Lesson Overview: 3.5 - Boolean Expressions

  • Here we will focus on:
    • basics of Booleans
    • its relationship with binary
    • relational operators
    • Logical Operators

What is a boolean?

  • A data type with two possible values: true or false

Boolean and Binary

So similar yet so different.

  • Boolean math and binary notation both use the same two ciphers: 1 and 0.
  • However, please note that Boolean quantities are restricted to a singlular bit (can only be either 1, or 0)
  • On the otherhand, binary numbers may be composed of many bits adding up in place-weighted form to any finite value, or size

Must Knows

  • A Boolean value is either TRUE or FALSE
  • The AP Exam will provide you with a reference sheet with the operators below.
  • A few ways these operators could be used...

Relational Operators in action

  • How could you use operators to determine if the average of 5 grades is greater than 80?
  • With the grades below, use a boolean expression to determine if the average grade is above an 80 and print the result (True or False)
  • Try it in as few steps as possible!
  • Be creative! There are obviously TONS of different practical solutions
grade1 = 90
grade2 = 65
grade3 = 60
grade4 = 75
grade5 = 95
gradeAvg = (grade1+grade2+grade3+grade4+grade5)/5
print(gradeAvg > 80)
False

The versatility of relational operators:

print("100 == 100:",100==100)
print("Hello == Adios:","greeting"=="farewell")
print("Hello != Adios:","greeting"!="farewell")
print("Hello == Hola:","greeting"=="greeting")
print("5>=4:", 5>=4)
print ('')

# Notice that relational operators can even work on lists!
# For lists, the relational operator compares each respective component until an answer is derived

print("['a','b','c'] > ['x','y','z']:", ['a','b','c'] > ['x','y','z'])
print("[1,2,3,5] > [1,2,3,4]:", [1,2,3,5] > [1,2,3,4])
print("[1,2,3,5] < [1,2,3,4]:", [1,2,3,5] < [1,2,3,4])
print("[1,2,3,5] == [1,2,3,4]:", [1,2,3,5] == [1,2,3,4])
100 == 100: True
Hello == Adios: False
Hello != Adios: True
Hello == Hola: True
5>=4: True

['a','b','c'] > ['x','y','z']: False
[1,2,3,5] > [1,2,3,4]: True
[1,2,3,5] < [1,2,3,4]: False
[1,2,3,5] == [1,2,3,4]: False

Logical Operators!

These types of operators don't necessarily deal with equivalent/non-equivalent values, but they rather work on operands to produce a singular boolean result

  • AND : returns TRUE if the operands around it are TRUE
  • OR : returns TRUE if at least one operand is TRUE
  • NOT : returns TRUE if the following boolean is FALSE

Turn the following arithmetic phrases into either True or False statements as indicated USING LOGICAL OPERATORS

print("1 > 2 or 5 < 12:", 1 > 2 or 5 < 12)
# Output TRUE  using OR ^


# Output FALSE using NOT
print("24 > 8:",24 > 8)

# Output FALSE using AND
print("10 > 20:", 10 > 20 and False)
1 > 2 or 5 < 12: True
24 > 8: True
10 > 20: False

Lesson Overview: 3.6 - Conditionals

Focusing on Selection

Selection: uses a condition that evaluates to true or false

Selection determines which part of an algorithm are executed based on a condition being true or false

Algorithm is a finite set of instructions that accomplish a specific task

Conditional Statements

Also known as "if statements"

Can be seen as if statements or if blocks

Can also be seen as if else statements or if else-blocks

x = 20
y = 10
if x > y:
    print("x is greater than y")
x is greater than y
x = 9
y = 10
if x > y:
    print("x is greater than y")
else:
    print("x is not greater than y")
x is not greater than y

Participation

-Calculate the total sum of two numbers, if it is equal to 200, print 200, if otherwise, print the sum.

num1 =103
num2 = 97
sum = num1 + num2
if sum == 200:
	print(sum)
else:
	print(sum)
200

Lesson Overview - 3.7 Nested Conditionals

  • Nested conditional statements consist of conditional statements within other conditional statements
  • Utilizes "if else" statements within "if else" statements
  • Basics of a nested conditional:
  • Block Coding Visual of Nested Conditionals:

  • Example Psuedocode of Nested Conditional Statements

Analyzing Code Walkthrough

  • Psuedocode to the left, block code to the right
  • Approach the problem by going through each condition one at a time

