Added observers for tracking data

spatz/simulation.py

@@ -8,6 +8,7 @@ from spatz.sensors import Sensor
 from spatz.dataset import Dataset
 from spatz.logger import Logger
 from spatz.sensors import Sensor
+from spatz.observer import Observer
 
 
 class UniformTimeSteps:
@@ -89,11 +90,34 @@ class Simulation:
         return self
 
     def add_sensor(self, sensor, *args, **kwargs) -> Sensor:
+        """Register a new sensor for this simulation. A registered sensor can be called like a function and returns
+        the current measurements. The class' constructor arguments have to be given aswell.
+
+        Args:
+            sensor (_type_): A subclass of the abstract Sensor class.
+
+        Returns:
+            Sensor: Returns an object of the provided sensor subclass.
+        """
         assert issubclass(sensor, Sensor), "Expected a subclass of Sensor."
 
         self.__sensors.append(sensor(self.__dataset, self.__logger, *args, **kwargs))
 
         return self.__sensors[-1]
-        
+    
+    def add_observer(self, attributes: List[str]) -> Observer:
+        """Register a new observer for this simulation observing the provided attributes.
+
+        Args:
+            attributes (List[str]): A list of strings describing the attributes to observe.
+
+        Returns:
+            Observer: An observer object which can be called like a function to obtain the desired data.
+        """
+        assert len(attributes) != 0, "Observed attributes list must be nonempty."
+
+        self.__sensors.append(Observer(self.__dataset, self.__logger, attributes))
+
+        return self.__sensors[-1]