Python Scripting Language W04IST-SI4011

Course Introduction

• Course title: Script Languages (W04IST-SI4011)
• Faculty: Faculty of Information and Communication Technology
• Department: Department of Applied Informatics
• Teachers: Wojciech Thomas, PhD
• Course completion conditions: Get passing grades from lab exercises, pass the final exam, and follow the cheating and plagiarism policy

Lecture and Lab Completion

• Lecture activities: Ad hoc, random, and no negative points
• Lab completion conditions: Presence is obligatory, create a user account in Safari Books Online, follow the cheating and plagiarism policy, and demonstrate ability to explain code and write clean code

Python Resources

• Python DOCS: https://www.python.org/doc/
• Recommended books: Learning Python, Impractical Python Projects, and Automate the Boring Stuff with Python
• Python flavors: Python, IPython, Jupyter Notebook, and Anaconda

Python Environment

• Python is a "batteries included" environment with a distribution made by Python developers
• Dependency management with pip: pip install, pip install --upgrade, and python -m pip install --upgrade pip
• IPython adds extra functions to Python shell, including syntax highlighting, help, variables introspection, magic commands, and TAB completion

Python Code File

• Python files use .py extension
• On Windows, .py extension suggests a tool to run the code
• On Linux/iOS, you need to add a "shebang" line: #!/usr/bin/python
• You can run an app using py: py app.py

Code Layout and Style

• Python uses indentation instead of brackets
• It is advised to use spaces instead of Tabs
• pycodestyle checks your code for compliance with PEP8
• Install pycodestyle with pip: pip install pycodestyle

PEP

• PEP ≡ Python Enhancement Proposal
• A set of documents describing new functions proposals, guidelines, and process descriptions
• PEP20 (The Way of Python) includes 20 principles of Python design

Multi-Paradigm Language

• Python is a multi-paradigm language, allowing structured, object-based, and functional programming
• Python is dynamically-typed, but strongly-typed language

Variables and Output

• Python is dynamically-typed: >>> id = 12, >>> type(id), >>> id = "ad3ez79", >>> type(id)
• print is a function used to output data: >>> print("Hello!"), >>> print("Hello, {}!".format("World"))
• input is a function to read data from input: >>> name = input("Please, type your name:")

Basic Types

• Integer: int, bool
• Floating point: float (double precision)
• Complex numbers: complex (e.g., z: z.real and z.real)
• String: a sequence type (see: next lecture)

Conditions and Functions

• if keyword executes part of the code conditionally
• return keyword returns the result of the function
• def keyword defines a function: def sum(a, b): return a+b

Loops and Objects

• for keyword loops through the values
• range function generates a list of numbers
• Everything in Python is an object, including functions, values, types, and classes