Fix bug in GradientDescentTrainer when validation data is absent (#4811)

* Fix issue in GradientDescentTrainer, when validation data is absent * Prevent an error when GradientDescentTrainer is constructed with validation_data_loader=None and learning_rate_scheduler!=None * Update CHANGELOG.md * Fix issue with formatting
allenai · Nov 23, 2020 · 5b30658 · 5b30658
1 parent f353c6c
commit 5b30658
Show file tree

Hide file tree

Showing 2 changed files with 2 additions and 1 deletion.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 - Added links to source code in docs.
+- Fixed issue with GradientDescentTrainer when constructed with validation_data_loader==None and learning_rate_scheduler!=None.
 
 
 ## [v1.2.2](https://github.com/allenai/allennlp/releases/tag/v1.2.2) - 2020-11-17

diff --git a/allennlp/training/trainer.py b/allennlp/training/trainer.py
@@ -984,7 +984,7 @@ def _try_train(self) -> Dict[str, Any]:
         logger.info("Beginning training.")
 
         val_metrics: Dict[str, float] = {}
-        this_epoch_val_metric: float
+        this_epoch_val_metric: float = 0.0
         metrics: Dict[str, Any] = {}
         epochs_trained = 0
         training_start_time = time.time()