diff --git a/Python/ml_metrics/average_precision.py b/Python/ml_metrics/average_precision.py
index e18297d..567abbd 100644
--- a/Python/ml_metrics/average_precision.py
+++ b/Python/ml_metrics/average_precision.py
@@ -22,6 +22,9 @@ def apk(actual, predicted, k=10):
             The average precision at k over the input lists
 
     """
+    if not actual:
+        return 0.0
+
     if len(predicted)>k:
         predicted = predicted[:k]
 
@@ -33,9 +36,6 @@ def apk(actual, predicted, k=10):
             num_hits += 1.0
             score += num_hits / (i+1.0)
 
-    if not actual:
-        return 0.0
-
     return score / min(len(actual), k)
 
 def mapk(actual, predicted, k=10):