Update README.md to include pyqt in conda install

[psobolewskiPhD]

the napari package on conda-forge no longer includes a QT backend, see:
napari/docs#202
conda-forge/napari-feedstock#48

So the stand-alone conda instructions need to include one, e.g. pyqt.
Here's the napari.org instructions:

screenshot from: https://napari.org/stable/tutorials/fundamentals/installation.html#install-as-python-package-recommended

[haesleinhuepf]

Awesome, thanks @psobolewskiPhD !

[thawn]

when I try mamba install pyqt I get the following error (on a M1 mac):

Encountered problems while solving:
  - package harfbuzz-7.3.0-h46e5fef_0 requires icu >=72.1,<73.0a0, but none of the providers can be installed

[psobolewskiPhD]

Is this into an existing env? I don't have that package in any of mine...
Can you try:
mamba repoquery whoneeds harfbuzz

Also you can try pyside2 instead of pyqt...

[thawn]

@psobolewskiPhD thanks for looking into this 😄

Is this into an existing env?

no, it is a fresh env that I created just now for testing. My older devbio-napari environments do not have that issue either.

Can you try: mamba repoquery whoneeds harfbuzz

This returns:
libass 0.17.1 h4da34ad_0 harfbuzz >=7.2.0,<8.0a0 conda-forge

Also you can try pyside2 instead of pyqt...

mamba install pyside2 returns this error:

Encountered problems while solving:
  - package pyside2-5.15.5-py39h46bc059_1 requires qt-main >=5.15.4,<5.16.0a0, but none of the providers can be installed

[psobolewskiPhD]

Hmm, I can't reproduce on my M1 using instructions from the README.
mamba create --name devbio-napari-env python=3.9 devbio-napari pyqt -c conda-forge -c pytorch
Can you give me a snippet of how you're making the environment?

[thawn]

@psobolewskiPhD I can confirm, that the official install command fixed it for me

I had used the old install command from this blog post:

mamba create -n my_first_env devbio-napari python=3.9 -c conda-forge

I will create a pull request for that blog post shortly.

Btw, why is there -c pytorch in the install command? I did not see any package that was installed from that channel on my system.

Also, I suggest to put pyqt in the dependency list of devbio-napari - rather than in the installation instructions. Because it seems like it is not possible to fix a missing pyqt after installation (at least it was not possible for me).

[psobolewskiPhD]

If I recall PyTorch was needed for windows install?

Also, I suggest to put pyqt in the dependency list of devbio-napari - rather than in the installation instructions. Because it seems like it is not possible to fix a missing pyqt after installation (at least it was not possible for me).

This would actually be bad, because devbio-napari is technically an installable plugin.
See also: https://napari.org/stable/plugins/best_practices.html#don-t-include-pyside2-or-pyqt5-in-your-plugin-s-dependencies
So a user could try to install it into their existing napari ecosystem, which might use PyQT6 (like mine) or Pyside2 QT backends. Then, devbio-napari would install a second Qt backend, which would probably break the env.
Also, pyqt doesn't have arm64 wheels so someone using the build in plugin manager would get errors.

BTW: modifying your instructions also works for me:
mamba create -n my_first_env -c conda-forge python=3.9 devbio-napari pyqt
but indeed installing pyqt into an existing env fails as you described. I'm not sure why to be honest.