3.16 Intro to Simulations - Alexa

  • What is a simulation?
    • A simulation is an imitation of a situation or process
    • Aka a virtual experiment

Guiding questions for a simulation:

- What makes it a simulation?
- What are it’s advantages and disadvantages? 
- In your opinion, would an experiment be better in this situation?

Examples of Simulations:

Simulations are used all the time over many different industries

  • testing safety of a car
  • games
  • testing the efficiency of a parking lot
  • testing a new train route

Simulation vs. Experiment

  • Experiment definition: procedure undertaken to make a discovery, test a hypothesis, or demonstrate a known fact

So, why use a simulation?

  • Advantages:
    • Can be safer
    • More cost-effective
    • More efficient
    • More data in less time
  • Disadvantages:
    • Not as accurate as experiments
    • outside factors not included (ex: in rolling dice simulation gravity and air resistance)
  • When do you not use a simulation?
    • when a situation already has set results/data (won't change)
    • examples: a score in a game, most purchased food, average yearly wage

leads into real life game example:



A Real Life Example: Four Corners - Lydia & Ava

  • an example of a simulation and experiment = the game of 4 corners
  • games are simulations!
  • We are going to play a round of 4 corners here in class.
    • This game is a real life version of our simulation.
    • Mr. Mortensen will be the person in the middle choosing corners.
    • Everyone will choose a corner, and if your corner is chosen, you are out!

The rules of the game:

  1. a person stands in the center of a room and the 4 coners are labeled 1-4
  2. Every player chooses a corner while the person in the middle closes their eyes
  3. person in the middle chooses/calls out a number when instructed
  4. every player in the chosen corner is now out
  5. contine until there is a winner!

Let's play!

Below is the simulation of the four corners game!

import random

status = "in"
while status != "out":
    chooseCorner = input("What corner do you choose?")

    corner = random.randint(1,4)

    if int(chooseCorner) == corner:
        status = "out"
        print("You chose corner number " + chooseCorner + " and you're OUT")
    else:
        print("You chose corner number " + chooseCorner + " and are still in!")
You chose corner number 2 and are still in!
You chose corner number 3 and are still in!
You chose corner number 4 and you're OUT

Comparing Experiment to Simulation Code:

  • Mr. Mortensen (person in the middle) = random.randint
  • if statement = if player is out
  • else = safe/continue
  • while loop = repeats process until there is a winner of the game

DEBRIEF QUESTIONS:

  1. Why is it better to code simulations than experiement in real life?
  2. What makes this game a simulation?
  3. What are its advantages and disadvantages?
  4. Would an experiment be better in this situation? (raise hands for each team)



Hack #1

  • Create an idea for a simulation and describe it (you don’t actually have to code it just think about/answer the guiding questions).

Hack #2 (collegeboard based questions)

  • Simulations Quiz (either screenshot or paste quiz in your notebook):
questions_number = 6
answers_correct = 0
questions = [
    "True or False: Simulations will always have the same result. \n A: True, \n B: False",
    "True or False: A simulation has results that are more accurate than an experiment \n A: True, \n B: False",
    "True or False: A simulation can model real world events that are not practical for experiments \n A: True, \n B: False",
    "Which one of these is FALSE regarding simulations \n A: Reduces Costs, \n B: Is safer than real life experiments, \n C: More Efficient, \n D: More accurate than real life experiments",
    "Which of the following scenarios would be the LEAST beneficial to have as a simulation \n A: A retail company wants to identify the item which sold the most on their website, \n B: A restaurant wants to determine if the use of robots will increase efficiency, \n C: An insurance company wants to study the impact of rain on car accidents, \n D: A sports car company wants to study design changes to their new bike design ",
    "Which of the following is better to do as a simulation than as a calculation \n A: Keeping score at a basketball game, \n B: Keeping track of how many games a person has won, \n C: Determining the average grade for a group of tests, \n D: Studying the impact of carbon emissions on the environment"
]
question_answers = [
    "B",
    "B",
    "A",
    "D",
    "A",
    "D"
]

print("Welcome to the Simulations Quiz!")

def ask_question (question, answer):
    print("\n", question)
    user_answer = input(question)
    print("You said: ", user_answer)

    if user_answer == answer:
        print("Correct!")
        global answers_correct
        answers_correct = answers_correct + 1
    else:
        print("You are incorrect")
    
for num in range(questions_number):
    ask_question(questions[num], question_answers[num])

print("You scored: ", answers_correct, "/6")



Rolling a Dice Example - Sri

Below is a simulation of rolling dice! Examine the code and think about how this simulation works and its purpose!

def parse_input(input_string):
    if input_string.strip() in {"1", "2", "3","4", "5", "6"}:
        return int(input_string)
    else:
        print("Please enter a number from 1 to 6.")
        raise SystemExit(1)

import random

def roll_dice(num_dice):
    roll_results = []
    for _ in range(num_dice):
        roll = random.randint(1, 6)
        roll_results.append(roll)
    return roll_results


num_dice_input = input("How many dice do you want to roll? [1-6] ")
num_dice = parse_input(num_dice_input)
roll_results = roll_dice(num_dice)

print("you rolled:", roll_results) 
you rolled: [5, 1, 2]



Game of Life - Lydia & Ava

Below is a simulation of the Game of Life, originally written by John Horton Conway. Mr. Mortensen has this game on the APCSP site and we think that it is a great example of an interactive simulation.

What it is

  • This game is an unpredictable cellular automaton
  • automaton = simulates and imitates human life, hence why this is called the game of life
  • After creating the initial configuration, the game evolves without pattern

How it works

  • Cells in this game are alive or dead, similar to binary where they are on or off
  • The user created an initial configuration of cells on the grid, and presses play (tap the squares on the grid)
  • a cells's status (alive or dead, on or off) depends on the surrounding 8 cells status (surrounding 8 boxes). Here are the rules:
    • The birth rule= a dead cell (blue box) that is surrounded by at least 3 alive cells (yellow boxes), will become alive
    • The death rule= an alive cell (yellow) with no or only one surviving cell around it dies (becomes blue)
    • Cell survival= an alive cell (yellow) with 2 or 3 alive neighboring cells will stay alive

Try it Out!

Use the grid below to create cell figurations, press play, and watch your cells die, live, and move around!

Remix of Game of Life



Hack #3

  • Describe the rolling dice simulation (answer guiding questions)

Hack #4

  • Add a feature onto the rolling dice simulation above
    • ex: a 14-sided dice or expand the purpose of the simulation (hint: use conditionals to make dice part of a game/real life situation)



Hacks Overview

Use these guiding questions for a simulation:

- What makes it a simulation?
- What are it’s advantages and disadvantages? 
- In your opinion, would an experiment be better in this situation?

Hack #1 (0.3)

  • Create an idea for a simulation and describe it (you don’t actually have to code it just think about/answer the guiding questions).

Hack #2 (0.1)

  • Simulations Quiz (either screenshot or paste quiz in your notebook)

Hack #3 (0.2)

  • Describe the rolling dice simulation (answer guiding questions)

Hack #4 (0.3)

  • Add a feature onto the rolling dice simulation above
    • ex: a 14-sided dice or expand the purpose of the simulation (hint: use conditionals to make dice part of a game/real life situation)

Extra Credit (0.1)

  • For the extra 0.1: try coding a simple simulation and describe it (guiding question)