LAST Minutes PYTHON NOTES FOR PGT CS

 

Last Minutes Notes for Python Basics

1. 
   
2. 
   
3. Variables and Data Types:
• Variables store data values.
• Common data types: int, float, str, bool.
• 
  
4. Example:
5. name = "John"
   age = 25
   height = 5.9
   is_student = False

Lists and Tuples:

• Lists are mutable, tuples are immutable.
• Indexing starts at 0.

my_list = [1, 2, 3, 4]

my_tuple = (1, 2, 3, 4)

Control Flow:

• if, elif, and else for conditional statements.
• for and while for loops.

if age < 18:

print("Minor")

elif 18 <= age < 65:

print("Adult")

else:

print("Senior")

Functions:

1. 1.Defining Functions:

def greet(name):

print(f"Hello, {name}!")

greet("Alice")

2.Return Statement:

def square(x):

return x ** 2

result = square(5)

Advanced Concepts:

1. Classes and Objects:

1. class Dog: def __init__(self, name, age): self.name = name self.age = age def bark(self): print("Woof!") my_dog = Dog("Buddy", 3) my_dog.bark()

Inheritance:

class Student(Person): def __init__(self, name, age, student_id): super().__init__(name, age) self.student_id = student_id

Exception Handling:

try: result = 10 / 0 except ZeroDivisionError: print("Cannot divide by zero!") finally: print("This code always runs.")

File Handling:

# Reading from a file with open("example.txt", "r") as file: content = file.read() # Writing to a file with open("example.txt", "w") as file: file.write("Hello, World!")

External Libraries:

1. NumPy:
• For numerical operations.
• import numpy as np array = np.array([1, 2, 3, 4])
• 
  
• Pandas:
• For data manipulation and analysis.
• import pandas as pd df = pd.DataFrame({"Name": ["Alice", "Bob"], "Age": [25, 30]})
• 
  
Matplotlib:
• For data visualization.
• import matplotlib.pyplot as plt plt.plot([1, 2, 3, 4], [2, 4, 6, 8]) plt.show()

Feel free to ask for more specific information or examples!

Dr.Poonam