Boolean_Expressions_and_Comparisons_Python.pptx

Boolean expression and comparison

1. Evaluating Boolean Expressions and Making Comparisons College Level | Python Examples | Logical & Relational Operators | Precedence Rules

2. Learning Objectives • Understand Boolean logic • Use relational and logical operators • Apply precedence rules • Create complex conditional expressions

3. What Are Boolean Expressions? Expressions that evaluate to either True or False. Example: >>> 5 > 3 → True >>> 10 == 2 → False

4. Boolean Data Type Python has bool type with two values: True and False. >>> type(True) → <class 'bool'>

5. Importance of Boolean Logic Used for decision making, comparisons, loops, and validations.

6. Relational Operators Used to compare values. ==, !=, >, <, >=, <= Example: >>> 7 >= 5 → True

7. Chained Comparisons Python allows chained expressions: >>> 10 < x < 20 → True if x between 10 and 20.

8. Logical Operators `and`, `or`, and `not` combine boolean results. Example: >>> x > 5 and y < 10

9. Truth Tables AND: True if both True OR: True if either True NOT: Inverts value

10. Short-Circuit Evaluation Python stops evaluating as soon as result is known. >>> False and print('skip') → doesn’t print.

11. Combining Logical & Relational Example: >>> age > 18 and status == 'student'

12. Range-Based Selections Check if values fall within ranges. Example: >>> if 70 <= marks < 80: grade = 'B'

13. Using if-elif-else Example: if score >= 90: grade = 'A' elif score >= 75: grade = 'B'

14. Operator Precedence NOT > AND > OR Relational before Logical. Parentheses can override order.

15. Example on Precedence >>> not 5 > 3 and 2 == 2 → False Evaluated as: not(True) and True → False

16. Associativity Defines direction of evaluation. Most operators are left-associative.

17. Complex Expression Example: result = (a > b and not c) or (d == e and f != g)

18. Boolean Algebra Simplification Simplify logical code using algebraic laws. Ex: not(not A) = A

19. Bitwise vs Logical Bitwise (&, |) works on bits. Logical (and, or) works on boolean values.

20. Common Errors Using '=' instead of '==' Misplaced parentheses Mixing bitwise and logical ops

21. Case Study Example: Access control if user=='admin' and not blocked: allow_access()

22. Recap • Relational: ==, !=, >, <, >=, <= • Logical: and, or, not • Use parentheses to control precedence.

23. Quiz 1. What is the result of not(True or False)? 2. Evaluate: 5>3 and 2==4 3. Explain short-circuit evaluation.

24. References Python Docs | W3Schools | GeeksforGeeks | RealPython Tutorials