Merge pull request #12 from k1th/master

fixes #11

Author: anitagraser

qgis_processing/qgisUtils.py

@@ -53,6 +53,8 @@ def trajectories_from_qgis_point_layer(layer, time_field_name, trajectory_id_fie
     df_by_id = dict(tuple(geo_df.groupby(trajectory_id_field)))
     trajectories = []
     for key, value in df_by_id.items():
+        if len(value) < 2:
+            continue
         traj = Trajectory(key, value)
         trajectories.append(traj)
     return trajectories

trajectory.py

@@ -177,6 +177,8 @@ def split(self, mode='daybreak'):
         if mode == 'daybreak':
             dfs = [group[1] for group in self.df.groupby(self.df.index.date)]
             for i, df in enumerate(dfs):
+                if len(df) < 2:
+                    continue
                 result.append(Trajectory('{}_{}'.format(self.id, i), df))
         else:
             raise ValueError('Invalid split mode {}. Must be one of [daybreak]'.format(mode))