What is OOP programming

Stands for object oriented programming
Instead of being more focussed on functions and procedural abstraction this is more focussed on objects
An object is an data type which uses something called inheritance
4 basics include: abstraction, encapsulation, inheritance and polymorphism

Here is a code snippet from online showcasing OOP OOPye

Data Structures Projects

Tri 3 TT1 Data Structures

Week 2

Replit

Menu.py

self

self as it suggests, refers to itself- the object which has called the method. That is, if you have N objects calling the method, then self.a will refer to a separate instance of the variable for each of the N objects. Imagine N copies of the variable a for each object

init

__init__ is what is called as a constructor in other OOP languages such as C++/Java. The basic idea is that it is a special method which is automatically called when an object of that Class is created

class Example

class receipt():
    def __init__(self,apples,figs,dates):
        self.apples = apples
        self.figs = figs
        self.dates = dates
        self.bill = apples + figs + dates
        print ("Buy",self.apples,"apples", self.figs,"figs 
                and",self.dates,"dates. 
                Total bill is",self.receipt," pieces of fruit")
                
purchase = receipt(5,6,7)

result

> Buy 5 apples 6 figs and 7 dates. Total fruitty bill is 18  pieces of fruit

Replit Week 1

Week 1

Python Lists Vs Dictionaries

List is a collection of index values pairs as that of array in JS. Dictionary is a hashed structure of key and value pairs.

InfoDB Lists

KVDb = []
# List with dictionary records placed in a list  
KVDb.append({  
               "FirstName": "Karthik",  
               "LastName": "Valluri",  
               "DOB": "July 22",  
               "Location": "San Diego",  
               "Personal Email": "karthikv722@gmail.com",  
               "School Email": "karthikv44293@stu.powayusd.com",  
               "Coding_Languages":["Python","JS","CSS","HTML", "Java"]  
              })

Print the second car from Mort’s Owns_Cars list

x = InfoDb[0]["Coding_Languages"][1] 
result: JS

There is also a method called get() on the Dictionary(InfoDb[0]) that will give you the same result:

x = InfoDb[0].get("Coding_Languages")[2]
result: CSS

Print Content from InfoDB

# given an index this will print InfoDb content
def print_data(n):
    print(InfoDb[n]["FirstName"], InfoDb[n]["LastName"])  # using comma puts space between values
    print("\t", "Cars: ", end="")  # \t is a tab indent, end="" make sure no return occurs
    print(", ".join(InfoDb[n]["Owns_Cars"]))  # join allows printing a string list with separator
    print()



def tester():
    print("For loop")
    for_loop()
    print("While loop")
    while_loop(0)  # requires initial index to start while
    print("Recursive loop")
    recursive_loop(0)  # requires initial index to start recursion

While Loop

# while loop contains an initial n and an index incrementing statement (n += 1)
def while_loop(n):
    while n < len(InfoDb):
        print_data(n)
        n += 1
    return

For Loop

# for loop iterates on length of InfoDb
def for_loop():
    for n in range(len(InfoDb)):
        print_data(n)

# menu.py - function style menu
# Imports typically listed at top
# each import enables us to use logic that has been abstracted to other files and folders
import loopy
import mathpy
import funcy
import patterns


# Main list of [Prompts, Actions]
# Two styles are supported to execute abstracted logic
# 1. file names will be run by exec(open("filename.py").read())
# 2. function references will be executed directly file.function()
main_menu = [
    ["Stringy", "stringy.py"],
    ["Listy", "listy.py"],
    ["Loopy", loopy.main],
]

# Submenu list of [Prompt, Action]
# Works similarly to main_menu
sub_menu = [
    ["Factors", mathpy.factors],
    ["GCD", mathpy.gcd],
    ["LCM", mathpy.lcm],
    ["Primes", mathpy.primes],
]

patterns_sub_menu = [
    ["Patterns", "patterns.py"],
    ["PreFuncy", "prefuncy.py"],
    ["Funcy", funcy.ship],
]

# Menu banner is typically defined by menu owner
border = "=" * 25
banner = f"\n{border}\nPlease Select An Option\n{border}"

# def menu
# using main_menu list:
# 1. main menu and submenu reference are created [Prompts, Actions]
# 2. menu_list is sent as parameter to menuy.menu function that has logic for menu control
def menu():
    title = "Function Menu" + banner
    menu_list = main_menu.copy()
    menu_list.append(["Math", submenu])
    menu_list.append(["Patterns", patterns_submenu])
    buildMenu(title, menu_list)

# def submenu
# using sub menu list above:
# sub_menu works similarly to menu()
def submenu():
    title = "Function Submenu" + banner
    buildMenu(title, sub_menu)

def patterns_submenu():
    title = "Function Submenu" + banner
    buildMenu(title, patterns_sub_menu)

def buildMenu(banner, options):
    # header for menu
    print(banner)
    # build a dictionary from options
    prompts = {0: ["Exit", None]}
    for op in options:
        index = len(prompts)
        prompts[index] = op

    # print menu or dictionary
    for key, value in prompts.items():
        print(key, '->', value[0])

    # get user choice
    choice = input("Type your choice> ")

    # validate choice and run
    # execute selection
    # convert to number
    try:
        choice = int(choice)
        if choice == 0:
            # stop
            return
        try:
            # try as function
            action = prompts.get(choice)[1]
            action()
        except TypeError:
            try:  # try as playground style
                exec(open(action).read())
            except FileNotFoundError:
                print(f"File not found!: {action}")
            # end function try
        # end prompts try
    except ValueError:
        # not a number error
        print(f"Not a number: {choice}")
    except UnboundLocalError:
        # traps all other errors
        print(f"Invalid choice: {choice}")
    # end validation try

    buildMenu(banner, options)  # recursion, start menu over again


if __name__ == "__main__":
    menu()


#funcy.py
import time

# terminal print commands
ANSI_CLEAR_SCREEN = u"\u001B[2J"
ANSI_HOME_CURSOR = u"\u001B[0;0H\u001B[2"
OCEAN_COLOR = u"\u001B[44m\u001B[2D"
SHIP_COLOR = u"\u001B[32m\u001B[2D"
RESET_COLOR = u"\u001B[0m\u001B[2D"

def ocean_print():
    # print ocean
    print(ANSI_CLEAR_SCREEN, ANSI_HOME_CURSOR)
    print("\n\n\n\n")
    print(OCEAN_COLOR + "  " * 35)


# print ship with colors and leading spaces
def ship_print(position):
    print(ANSI_HOME_CURSOR)
    print(RESET_COLOR)
    sp = " " * position
    print(sp + "    |\   ")
    print(sp + "    |/   ")
    print(SHIP_COLOR, end="")
    print(sp + "\__ |__/ ")
    print(sp + " \____/  ")
    print(RESET_COLOR)


# ship function, iterface into this file
def ship():
    # only need to print ocean once
    ocean_print()

    # loop control variables
    start = 0  # start at zero
    distance = 60  # how many times to repeat
    step = 2  # count by 2

    # loop purpose is to animate ship sailing
    for position in range(start, distance, step):
        ship_print(position)  # call to function with parameter
        time.sleep(.1)

Github Links

https://github.com/kar722/CSPTri3/blob/main/week0/menu.py

CSP Tri 3