PyTorch 1.5 not working with fastai

username: Nick_Corona
cooked: <p>I get this stack trace when trying to run this command from the first lesson’s juptyer notebook.</p>
<pre><code class="lang-auto">data = ImageDataBunch.from_name_re(path_img, fnames, pat, ds_tfms=get_transforms(), size=224, bs=bs
                                  ).normalize(imagenet_stats)
</code></pre>
<pre><code class="lang-auto">---------------------------------------------------------------------------
RuntimeError                              Traceback (most recent call last)
~\AppData\Local\Programs\Python\Python38\lib\site-packages\fastai\data_block.py in _check_kwargs(ds, tfms, **kwargs)
    593         x = ds[0]
--&gt; 594         try: x.apply_tfms(tfms, **kwargs)
    595         except Exception as e:

~\AppData\Local\Programs\Python\Python38\lib\site-packages\fastai\vision\image.py in apply_tfms(self, tfms, do_resolve, xtra, size, resize_method, mult, padding_mode, mode, remove_out)
    122                     x = tfm(x, size=_get_crop_target(size,mult=mult), padding_mode=padding_mode)
--&gt; 123             else: x = tfm(x)
    124         return x.refresh()

~\AppData\Local\Programs\Python\Python38\lib\site-packages\fastai\vision\image.py in __call__(self, x, *args, **kwargs)
    523         "Randomly execute our tfm on `x`."
--&gt; 524         return self.tfm(x, *args, **{**self.resolved, **kwargs}) if self.do_run else x
    525 

~\AppData\Local\Programs\Python\Python38\lib\site-packages\fastai\vision\image.py in __call__(self, p, is_random, use_on_y, *args, **kwargs)
    469         "Calc now if `args` passed; else create a transform called prob `p` if `random`."
--&gt; 470         if args: return self.calc(*args, **kwargs)
    471         else: return RandTransform(self, kwargs=kwargs, is_random=is_random, use_on_y=use_on_y, p=p)

~\AppData\Local\Programs\Python\Python38\lib\site-packages\fastai\vision\image.py in calc(self, x, *args, **kwargs)
    474         "Apply to image `x`, wrapping it if necessary."
--&gt; 475         if self._wrap: return getattr(x, self._wrap)(self.func, *args, **kwargs)
    476         else:          return self.func(x, *args, **kwargs)

~\AppData\Local\Programs\Python\Python38\lib\site-packages\fastai\vision\image.py in affine(self, func, *args, **kwargs)
    182         m = tensor(func(*args, **kwargs)).to(self.device)
--&gt; 183         self.affine_mat = self.affine_mat @ m
    184         return self

RuntimeError: Expected object of scalar type Float but got scalar type Double for argument #3 'mat2' in call to _th_addmm_out

During handling of the above exception, another exception occurred:

Exception                                 Traceback (most recent call last)
 in 
----&gt; 1 data = ImageDataBunch.from_name_re(path_img, fnames, pat, ds_tfms=get_transforms(), size=224, bs=bs
      2                                   ).normalize(imagenet_stats)

~\AppData\Local\Programs\Python\Python38\lib\site-packages\fastai\vision\data.py in from_name_re(cls, path, fnames, pat, valid_pct, **kwargs)
    156             assert res,f'Failed to find "{pat}" in "{fn}"'
    157             return res.group(1)
--&gt; 158         return cls.from_name_func(path, fnames, _get_label, valid_pct=valid_pct, **kwargs)
    159 
    160     @staticmethod

~\AppData\Local\Programs\Python\Python38\lib\site-packages\fastai\vision\data.py in from_name_func(cls, path, fnames, label_func, valid_pct, seed, **kwargs)
    145         "Create from list of `fnames` in `path` with `label_func`."
    146         src = ImageList(fnames, path=path).split_by_rand_pct(valid_pct, seed)
--&gt; 147         return cls.create_from_ll(src.label_from_func(label_func), **kwargs)
    148 
    149     @classmethod

~\AppData\Local\Programs\Python\Python38\lib\site-packages\fastai\vision\data.py in create_from_ll(cls, lls, bs, val_bs, ds_tfms, num_workers, dl_tfms, device, test, collate_fn, size, no_check, resize_method, mult, padding_mode, mode, tfm_y)
     94                 mode:str='bilinear', tfm_y:bool=False)-&gt;'ImageDataBunch':
     95         "Create an `ImageDataBunch` from `LabelLists` `lls` with potential `ds_tfms`."
---&gt; 96         lls = lls.transform(tfms=ds_tfms, size=size, resize_method=resize_method, mult=mult, padding_mode=padding_mode,
     97                             mode=mode, tfm_y=tfm_y)
     98         if test is not None: lls.add_test_folder(test)

~\AppData\Local\Programs\Python\Python38\lib\site-packages\fastai\data_block.py in transform(self, tfms, **kwargs)
    503         if not tfms: tfms=(None,None)
    504         assert is_listy(tfms) and len(tfms) == 2, "Please pass a list of two lists of transforms (train and valid)."
--&gt; 505         self.train.transform(tfms[0], **kwargs)
    506         self.valid.transform(tfms[1], **kwargs)
    507         if self.test: self.test.transform(tfms[1], **kwargs)

~\AppData\Local\Programs\Python\Python38\lib\site-packages\fastai\data_block.py in transform(self, tfms, tfm_y, **kwargs)
    722     def transform(self, tfms:TfmList, tfm_y:bool=None, **kwargs):
    723         "Set the `tfms` and `tfm_y` value to be applied to the inputs and targets."
--&gt; 724         _check_kwargs(self.x, tfms, **kwargs)
    725         if tfm_y is None: tfm_y = self.tfm_y
    726         tfms_y = None if tfms is None else list(filter(lambda t: getattr(t, 'use_on_y', True), listify(tfms)))

~\AppData\Local\Programs\Python\Python38\lib\site-packages\fastai\data_block.py in _check_kwargs(ds, tfms, **kwargs)
    594         try: x.apply_tfms(tfms, **kwargs)
    595         except Exception as e:
--&gt; 596             raise Exception(f"It's not possible to apply those transforms to your dataset:\n {e}")
    597 
    598 class LabelList(Dataset):

Exception: It's not possible to apply those transforms to your dataset:
 Expected object of scalar type Float but got scalar type Double for argument #3 'mat2' in call
</code></pre>

username: ptrblck
cooked: <p>It seems as if some data tensors are <code>float64</code> tensors, while the default <code>float32</code> is expected.<br>
What does <code>ImageDataBunch.from_name_re</code> do?<br>
Assuming it’s part of the data loading pipeline, are you able to somehow define the desired data type?</p>

username: Nick_Corona
cooked: <p>I’ll try. I’m new to fastai and pytorch</p>

username: Nick_Corona
cooked: <p>No, I can’t find a way to change the type.</p>

username: Nick_Corona
cooked: <p>The way I fixed that snipped of code is by removing the <code>ds_tfms=get_transforms()</code> argument. However, I don’t consider this resolved as it doesn’t seem there’s any way to change the type expected by this function passed to <code>ds_tfms</code>.</p>

username: ptrblck
cooked: <p>I would recommend to create a new topic in the <a href="https://forums.fast.ai/">fastai forum</a> as there are the experts regarding FastAI. <img src="https://discuss.pytorch.org/images/emoji/apple/wink.png?v=9" title=":wink:" class="emoji" alt=":wink:"><br>
I’m unfortunately not familiar enough with the implementation of the lib.</p>

username: Nick_Corona
cooked: <p>Lol, I actually thought I was posting on the fastai forums because they look so similar. Thanks.</p>