diff --git a/Search-based Planning/.idea/workspace.xml b/Search-based Planning/.idea/workspace.xml
index 134462b..9d3bff3 100644
--- a/Search-based Planning/.idea/workspace.xml	
+++ b/Search-based Planning/.idea/workspace.xml	
@@ -2,7 +2,7 @@
 <project version="4">
   <component name="ChangeListManager">
     <list default="true" id="025aff36-a6aa-4945-ab7e-b2c625055f47" name="Default Changelist" comment="">
-      <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/../Stochastic Shortest Path/value_iteration.py" beforeDir="false" afterPath="$PROJECT_DIR$/../Stochastic Shortest Path/value_iteration.py" afterDir="false" />
     </list>
     <option name="EXCLUDED_CONVERTED_TO_IGNORED" value="true" />
     <option name="SHOW_DIALOG" value="false" />
diff --git a/Stochastic Shortest Path/gif/VI.gif b/Stochastic Shortest Path/gif/VI.gif
index e5a952a..b45ce7d 100644
Binary files a/Stochastic Shortest Path/gif/VI.gif and b/Stochastic Shortest Path/gif/VI.gif differ
diff --git a/Stochastic Shortest Path/gif/VI.jpeg b/Stochastic Shortest Path/gif/VI.jpeg
index 191b615..72ae985 100644
Binary files a/Stochastic Shortest Path/gif/VI.jpeg and b/Stochastic Shortest Path/gif/VI.jpeg differ
diff --git a/Stochastic Shortest Path/value_iteration.py b/Stochastic Shortest Path/value_iteration.py
index 7fb77d8..46b2656 100644
--- a/Stochastic Shortest Path/value_iteration.py	
+++ b/Stochastic Shortest Path/value_iteration.py	
@@ -21,9 +21,8 @@ class Value_iteration:
         self.gamma = 0.9                                       # discount factor
         self.obs = env.obs_map()                               # position of obstacles
         self.lose = env.lose_map()                             # position of lose states
-        self.name1 = "value_iteration, e=" + str(self.e) \
-                     + ", gamma=" + str(self.gamma)
-        self.name2 = "convergence of error, e=" + str(self.e)
+        self.name1 = "value_iteration, gamma=" + str(self.gamma)
+        self.name2 = "converge process, e=" + str(self.e)
 
 
     def iteration(self):
@@ -114,6 +113,7 @@ class Value_iteration:
         plt.plot(diff, color='#808080', marker='o')
         plt.title(self.name2, fontdict=None)
         plt.xlabel('iterations')
+        plt.ylabel('difference of successive iterations')
         plt.grid('on')
         plt.show()