Python Programming Language Notes

(Only scant, random, scattered main topics here. Not detailed or comprehensive)

ABOUT Python Code:

• Versatile - Works on Windows, Mac, Linux, Supports Object-Oriented and Structured programming 
• High level - Uses natural language to present abstract programming functions
• Dynamically typed - Variable types change, based on the data they hold rather than being declared statically on creation
• Multiple libraries - Open source, easily accessible, many modules containing predefined definitions for easy functionality
• Incompatibility - 3.x incompatible with 2.x code
• Importing modules - import x, import x as y, from x import functional1, from x import *, dir(x)
• Scope - indentation
• Global scope - accessible by whole program, will persist until program runs
• Meaningful indentation - indentation deleanates change in scope (more indentated to left means narrower), each segment of indentation is equal to 4 spaces (don't use tabs) 

NAMING Conventions:

• Uppercase vs. lowercase - Class names are uppercase, all others are lowercase
• Leading underscores - Underscore before name is privatization. Function names that begin with 1 will not be imported when using the "from x import*" statement 
• Trailing underscores - Single underscore after name is used to avoid naming conflicts. A double underscore after a name is used in conjuction with a double underscore before a name to indicate name with a special function 
• Reserved keywords - Some words have special function, and can not be used to name variables, functions or classes (examples: and, as, assert, break, class, continue, def, del, elif, else, except, exec, False, finally, for, from, global, if, import, in, is, lambda, None, nonlocal, not, or, pass, print, raise, return, True, try, while, with, yield)
• Comments - explain in plain language
• Triple quotation marks - docstring to explain purpose
• Pound sign - Comments using # sign when describing how, why, what of code

WRITING Code Basics:

• Making variables - Declaration and assignment, assigning variables
• Types - Integer, Floating point (float), Complex, String, List, Tuple, Boolean (bool), Dictionary (Dict), Changing types 
• Console - Outputting text, taking user input
• Error handling - try, except, else, finally, raise
• Saving and loading files - open(filename, mode), file.read(size), file.readline(), file.write(), file.close()

Coding STRUCTURES:

• List operations - List, tuple, & dict
• Math operators - (int, float & complex)
• Strings - test values without any meaning (mathematical or logical)
• Statements - commands that initiate operation. Boolean, For, While, 
• Functions - used to break down operations into smaller, reusable chunks
• Dictionaries - special list types that contain key value pairs. 2 dimensional arrays with unique identifier keys attached to values

USING Structures:

• String formatting - Using, Returns, Other formatting options
• String methods - Slicing, reversing, splitting, joining, enumerating
• Escape sequences - newline, printing special characters literally
• Bool characters - used to perform operations related to true and false statements
• Writing Boolean statements - Alternate if-else, Nesting if
• Recursion & iteration - Recursion, Iteration, Break, Continue, 
• Classes - Creating, filling

Coding CONCEPTS: 

• Inheritance - Process by which objects gain properties of other objects. Classes, for example. 1st - Parent class. 2nd - Child class. Children can overwrite the inherited properties of their parent, changing functionality. Overriding. Inheritance from multiple parents.