Learn.get_preds() error for multi label: 'MultiCategoryList' object has no attribute 'dl'

Part 1 (2019) Advanced (Part 1 v3)
1

Hi,

I am trying to practice multi label classification.
for that i have a csv file and train and test folders with images.
Then I do a normal training that works well:

src = (ImageItemList.from_csv(path, 'train.csv', folder='train', suffix='_green.png', test='test')
      .random_split_by_pct(0.2)
      .label_from_df(sep=' '))
data = (src.transform(tfms, size=128).databunch().normalize(imagenet_stats))
acc_02 = partial(accuracy_thresh, thresh=0.2)
f_score = partial(fbeta, thresh=0.2)
learn = create_cnn(data, arch, metrics=[acc_02, f_score])

Then I do

learn.fit_one_cycle(5, slice(lr))

and then I am trying to predict for my test data:

preds,y,losses = learn.get_preds(ds_type=DatasetType.Test, with_loss=True)

AttributeError Traceback (most recent call last)
in ()
----> 1 preds,y,losses = learn.get_preds(ds_type=DatasetType.Test, with_loss=True)

~/anaconda3/lib/python3.6/site-packages/fastai/basic_train.py in get_preds(self, ds_type, with_loss, n_batch, pbar)
210 “Return predictions and targets on the valid, train, or test set, depending on ds_type.”
211 lf = self.loss_func if with_loss else None
→ 212 return get_preds(self.model, self.dl(ds_type), cb_handler=CallbackHandler(self.callbacks),
213 activ=_loss_func2activ(self.loss_func), loss_func=lf, n_batch=n_batch, pbar=pbar)
214

~/anaconda3/lib/python3.6/site-packages/fastai/basic_train.py in dl(self, ds_type)
197 def dl(self, ds_type:DatasetType=DatasetType.Valid):
198 “Return DataLoader for DatasetType ds_type.”
→ 199 return self.data.dl(ds_type)
200
201 def load(self, name:PathOrStr, device:torch.device=None, strict:bool=True):

~/anaconda3/lib/python3.6/site-packages/fastai/data_block.py in getattr(self, k)
339
340 def getattr(self, k):
→ 341 ft = getattr(self.train, k)
342 if not isinstance(ft, Callable): return ft
343 fv = getattr(self.valid, k)

~/anaconda3/lib/python3.6/site-packages/fastai/data_block.py in getattr(self, k)
441 def getattr(self,k:str)->Any:
442 res = getattr(self.x, k, None)
→ 443 return res if res is not None else getattr(self.y, k)
444
445 def getitem(self,idxs:Union[int,np.ndarray])->‘LabelList’:

AttributeError: ‘MultiCategoryList’ object has no attribute ‘dl’

I’ve search the forum but could not find the reason for that. What I am doing wrong?

2 Likes
2

I am just guessing …

You cannot get the loss of the predictions since you don’t know their real value (Test set you never know the answer).

I guess if you change

ds_type=DatasetType.Test
for
ds_type=DatasetType.Valid
it will run fine.

Otherwise set
with_loss=False