allow complex mu for forward time-domain em1d (simpeg#1739)

jcapriot · web-flow · commit 8c62b2faac72 · 2025-12-09T09:00:12.000-07:00
#### Summary Support complex permeability in forward 1D time-domain em simulations. #### PR Checklist * [x] If this is a work in progress PR, set as a Draft PR * [x] Linted my code according to the [style guides](https://docs.simpeg.xyz/latest/content/getting_started/contributing/code-style.html). * [x] Added [tests](https://docs.simpeg.xyz/latest/content/getting_started/contributing/testing.html) to verify changes to the code. * [x] Added necessary documentation to any new functions/classes following the expect [style](https://docs.simpeg.xyz/latest/content/getting_started/contributing/documentation.html). * [x] Marked as ready for review (if this is was a draft PR), and converted to a Pull Request * [x] Tagged ``@simpeg/simpeg-developers`` when ready for review. #### What does this implement/fix? removes cast to `real` #### Additional information `geoana` supports complex permeability in the kernel, so the cast to real is unnecessary.
diff --git a/.ci/environment_test.yml b/.ci/environment_test.yml
@@ -7,7 +7,7 @@ dependencies:
   - pymatsolver>=0.3
   - matplotlib-base
   - discretize>=0.12
-  - geoana>=0.7
+  - geoana>=0.8.1
   - libdlf
   - typing_extensions
 
diff --git a/environment.yml b/environment.yml
@@ -9,7 +9,7 @@ dependencies:
   - pymatsolver>=0.3
   - matplotlib-base
   - discretize>=0.12
-  - geoana>=0.7
+  - geoana>=0.8.1
   - libdlf
   - typing_extensions
 
diff --git a/pyproject.toml b/pyproject.toml
@@ -20,7 +20,7 @@ dependencies = [
     "pymatsolver>=0.3",
     "matplotlib",
     "discretize>=0.12",
-    "geoana>=0.7",
+    "geoana>=0.8.1",
     "libdlf",
     "typing_extensions; python_version<'3.13'",
 ]
diff --git a/simpeg/electromagnetics/time_domain/simulation_1d.py b/simpeg/electromagnetics/time_domain/simulation_1d.py
@@ -243,8 +243,7 @@ def fields(self, m):
         sig = self.compute_complex_sigma(frequencies)
         mu = self.compute_complex_mu(frequencies)
 
-        # TODO geoana currently only support real mu input.
-        rTE = rTE_forward(frequencies, unique_lambs, sig, mu.real, self.thicknesses)
+        rTE = rTE_forward(frequencies, unique_lambs, sig, mu, self.thicknesses)
         rTE = rTE[:, inv_lambs]
         v = ((C0s * rTE) @ self._fhtfilt.j0 + (C1s * rTE) @ self._fhtfilt.j1) @ W.T
 
diff --git a/tests/em/em1d/test_EM1D_FD_fwd.py b/tests/em/em1d/test_EM1D_FD_fwd.py
@@ -606,5 +606,42 @@ def test_rx_loc_shapes(rx_class, n_locs1, n_locs2, orientation, component):
     np.testing.assert_allclose(J, J[0], rtol=1e-12)
 
