Fitter improvement

Change DispersionFitter to a pydantic.BaseModel object.
Make eps_data, lossy, freqs, frequency_range into @Property types
More error handling in StableDispersiveFitter
Allow to load dispersive data directly by providing URL to txt or csv file
Allow to filter wavelength range for fitting
Add tunable eps_inf as a variable for optimization

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 - ``Selmeier.from_dispersion()`` method to quickly make a single-pole fit for lossless weakly dispersive materials.
+- Stable dispersive material fits via webservice.
+- Allow to load dispersive data directly by providing URL to txt or csv file
 - Validates simulation based on discretized size.
 
 ### Changed

tests/_test_fit_web.py

@@ -1,16 +1,14 @@
 import numpy as np
-import sys
 
-sys.path.append("../tidy3d_client_revamp")
-from tidy3d.plugins import StableDispersionFitter
+from tidy3d.plugins import StableDispersionFitter, AdvancedFitterParam
 
 
 def test_dispersion_load_list():
     """performs a fit on some random data"""
     num_data = 10
     n_data = np.random.random(num_data)
     wvls = np.linspace(1, 2, num_data)
-    fitter = StableDispersionFitter(wvls, n_data)
+    fitter = StableDispersionFitter(wvl_um=wvls, n_data=n_data)
 
     num_poles = 3
     num_tries = 10
@@ -27,7 +25,7 @@ def test_dispersion_load_file():
     fitter = StableDispersionFitter.from_file("tests/data/nk_data.csv", skiprows=1, delimiter=",")
 
     num_poles = 3
-    num_tries = 30
+    num_tries = 10
     tolerance_rms = 1e-3
     best_medium, best_rms = fitter.fit(
         num_tries=num_tries, num_poles=num_poles, tolerance_rms=tolerance_rms
@@ -36,5 +34,30 @@ def test_dispersion_load_file():
     print(best_medium.eps_model(1e12))
 
 
-if __name__ == "__main__":
-    test_dispersion_load_file()
+def test_dispersion_load_url():
+
+    url_csv = "https://refractiveindex.info/data_csv.php?datafile=data/main/Ag/Johnson.yml"
+    fitter = StableDispersionFitter.from_url(url_csv)
+
+    num_poles = 2
+    num_tries = 10
+    tolerance_rms = 1e-3
+    best_medium, best_rms = fitter.fit(
+        num_tries=num_tries,
+        num_poles=num_poles,
+        tolerance_rms=tolerance_rms,
+        advanced_param=AdvancedFitterParam(constraint="hard", bound_eps_inf=10),
+    )
+    print(best_rms)
+    print(best_medium.eps_inf)
+
+    fitter.wvl_range = [1.0, 1.3]
+    print(len(fitter.freqs))
+    best_medium, best_rms = fitter.fit(
+        num_tries=num_tries,
+        num_poles=num_poles,
+        tolerance_rms=tolerance_rms,
+        advanced_param=AdvancedFitterParam(constraint="hard", bound_eps_inf=10),
+    )
+    print(best_rms)
+    print(best_medium.eps_inf)

tests/test_plugins.py

@@ -5,8 +5,6 @@
 import tidy3d as td
 
 from tidy3d.plugins import DispersionFitter
-from tidy3d.plugins.dispersion.fit import _poles_to_coeffs, _coeffs_to_poles
-from tidy3d.plugins.dispersion.fit import _pack_coeffs, _unpack_coeffs
 
 from tidy3d.plugins import ModeSolver
 from tidy3d.plugins import Near2Far
@@ -84,11 +82,14 @@ def test_dispersion():
     num_data = 10
     n_data = np.random.random(num_data)
     wvls = np.linspace(1, 2, num_data)
-    fitter = DispersionFitter(wvls, n_data)
-    medium, rms = fitter.fit_single()
+    fitter = DispersionFitter(wvl_um=wvls, n_data=n_data)
+    medium, rms = fitter._fit_single()
     medium, rms = fitter.fit(num_tries=2)
     medium.to_file("tests/tmp/medium_fit.json")
 
