# AttributeError: 'builtin\_function\_or\_method' object has no attribute 'fftn'

**URL:** <https://discuss.pytorch.org/t/attributeerror-builtin-function-or-method-object-has-no-attribute-fftn/109744>\
**Category:** complex\
**Created:** [January 23, 2021, 3:03am UTC](https://discuss.pytorch.org/t/attributeerror-builtin-function-or-method-object-has-no-attribute-fftn/109744 "2021-01-23T03:03:34Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![kiranchari](https://discuss.pytorch.org/user_avatar/discuss.pytorch.org/kiranchari/32/33753_2.png) [@kiranchari](https://discuss.pytorch.org/u/kiranchari)\
**Post date:** [January 23, 2021, 3:03am UTC](https://discuss.pytorch.org/t/attributeerror-builtin-function-or-method-object-has-no-attribute-fftn/109744/1 "2021-01-23T03:03:34Z")

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Hi, I am using torch version ‘1.7.1+cu110’ but fftn appears to be missing at torch.fft.fftn.

According to [torch.fft — PyTorch 1.7.0 documentation](https://pytorch.org/docs/1.7.1/fft.html#torch.fft.fftn) this should exist.

Any advice? Thanks

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<div class="post-metadata">

**Author:** ![ptrblck](https://discuss.pytorch.org/user_avatar/discuss.pytorch.org/ptrblck/32/1823_2.png) [@ptrblck](https://discuss.pytorch.org/u/ptrblck)\
**Post date:** [January 23, 2021, 7:32am UTC](https://discuss.pytorch.org/t/attributeerror-builtin-function-or-method-object-has-no-attribute-fftn/109744/2 "2021-01-23T07:32:08Z")

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I guess you might be missing the `import torch.fft` statement and thus `torch.fft.fftn` will raise an error.

```python
>>> import torch
tor>>> torch. __version__'1.7.1'
>>> torch.fft.fftn
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'builtin_function_or_method' object has no attribute 'fftn'

>>> import torch.fft
>>> torch.fft.fftn
<built-in function fft_fftn>

```

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<div class="post-metadata">

**Author:** ![kiranchari](https://discuss.pytorch.org/user_avatar/discuss.pytorch.org/kiranchari/32/33753_2.png) [@kiranchari](https://discuss.pytorch.org/u/kiranchari)\
**Post date:** [January 24, 2021, 2:36am UTC](https://discuss.pytorch.org/t/attributeerror-builtin-function-or-method-object-has-no-attribute-fftn/109744/3 "2021-01-24T02:36:08Z")

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Thanks @ptrblck, that fixed it. I didn’t see this line in the docs:

> “To use these functions the torch.fft module must be imported since its name conflicts with the [`torch.fft()`](https://pytorch.org/docs/stable/generated/torch.fft.html#torch.fft) function”