diff --git a/Trajectories/plot_traj.py b/Trajectories/plot_traj.py
index 3b8392e5aad11268ae1cc95cefe09ace4cc0d504..c38c79aa5850cdcde5a0e3d0ab46489bcb229635 100755
--- a/Trajectories/plot_traj.py
+++ b/Trajectories/plot_traj.py
@@ -4,6 +4,11 @@ import report_graph
 import random
 
 def get_extr_coord(traj, e_overestim, SHPC, orientation):
+    """Get the coordinates of the extrema of instantaneous eddies along a
+    given trajectory.
+
+    """
+
     x = []
     y = []
 
@@ -50,7 +55,7 @@ if __name__ == "__main__":
     parser.add_argument("--annotate", action = "store_true", help = "annotate "
                         "the first point of trajectory with node number")
     parser.add_argument("--min_duration", type = int, default = 1,
-                        help = "minimumduration of plotted trajectories (in "
+                        help = "minimum duration of plotted trajectories (in "
                         "time steps), >= 1")
     args = parser.parse_args()