Welcome to this comprehensive lesson where we’ll dive into the world of built-in functions and explore essential Python modules. Python provides a rich set of built-in functions that simplify common tasks, and modules extend this functionality for more specialized operations. In this lesson, we’ll explore commonly used functions and take an overview of Python modules, including examples from the math and random modules.
Commonly Used Built-in Functions:
1. len():
- Returns the length of a sequence (e.g., string, list, tuple).
- Example:
text = "Hello, Python!"
length = len(text)
2. print():
- Outputs the specified values to the console.
- Example:
name = "Alice"
age = 25
print("Name:", name, "Age:", age)
3. type():
Returns the data type of an object.
Example:4. input():
- Reads a line from the console and returns it as a string.
- Example:
user_input = input("Enter your name: ")
5. sum():
- Returns the sum of all items in an iterable.
- Example:
numbers = [1, 2, 3, 4, 5]
total = sum(numbers)
Overview of Python Modules – math Module:
6. math.sqrt():
- Returns the square root of a number.
- Example:
import math
result = math.sqrt(25)
7. math.sin() and math.cos():
- Returns the sine and cosine values of an angle (in radians), respectively.
- Example:
import math
angle = math.radians(30) # Convert degrees to radians
sine_value = math.sin(angle)
cosine_value = math.cos(angle)
Overview of Python Modules – random Module:
8. random.randint():
- Returns a random integer between specified boundaries.
- Example:
import random
random_number = random.randint(1, 10)
9. random.choice():
- Returns a randomly selected item from a sequence.
- Example:
import random
colors = ["red", "blue", "green"]
selected_color = random.choice(colors)
10. random.shuffle(): – Shuffles the elements of a sequence randomly. – Example: “`python import random
numbers = [1, 2, 3, 4, 5]
random.shuffle(numbers)
```
Example:
Let’s consider an example where we use the math module to calculate the area of a circle and the random module to generate a random number:
# Example Code
import math
import random
# Using the math module
radius = 7
area = math.pi * math.pow(radius, 2)
# Using the random module
random_number = random.randint(1, 100)
print(f"The area of a circle with radius {radius} is {area}.")
print(f"Randomly generated number: {random_number}")
Practice Exercise:
Create a Python script that asks the user to enter two numbers and then uses the math module to calculate and print the square root of the sum of their squares.
# Example Practice Exercise
import math
# Input from the user
num1 = float(input("Enter the first number: "))
num2 = float(input("Enter the second number: "))
# Using the math module
result = math.sqrt(math.pow(num1, 2) + math.pow(num2, 2))
print(f"The square root of the sum of their squares is: {result}")
Summary:
In this lesson, we’ve explored commonly used built-in functions in Python and introduced the math and random modules. These modules extend Python’s capabilities for mathematical operations and random number generation. Practice using these functions and modules to enhance your coding skills. Feel free to ask questions in the discussion forum, and