readwrite practice

import json
import pandas as pd

# File Read and Write Operations

# 1. Read from a file
with open('example.txt', 'r') as file:
    content = file.read()
    print(content)

# 2. Write to a file
with open('output.txt', 'w') as file:
    file.write("Hello, World!")

# JSON

# 3. Read JSON from file
with open('data.json', 'r') as file:
    data = json.load(file)
    print(data)

# 4. Write JSON to file
data = {"name": "John", "age": 30}
with open('output.json', 'w') as file:
    json.dump(data, file, indent=4)

# Pandas

# 5. Read CSV into DataFrame
df = pd.read_csv('data.csv')
print(df)

# 6. Write DataFrame to CSV
df.to_csv('output.csv', index=False)

# 7. Read Excel into DataFrame
df = pd.read_excel('data.xlsx')
print(df)

# 8. Write DataFrame to Excel
df.to_excel('output.xlsx', index=False)

# CSV

# 9. Read CSV file
with open('data.csv', 'r') as file:
    csv_reader = csv.reader(file)
    for row in csv_reader:
        print(row)

# 10. Write CSV file
data = [['John', 25], ['Jane', 30], ['Doe', 35]]
with open('output.csv', 'w', newline='') as file:
    csv_writer = csv.writer(file)
    csv_writer.writerows(data)

# 11. Read CSV using DictReader
with open('data.csv', 'r') as file:
    csv_reader = csv.DictReader(file)
    for row in csv_reader:
        print(row)

# 12. Write CSV using DictWriter
fieldnames = ['Name', 'Age']
data = [{'Name': 'John', 'Age': 25}, {'Name': 'Jane', 'Age': 30}, {'Name': 'Doe', 'Age': 35}]
with open('output.csv', 'w', newline='') as file:
    csv_writer = csv.DictWriter(file, fieldnames=fieldnames)
    csv_writer.writeheader()
    csv_writer.writerows(data)

# JSON

# 13. Read JSON from string
json_string = '{"name": "John", "age": 30}'
data = json.loads(json_string)
print(data)

# 14. Convert Python object to JSON string
data = {"name": "John", "age": 30}
json_string = json.dumps(data)
print(json_string)

# Pandas

# 15. Create DataFrame from dictionary
data = {'Name': ['John', 'Jane', 'Doe'], 'Age': [25, 30, 35]}
df = pd.DataFrame(data)
print(df)

# 16. Convert DataFrame to dictionary
data = df.to_dict()
print(data)

# CSV

# 17. Read CSV into dictionary
with open('data.csv', 'r') as file:
    csv_reader = csv.DictReader(file)
    data = [row for row in csv_reader]
    print(data)

# 18. Write dictionary to CSV
fieldnames = ['Name', 'Age']
data = [{'Name': 'John', 'Age': 25}, {'Name': 'Jane', 'Age': 30}, {'Name': 'Doe', 'Age': 35}]
with open('output.csv', 'w', newline='') as file:
    csv_writer = csv.DictWriter(file, fieldnames=fieldnames)
    csv_writer.writeheader()
    csv_writer.writerows(data)

# 19. Read specific columns from CSV into DataFrame
df = pd.read_csv('data.csv', usecols=['Name', 'Age'])
print(df)

# 20. Write specific columns from DataFrame to CSV
df.to_csv('output.csv', columns=['Name', 'Age'], index=False)