Improved calculation of normalization.

ANN_Data_Generator.py

@@ -14,6 +14,7 @@ TODO: Improve comments -> Done
 TODO: Remove unnecessary lines -> Done
 TODO: Fix bug in 'input_data' calculation -> Done
 TODO: Change order of imports -> Done
+TODO: Improve calculation of normalization -> Done
 
 """
 
@@ -274,11 +275,11 @@ class TrainingDataGenerator(object):
             Array containing normalized input data.
 
         """
-        normalized_input_data = input_data
-        for i in range(len(input_data)):
-            max_function_value = max(max(np.absolute(input_data[i])), 1)
-            normalized_input_data[i] = input_data[i] / max_function_value
-        return normalized_input_data
+        normalized_input_data = []
+        for entry in input_data:
+            max_function_value = max(max(np.absolute(entry)), 1)
+            normalized_input_data.append(entry / max_function_value)
+        return np.array(normalized_input_data)
 
     def _save_data(self, data):
         """Saves data."""