How to install numpy for Python 2 with choco?

Question

I want to use chocolately to install numpy onto a Windows machine.

However when I run:

choco install numpy

it tried to install a numpy for Python 3.

How can I force it to install a version for Python 2?

Answer 1

How do I install numpy for Python 2 with choco?

Run choco install numpy.

When I ran choco install numpy, it tried to install numpy for Python 3. How can I force it to install a version for Python 2?

The trick here is that if you look at the chocolateyinstall.ps1 and chocolateyuninstall.ps1 files for the Chocolatey numpy package you've linked to (under Files), the package itself simply uses the version of Python installed on your system, along with Python's pip package manager, to install and uninstall Python packages.

Therefore, the simplest way to handle this is to:

• Add Python 2.7 (e.g. C:/path/to/Python27) your Windows path variable(s) and remove/rename any entry for e.g. Python 3.7.

• Log off and then back on to reload your path variable(s). Open a command prompt and check that python -V returns e.g. Python 2.7.16.

• Run choco install numpy. Say no to installing e.g. Python 3.7 and yes to installing numpy. As long as there is an entry in green that says numpy was installed successfully, you can likely ignore any other messages/errors.

To verify that numpy was installed successfully, run python from a command window and enter import numpy at the interactive >>> prompt. If there is no error message, numpy has been imported successfully.

Caveats

This method obviously relies on Python 2.7 being the default python on your system. If this changes, you may run into issues in the future.

Notes

Alternatively, since Chocolatey is simply using pip in the background, you can use e.g. C:/path/to/Python27/python.exe -m pip install numpy to install numpy directly (minus an entry in Chocolatey).