No module named 'mmcv._ext'

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State:
Created 3 years ago
Comments:10 (2 by maintainers)

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11reactions

yuzhjcommented, Sep 15, 2020

you can have a try pip uninstall mmcv pip install mmcv-full

0reactions

ejduwellcommented, May 4, 2022

For anyone still having trouble with the "no module named ‘mmcv.ext’ above: I had this issue as well working in OSX on a new m1 macbook. I was able to solve the issue by building mmcv from source. There are detailed directions on how to do so here:

https://mmcv.readthedocs.io/en/latest/get_started/build.html

However, I’ve also pasted the steps below:

git clone https://github.com/open-mmlab/mmcv.git cd mmcv

pip install -r requirements/optional.txt

!“If you are on macOS, add the following environment variables before the installing command.”!: CC=clang CXX=clang++ CFLAGS=‘-stdlib=libc++’ MMCV_WITH_OPS=1 pip install -e .

I complied/installed mmcv in my /opt/anaconda3/lib/python3.9/site-packages/ directory along with mmocr. That way they are both automatically on my path in my anaconda/python environments.

Hope this helps, Ethan

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