Calculate route ordering is incomplete with floating point number issues

When determining the ordering of the track that has been input by the user there is some issues with the ordering of the segments of the track. This arises due to a comparison of the point locations where there is floating point number issues.

Added below is a catch term that corrects this bug by determining the distance between the end point of the segment and all possible next segments. This correction then allows for a small floating point number issue

from shapely import distance 
def order_track(df, track_points):
     """
         Order crossing points into a track along the route
         Args:
             df (DataFrame): Route info in dataframe format
             track_points (dict): Dictionary of crossing points and cell ids

         Returns:
             user_track (DataFrame): DataFrame of ordered crossing points and cell ids
     """

     start_point = Point(df.iloc[0]['Long'], df.iloc[0]['Lat'])
     end_point = Point(df.iloc[-1]['Long'], df.iloc[-1]['Lat'])

     pathing = True
     track_id = np.where(track_points['startPoints'] == start_point)[0][0]
     path_point = []
     cell_ids = []

     # Loop through crossing points to order them into a track along the route
     while pathing:
         print(track_id)
         start_point_segment = track_points['startPoints'].iloc[track_id]
         end_point_segment = track_points['endPoints'].iloc[track_id]
         path_point.append(start_point_segment)
         cell_ids.append(track_points['cellID'].iloc[track_id])

         if len(track_points['midPoints'].iloc[track_id]) != 0:
             for midpnt in track_points['midPoints'].iloc[track_id]:
                 path_point.append(midpnt)
                 cell_ids.append(track_points['cellID'].iloc[track_id])

         if  distance(end_point_segment,end_point) < 1e-10:
             pathing = False
         else:
             track_id     = np.argmin([distance(entry,end_point_segment) for entry in track_points['startPoints']])
             track_misfit = min([distance(entry,end_point_segment) for entry in track_points['startPoints']])
             if track_misfit >= 1e-10:
                 raise Exception('Path Segmentment not adding - ID={},Misfit={},distance from end={}'.format(track_id,track_misfit,distance(end_point_segment,end_point)))

     user_track = pd.DataFrame({'Point': path_point, 'CellID': cell_ids})
     return user_track

antarctica / PolarRoute

Calculate route ordering is incomplete with floating point number issues #262