How to read images from pandas column in a pytorch class

Question

I need to define a pytorch dataset class that reads the absolute path from a column to pull the image. When I try this with multiple packages, I get errors. Below are the errors for each package I'm aware of:

Pathlib.Path: TypeError: expected str, bytes or os.PathLike object, not method

glob.glob: TypeError: expected str, bytes or os.PathLike object, not method

os.path: TypeError: 'module' object is not callable

Below is my pytorch custom dataset.

class image_Dataset(Dataset):
'''
image data class    

'''
def __init__(self, data, transform = None):
    '''
    Args:
    ------------------------------------------------------------
        data = dataframe
        image = column in dataframe with absolute path to the image
        label = column in dataframe that is the target classification variable
        policy = ID variable

    '''
    self.image_frame = data
    self.transform = transform

def __len__(self):
    return len(self.image_frame)

def __getitem__(self, idx):
    if torch.is_tensor(idx):
        idx = idx.tolist()

    label = self.image_frame.iloc[idx, 16]
    pic = Path(self.image_frame.iloc[idx,19])
    img = Image.open(pic)
    policy = self.image_frame.iloc[idx, 1]
    sample = {'image': img, 'policy': policy, 'label':label}

    if self.transform:
        image = self.transform(image)

    return image, label, policy

path column in my dataset values looks like the following:

D:/Models/Photos/Train/train_img.jpg Full trace back below:

IndexError                                Traceback (most recent call last)
<ipython-input-261-38143c041795> in <module>
      7 
      8 for i in range(len(roof_data_test)):
----> 9     sample = roof_data_test[i]
     10 
     11     print(i, sample[0].shape, sample[1], sample[2])

<ipython-input-260-1bd25b938fea> in __getitem__(self, idx)
     25 
     26         label = self.image_frame.iloc[idx, 16]
---> 27         pic = Path(self.image_frame.iloc[idx,19])
     28         img = Image.open(pic)
     29         policy = self.image_frame.iloc[idx, 1]

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\indexing.py in __getitem__(self, key)
   1492             except (KeyError, IndexError, AttributeError):
   1493                 pass
-> 1494             return self._getitem_tuple(key)
   1495         else:
   1496             # we by definition only have the 0th axis

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\indexing.py in _getitem_tuple(self, tup)
   2141     def _getitem_tuple(self, tup):
   2142 
-> 2143         self._has_valid_tuple(tup)
   2144         try:
   2145             return self._getitem_lowerdim(tup)

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\indexing.py in _has_valid_tuple(self, key)
    221                 raise IndexingError('Too many indexers')
    222             try:
--> 223                 self._validate_key(k, i)
    224             except ValueError:
    225                 raise ValueError("Location based indexing can only have "

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\indexing.py in _validate_key(self, key, axis)
   2068             return
   2069         elif is_integer(key):
-> 2070             self._validate_integer(key, axis)
   2071         elif isinstance(key, tuple):
   2072             # a tuple should already have been caught by this point

C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\indexing.py in _validate_integer(self, key, axis)
   2137         len_axis = len(self.obj._get_axis(axis))
   2138         if key >= len_axis or key < -len_axis:
-> 2139             raise IndexError("single positional indexer is out-of-bounds")
   2140 
   2141     def _getitem_tuple(self, tup):

IndexError: single positional indexer is out-of-bounds

Answer 1

single positional indexer is out-of-bounds is telling you that your are trying to access a column that is not there. Make sure that the columns you are trying to access exist