    • Decide which ones are false to skip and which ones are true to execute
  • You Try:

score = 82
if (score >= 90)
{
    console.log("You got an A, congrats!")
}
else
{
    if (score >= 75)
    {
        console.log("Please come to retake up to a 90 next week at tutorial!")
    }
    else
    {
        console.log("You have detention!!")
    }
}
Please come to retake up to a 90 next week at tutorial!
protein = 25
carbs = 36
sugar = 11
if (carbs >= 55 || protein <= 20 || sugar >= 15)
{
    console.log("Your lunch is too unhealthy, please pick a new one")
}
else
{
    if (carbs < 35 || protein < 25)
    {
    console.log ("This lunch is alright but try to add some more carbs or protein")
    }
    else 
    {
    if (sugar >= 11)
    {
    console.log ("Looks great but lets see if we can cut down on sugar, we don't want diabetes!")
    }
    else
    {
        console.log ("Amazing, you created a healthy lunch!!!")
    }
    }
}
Looks great but lets see if we can cut down on sugar, we don't want diabetes!

Writing Nested Code Activity

  1. Write a program that fits these conditions using nested conditionals:
    • If a person has at least 8 hours, they are experienced
    • If a person is experienced their salary is 90k, if they have ten hours or above their salary 150k
    • If a person is inexperienced their salary is always 50k
    • print the salary of the person at the end and whether they are experienced or not

Hacks Assignments:

Conditionals:

  • Write a program that fits these conditions using nested conditionals:
    • If the product is expired, print "this product is no good"
    • If the cost is above 50 dollars, and the product isn't expired, print "this product is too expensive"
    • If the cost is 25 dollars but under 50, and the product isn't expired, print "this is a regular product"
    • If the cost is under 25 dollars, print "this is a cheap product"
experience = 10
salary = 100000

if (experience> 10){
	console.log("you are experienced")
}
else{
	if (experience >=10){
		console.log("Experienced, Salary is 150k.")
	}
	else{
		console.log("Experienced salary is 90k")
	}
}
Experienced, Salary is 150k.
//True = product is expired, false =  product isn't expired
productStatus = false
cost = 700000

if (productStatus){
	console.log("This product is no good")
}
else{
	if(cost > 50 ){
		console.log("this product is too expensive")
	}
	if(cost < 50 && cost> 25)
		console.log("this is a regular product")
	if (cost<25){
		console.log("this is a cheap product")
	}
}
this product is too expensive
import getpass, sys
    
def question_with_response(prompt):
    print("Question: " + prompt)
    msg = input(prompt)
    return msg

questions = 3
correct = 0

print('Hello, ' + getpass.getuser())
print("You will be asked " + str(questions) + " questions.")
print("Are you ready for this World Cup Quiz? Let's start!")

rsp = question_with_response("Who won the 2010 World Cup?: A. Argentina B. Germany C. Spain D. Uruguay")
if rsp == "Spain" or rsp == "C":
    print(rsp + " is correct!")
    correct += 1
else:
    print(rsp + " is incorrect!")

rsp = question_with_response("Who won the 2014 World Cup?: A. Germany B. Brazil C. Argentina D. Netherlands")
if rsp == "Germany" or rsp == "A":
    print(rsp + " is correct!")
    correct += 1
else:
    print(rsp + " is incorrect!")

rsp = question_with_response("Who won the 2018 World Cup?: A. England B. Belgium C. Germany D. France")
if rsp == "France" or rsp == "D":
    print(rsp + " is correct!")
    correct += 1
else:
    print(rsp + " is incorrect!")

print(getpass.getuser() + " you scored " + str(correct) +"/" + str(questions))
Hello, yuri
You will be asked 3 questions.
Are you ready for this World Cup Quiz? Let's start!
Question: Who won the 2010 World Cup?: A. Argentina B. Germany C. Spain D. Uruguay
C is correct!
Question: Who won the 2014 World Cup?: A. Germany B. Brazil C. Argentina D. Netherlands
A is correct!
Question: Who won the 2018 World Cup?: A. England B. Belgium C. Germany D. France
D is correct!
yuri you scored 3/3

Boolean/Conditionals:

  • Create a multiple choice quiz that ...
    • uses Boolean expressions
    • uses Logical operators
    • uses Conditional statements
    • prompts quiz-taker with multiple options (only one can be right)
    • has at least 3 questions
  • Points will be awarded for creativity, intricacy, and how well Boolean/Binary concepts have been intertwined