Food webs notebook

DSTA

Data Science and Complex Networks

Basic concepts

Outline

  • notebooks are an advanced mechanism for software distribution and integration

  • they execute inside the default container of web browsers

  • we are isolated from the python implementation (away from the actual execution)

  • The Jupyther .ipynb format is standard

  • Markdown cells are used for comments and explanations

  • to run the cells, J. requires a callable Python kernel

  • a notbook is a JSON file, with JavaScript execution

  "cell_type" : "code",
  "execution_count": 1, # integer or null
  "metadata" : {
      "collapsed" : True, # whether the output of the cell is collapsed
      "autoscroll": False, # any of true, false or "auto"
  },
  "source" : ["your code goes here"],
  "outputs": [{
      # list of output dicts (described below)
      "output_type": "stream",
      ...
  }],
  }

Jupiter Notebooks

Detailed installation instructions are at the Jupyter project website

Installation is similar to a Python module but it runs stand-alone and interacts via browser

It requires a Python ‘core’ to run in the background, similar to VS Code (but less coding support)

Online Jupyter Notebooks

All notebooks are also available online on Google Colab

A Google account is required

Jupyter to learn Network analysis

  • start the Jupyter Notebook server, e.g.,
pip install jupyter

jupyter notebook

Python 3 notebooks are available from this module repo

Original Python 2 notebooks are available at the textbook repo

Jupyter to learn Network analysis, II

Currently VS Code supports Jupyter with a dedicated extension

Also, a cell block in a plain Python files can be split up into cells that can be run separately, Jupyuter-style.

Use # %% at the beginning of a line to delimit cells; the cell buttons will appear.

Conventional top-to-bottom execution is preserved.

Plan for the lab

  • study the “Food web” notebook associated to Chapter 1 of Caldarelli-Chessa’s textbook.

  • append your code in the cell below the Q questions.

  • test ‘what if’ questions by changing the code cells: double-click on the cell opens it up for editing.

  • a solution is available, but please read it only after you have tried to solve the problem.

  • We will repeat the experience next week with C-C’s Trade Networks notebook.