fixed issue with one parsed result

app.py

@@ -53,13 +53,20 @@ def parse_metrics_accuracy(meta):
 
 # We keep the worst case episode
 def parse_rewards(accuracy):
+    default_std = -1000
+    default_reward=-1000
     if accuracy !=  None:
-        parsed = accuracy.split(' +/- ')
-        mean_reward = float(parsed[0])
-        std_reward =  float(parsed[1])
+        parsed =  accuracy.split(' +/- ')
+        if len(parsed)>1:
+            mean_reward = float(parsed[0])
+            std_reward =  float(parsed[1])
+        else: 
+            mean_reward = default_std
+            std_reward = default_reward
+
     else:
-        mean_reward = -1000
-        std_reward = -1000
+        mean_reward = default_std
+        std_reward = default_reward
     return mean_reward, std_reward
 
 def get_data(rl_env):