Specific reasons to favor pip vs. conda when installing Python packages

Question

I use miniconda as my default python installation. What is the current (2019) wisdom regarding when to install something with conda vs. pip?

My usual behavior is to

Answer 1

As add-on to @eatmeimadanisch and @merve's recommendation "use conda first, thenn try pip", here is the corresponding code to run this from the command line of a linux system:

while read requirement; do conda install --yes $requirement || pip install $requirement; done < requirements.txt

This assumes that all packages with desired package number are put into a file called "requirements.txt". The entries look like this for example:

matplotlib==2.0.0
numpy==1.18.1

Note that the equal sign is double (==), not single (=).