WEEK 4 Programs

 

WEEK 4 Programs:

 

1. Command Line / Terminal (Most Common)

Save your program in a file, e.g., program.py.

 

• Open a terminal/command prompt.
• Navigate to the folder where the file is saved:

·         cd path/to/your/file

Run the file:

·         python program.py

(Use python3 instead of python on Linux/Mac if needed.)

2. IDLE (Python’s Built-in IDE)

·         Open IDLE (comes with Python).

·         Go to File → Open… and select your .py file.

·         Press F5 (or Run → Run Module).

·         Output will appear in the IDLE shell.

3. VS Code (Visual Studio Code)

·         Install VS Code.

·         Install Python Extension (by Microsoft).

·         Open your .py file in VS Code.

·         Run:

o    Press Run ▶ in the top right corner.

o    Or use terminal inside VS Code:

bash

python program.py

 

4. PyCharm

·         Install PyCharm.

·         Open a new project or import your existing one.

·         Right-click your Python file → Run 'program'.

·         Output shows in PyCharm’s console.

 

5. Jupyter Notebook

·         Install Jupyter:

bash

pip install notebook

·         Start it:

bash

jupyter notebook

·         A browser window opens → you can open .ipynb or create a new notebook.

·         To run .py files:

python

%run program.py

 

6. Google Colab (Online)

·         Open Google Colab.

·         Upload your .py file or copy-paste the code.

·         Run a cell with:

python

!python program.py

·         Great for cloud execution (no installation needed).

7. Anaconda / Spyder

·         Install Anaconda (includes Spyder IDE).

·         Open Spyder → open your .py file.

·         Click Run ▶

·         Output appears in Spyder’s console.

ü  For beginners → IDLE or VS Code.

ü  For data science → Jupyter Notebook / Colab.

ü  For advanced development → PyCharm / VS Code.

ü  For quick testing → Command Line.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 NOTE:

·         For 1^st  to 3^rd  Program write a separate program in notepad and save it with source.txt and sorted_words.txt

·         Save that file in drive with separate folder and upload it in Google colab        

·         Now write a program in Google colab and run you will get your output

 

Program

1. Write a program to sort words in a file and put them in another file. The output file should have only lower-case words, so any upper-case words from source must be lowered.

 CODE:

 

# Create a source.txt file with some words

with open("source.txt", "w") as f:

    f.write("Apple orange Banana grape Cherry Mango Kiwi")

 

# Program to read words from a file, sort them, and write to another file in lowercase

 

# Input and output file names

input_file = "source.txt"

output_file = "sorted_words.txt"

 

# Step 1: Read all words from the input file

with open(input_file, "r") as f:

    text = f.read()

 

# Step 2: Convert text to lowercase and split into words

words = text.lower().split()

 

# Step 3: Sort words alphabetically

words.sort()

 

# Step 4: Write sorted words into the output file

with open(output_file, "w") as f:

    for word in words:

        f.write(word + "\n")

 

print("Words have been sorted and saved in", output_file)

 

OUTPUT:

Words have been sorted and saved in sorted_words.txt

 

# Display the sorted words file

with open("sorted_words.txt", "r") as f:

    print(f.read())

 

OUTPUT:

apple

banana

cherry

grape

kiwi

mango

orange

 

2. Python program to print each line of a file in reverse order.

 CODE:

# Program to print each line of a file in reverse order

 

# Input file name

input_file = "source.text.txt" # Corrected filename

 

# Open and read file

with open(input_file, "r") as f:

    lines = f.readlines()

 

# Print each line in reverse

print("Reversed lines:\n")

for line in lines:

    # Strip newline, reverse, then print

    print(line.strip()[::-1])

 

 

(Optional) — Save reversed lines into another file

output_file = "reversed.txt"

 

with open(output_file, "w") as f:

    for line in lines:

        f.write(line.strip()[::-1] + "\n")

 

print(f"Reversed lines saved in {output_file}")

 

 

OUTPUT:

Reversed lines:

 

elppA

ananab

yreehc

iwik

eparg

 

 

3. Python program to compute the number of characters, words and lines in a file.

 

CODE:

 # Input file name

filename = "source.txt"

 

# Initialize counters

num_lines = 0

num_words = 0

num_chars = 0

 

# Open and read file

with open(filename, "r") as f:

    for line in f:

        num_lines += 1

        num_words += len(line.split())

        num_chars += len(line)

 

# Display the results

print("Number of lines:", num_lines)

print("Number of words:", num_words)

print("Number of characters:", num_chars)

 

 

OUTPUT:

Number of lines: 5

Number of words: 5

Number of characters: 34

 

Explanation:

·         len(line.split()) → counts words in a line.

·         len(line) → counts all characters including spaces and newline (\n).

·         num_lines += 1 → counts total lines.

