Python Programming Basics

Hands-on Coding Practice

• Learn to write and execute basic programs using coding concepts.
• Identify and correct common coding errors.

Python Programming Language

• Easy to read and understand.

Writing your First Program

• print("Welcome to Coding!")
  • Prints a simple message to the console.

Basic Programming Structures

• Variables: Store information with various data types.
  • name = "Alice" - Variable name stores the value "Alice".
• Conditional Statements: Allow programs to make decisions.
  • if age >= 18: print("You are an adult.") else: print("You are a minor.")
• Loops: Repeat actions in a program.
  • for i in range(1, 6): print(i) # Prints numbers 1 through 5.

Key Syntax Rules

• Indentation: Defines blocks of code.
  • if 5 > 2: print("Five is greater than two!")
• Comments: Explain code and are ignored by Python.
  • # This is a single-line comment print("Hello, World!")
• Statements: Instructions for Python to execute.
  • x = 5; y = 10; print(x + y) # Multiple statements on one line
• Expressions: Combine values and evaluate to a value.
  • result = 5 + 10 # Evaluates to 15

Important Functions

• input(): Gathers input from the user.
  • name = input("What is your name?")
  • Returns a string.
  • Convert to other data types if needed.
• print(): Displays output to the user.
  • print("Hello, World!")
  • Print multiple items by separating them with commas.
  • print("Name:", name, "Age:", age)

Running Code

• Use "Run" or "Execute" button in the code editor.
• Output appears in a console or output window.

Coding Errors

• Syntax Errors: Code does not follow programming language rules.
  • print("Hello World" # Missing closing parenthesis
• Runtime Errors: Program encounters an issue during execution.
  • x = 10 / 0 - Division by zero.
• Logical Errors: Code produces incorrect results due to logical mistakes.
  • age = 20 if age > 18: print("You are not an adult.")

Debugging

• Finding and fixing errors (bugs).
• Debugging Tips:
  • Read error messages.
  • Check syntax carefully.
  • Test small parts of the code.

Introduction

• This unit focuses on hands-on coding practice.
• Students will write simple programs and receive feedback.
• Learning outcome: Write and execute basic programs, identify and correct errors.

Code in Action

• Python is the programming language used due to its readability.
• Basic program: print("Welcome to Coding!")
• Variables store information in various data types:
  • Example: name = "Alice"
• Conditional statements allow programs to make decisions:
  • Example: if age >= 18: print("You are an adult.")
• Loops repeat actions:
  • Example: for i in range(1, 6): print(i)

Key Syntax Elements

• Indentation defines blocks of code.
• Comments explain code and are ignored by Python.
• Statements are instructions executed by Python.
• Expressions combine values and evaluate to a value.

Input and Output Functions

• input() gathers input from the user, returns a string.
• print() displays output to the user.

Debugging

• Syntax errors occur when code violates language rules.
• Runtime errors happen during program execution, like dividing by zero.
• Logical errors result in incorrect output due to faulty logic.
• Debugging involves finding and fixing errors ("bugs").
• Debugging tips:
  • Read error messages.
  • Check syntax carefully.
  • Test small parts of your code.

Coding in Action

• Python is the chosen programming language for this course due to its readability.
• The code print("Welcome to Coding!") prints a simple message.
• Variables store data using different data types, like name = "Alice".
• Conditional statements enable decision-making in programs, using if and else clauses.
• for loops iterate actions, as demonstrated in for i in range(1, 6): print(i).

Key Syntax Rules

• Indentation determines code blocks, essential for structure.
• Comments are ignored by Python and used for explanations.
• Statements are instructions executed by Python.
• Expressions combine values to evaluate to a single value.

Input and Output Functions

• The input() function gathers user input, returning it as a string. It requires conversion to other data types if needed.
• The print() function displays output to the user, accommodating multiple items separated by commas.

Common Coding Errors

• Syntax Errors: Occur when code violates language rules, like missing parentheses.
• Runtime Errors: Happen during program execution, often from issues like dividing by zero.
• Logical Errors: Lead to incorrect results due to flawed logic within the code.

Debugging Tips

• Pay attention to error messages as they provide clues to the problem.
• Carefully review syntax for correct punctuation and structure.
• Test smaller sections of your code to isolate the source of errors.