Fix for wollam data without dpolE (#214)

* Fix for wollam data without dpolE

* Use union typing to support older py versions

* Fix `as_index()` and `as_dielectric()`

* Add test to check if values stay the same after dispersion conversion

* Remove `as_dielectric()`

* Fix tests

* Set rep and single params

* Remove unecessary import

* Update changelog

---------

Co-authored-by: MarJMue <[email protected]>

Author: domna

CHANGELOG.md

@@ -1,5 +1,12 @@
 # Changelog
 
+## Version 0.22.4
+
+### Bugfixes
+
+- Fix for an error when copying of an IndexDispersion created from a Dispersion
+- Fix for reading of woollam data if no dpolE is present
+
 ## Version 0.22.3
 
 ### Bugfixes

src/elli/dispersions/base_dispersion.py

@@ -2,7 +2,6 @@
 """Abstract base class and utility classes for pyElli dispersion"""
 
 from abc import ABC, abstractmethod
-from copy import deepcopy
 from typing import List, Optional, Union
 
 import numpy as np
@@ -239,15 +238,25 @@ def as_index(self):
         Please ensure that you know what you are doing as building dielectric
         and index based dispersions is normally mathematically wrong.
         """
-        index_class = deepcopy(self)
-        # pylint: disable=attribute-defined-outside-init
-        index_class.refractive_index = lambda lbda: sqrt(
-            index_class.dielectric_function(lbda)
+
+        AnonymousIndexDispersion = type(
+            "AnonymousIndexDispersion",
+            (IndexDispersion,),
+            {
+                "rep_params_template": self.rep_params_template,
+                "single_params_template": self.single_params_template,
+                "dielectric_function": self.dielectric_function,
+                "refractive_index": lambda self, lbda: sqrt(
+                    self.dielectric_function(lbda)
+                ),
+            },
         )
-        index_class.__class__ = IndexDispersion  # pylint: disable=invalid-name
-        index_class.dielectric_function = self.dielectric_function
 
-        return index_class
+        idx_dispersion = AnonymousIndexDispersion()
+        idx_dispersion.rep_params = self.rep_params
+        idx_dispersion.single_params = self.single_params
+
+        return idx_dispersion
 
 
 class IndexDispersion(BaseDispersion):
@@ -301,18 +310,6 @@ def __add__(
     def dielectric_function(self, lbda: npt.ArrayLike) -> npt.NDArray:
         return self.refractive_index(lbda) ** 2
 
-    def as_dielectric(self):
-        """
-        Returns this class as Dispersion.
-        This method may be used to add dielectric and index based dispersions.
-        Please ensure that you know what you are doing as building dielectric
-        and index based dispersions is normally mathematically wrong.
-        """
-        diel_disp = deepcopy(self)
-        diel_disp.__class__ = Dispersion  # pylint: disable=invalid-name
-        diel_disp.dielectric_function = self.dielectric_function
-        return diel_disp
-
 
 class DispersionFactory:
     """A factory class for dispersion objects"""

src/elli/importer/woollam.py

@@ -5,7 +5,7 @@
 
 import logging
 import re
-from typing import TextIO
+from typing import TextIO, Union
 
 import pandas as pd
 from pint import DimensionalityError, UndefinedUnitError
@@ -20,7 +20,7 @@
 is_float_regex = re.compile(r"[+-]?(\d+([.]\d*)?([eE][+-]?\d+)?|[.]\d+([eE][+-]?\d+)?)")
 
 
-def is_float(line: str) -> bool:
+def is_float(line: Union[float, int, str]) -> bool:
     """Checks whether the given line is a float
 
     Args:
@@ -29,7 +29,11 @@ def is_float(line: str) -> bool:
     Returns:
         bool: True if it is a float, False otherwise
     """
-    return bool(is_float_regex.search(line))
+    if isinstance(line, (float, int)):
+        return True
+    if isinstance(line, str):
+        return bool(is_float_regex.search(line))
+    return False
 
 
 def _is_wvase_tabular(line: str) -> bool:
@@ -126,7 +130,7 @@ def _read_wvase_dataframe(file_object: TextIO) -> pd.DataFrame:
         header=None,
         names=["Wavelength", "Angle of Incidence", "Ψ", "Δ", "Ψ_err", "Δ_err"],
     )
-    print(dframe)
+
     dframe = (
         dframe[dframe.apply(lambda x: is_float(x.iloc[0]), axis=1)]
         .set_index(["Wavelength", "Angle of Incidence"])

tests/test_dispersions.py

@@ -1,6 +1,7 @@
 """Tests for dispersion models"""
 
 import os
+from copy import deepcopy
 from shutil import copytree, rmtree
 
 import numpy as np
@@ -11,6 +12,7 @@
 
 import elli
 from elli.dispersions.base_dispersion import InvalidParameters
+from elli.dispersions.sellmeier import Sellmeier
 
 
 @fixture
@@ -233,3 +235,38 @@ def test_correct_reconstruction_with_pseudo_dielectric():
         ).get_dielectric_df(check_lbda),
         gaussian.get_dielectric_df(check_lbda),
     )
+
+
+def test_deepcopy_of_index_dispersion():
+    sell = Sellmeier()
+    sell.add(1, 1)
+
+    deepcopy(sell.as_index())
+
+
+def test_index_dispersion_conversion():
+    sell = Sellmeier()
+    sell.add(1, 1)
+
+    lbda = np.linspace(300, 900, 100)
+
+    assert_array_equal(
+        sell.as_index().get_dielectric(lbda),
+        sell.get_dielectric(lbda),
+    )
+
+    assert_array_equal(
+        sell.as_index().add(2, 2).get_dielectric(lbda), sell.get_dielectric(lbda)
+    )
+
+
+def test_dispersion_conversion_to_other_type():
+    lbda = np.linspace(300, 900, 100)
+    RII = elli.db.RII()
+
+    disp = RII.get_dispersion("AgCl", "Tilton")
+
+    assert_array_equal(
+        disp.as_index().get_dielectric(lbda),
+        disp.get_dielectric(lbda),
+    )

tests/test_wollam.py

@@ -2,16 +2,21 @@
 
 import pytest
 from fixtures import datadir  # pylint: disable=unused-import
+
 import elli
 
 
 # pylint: disable=redefined-outer-name
 def test_reading_of_psi_delta_woollam(datadir):
     """Psi/delta Spectraray file is read w/o errors"""
     data_wvase = elli.read_woollam_psi_delta(datadir / "wvase_example.dat")
+    data_wvase_wo_dpolE = elli.read_woollam_psi_delta(
+        datadir / "wvase_example_wo_dpolE.dat"
+    )
     data_cease = elli.read_woollam_psi_delta(datadir / "complete_ease_example.dat")
 
     assert data_wvase.shape == (542, 2)
+    assert data_wvase_wo_dpolE.shape == (542, 2)
     assert data_cease.shape == (3263, 2)