Introduction to Python¶

Python is a general purpose programming language. While we are using Python to build program using big data streams it can be used for many types of applications and is highly popular in web-based applications. Python was originally developed by Guido van Rossum in the Netherlands in the late 1980s and is now in its third major version.

Just as NetLogo and Blockly provided an environment for executing programs written in their languages we will need to use a similar execution environment for our Python programs. We will see how to use a particular system for editing and executing Python programs.

Python is a textual language. Similar to NetLogo, a program written in Python is simply lines of text. The text, of course, must follow the rules of syntax for the Python language just like written English prose must follow the rule of syntax for the English language. We will see the syntax for Python statements and also see what happens if the syntax is not followed correctly.

A new element of programming - what Python terms modules - will also be introduced. A modules is a collections of reusable components intended to be used in the construction of new programs. modules help programmers avoid “reinventing the wheel” with each new program. The community of programmers using Python has created a large number of modules that provide powerful facilities for audio, databases, game development, geographic information systems, image handling, and visualization. The functions for accessing the big data streams are packaged as a module. We will see soon how the big data module is used. Later we will look at how to use some of the visualization libraries.

Our study of Python is guided by two ideas. First, in the previous chapters we have built up a good knowledge base about computation and programming. The basic notions of abstraction and algorithms (calculation, sequence, decision, and iteration) are familiar building blocks. We have already seen these algorithmic and program building blocks in Blockly.  You may also have looked ahead at Python by looking at the Python code generated in Blockly. Also, the idea of using a function will be seen in the context of creating visualizations.Second, we are focused on using Python for big data applications. Some elements of the Python language are essential to working with big data. These language elements will be at the center of our attention.

This study of Python will build on what you already know with minimal repetition and focus on the essential Python elements needed for big data programming. This presentation is not intended as a “beginner’s guide” to Python because you are not beginners. In pursing this course, many details of the language are either ignored or given very light treatment. There are good references to be found on-line to “fill in the gaps” in our presentation of Python. Because programming languages are always evolving (this is, after all, the third version of Python) it is a valuable skill to be able to find out details of a programming language on your own.