diff --git a/Trajectories/cost_function.py b/Trajectories/cost_function.py
index 58f0a782b4bcd6e4f27bbacaa4192d1a720d432a..0c57a5b98bda711eb727013ae46462fcdc876aa1 100755
--- a/Trajectories/cost_function.py
+++ b/Trajectories/cost_function.py
@@ -26,7 +26,7 @@ import graph_tool
 
 import util_eddies
 
-Omega = 2 * math.pi / 86164.0
+Omega = 2 * math.pi / 86164.0  # in s-1
 r_Earth = 6371  # radius of the Earth, in km
 
 
@@ -55,8 +55,10 @@ def calculate_radii_rossby(properties):
         avg_rad += radius  # in m
 
     avg_rad /= len(properties)
+
     if n_valid_Rossby != 0:
         avg_Rossby /= n_valid_Rossby
+
     return avg_rad, avg_Rossby
 
 
@@ -109,13 +111,13 @@ parser.add_argument("SHPC_dir")
 parser.add_argument("orientation", choices=["Anticyclones", "Cyclones"])
 parser.add_argument(
     "input_segments",
-    help="input graph of segments without "
-    "cost, suffix .gt (graph-tool) or .graphml",
+    help="input graph of segments without cost, suffix .gt (graph-tool) or "
+    ".graphml",
 )
 parser.add_argument(
     "output_segments",
-    help="output graph of segments with "
-    "cost, suffix .gt (graph-tool) or .graphml",
+    help="output graph of segments with cost, suffix .gt (graph-tool) or "
+    ".graphml",
 )
 parser.add_argument(
     "--debug", help="save properties to output file", action="store_true"
@@ -124,11 +126,11 @@ args = parser.parse_args()
 
 # Set some values needed for the cost function:
 delta_cent_mean = 3.8481  # in km
-delta_cent_std = 8.0388
+delta_cent_std = 8.0388  # in km
 delta_ro_mean = -0.0025965
 delta_ro_std = 5.2168
 delta_r_mean = -9.4709  # in m
-delta_r_std = 8.6953e3
+delta_r_std = 8.6953e3  # in m
 
 # Load the graph_tool file: