* np.log10(sigmaHalf)
)
else:
return np.linalg.norm(np.abs(app_rpxy[1] + 135.0) / 135.0)
def calculateAnalyticSolution(source_list, mesh, model):
surveyAna = nsem.Survey(source_list)
data1D = nsem.Data(surveyAna)
for src in surveyAna.source_list:
elev = src.receiver_list[0].locations[0]
anaEd, anaEu, anaHd, anaHu = nsem.utils.analytic_1d.getEHfields(
mesh, model, src.frequency, elev)
anaE = anaEd + anaEu
anaH = anaHd + anaHu
# Scale the solution
# anaE = (anaEtemp/anaEtemp[-1])#.conj()
# anaH = (anaHtemp/anaEtemp[-1])#.conj()
anaZ = anaE / anaH
for rx in src.receiver_list:
data1D[src, rx] = getattr(anaZ, rx.component)
return data1D
def run(plotIt=True):
"""
MT: 3D: Forward
===============
Forward model 3D MT data.
"""
# Make a mesh
M = discretize.TensorMesh(
[
[(100, 9, -1.5), (100.0, 13), (100, 9, 1.5)],
[(100, 9, -1.5), (100.0, 13), (100, 9, 1.5)],
[(50, 10, -1.6), (50.0, 10), (50, 6, 2)],
],
x0=["C", "C", -14926.8217],
)
# Setup the model
conds = [1, 1e-2]
sig = utils.model_builder.defineBlock(M.gridCC, [-100, -100, -350],
[100, 100, -150], conds)
sig[M.gridCC[:, 2] > 0] = 1e-8
sig[M.gridCC[:, 2] < -1000] = 1e-1
sigBG = np.zeros(M.nC) + conds[1]
sigBG[M.gridCC[:, 2] > 0] = 1e-8
if plotIt:
collect_obj = M.plotSlice(np.log10(sig), grid=True, normal="X")[0]
color_bar = plt.colorbar(collect_obj)
# Setup the the survey object
# Receiver locations
rx_x, rx_y = np.meshgrid(np.arange(-600, 601, 100),
np.arange(-600, 601, 100))
rx_loc = np.hstack((utils.mkvc(rx_x, 2), utils.mkvc(rx_y, 2),
np.zeros((np.prod(rx_x.shape), 1))))
# Make a receiver list
receiver_list = []
for rx_orientation in ["xx", "xy", "yx", "yy"]:
receiver_list.append(
NSEM.Rx.Point3DImpedance(rx_loc, rx_orientation, "real"))
receiver_list.append(
NSEM.Rx.Point3DImpedance(rx_loc, rx_orientation, "imag"))
for rx_orientation in ["zx", "zy"]:
receiver_list.append(
NSEM.Rx.Point3DTipper(rx_loc, rx_orientation, "real"))
receiver_list.append(
NSEM.Rx.Point3DTipper(rx_loc, rx_orientation, "imag"))
# Source list
source_list = [
NSEM.Src.Planewave_xy_1Dprimary(receiver_list, freq)
for freq in np.logspace(4, -2, 13)
]
# Survey MT
survey = NSEM.Survey(source_list)
# Setup the problem object
problem = NSEM.Simulation3DPrimarySecondary(M,
survey=survey,
solver=Solver,
sigma=sig,
sigmaPrimary=sigBG)
# Calculate the data
# data = problem.make_synthetic_data(relative_error=0.1, add_noise=True)
data = NSEM.Data(survey=survey, dobs=problem.dpred())
# Add standard deviation to the data - 10% relative error and 0 floor
data.relative_error = 0.1
data.noise_floor = 0.0
# Add plots
if plotIt:
# Plot the data
# On and off diagonal (on left and right axis, respectively)
fig, axes = plt.subplots(2, 1, figsize=(7, 5))
plt.subplots_adjust(right=0.8)
[(ax.invert_xaxis(), ax.set_xscale("log")) for ax in axes]
ax_r, ax_p = axes
ax_r.set_yscale("log")
ax_r.set_ylabel("Apparent resistivity [xy-yx]")
ax_r_on = ax_r.twinx()
ax_r_on.set_yscale("log")
ax_r_on.set_ylabel("Apparent resistivity [xx-yy]")
ax_p.set_ylabel("Apparent phase")
ax_p.set_xlabel("Frequency [Hz]")
# Start plotting
ax_r = data.plot_app_res(np.array([-200, 0]),
components=["xy", "yx"],
ax=ax_r,
errorbars=True)
ax_r_on = data.plot_app_res(np.array([-200, 0]),
components=["xx", "yy"],
ax=ax_r_on,
errorbars=True)
ax_p = data.plot_app_phs(
np.array([-200, 0]),
components=["xx", "xy", "yx", "yy"],
ax=ax_p,
errorbars=True,
)
ax_p.legend(bbox_to_anchor=(1.05, 1), loc=2)