[change] Quality class determination documentation improvement

Also change order of expected/actual values in test assert methods to improve output of test function.
The first parameter is supposed to be the expected value, the second one the actual result.

pylot/core/pick/utils.py

@@ -1288,6 +1288,7 @@ def get_quality_class(uncertainty, weight_classes):
         quality = next(i for i, v in enumerate(weight_classes) if v >= uncertainty)
     except StopIteration:
         # raised when uncertainty is larger than all values in weight_classes
+        # set quality to max possible value
         quality = len(weight_classes)
     return quality
 

tests/test_get_quality_class.py

@@ -5,6 +5,12 @@ from pylot.core.pick.utils import get_quality_class
 class TestQualityClassFromUncertainty(unittest.TestCase):
     """
     Test function that assigns a quality value [0...4] to a pick uncertainty.
+    The pick uncertainty is compared to the error classes.
+    A pick uncertainty that is below the first error class is assigned the best quality, quality 0.
+    A pick uncertainty that is above the first error class but below the second is assigned quality 1 and so on.
+    A pick uncertainty that is larger than the biggest error class is assigned quality 4.
+    The upper border of a quality class is inclusive, the lower border exclusive. Meaning if a value is exactly on the
+    border between two classes, it is assigned into the higher quality class (represented by the lower number).
     """
 
     def setUp(self):
@@ -14,37 +20,37 @@ class TestQualityClassFromUncertainty(unittest.TestCase):
 
     def test_out_of_lower_bound(self):
         # Error out of lower bound of classes
-        self.assertEqual(get_quality_class(0.5, self.error_classes), 0)
+        self.assertEqual(0, get_quality_class(0.5, self.error_classes))
 
     def test_out_of_upper_bound(self):
         # Error out of upper bound of error classes
-        self.assertEqual(get_quality_class(14.7, self.error_classes), 4)
+        self.assertEqual(4, get_quality_class(14.7, self.error_classes))
 
     def test_on_lower_border(self):
         # Error exactly on lower bound
-        self.assertEqual(get_quality_class(1., self.error_classes), 0)
+        self.assertEqual(0, get_quality_class(1., self.error_classes))
 
     def test_on_upper_border(self):
         # Error exactly on upper bound
-        self.assertEqual(get_quality_class(7., self.error_classes), 3)
+        self.assertEqual(3, get_quality_class(7., self.error_classes))
 
     def test_on_middle_border_inclusive(self):
         # Error exactly between two classes, since lower bound is exclusive and upper bound is inclusive it should
         # fall into the class with better quality
-        self.assertEqual(get_quality_class(3., self.error_classes), 1)
-        self.assertNotEqual(get_quality_class(3., self.error_classes), 2)
+        self.assertEqual(1, get_quality_class(3., self.error_classes))
+        self.assertNotEqual(2, get_quality_class(3., self.error_classes))
 
-    def test_in_class0(self):
+    def test_in_class1(self):
         # Error exactly in class 1
-        self.assertEqual(get_quality_class(1.5, self.error_classes), 1)
+        self.assertEqual(1, get_quality_class(1.5, self.error_classes))
 
     def test_in_class2(self):
         # Error exactly in class 2
-        self.assertEqual(get_quality_class(3.5, self.error_classes), 2)
+        self.assertEqual(2, get_quality_class(3.5, self.error_classes))
 
     def test_in_class3(self):
         # Error exactly in class 3
-        self.assertEqual(get_quality_class(5.6, self.error_classes), 3)
+        self.assertEqual(3, get_quality_class(5.6, self.error_classes))
 
 if __name__ == '__main__':
     unittest.main()