# Installing with mac and virtual environments

**URL:** <https://discourse.numenta.org/t/installing-with-mac-and-virtual-environments/7666>\
**Category:** Engineering\
**Tags:** question\
**Created:** [June 16, 2020, 2:16pm UTC](https://discourse.numenta.org/t/installing-with-mac-and-virtual-environments/7666 "2020-06-16T14:16:36Z")\
**Posts on this page:** 1\
**Showing post:** 4

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**Author:** ![mcleverley](https://avatars.discourse-cdn.com/v4/letter/m/5f9b8f/32.png) [@mcleverley](https://discourse.numenta.org/u/mcleverley)\
**Post date:** [June 16, 2020, 3:45pm UTC](https://discourse.numenta.org/t/installing-with-mac-and-virtual-environments/7666/4 "2020-06-16T15:45:51Z")

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Thanks for the info. I installed htm.core with PyPi before posting, but on loading hotgym.py example from the github I get some errors on predictor.infer().

> —\> 30 pdf = predictor.infer( tm.getActiveCells() )  
> 31 for n in (1, 5):  
> 32 if pdf[n]:
> 
> RuntimeError: CHECK FAILED: “dimensions\_ != 0” Classifier:  
> must call `learn` before `infer`.

Running the hotgym.py file itself in a cloned repo gives me ‘no module named numpy found’ even though I’ve installed numpy normally on my system; I’ll look into a source build rather than PyPi.  
Perhaps I’m just missing something fundamental in the code structure; I’ll read up a bit more on how to get htm.core to work.

It looks like I should be able to follow the nupic [API documentation](http://nupic.docs.numenta.org/stable/api/index.html) while referencing the htm.core [API differences](https://github.com/htm-community/htm.core/blob/master/API_DIFFERENCES.md) for syntax.

 ![Screen Shot 2020-06-16 at 11.48.21 AM](https://canada1.discourse-cdn.com/flex030/uploads/numenta/original/2X/c/c9200615748d8f98cf7d477ec389cd68ee9a8d9b.png)

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