diff --git a/cost_function.py b/cost_function.py
index 8fbe63f38f782c3655c6d86ee537aa95f6f7df12..859cac62c3f07e11b53071485cb1163c7181c8b9 100755
--- a/cost_function.py
+++ b/cost_function.py
@@ -244,13 +244,13 @@ for n in g.vertices():
 for edge in g.edges():
     source_node = edge.source()
     target_node = edge.target()
-    
+
     cf = -10000
 
-    lat_for_conv = (g.vp.pos_last[source_node][1] + 
+    lat_for_conv = (g.vp.pos_last[source_node][1] +
                     g.vp.pos_first[target_node][1]) / 2 # latitude needed for conversion of degrees to kilometers
     lat_for_conv = math.radians(lat_for_conv) # need to convert to radians
-    
+
     # because of the wrapping issue (360° wrapping incorrectly to 0°), we check for that here
     lon_diff = abs(g.vp.pos_last[source_node][0] - g.vp.pos_first[target_node][0])
     if (lon_diff > 300):
@@ -258,38 +258,38 @@ for edge in g.edges():
 
     # calculate Delta_cent: numbers used for conversion obtained from:
         # https://stackoverflow.com/questions/1253499/simple-calculations-for-working-with-lat-lon-and-km-distance
-    Delta_Cent = math.sqrt((  lon_diff * 111.32 * math.cos(lat_for_conv)   )**2 + 
+    Delta_Cent = math.sqrt((  lon_diff * 111.32 * math.cos(lat_for_conv)   )**2 +
                            (   (g.vp.pos_last[source_node][1] - g.vp.pos_first[target_node][1]) * 110.574  )**2)
-    
+
     # calculate the first term
     first_term = ((Delta_Cent - delta_cent_mean)/delta_cent_std) ** 2
-    
-    # Rossbies: 
+
+    # Rossbies:
     if (g.vp.first_av_ros[target_node] and g.vp.last_av_ros[source_node]):
         Delta_Ro = g.vp.last_av_ros[source_node] - g.vp.first_av_ros[target_node]
     else:
         print("At least one of the rossbies is invalid.")
         #Delta_Ro = delta_ro_mean
         Delta_Ro = 0
-    
+
     # Calculate the second term
     second_term = ((Delta_Ro - delta_ro_mean)/delta_ro_std ) ** 2
-    
+
     # R_Vmax 1 and 2 already exist, just get the delta
-    
+
     Delta_R_Vmax = g.vp.last_av_rad[source_node] - g.vp.first_av_rad[target_node]
-    
+
     # Calculate the third term
     third_term = ((Delta_R_Vmax - delta_r_mean)/delta_r_std) ** 2
-    
+
     #############################
     # calculate the cost function
     #############################
-    
+
     cf = math.sqrt(first_term + second_term + third_term)
-    
+
     # assign as weight to the edge
-    g.ep.nl_cost_function[edge] = cf    
+    g.ep.nl_cost_function[edge] = cf
 
 
 ################################