+    k_data = np.random.random(num_data)
+    fitter = DispersionFitter(wvl_um=wvls, n_data=n_data, k_data=k_data)
+
 
 def test_dispersion_load():
     """loads dispersion model from nk data file"""
@@ -101,3 +102,17 @@ def test_dispersion_plot():
     fitter = DispersionFitter.from_file("tests/data/nk_data.csv", skiprows=1, delimiter=",")
     medium, rms = fitter.fit(num_tries=20)
     fitter.plot(medium)
+
+
+def test_dispersion_set_wvg_range():
+    """set wavelength range function"""
+    num_data = 50
+    n_data = np.random.random(num_data)
+    wvls = np.linspace(1, 2, num_data)
+    fitter = DispersionFitter(wvl_um=wvls, n_data=n_data)
+
+    wvl_min = np.random.random(1)[0] * 0.5 + 1
+    wvl_max = wvl_min + 0.5
+    fitter.wvl_range = [wvl_min, wvl_max]
+    assert len(fitter.freqs) < num_data
+    medium, rms = fitter.fit(num_tries=2)

tests/test_plugins_web.py

@@ -1,36 +1,40 @@
 import numpy as np
 
-from tidy3d.plugins import StableDispersionFitter
+from tidy3d.plugins import StableDispersionFitter, DispersionFitter
 
 
 def test_dispersion_load_list():
     """performs a fit on some random data"""
     num_data = 10
     n_data = np.random.random(num_data)
     wvls = np.linspace(1, 2, num_data)
-    fitter = StableDispersionFitter(wvls, n_data)
-
-    # num_poles = 3
-    # num_tries = 50
-    # tolerance_rms = 1e-3
-    # local_run = True
-    # best_medium, best_rms = fitter.fit(
-    #     num_tries=num_tries, num_poles=num_poles, tolerance_rms=tolerance_rms, local_run=True
-    # )
-    # print(best_rms)
-    # print(best_medium.eps_model(1e12))
+    fitter = StableDispersionFitter(wvl_um=wvls, n_data=n_data)
 
 
 def test_dispersion_load_file():
     """loads dispersion model from nk data file"""
     fitter = StableDispersionFitter.from_file("tests/data/nk_data.csv", skiprows=1, delimiter=",")
 
-    # num_poles = 3
-    # num_tries = 50
-    # tolerance_rms = 1e-3
-    # local_run = True
-    # best_medium, best_rms = fitter.fit(
-    #     num_tries=num_tries, num_poles=num_poles, tolerance_rms=tolerance_rms, local_run=True
-    # )
-    # print(best_rms)
-    # print(best_medium.eps_model(1e12))
+
+def test_dispersion_load_url():
+    """performs a fit on some random data"""
+
+    # both n and k
+    url_csv = "https://refractiveindex.info/data_csv.php?datafile=data/main/Ag/Johnson.yml"
+    url_txt = "https://refractiveindex.info/data_txt.php?datafile=data/main/Ag/Johnson.yml"
+    fitter = DispersionFitter.from_url(url_csv, delimiter=",")
+    fitter = StableDispersionFitter.from_url(url_csv, delimiter=",")
+    fitter_txt = DispersionFitter.from_url(url_txt, delimiter="\t")
+    fitter_txt = StableDispersionFitter.from_url(url_txt, delimiter="\t")
+    fitter_txt.wvl_range = [0.3, 0.8]
+    assert len(fitter_txt.freqs) < len(fitter.freqs)
+
+    # only k
+    url_csv = "https://refractiveindex.info/data_csv.php?datafile=data/main/N2/Peck-0C.yml"
+    url_txt = "https://refractiveindex.info/data_txt.php?datafile=data/main/N2/Peck-0C.yml"
+    fitter = DispersionFitter.from_url(url_csv, delimiter=",")
+    fitter_txt = DispersionFitter.from_url(url_txt, delimiter="\t")
+
+
+if __name__ == "__main__":
+    test_dispersion_load_url()

tidy3d/plugins/__init__.py

@@ -1,6 +1,6 @@
 # import the specific classes / functions needed for the plugins
 
 from .dispersion.fit import DispersionFitter
-from .dispersion.fit_web import StableDispersionFitter
+from .dispersion.fit_web import StableDispersionFitter, AdvancedFitterParam
 from .mode.mode_solver import ModeSolver
 from .near2far.near2far import Near2Far