datablock_label.py

---------------------------------------------------------------------------
IndexError                                Traceback (most recent call last)
<ipython-input-65-a21b1f7faa1d> in <module>
      2 src = (ImageItemList.from_df(df=train_df, path=path, cols='Name', folder='train')
      3        .split_by_valid_func(lambda o: o in val_n)
----> 4        .label_from_df(cols='Id'))

/opt/anaconda3/lib/python3.6/site-packages/fastai/data_block.py in _inner(*args, **kwargs)
    346             self.train = ft(*args, **kwargs)
    347             assert isinstance(self.train, LabelList)
--> 348             self.valid = fv(*args, **kwargs)
    349             self.__class__ = LabelLists
    350             self.process()

/opt/anaconda3/lib/python3.6/site-packages/fastai/data_block.py in label_from_df(self, cols, **kwargs)
    199         "Label `self.items` from the values in `cols` in `self.xtra`."
    200         labels = _maybe_squeeze(self.xtra.iloc[:,df_names_to_idx(cols, self.xtra)])
--> 201         return self.label_from_list(labels, **kwargs)
    202 
    203     def label_const(self, const:Any=0, **kwargs)->'LabelList':

/opt/anaconda3/lib/python3.6/site-packages/fastai/data_block.py in label_from_list(self, labels, **kwargs)
    191         "Label `self.items` with `labels` using `label_cls`"
    192         labels = array(labels, dtype=object)
--> 193         label_cls = self.get_label_cls(labels, **kwargs)
    194         y = label_cls(labels, path=self.path, **kwargs)
    195         res = self._label_list(x=self, y=y)

/opt/anaconda3/lib/python3.6/site-packages/fastai/data_block.py in get_label_cls(self, labels, label_cls, sep, **kwargs)
    181         if label_cls is not None:               return label_cls
    182         if self.label_cls is not None:          return self.label_cls
--> 183         it = index_row(labels,0)
    184         if sep is not None:                     return MultiCategoryList
    185         if isinstance(it, (float, np.float32)): return FloatList

/opt/anaconda3/lib/python3.6/site-packages/fastai/core.py in index_row(a, idxs)
    207         if isinstance(res,(pd.DataFrame,pd.Series)): return res.copy()
    208         return res
--> 209     return a[idxs]
    210 
    211 def func_args(func)->bool:

IndexError: index 0 is out of bounds for axis 0 with size 0