Course: CSCI 1250

The `if` Statement

Control structure → directs the order of statement execution
- Sequence structure → statements executed in the order they appear
- Decision/Selection structure → executes actions based on a condition

Flowchart Representation

flowchart TD
    A[Start] --> B{Condition}
    B -- True --> C[...]
    B -- False --> D[...]

Python Syntax

if condition:
    # statement(s)

Boolean Variables

References one of two values: True or False
Represented by the bool type in Python
Commonly used for flags, a variable to determine if a condition exists

Boolean Expressions

Tested by the if statement to determine truthiness
- IE: a > b → True if a is greater than b, False otherwise

Relational Operators

> → greater than
< → less than
>= → greater than or equal to
<= → less than or equal to
== → equal to
!= → not equal to

The `not` Operator

Reverses the logical value of a boolean expression
- IE: not False → True (and vise-versa)

Checking Numeric Ranges

To check within a range, use and
- IE: x >= 18 and x <= 21
To check outside a range, use or
- IE: x < 10 or x > 20