Pip

Python install

Follow this guide.

Attention: Always use python3 (or python3.9) command. python command will point to OSX system python 2.7!

VSCode workflow

So far graphics do not show when running virtual env versions

IPython interactive console

• Add #%% to add cells which can be run individually.
• Press Shift + Enter to run line or selection in iPython console.

Jupyter output pane

• Select code and press Option + Enter to run selection in Jupyter Output pane

Commands

• Strg + Enter: Execute cell

Tooling/packages

ipython

Run ipython to open the interactive shell.

• !ls runs ls in the standard shell
• ?name or name? shows infos about that piece of code.

venv

NOTE: Use venv (NOT virtualenv) on OSX - the later has issues on OSX!

1. In the project directory type python3 -m venv ./env (or python3 -m venv venv)
2. Activate the virtual environment using source env/bin/activate (or source venv/bin/activate)
3. Install dependencies as usual with pip install (or pip install -r requirements.txt). Use pip list to see the dependencies installed in the current folder.
4. Type deactivate to deactivate the current virtual environment.

virtualenv

Convention: Call virtualenv folder env.

1. Setup: virtualenv env
2. Activate virtualenv: source env/bin/activate
3. Install packages (e.g. requests package) with pip of virtualenv: env/bin/pip install requests (running pip install should automatically call env/bin/pip install )
4. Find the installed packages of the environment at env/lib/python3.7/.
5. To exit virtual env: deactivate

pip

Install from existing requirements.txt

Install all files listed in a requirements.txt file:

pip install -r requirements.txt

Example of requirements.txt:

requests
APScheduler
flask
flask-cors
flask-restplus
numpy
pandas
python-dotenv
Shapely
ipython
scikit-learn
SQLAlchemy
psycopg2
pyproj
boto3
requests-aws4auth
tables
tensorflow
keras

Create own requirements.txt

Run

pip freeze > requirements.txt

to create a requirements.txt file from the currently installed packages.

upgrade pip packages

Use the tool https://github.com/achillesrasquinha/pipupgrade

pipupgrade --interactive

pip3 (like npm install --save-dev)

pip3 install package && pip3 freeze > requirements.txt

HOW TO install new python packages on my OSX system

I’ve got homebrew and pip. The latter is a program to manage python packages

The commands are basically:

pip install <package_name>

Pip syntax

List of all packages available with pip

Work on prod. environment

Python Developers Survey 2018 Results

Options:

• miniconda + pip
• pip freeze
• pip + virtualenv
• docker + pip (with auto-generated requirements file from pycharm)

Pycharm

Use evaluate window to quickly run things (like matlab)

Poetry

• poetry is an alternative package manager for python

Create project

1. poetry new

   poetry new my-project

2. poetry init

   1. Create folder and navigate to it
   2. Run poetry init <— Running the init command will take you into an interactive session to define the parameters of your new project. Just hit enter on each question - this will use the defaults (in the []).

   See this tutorial to start poetry with django.

Add dependencies

poetry add name-of-dependency

Environment

• Run poetry shell to start a virtual environment. Type exit to exit.