# Problems with alpaca 

**URL:** <https://discourse.slicer.org/t/problems-with-alpaca/43461>\
**Category:** Support\
**Tags:** alpaca\
**Created:** [June 23, 2025, 5:13pm UTC](https://discourse.slicer.org/t/problems-with-alpaca/43461 "2025-06-23T17:13:36Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![aventador17](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/aventador17/32/80490_2.png) [@aventador17](https://discourse.slicer.org/u/aventador17)\
**Post date:** [June 23, 2025, 5:13pm UTC](https://discourse.slicer.org/t/problems-with-alpaca/43461/1 "2025-06-23T17:13:36Z")

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Hello, this is my first time using 3d slicer. I write to community 'cause I have had some problem with ALPACA, it does not run . The phyton console showes this:

In the future `np.bool` will be defined as the corresponding NumPy scalar.  
Traceback (most recent call last):  
File “C:/Users/USUARIO/AppData/Local/slicer.org/Slicer 5.8.1/slicer.org/Extensions-33241/SlicerMorph/lib/Slicer-5.8/qt-scripted-modules/ALPACA.py”, line 105, in setup  
from itk import Fpfh  
File “C:\Users\USUARIO\AppData\Local\slicer.org\Slicer 5.8.1\lib\Python\Lib\site-packages\itk\__init_\_.py”, line 59, in   
from itk.support.extras import \*  
File “C:\Users\USUARIO\AppData\Local\slicer.org\Slicer 5.8.1\lib\Python\Lib\site-packages\itk\support\extras.py”, line 37, in   
import itk.support.types as itkt  
File “C:\Users\USUARIO\AppData\Local\slicer.org\Slicer 5.8.1\lib\Python\Lib\site-packages\itk\support\types.py”, line 178, in   
) = itkCType.initialize\_c\_types\_once()  
File “C:\Users\USUARIO\AppData\Local\slicer.org\Slicer 5.8.1\lib\Python\Lib\site-packages\itk\support\types.py”, line 143, in initialize\_c\_types\_once  
_B: “itkCType” = itkCType(“bool”, “B”, np.dtype(np.bool))  
File "C:\Users\USUARIO\AppData\Local\slicer.org\Slicer 5.8.1\lib\Python\Lib\site-packages\numpy\_init_.py", line 353, in **getattr**  
raise AttributeError( **former\_attrs** [attr])  
AttributeError: module ‘numpy’ has no attribute ‘bool’.  
`np.bool` was a deprecated alias for the builtin `bool`. To avoid this error in existing code, use `bool` by itself. Doing this will not modify any behavior and is safe. If you specifically wanted the numpy scalar type, use `np.bool_` here.  
The aliases was originally deprecated in NumPy 1.20; for more details and guidance see the original release note at:  
[NumPy 1.20.0 Release Notes — NumPy v2.4.dev0 Manual](https://numpy.org/devdocs/release/1.20.0-notes.html#deprecations)

I hope someone could help me, I would be very grateful

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**Author:** ![muratmaga](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/muratmaga/32/3622_2.png) [@muratmaga](https://discourse.slicer.org/u/muratmaga)\
**Post date:** [June 23, 2025, 5:15pm UTC](https://discourse.slicer.org/t/problems-with-alpaca/43461/2 "2025-06-23T17:15:27Z")

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please see the workaround in this thread:

> [@Opening ALPACA for the first time and stuck on "Installing ALPACA Python Packages...."](https://discourse.slicer.org/t/opening-alpaca-for-the-first-time-and-stuck-on-installing-alpaca-python-packages/43415/3):
>
> @jsguerra If you are tracking the github issue, until the fix is integrated, the workaround is to manually install the numpy. These steps worked for me: in Python console type `pip\_install(“numpy==2.00”)’ Restart Slicer Switch to ALPACA It should continue installing remaining packages (pandas) and then ALPACA should be working.

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**Author:** ![aventador17](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/aventador17/32/80490_2.png) [@aventador17](https://discourse.slicer.org/u/aventador17)\
**Post date:** [June 24, 2025, 2:09am UTC](https://discourse.slicer.org/t/problems-with-alpaca/43461/3 "2025-06-24T02:09:51Z")

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Thenks a lot for your answer. I have installed numpy as you said, but a new error has appeared, it says: “AttributeError: `np.Inf` was removed in the NumPy 2.0 release. Use `np.inf` instead.”

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**Author:** ![jamesobutler](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/jamesobutler/32/7511_2.png) [@jamesobutler](https://discourse.slicer.org/u/jamesobutler)\
**Post date:** [June 24, 2025, 8:26am UTC](https://discourse.slicer.org/t/problems-with-alpaca/43461/4 "2025-06-24T08:26:54Z")

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FYI @smrolfe

> <https://github.com/SlicerMorph/SlicerMorph/blob/4b3234c5cd36e235cdd906835faa202626d3f413/ALPACA/ALPACA.py#L2500>

I would suggest adding the ruff hook to SlicerMorph’s pre-commit-config like in Slicer as ruff includes a numpy 2 deprecation rule that can auto apply fixes ( [numpy2-deprecation (NPY201) | Ruff](https://docs.astral.sh/ruff/rules/numpy2-deprecation/)).

> <https://github.com/Slicer/Slicer/blob/406beac7a2583eed3cc91513f7aaa314d6668cc9/.pre-commit-config.yaml#L20>

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**Author:** ![muratmaga](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/muratmaga/32/3622_2.png) [@muratmaga](https://discourse.slicer.org/u/muratmaga)\
**Post date:** [June 24, 2025, 4:57pm UTC](https://discourse.slicer.org/t/problems-with-alpaca/43461/5 "2025-06-24T16:57:07Z")

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Thanks @jamesobutler

When is Slicer going to officially transition to numpy 2?

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**Author:** ![jamesobutler](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/jamesobutler/32/7511_2.png) [@jamesobutler](https://discourse.slicer.org/u/jamesobutler)\
**Post date:** [June 24, 2025, 6:04pm UTC](https://discourse.slicer.org/t/problems-with-alpaca/43461/6 "2025-06-24T18:04:44Z")

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Slicer preview already comes with numpy 2 bundled. This was updated as part of the transition to Python 3.12. Most latest Python packages have numpy binary compatibility with numpy 1 and 2.

> <https://github.com/Slicer/Slicer/blob/6afc5bc94decd35561717583fde1c3f63d6fb5d8/SuperBuild/External_python-numpy.cmake#L43>

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**Author:** ![aventador17](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/aventador17/32/80490_2.png) [@aventador17](https://discourse.slicer.org/u/aventador17)\
**Post date:** [June 25, 2025, 1:35am UTC](https://discourse.slicer.org/t/problems-with-alpaca/43461/7 "2025-06-25T01:35:49Z")

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Muchas gracias por tu repsuesta, el problema fue solucionado. Ten un maravilloso día. 🙌