I want to use pyROOT in a virtualenv, I have ROOT installed on my system, when outside the virtualenv I can do import ROOT and it works, but inside a virtualenv doing an import ROOT gives the following error:
ModuleNotFoundError: No module named 'ROOT'
How do I add ROOT in there?
Thanks in advance.
You'll need to install root within the virtual environment too. Run a pip install command after activating the environment.
Like many Python packages, support for the ROOT framework in Python exists as two parts...a C++ framework, and a Python binding around that framework. In this case, both the C++ framework and the Python binding are provided by the same group and so are discussed together on the same web site. https://root.cern is the home page for the framework, and https://root.cern/manual/python is the Python module page.
The C++ framework should be installed first. How that is done will vary by platform. Then, the Python module should be installed into each Python version and/or virtual environment in which one wishes to use the ROOT framework, via the command:
pip install pyroot
Say you have a virtualenv in the directory ~/envs/myenv. You'd then want to do:
source ~/envs/myenv/bin/activate
pip install pyroot