Programming with Python

Understanding what Python is and what it can be used for

What is programming?

A way to instruct a computer to perform tasks.

There are numerous programming languages, the choice of which can depend upon:

• Availability within the given context

• Suitability for performing a particular task

• Knowledge of the programmer and other users

What is Python?

A high-level, popular, general-purpose programming language.

• High-level: closer to human languages than machine code; very readable and relatively simple syntax

• Popular: expected to become the most popular programming language (and already is by some metrics)

• General-purpose: can be used for a wide variety of applications, such as games, web apps, and data analysis

Python for Data Analysis

• Numerous open-source packages created and maintained by an active and growing Python community, to simplify programming for:

  • Data processing, analysis and visualisation

  • Data collection via APIs and web scraping

  • Machine learning and predictive modelling

Python for Data Analysis

• Ability to handle larger volumes of data in a more robust, repeatable manner and with greater control than traditional spreadsheet applications such as Excel

  • Repeated operations are carried out more efficiently

  • Program logic is not hidden within the user interface

Where Python can be written and executed

• via the command-line interface

  • Command Prompt on Windows or Terminal on Mac / Linux

  • text-based with limited formatting of outputs

• via an IDE (Integrated Development Environment)

  • typically with features such as syntax highlighting and debugging tools

• via an interactive notebook interface

  • typically with features such formatted display of code output and the ability to combine code with other media such as text and images

Jupyter notebook

A web-based, interactive computing notebook interface:

• Create documents containing live code, visualisations and narrative text

• Embed HTML, images and videos and use interactive widgets

• Support for numerous programming languages (originally Julia, Python and R)

Notebook components

• A kernel is a program which runs the code cells in a notebook

  • such as our installation of Python

• A notebook is made of different types of cells:

  • Markdown cells can be used to add headings, notes and text lists

  • Code cells contain code compatible with the selected kernel

• Additional functionality and numerous extensions available, such as:

  • Slideshow creation

  • Code formatting tools