Introduction to Python

Course Content

Introduction to Python

Introduction to Python

1. First Acquaintance with Python

The Very First Steps in Python How to Use Comments for Readability Perform Simple Math in Python Handle More Challenging Math in Python Bringing Python Fundamentals Together

2. Variables and Types in Python

How to Store Numbers in Python Python Naming Rules for Variables How to Work with Variables in Python Data Types in Python Challenge: Converting Kilometers to Miles Store Text with Strings in Python String Indexing in Python Negative Indexing and String Length in Python String Slicing in Python Challenge: Retrieving Letters from String String Concatenation in Python

3. Conditional Statements in Python

Boolean Data Type in Python Challenge: Working with Comparison Operators How to Combine Conditions in Python Challenge: Working with Logical Operators Membership Operators and Type Comparisons in Python How to Use if/else Expressions in Python Challenge: Running a Grocery Store Challenge: Creating Odd and Even Logic if/elif/else Expressions Challenge: Running Grocery Store Extended Challenge: Weather Adviser

4. Other Data Types in Python

Python Lists Common List Methods in Python Challenge: Updating List Nested Lists in Python Challenge: Retrieving Information from Nested List Python Tuples Common Tuple Methods in Python Challenge: Updating Tuple Nested Tuples in Python Challenge: Retrieving Information from Nested Tuple Python Dictionaries Challenge: Creating Dictionary Common Dictionary Methods in Python Challenge: Updating Dictionary

5. Loops in Python

Explore the while Loop in Python Challenge: Working with the While Loop Explore the for Loop in Python Challenge: Working with the For Loop Range Function in Python Challenge: Using the Range Function How to Iterate Over Indexes in Python Explore Nested Loops in Python

6. Functions in Python

Built-in Functions in Python Challenge: Converting Heights How to Create Functions in Pythons Challenge: Writing First Function Use of if/else Statements in Python Functions Challenge: Identifying Positive Values Functions Without Return in Python Challenge: Creating Logging Function Modifying Functions in Python Challenge: Updating Logic of the Function Lambda Functions in Python Challenge: Creating Lambda Function

How to Use if/else Expressions in Python

Now that conditional operators are understood, they can be used to branch code based on specific conditions. In Python, this is done using the following structure:

The condition can be a conditional statement or a boolean value, such as a != 4 or b > 100. The commands under if and else are executed based on whether the condition is met. These can include print() statements, variable assignments, arithmetic operations, string manipulations, and more.

Now, let's go through an example: Suppose you have a string and want to check if it's long. A string is considered long if it contains more than 20 characters.


              1234567891011121314151617
            
# Assign some variable
test = "small string"

# Conditional statement
if len(test) > 20:
    print("This string is long!")
else:
    print("Nothing special")
    
# Check on different string
test = "This string is very-very and very large"

# Conditional statement
if len(test) > 20:
    print("This string is long!")
else:
    print("Nothing special")

Note

Remember, the code blocks under if and else must have consistent indentation (e.g., 2 spaces, 4 spaces, etc.).

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Section 3. Chapter 6

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