Unable to find installation candidates for httpstan

[scholarazwa]

Hi. I am trying to install pystan via poetry and it always get stuck at installing httpstan, no matter what the version is.

Here what I did: poetry add pystan="3.5.0" -> Installing httpstan (4.8.2): Failed poetry add pystan="3.6.0" -> Installing httpstan (4.9.1): Failed poetry add pystan="3.7.0" -> Installing httpstan (4.10.1): Failed

The error says "Unable to find installation candidates for httpstan (4.x.x)"

Can someone help me on how to resolve this? Thank you.

Btw, I am on an M2 Apple Silicon Macbook Air.

[riddell-stan]

Thanks to the work of @mikediessner we now have an FAQ item for this: https://pystan.readthedocs.io/en/latest/faq.html#how-can-i-run-pystan-on-macos-with-apple-silicon-chips-apple-m1-m2-etc

[scholarazwa]

Thanks. Let me try that and report back.

[scholarazwa]

I have tried the suggested solution and it works. Just a few notes for others in the future:

• If you already have poetry installed you can skip the 'python3 -m pip install poetry' and 'python3 -m poetry build' step.
• Instead, just do 'poetry init' to initialize the httpstan folder with poetry.
• Then, simply run 'poetry build'.
• The output will be two files: a '.tar.gz' and a '.whl' in the dist folder.

Next, to install httpstan into an existing project, just copy the output files above into your project folder , then do:

• pip install *.whl
• After that, install pystan via 'pip install pystan --no-binary pystan'
• Now you have both httpstan and pystan installed.

In my case, I needed the above packages in order to make Prophet work. So now I can simply do:

• 'poetry add prophet'
• And my environment is now setup correctly.