Bug when trajs has dissapearing peaks

[hadim]

true_trajs = data.brownian_trajectories_generator(p_disapear=0.1)
#true_trajs = data.brownian_trajs_df()

solver = ByFrameSolver.for_brownian_motion(true_trajs, max_speed=5)
trajs = solver.track(progress_bar=False)

---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
<ipython-input-81-49ddb70622eb> in <module>()
      3 
      4 solver = ByFrameSolver.for_brownian_motion(true_trajs, max_speed=5)
----> 5 trajs = solver.track(progress_bar=False)

/home/hadim/Insync/Documents/phd/dev/scikit-tracker/sktracker/tracker/solver/by_frame_solver.py in track(self, progress_bar, progress_bar_out)
     96                 print_progress(progress, message=message, out=progress_bar_out)
     97 
---> 98             self.one_frame(t_in, t_out)
     99 
    100         if progress_bar:

/home/hadim/Insync/Documents/phd/dev/scikit-tracker/sktracker/tracker/solver/by_frame_solver.py in one_frame(self, t_in, t_out)
    119         pos_out = self.pos_out
    120 
--> 121         self.link_block = LinkBlock(pos_in, pos_out, self.link_cf)
    122         self.birth_block = DiagBlock(pos_out, self.birth_cf)
    123         self.death_block = DiagBlock(pos_in, self.death_cf)

/home/hadim/Insync/Documents/phd/dev/scikit-tracker/sktracker/tracker/matrices/matrices.py in __init__(self, objects_in, objects_out, cost_function)
    244         self.mat = None
    245 
--> 246         self._build()
    247 
    248     def _build(self):

/home/hadim/Insync/Documents/phd/dev/scikit-tracker/sktracker/tracker/matrices/matrices.py in _build(self)
    250         """
    251 
--> 252         self.mat = self.cost_function.build(self.objects_in, self.objects_out)
    253 
    254         if self.mat.shape != (len(self.objects_in),

/home/hadim/Insync/Documents/phd/dev/scikit-tracker/sktracker/tracker/cost_function/brownian.py in build(self, pos_in, pos_out)
     62                           pos_out[coords].astype(np.float),
     63                           metric=distance_metric)
---> 64         dt = pos_out['t'][0] - pos_in['t'][0]
     65         distances /= dt
     66         distances[distances > max_speed] = np.nan

/home/hadim/.virtualenvs/st/lib/python3.3/site-packages/pandas/core/series.py in __getitem__(self, key)
    489     def __getitem__(self, key):
    490         try:
--> 491             result = self.index.get_value(self, key)
    492             if isinstance(result, np.ndarray):
    493                 return self._constructor(result,index=[key]*len(result)).__finalize__(self)

/home/hadim/.virtualenvs/st/lib/python3.3/site-packages/pandas/core/index.py in get_value(self, series, key)
   1030 
   1031         try:
-> 1032             return self._engine.get_value(s, k)
   1033         except KeyError as e1:
   1034             if len(self) > 0 and self.inferred_type == 'integer':

/home/hadim/.virtualenvs/st/lib/python3.3/site-packages/pandas/index.cpython-33m.so in pandas.index.IndexEngine.get_value (pandas/index.c:2661)()

/home/hadim/.virtualenvs/st/lib/python3.3/site-packages/pandas/index.cpython-33m.so in pandas.index.IndexEngine.get_value (pandas/index.c:2476)()

/home/hadim/.virtualenvs/st/lib/python3.3/site-packages/pandas/index.cpython-33m.so in pandas.index.IndexEngine.get_loc (pandas/index.c:3215)()

/home/hadim/.virtualenvs/st/lib/python3.3/site-packages/pandas/hashtable.cpython-33m.so in pandas.hashtable.Int64HashTable.get_item (pandas/hashtable.c:6450)()

/home/hadim/.virtualenvs/st/lib/python3.3/site-packages/pandas/hashtable.cpython-33m.so in pandas.hashtable.Int64HashTable.get_item (pandas/hashtable.c:6394)()

KeyError: 0

[glyg]

Try to isolate and reproduce the bug. Then ask on stackoverflow what could cause this.