 

 

4. Write a program to create, display, append, insert and reverse the order of the items in the array.

 CODE:

from array import array

 

# Step 1: Create an array of integers

arr = array('i', [10, 20, 30, 40, 50])

print("Original array:", arr.tolist())

 

# Step 2: Display array elements

print("Array elements:")

for i in arr:

    print(i, end=" ")

print()

 

# Step 3: Append an element

arr.append(60)

print("\nAfter appending 60:", arr.tolist())

 

# Step 4: Insert an element at a specific position

arr.insert(2, 25)  # insert 25 at index 2

print("After inserting 25 at index 2:", arr.tolist())

 

# Step 5: Reverse the array

arr.reverse()

print("After reversing:", arr.tolist())

 

OUTPUT:

Original array: [10, 20, 30, 40, 50]

Array elements:

10 20 30 40 50

 

After appending 60: [10, 20, 30, 40, 50, 60]

After inserting 25 at index 2: [10, 20, 25, 30, 40, 50, 60]

After reversing: [60, 50, 40, 30, 25, 20, 10]

 

Explanation

·         array('i', [...]) → creates an integer array.

·         append() → adds an item at the end.

·         insert(index, value) → inserts at a specific index.

·         reverse() → reverses the array in place.

·         tolist() → converts the array to a normal Python list for easy printing.

 

 

5. Write a program to add, transpose and multiply two matrices.

 CODE:

# Program to add, transpose, and multiply two matrices

 

# Step 1: Define two matrices

A = [

    [1, 2, 3],

    [4, 5, 6],

    [7, 8, 9]

]

 

B = [

    [9, 8, 7],

    [6, 5, 4],

    [3, 2, 1]

]

 

# Step 2: Matrix Addition

add_result = [[A[i][j] + B[i][j] for j in range(len(A[0]))] for i in range(len(A))]

 

# Step 3: Transpose of Matrix A

transpose_A = [[A[j][i] for j in range(len(A))] for i in range(len(A[0]))]

 

# Step 4: Matrix Multiplication (A × B)

multiply_result = [[sum(A[i][k] * B[k][j] for k in range(len(B))) for j in range(len(B[0]))] for i in range(len(A))]

 

# Step 5: Display Results

print("Matrix A:")

for row in A:

    print(row)

 

print("\nMatrix B:")

for row in B:

    print(row)

 

print("\nAddition of A and B:")

for row in add_result:

    print(row)

 

print("\nTranspose of A:")

for row in transpose_A:

    print(row)

 

print("\nMultiplication of A and B:")

for row in multiply_result:

    print(row)

 

OUTPUT:

 

Matrix A:

[1, 2, 3]

[4, 5, 6]

[7, 8, 9]

 

Matrix B:

[9, 8, 7]

[6, 5, 4]

[3, 2, 1]

 

Addition of A and B:

[10, 10, 10]

[10, 10, 10]

[10, 10, 10]

 

Transpose of A:

[1, 4, 7]

[2, 5, 8]

[3, 6, 9]

 

Multiplication of A and B:

[30, 24, 18]

[84, 69, 54]

[138, 114, 90]

 

Explanation

·         Addition: Add elements at the same positions.

·         Transpose: Swap rows with columns.

·         Multiplication: Use dot product of rows and columns.

 

 

6. Write a Python program to create a class that represents a shape. Include methods to calculate its area and perimeter. Implement subclasses for different shapes like circle, triangle, and square.

 CODE:

Program: Shape Class with Subclasses

 

import math

 

# Base class

class Shape:

    def area(self):

        return 0

   

    def perimeter(self):

        return 0

 

 

# Subclass: Circle

class Circle(Shape):

    def __init__(self, radius):

        self.radius = radius

 

    def area(self):

        return math.pi * self.radius ** 2

 

    def perimeter(self):

        return 2 * math.pi * self.radius

 

 

# Subclass: Square

class Square(Shape):

    def __init__(self, side):

        self.side = side

 

    def area(self):

        return self.side ** 2

 

    def perimeter(self):

        return 4 * self.side

 

 

# Subclass: Triangle

class Triangle(Shape):

    def __init__(self, a, b, c):

        self.a = a

        self.b = b

        self.c = c

 

    def perimeter(self):

        return self.a + self.b + self.c

 

    def area(self):

        # Using Heron's Formula

        s = self.perimeter() / 2

        return math.sqrt(s * (s - self.a) * (s - self.b) * (s - self.c))

 

 

# ---- Test the classes ----

 

# Create objects

circle = Circle(5)

square = Square(4)

triangle = Triangle(3, 4, 5)

 

# Display results

print("Circle: Area =", round(circle.area(), 2), "Perimeter =", round(circle.perimeter(), 2))

print("Square: Area =", square.area(), "Perimeter =", square.perimeter())

print("Triangle: Area =", round(triangle.area(), 2), "Perimeter =", triangle.perimeter())

 

 

OUTPUT:

Circle: Area = 78.54 Perimeter = 31.42

Square: Area = 16 Perimeter = 16

Triangle: Area = 6.0 Perimeter = 12

 

Concepts Used

• Base class (Shape) defines common methods (area() and perimeter()).
• Subclasses (Circle, Square, Triangle) override these methods.
• Heron’s formula is used to calculate the triangle’s area.