install python 3 and the conda package management if you don’t already have it.

• do which python and python --version to see if you already have python installed, and if so, what version you have. Versions 3.x are not back-compatible with version 2.x. We will work with version 3. If you see that you have version 2.x (like 2.7.16), then you will need to install python 3.

• it’s easy to have python installed in many different places on the same machine (without knowing it). say one python installed with homebrew, one installed with conda, one installed with pip. and it’s okay (but best to know it). So if you already have python 2.x on your laptop and follow the instructions below to get python 3.x with anaconda, you will have both versions: it’s okay. You will learn how to know which version you use by default, and how to switch.

• follow instructions from software carpentry, with anaconda.
  • make sure to choose python 3.x and not Python 2.7.
  • read below on miniconda if you want a lighter installation that uses less memory
  • if you have a Windows machine using Linux with WSL, then do not use the software carpentry instructions: you need to install python in a place that your Linux subsystem can use. Python comes with Ubuntu, which you probably chose as your Linux distribution when you installed WSL: try which python and which python3. To install python packages, you could
    • install conda, then do conda install x to install package x
    • or install pip then do pip install x to install package x.

• test that the installation worked, by checking which version you have, and checking that you can import the numpy package, for instance:

  $ conda --version
  conda 4.8.3
  $ conda list | grep numpy  
  numpy                     1.18.5           py38h1da2735_0  
  numpy-base                1.18.5           py38h3304bdc_0  
  numpydoc                  1.1.0                      py_0
  $ which python
  /Users/ane/opt/anaconda3/bin/python
  $ python --version
  Python 3.8.3
  $ python
  >>> import numpy
  >>> quit() # or just control-D
  

  If you don’t get anything or not a python 3.x version, exit your shell, open it again, and try python --version again. Also do conda list to see what conda installed for you.

• to update, later: conda update conda to update the package manager, then conda update python to update python, then conda update anaconda to update packages that are shipped with anaconda.

miniconda

• Anaconda installs for you several things: the conda package manager, python, ipython notebook, and many python libraries like numpy and scipy. (minimum 3 GB disk space required). If you want a lighter installation, install miniconda3 instead. Then test that your installation worked (see above).

• Miniconda gets you python 3 and the conda package manager. With conda you can install any other packages later, as you need them.

• Please install the numpy library with: conda install numpy.

• The jypyterlab package can be installed from the conda-forge channel with: conda install -c conda-forge jupyterlab.

• To learn how to work with conda and manage different versions of Python (if you come to need Python 2, for instance), read about conda environments in the conda doc.

next: intro to python