Control structures

The if statements are used for conditional execution, allowing a block of code to run only if a specified condition is true (e.g., if temperature > 30: print "It's hot!"). This is done to create decision-making logic in your programs.

age = 72
bp = 145

if age >= 60 and bp > 140:
    print("High-risk: Schedule follow-up consultation.")
elif age >= 60 and bp <= 140:
    print("Monitor regularly.")
else:
    print("Low-risk: Maintain routine check-ups.")

The code above helps automatically classify patients based on age and blood pressure readings, similar to decision rules used in clinical triage systems.

for loops are employed for iteration, repeating a block of code a fixed number of times or for each item in a collection (e.g., for item in list_of_items: process item). They are crucial for automating repetitive tasks.

Loop through a list

patients = ["Alice", "Bob", "Carlos"]
for name in patients:
    print(f"Processing lab report for {name}")

# Output
# Processing lab report for Alice
# Processing lab report for Bob
# Processing lab report for Carlos

This loop ensures that all patient reports are processed without manual repetition—useful when automating data cleaning or report generation for large datasets.

Loop through a range of numbers

for i in range(5):  # 0 to 4
    print(f"Count: {i}")

# Output:
# Count: 0
# Count: 1
# Count: 2
# Count: 3
# Count: 4

Loop through a dictionary

student = {"name": "Alice", "age": 20, "is_diabetic": True}
for key, value in student.items():
    print(f"{key}: {value}")

# Output
# name: Alice
# age: 20
# is_diabetic: True

when (often found in languages like switch in R) is a construct for multi-way branching, providing a cleaner alternative to nested if-else if statements when you have multiple possible conditions to check against a single value (e.g., when day_of_week: "Monday" -> print "Start of the week"). This improves code readability and maintainability.

Basic ‘while’ loop

count = 0
while count < 5:
    print(f"Count is {count}")
    count += 1

‘while’ loop with user input

user_input = ""
while user_input != "quit":
    user_input = input("Enter a command (or 'quit' to exit): ")
    if user_input != "quit":
        print(f"You entered: {user_input}")

Functions are reusable blocks of code designed to perform a specific task (e.g., def calculate_area(length, width): return length * width). They are used to break down complex problems into smaller, manageable pieces, promote code reusability, and improve the organization and readability of your programs.

Basic function

def greet(name):
    return f"Hello, {name}!"

Function with default parameters

def introduce(name, age=25):
    return f"Hi, I'm {name} and I'm {age} years old."

Function with multiple parameters

def calculate_area(length, width):
    area = length * width
    return area

Using functions

message = greet("Alice")
print(message)  # Hello, Alice!

intro = introduce("Bob")  # Uses default age
print(intro)              # Hi, I'm Bob and I'm 25 years old.

room_area = calculate_area(10, 12)
print(f"Room area: {room_area} square feet")

This function encapsulates a clinical rule (BMI categories), demonstrating how logic and computation combine to yield meaningful interpretations in healthcare analytics.

def classify_bmi(weight_in_kg, height_in_meters):
    bmi = weight_in_kg / (height_in_meters ** 2)
    if bmi < 18.5:
        return "Underweight"
    elif bmi < 25:
        return "Normal"
    elif bmi < 30:
        return "Overweight"
    else:
        return "Obese"

print(classify_bmi(70, 1.75))