add tests to select features

tests/test_functionality.py

@@ -18,7 +18,7 @@
     StandardNormalVariate,
 )
 from chemotools.smooth import MeanFilter, MedianFilter, WhittakerSmooth
-from chemotools.variable_selection import RangeCut
+from chemotools.variable_selection import RangeCut, SelectFeatures
 from tests.fixtures import (
     spectrum,
     spectrum_arpls,
@@ -439,8 +439,8 @@ def test_point_scaler(spectrum):
 
 def test_point_scaler_with_wavenumbers():
     # Arrange
-    wavenumbers = np.array([1., 2., 3., 4., 5., 6., 7., 8., 9., 10.])
-    spectrum = np.array([[10., 12., 14., 16., 14., 12., 10., 12., 14., 16.]])
+    wavenumbers = np.array([1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0])
+    spectrum = np.array([[10.0, 12.0, 14.0, 16.0, 14.0, 12.0, 10.0, 12.0, 14.0, 16.0]])
 
     # Act
     index_scaler = PointScaler(point=4, wavenumbers=wavenumbers)
@@ -450,7 +450,6 @@ def test_point_scaler_with_wavenumbers():
     assert np.allclose(spectrum_corrected[0], spectrum[0] / spectrum[0][3], atol=1e-8)
 
 
-
 def test_range_cut_by_index(spectrum):
     # Arrange
     range_cut = RangeCut(start=0, end=10)
@@ -544,6 +543,35 @@ def test_saviszky_golay_filter_3():
     assert np.allclose(spectrum_corrected[0], np.ones((1, 10)), atol=1e-2)
 
 
+def test_select_features():
+    # Arrange
+    spectrum = np.array([[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]])
+    expected = np.array([[1, 2, 3, 8, 9, 10]])
+
+    # Act
+    select_features = SelectFeatures(features=np.array([0, 1, 2, 7, 8, 9]))
+    spectrum_corrected = select_features.fit_transform(spectrum)
+
+    # Assert
+    assert np.allclose(spectrum_corrected[0], expected, atol=1e-8)
+
+
+def test_select_features_with_wavenumbers():
+    # Arrange
+    wavenumbers = np.array([1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0])
+    spectrum = np.array([[1.0, 2.0, 3.0, 5.0, 8.0, 13.0, 21.0, 34.0, 55.0, 89.0]])
+    expected = np.array([[1.0, 2.0, 3.0, 34.0, 55.0, 89.0]])
+
+    # Act
+    select_features = SelectFeatures(
+        features=np.array([1, 2, 3, 8, 9, 10]), wavenumbers=wavenumbers
+    )
+    spectrum_corrected = select_features.fit_transform(spectrum)
+
+    # Assert
+    assert np.allclose(spectrum_corrected[0], expected, atol=1e-8)
+
+
 def test_standard_normal_variate(spectrum, reference_snv):
     # Arrange
     snv = StandardNormalVariate()

tests/test_sklearn_compliance.py

@@ -24,7 +24,7 @@
     SavitzkyGolayFilter,
     WhittakerSmooth,
 )
-from chemotools.variable_selection import RangeCut
+from chemotools.variable_selection import RangeCut, SelectFeatures
 
 from tests.fixtures import spectrum
 
@@ -173,6 +173,14 @@ def test_compliance_savitzky_golay_filter():
     check_estimator(transformer)
 
 
+# SelectFeatures
+def test_compliance_select_features():
+    # Arrange
+    transformer = SelectFeatures()
+    # Act & Assert
+    check_estimator(transformer)
+
+
 # StandardNormalVariate
 def test_compliance_standard_normal_variate():
     # Arrange