Setup for Python.
I've added a Makefile so you can have a look at what commands do what without having to do much.
To run each example in the make file just execute
make <name of task>
e.g.
make piplist
To runn python you need a python runtime. This is a basically an interpreter for the python language that translates you code into a actual operations. You don't really need to know anything about this. But what is inportant is understanding that there are many different ways to setup python on your machine.
find out what version of python you have with
python --version
you can also find out some information about where python runtime is located with
which python
This will help you identify which python you are currently using.
you'll find that mac comes with a pre-shipped version of python. Generally this gets in the way and its best to ignore it.
pyenv is a good way but a little restrictive and hasn;t really developed into industry standard. It has a few problems with how it sets up virtual enviroments. IT acutally uses the base system python as a python runtime and then builds virtual envs ontop of them (not the best)
can write more here ont his if you want but I don't think you need it
# install
brew install pyenv
# add config to zsh (If you don't use zsh , get it and do)
echo '
export PYENV_ROOT="$HOME/.pyenv"
export PATH="$PYENV_ROOT/bin:$PATH"
if command -v pyenv 1>/dev/null 2>&1; then
eval "$(pyenv init -)"
fi
' >> ~/.zshrc
# install zlib
brew update
brew upgrade
brew install zlib
export CFLAGS="-I$(brew --prefix openssl)/include -I$(xcrun --show-sdk-path)/usr/include"
export LDFLAGS="-L$(brew --prefix openssl)/lib"
# set python 3.6.8 as default
pyenv install 3.6.8
pyenv global 3.6.8
# update config in current terminal
exec $SHELL
# this should display v3.6.8
python --version
This is a product built by continium and is kinda cool. It has some problems with it aswell and can be quite large if you go fro the full anacaconda instalation.
- Anaconda: The full python runtime + loads of pre built ananconda specific versions of python libs. It also comes with alot of stuff you dont need and can be an issue when you want portability and sharable/ recreatable environments
- miniconda: you can basically get the basic python runtime with this and only use that (This is my recommendation. I like and use this solution).
Get the conda setup here
https://repo.anaconda.com/miniconda/Miniconda3-latest-MacOSX-x86_64.sh
run the installer
bash Miniconda3-latest-MacOSX-x86_64.sh -b -p $HOME/miniconda
conda init
you can create new python installtions with the following (say this will create python 3.6 runtime)
conda create -n python3.6 python=3.6 -c conda-forge
conda install -n python3.6 virtualenv
python --version
When developing its good to isolate the environment you are working on from the underlying system its running on. one simple ( but not entirely robust) way of doing this is using virtua environments. Think of these are little isolated sandboxes that think they are all that exists. The start as blank slates. You install libs into them. You can destroy them / recreate them. Just get used to them.
To create a virtual env you can use the venv module in the base python, and define the directory in which to create this venv,
python -m venv .my-virtual-env
This will create a hidden directory called .my-virtual-env in the current directory.
You can activate this venv here by sourcing the activate file
. ./.my-virtual-env/bin/activate
once activated using python and pip will use those related to the virtual env.
You can also just use the python binary or related pip binary in this environment with
./.my-virtual-env/bin/python
or
./.my-virtual-env/bin/pip
Make sure you are not in an activated virtual environment by executing deactivate and checkout what happens if you execute
./.my-virtual-env/bin/pip list
versus
pip list
You should see the difference in the libraries installed in virtual env verses those installed in the global python runtime environment.