Activity 1.1

Fundamental Programming Operations

Topics

• print() for displaying output
• Data Types
• Integer and float data types
• String data type
• Variables
• Arithmetic Operations
• Comments

The print() Function

print() is a function that displays a message in an application.

1
print("Hello world!")

The print() Function

print() is a function that displays a message in an application.

1
print("Hello world!")

Hello world!

Demo: Display a message using print()

1
print("I love Python!")

I love Python!

Passing Multiple Arguments

Use commas to separate the arguments you pass into the print() function.

1
print("Students:", "Anthony,", "Bob")

Students: Anthony, Bob

Data Types

A classification that defines the kind of data a variable can hold.

Integer and Float Data Types

In python, numbers are classified as either integers or floating-point (decimal) values.

Demo: Print Some Numbers

Use the print() function to display some numbers on the screen.

1
print(-1953)
2
print(1_000_000)

The String data type

The string data type represents a sequence of characters used for text.

Double Quotes: "Hello friend."

Single Quotes: 'Mortimer rules'

I am happy! "I am sad!

Format String (f-string)

Special strings that you easily insert code inside text by using curly braces ({ }).

1
print(f"I am 35 years old, which is {35 * 12} months.")

Format String (f-string)

Special strings that you easily insert code inside text by using curly braces ({ }).

1
print(f"I am 35 years old, which is {35 * 12} months.")

1
I am 35 years old, which is 420 months.

Introduction to Variables

Variables allow us to store data during our program's execution. Sometimes, variables are described as containers for storing information.

Declaring a Variable

You can create a variable and assign it a value whenever you need one.

Declaring a Variable

A variable can be used anywhere a typical value would be used.

1
health = 100
2
print("Health:", health)

1
Health: 100

The Assignment Operator

The equal sign (=) used to assign a value to a variable.

It is not used to check for equality; it is only used for assigning a value to a variable.

Variable Scope

Variables must be declared before they can be used.

1
print("Health:", health)
2
health = 100

Demo: Declare and Use Variables

1
score = 14000
2
lives = 3
3
vehicle = "Motorcycle"
4

5
print(vehicle)
6
print("Lives left:", lives)
7
print("Score:", score)

Demo: Declare and Use Variables

1
score = 14000
2
lives = 3
3
vehicle = "Motorcycle"
4

5
print(vehicle)
6
print("Lives left:", lives)
7
print("Score:", score)

1
Motorcycle
2
Lives left: 3
3
Score: 14000

Naming Rules and Conventions

Variables names cannot:

• Contain spaces
• Start with a number

1st; first name;

For names containing multiple words, use snake_case.

Math Operators

+ Addition

- Subtraction

* Multiplication

** Exponents (2**3)

/ Float Division: Divides two numbers and returns the quotient as a decimal.

// Integer Division: Divides two numbers and returns the quotient as an integer.

% Modulus (Mod): Divides two numbers and returns the remainder.

Order of Operations

Use parenthesis for operator precedence.

3 * 4 + 5

3 * (4 + 5)

Demo: Evaluate Some Math Expressions

1
x = 5
2
y = 2
3
z = 4 * 5
4
print(x * 10.2)
5
print(x + y)
6
print(10 % y)
7
print(z)

51
7
0
20

# Comments

Comments serve two key roles: documenting code and disabling it temporarily for testing.

1
# This line prints a friendly greeting to the console
2
print("Hello, world!")
3

4
# print("This line is disabled for testing purposes.")

# Comments

Comments are completely ignored when the program is executed.

1
# This line prints a friendly greeting to the console
2
print("Hello, world!")
3

4
# print("This line is disabled for testing purposes.")

Hello, world!

Key Terms

Data Type

A classification that defines the kind of data a variable can hold, such as numbers and text.

String

A sequence of characters enclosed in quotes, used to represent text in a program.

Integer (int)

A whole number without a fractional or decimal component, such as 3 or -42.

Float (floating-point)

A number that contains a decimal point, used to represent values requiring precision, such as 3.14 or -0.5.

Key Terms

Variable

A named container that stores a value which can be used or changed during program execution.

Assignment Operator (=)

The symbol used to give a variable a value; for example, x = 5 assigns 5 to x.

Arithmetic Operation

A mathematical calculation performed using operators such as +, -, *, /, **, or %.

f-string (formatted string)

A string literal that allows embedded expressions inside curly braces, evaluated at runtime for cleaner output formatting.

Key Terms

print() Function

A built-in Python function that displays text or data on the screen.

Comment

Text in code that Python ignores, used to explain what the program does or to disable code temporarily; written with a # symbol.