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Introduction to Python
course content

Course Content

Introduction to Python

Introduction to Python

1. First Acquaintance
The Very First StepsCommentsSome Simple MathMore Challenging MathChallengeBringing It All Together
2. Variables and Types
Storing NumbersNaming RulesUsing VariablesData TypesNumbersChallengeStoring TextString IndexingNegative Indexing and LengthString SlicingChallengeConcatenation
3. Conditional Statements
Boolean Data TypeChallenge: Comparison OperatorsCombining ConditionsChallenge: Logical OperatorsMembership Operators and Types ComparisonSimple if/else ExpressionsChallenge: Grocery StoreChallenge: Odd and Evenif/elif/else ExpressionsChallenge: Grocery Store ExtendedChallenge: Positive, Negative or Zero
4. Other Data Types
What Is a List?List MethodsChallengeNested ListsChallengeWhat Is a Tuple?Tuple MethodsChallengeNested TuplesChallengeWhat Is a Dictionary?ChallengeDictionary MethodsChallenge
5. Loops
while LoopChallengefor LoopChallengeRangeChallengeIterating Over IndexesNested Loops
6. Functions
Built-in FunctionsChallengeDefining Your First FunctionChallengeif/else Statements in FunctionsChallengeFunctions With No ReturnChallengeModifying FunctionsChallengeLambda FunctionsChallenge

bookwhile Loop

Often, in programming, you want your code to run repeatedly as long as a specific condition is true. Think about how, in everyday life, we stay on a subway train until we reach our designated stop. If our destination is "Station B," we'll pass by "Station A," "Station C," and so forth until we arrive at "Station B." In Python, you can simulate this behavior with a while loop, structured like this:

For instance, we can use this loop to print all numbers up to 10.


              
1234567

            
# Assign starting number (counter)
i = 1

# While loop will print all the numbers to 10
while i < 10: # Condition
  print(i, end = ' ') # Action
  i = i + 1 # Increasing variable
copy

Note

By default, the print() function outputs each result on a new line. By employing the end=' ' argument, we ensure that multiple print() outputs are separated by a space. We'll be using this technique throughout this section.

The loop's logic is outlined above. You might observe that we've included i = i + 1 within the loop. Without this line, our loop would run indefinitely because each time the condition is checked, it would find 1 < 10, which is always True. So, when working with while loops, it's crucial to ensure your code doesn't enter an endless loop.

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Section 5. Chapter 1
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