Class 12 Informatics Practices Worksheet: DataFrame Attributes

Class 12 Informatics Practices Worksheet: DataFrame Attributes

Part A: Fill in the Blanks

1. The attribute used to get the number of rows in a DataFrame is __________.
2. To get the column names of a DataFrame, use the __________ attribute.
3. The __________ attribute returns the index of a DataFrame.
4. To access the data types of each column in a DataFrame, use the __________ attribute.
5. The attribute that returns the number of elements in a DataFrame is __________.

Part B: True or False

1. The df.shape attribute returns a tuple representing the number of rows and columns. (True / False)
2. The df.columns attribute provides the list of row indices in a DataFrame. (True / False)
3. The df.index attribute provides the index labels of a DataFrame. (True / False)
4. The df.dtypes attribute gives the data types of the DataFrame’s columns. (True / False)
5. The df.size attribute returns the total number of elements in the DataFrame. (True / False)

Part C: Short Answer Questions

1. What does the df.shape attribute represent? Provide an example.
2. How can you retrieve the names of all columns in a DataFrame using attributes? Write the code.
3. Explain the difference between df.index and df.columns.
4. How can you find out the data type of each column in a DataFrame? Provide an example.
5. Write the code to get the total number of elements in a DataFrame named df.

Part D: Practical Exercises

1. Given the following DataFrame:

   
   import pandas as pd
   
   data = {
       'Name': ['Alice', 'Bob', 'Charlie'],
       'Age': [24, 27, 22],
       'City': ['New York', 'Los Angeles', 'Chicago']
   }
   
   df = pd.DataFrame(data)
   

   Perform the following tasks:

   • Print the number of rows and columns using df.shape.
   • Retrieve and print the column names using df.columns.
   • Get and print the index labels using df.index.
   • Find and print the data types of each column using df.dtypes.
   • Determine and print the total number of elements using df.size.

2. Create a DataFrame with the following data:

   Product	Price	Stock
   A	100	50
   B	150	30
   C	200	20

   Write the code to:

   • Access and print the columns attribute.
   • Access and print the index attribute.
   • Access and print the dtypes attribute.
   • Print the shape attribute.

3. Given the DataFrame df:

   import pandas as pd
   
   data = {
       'Employee': ['John', 'Jane', 'Tom', 'Lucy'],
       'Salary': [50000, 55000, 60000, 65000],
       'Department': ['HR', 'Finance', 'IT', 'Admin']
   }
   
   df = pd.DataFrame(data)
   

   Write the code to:

   • Print the number of rows and columns.
   • Print the data type of the Salary column.
   • Print the total number of elements in the DataFrame.

Part E: Code Correction

Examine the following code snippets and correct any mistakes related to DataFrame attributes. Rewrite the correct code.

1. 
   import pandas as pd
   
   data = {
       'Name': ['Anna', 'Ben', 'Charlie'],
       'Age': [22, 23, 25]
   }
   
   df = pd.DataFrame(data)
   print(df.shape)  # Correct
   print(df.columns)  # Correct
   print(df.index())  # Incorrect
   

2. 
   import pandas as pd
   
   data = {
       'Product': ['X', 'Y', 'Z'],
       'Price': [10, 20, 30]
   }
   
   df = pd.DataFrame(data)
   print(df.dtypes)  # Correct
   print(df.size)  # Correct
   print(df.columns())  # Incorrect