switch at_task_boundary to private and add before arg to detect one s…

…ide of the boundary or another

avalanche/training/templates/observation_type/batch_observation.py

@@ -8,7 +8,7 @@
 from avalanche.models.utils import avalanche_model_adaptation
 from avalanche.training.templates.strategy_mixin_protocol import SGDStrategyProtocol
 from avalanche.models.dynamic_optimizers import reset_optimizer, update_optimizer
-from avalanche.training.utils import at_task_boundary
+from avalanche.training.utils import _at_task_boundary
 
 
 class BatchObservation(SGDStrategyProtocol):
@@ -73,7 +73,7 @@ def check_model_and_optimizer(self, reset_optimizer_state=False, **kwargs):
         if self.optimized_param_id is None:
             self.make_optimizer(reset_optimizer_state=True, **kwargs)
 
-        if at_task_boundary(self.experience):
+        if _at_task_boundary(self.experience, before=True):
             self.model = self.model_adaptation()
             self.make_optimizer(reset_optimizer_state=reset_optimizer_state, **kwargs)
 

avalanche/training/utils.py

@@ -26,7 +26,7 @@
 from avalanche.models.batch_renorm import BatchRenorm2D
 
 
-def at_task_boundary(training_experience) -> bool:
+def _at_task_boundary(training_experience, before=True) -> bool:
     """
     Given a training experience,
     returns true if the experience is at the task boundary
@@ -41,14 +41,17 @@ def at_task_boundary(training_experience) -> bool:
 
     - If the experience is not an online experience, returns True
 
+    :param before: If used in before_training_exp, 
+                   set to True, otherwise set 
+                   to False
+
     """
 
     if isinstance(training_experience, OnlineCLExperience):
         if training_experience.access_task_boundaries:
-            if (
-                training_experience.is_first_subexp
-                or training_experience.is_last_subexp
-            ):
+            if before and training_experience.is_first_subexp:
+                return True
+            elif (not before) and training_experience.is_last_subexp:
                 return True
         else:
             return True
@@ -484,5 +487,4 @@ def __str__(self):
     "examples_per_class",
     "ParamData",
     "cycle",
-    "at_task_boundary",
 ]