 
+@pytest.mark.parametrize("prop", ["conductivity", "permeability"])
+def test_real_vs_complex(prop):
+    """just makes sure that it respect a complex conductivity, in that it is different
+    from the real value.
+    """
+    offsets = np.linspace(5, 20, 10)
+    rx1_locs = np.pad(offsets[:, None], ((0, 0), (0, 2)), constant_values=0)
+    rx_list = [
+        fdem.receivers.PointMagneticField(rx1_locs, orientation="x", component="real"),
+        fdem.receivers.PointMagneticField(rx1_locs, orientation="x", component="imag"),
+    ]
+
+    src = fdem.sources.MagDipole(rx_list, frequency=0.1)
+    srv = fdem.Survey(src)
+
+    sim = fdem.Simulation1DLayered(survey=srv, sigma=[1.0])
+    if prop == "conductivity":
+        sim.eta = 0.5
+    else:
+        sim.dchi = 1.0
+
+    d_c = sim.dpred(None)
+
+    # create another simulation that is just the real part of sigma and mu
+    sim_real = fdem.Simulation1DLayered(survey=srv, sigma=[1.0])
+
+    # hijack these to just return the real values from the complex valued simulation
+    # that way we are sure the two simulations have the same real parts of mu and sigma
+    # but different imaginary portions
+    sim_real.compute_complex_sigma = lambda f: sim.compute_complex_sigma(f).real
+    sim_real.compute_complex_mu = lambda f: sim.compute_complex_mu(f).real
+
+    d_r = sim_real.dpred(None)
+
+    assert np.all(d_r != d_c)
+
+
 if __name__ == "__main__":
     unittest.main()
diff --git a/tests/em/em1d/test_EM1D_TD_general_fwd.py b/tests/em/em1d/test_EM1D_TD_general_fwd.py
@@ -1,4 +1,5 @@
 import unittest
+import pytest
 from simpeg import maps
 import simpeg.electromagnetics.time_domain as tdem
 from simpeg.electromagnetics.utils import convolve_with_waveform
@@ -285,5 +286,68 @@ def test_backwards_compatible_filter_key():
     assert sim.time_filter == "key_81_2009"
 
 
+@pytest.mark.parametrize("prop", ["conductivity", "permeability"])
+def test_real_vs_complex(prop):
+    """just makes sure that it respect a complex conductivity, in that it is different
+    from the real value.
+    """
+    source_location = np.array([0.0, 0.0, 100.0 + 1e-5])
+    receiver_locations = np.array([[0.0, 0.0, 100.0 + 1e-5]])
+    receiver_orientation = "z"  # "x", "y" or "z"
+    times = np.logspace(-5, -2, 31)
+    radius = 20.0
+
+    # Waveform
+    waveform = tdem.sources.TriangularWaveform(
+        start_time=-0.01, peak_time=-0.005, off_time=0.0
+    )
+
+    # Receiver list
+
+    # Define receivers at each location.
+    b_receiver = tdem.receivers.PointMagneticFluxDensity(
+        receiver_locations, times, receiver_orientation
+    )
+    dbzdt_receiver = tdem.receivers.PointMagneticFluxTimeDerivative(
+        receiver_locations, times, receiver_orientation
+    )
+    receivers_list = [
+        b_receiver,
+        dbzdt_receiver,
+    ]  # Make a list containing all receivers even if just one
+
+    # Must define the transmitter properties and associated receivers
+    source_list = [
+        tdem.sources.CircularLoop(
+            receivers_list,
+            location=source_location,
+            waveform=waveform,
+            radius=radius,
+        )
+    ]
+
+    survey = tdem.Survey(source_list)
+
+    sim = tdem.Simulation1DLayered(survey=survey, sigma=[1.0])
+    if prop == "conductivity":
+        sim.eta = 0.5
+    else:
+        sim.dchi = 1.0
+
+    d_c = sim.dpred(None)
+
+    sim_real = tdem.Simulation1DLayered(survey=survey, sigma=[1.0])
+
+    # hijack these to just return the real values from the complex valued simulation
+    # that way we are sure the two simulations have the same real parts of mu and sigma
+    # but different imaginary portions
+    sim_real.compute_complex_sigma = lambda f: sim.compute_complex_sigma(f).real
+    sim_real.compute_complex_mu = lambda f: sim.compute_complex_mu(f).real
+
+    d_r = sim_real.dpred(None)
+
+    assert np.all(d_r != d_c)
+
+
 if __name__ == "__main__":
     unittest.main()

Original file line number	Diff line number	Diff line change
`@@ -20,7 +20,7 @@ dependencies = [`
`20`	`20`	`"pymatsolver>=0.3",`
`21`	`21`	`"matplotlib",`
`22`	`22`	`"discretize>=0.12",`
`23`		`- "geoana>=0.7",`
	`23`	`+ "geoana>=0.8.1",`
`24`	`24`	`"libdlf",`
`25`	`25`	`"typing_extensions; python_version<'3.13'",`
`26`	`26`	`]`