Vespa Installation Issues for PyGamma

Hi community,
Thank you for providing a space to ask questions and receive advice - it’s greatly appreciated. I’m attempting to install Vespa on my Windows 10 laptop by following the directions on New Vespa Installation · Vespa Documentation. However, I’m running into an issue installing the pygamma library at Step 3 of the provided link. More specifically, the error prompt reads:
ERROR: Could not find a version that satisfies the requirement pygamma (from versions: none)
ERROR: No matching distribution found for pygamma

I was able to install the vespa-suite module, but I can’t seem to figure out why pygamma won’t install. According to the PyGamma documentation (New Install or Upgrade · PyGAMMA/GAMMA Docs), it should work with Python 3.7. All the other required modules have been installed successfully, so what am I missing?

Thank you for your time,

Hi Warren,

Welcome to the forum - glad you found us! Let me tag @bsoher who should be able to help you directly.


Hi Warren,

Sorry for the delay, but it’s grant writing season (it’s always grant writing season … :frowning:).

So, I ran my Win10 VM and tested installing pygamma from PyPI using pip into a python 3.7 environment in conda … just like the Vespa docs state. And it just works for me. See screen shot below.

So, the basic mechanism isn’t broken, I think. So let’s troubleshoot at your end. Silly question, but are you running 64 bit Python? And I checked PyPI and there are still pygamma wheels for v4.3.4 for python versions 3.7, 3.8 and 3.9 available. Though, I’ve not checked the Vespa software thoroughly for any python other than python 3.7. Which is why I recommend installing Vespa/pygamma in python 3.7

Anyway, I digress. Can you check those things for me. Then run the install again for pygamma and take a screenshot and post it here if it does not work. Thanks,


What a simple mistake on my end! I’m working on a Windows Surface Pro which uses an ARM-based processor; evidently, only 32 bit Python is compatible as a result. Sorry about the confusion.

As a side note, is it possible to run Vespa on Python 3.6.8? I know that you mentioned Vespa/pygamma would work best in Python 3.7, however, that’s the current version of Python installed on the lab’s principal computer.