Informatics Practices
Ekam, a Data Analyst with a multinational brand has designed the DataFrame df that contains the four quarter’s sales data of different stores as shown below :
| Store | Qtr1 | Qtr2 | Qtr3 | Qtr4 | |
|---|---|---|---|---|---|
| 0 | Store1 | 300 | 240 | 450 | 230 |
| 1 | Store2 | 350 | 340 | 403 | 210 |
| 2 | Store3 | 250 | 180 | 145 | 160 |
Answer the following questions :
(i) Predict the output of the following python statement :
(a) print(df.size)
(b) print(df[1:3])
(ii) Delete the last row from the DataFrame.
(iii) Write Python statement to add a new column Total_Sales which is the addition of all the 4 quarter sales.
Or (Option for part (iii) only)
Write Python statement to export the DataFrame to a CSV file named data.csv stored at D: drive.
Answer
(i)
(a) print(df.size)
Output
15
Explanation
The size attribute of a DataFrame returns the total number of elements in the DataFrame df.
(b) print(df[1:3])
Output
Store Qtr1 Qtr2 Qtr3 Qtr4
1 Store2 350 340 403 210
2 Store3 250 180 145 160
Explanation
This statement uses slicing to extract rows 1 and 2 from the DataFrame df.
(ii)
df = df.drop(2)
Output
Store Qtr1 Qtr2 Qtr3 Qtr4
0 Store1 300 240 450 230
1 Store2 350 340 403 210
(iii)
df['Total_Sales'] = df['Qtr1'] + df['Qtr2'] + df['Qtr3'] + df['Qtr4']
Output
Store Qtr1 Qtr2 Qtr3 Qtr4 Total_Sales
0 Store1 300 240 450 230 1220
1 Store2 350 340 403 210 1303
2 Store3 250 180 145 160 735
Or
DataFrame.to_csv('D:\\data.csv')
Related Questions
Consider the given DataFrame 'Genre' :
No Type Code 0 Fiction F 1 Non-fiction NF 2 Drama D 3 Poetry P Write suitable Python statements for the following :
(i) Add a column called Num_Copies with the following data : [300, 290, 450, 760].
(ii) Add a new genre of type 'Folk Tale' having code as "FT" and 600 number of copies.
(iii) Rename the column 'Code' to 'Book_Code'.
Preeti manages database in a blockchain start-up. For business purposes, she created a table named BLOCKCHAIN. Assist her by writing the following queries :
TABLE : BLOCKCHAIN
id user value hash transaction_date 1 Steve 900 ERTYU 2020-09-19 2 Meesha 145 @345r 2021-03-23 3 Nimisha 567 #wert5 2020-05-06 4 Pihu 678 %rtyu 2022-07-13 5 Kopal 768 rrt4% 2021-05-15 7 Palakshi 534 wer@3 2022-11-29 (i) Write a query to display the year of oldest transaction.
(ii) Write a query to display the month of most recent transaction.
(iii) Write a query to display all the transactions done in the month of May.
(iv) Write a query to count total number of transactions in the year 2022.
Write suitable SQL queries for the following :
(i) To calculate the exponent for 3 raised to the power of 4.
(ii) To display current date and time.
(iii) To round off the value -34.4567 to 2 decimal place.
(iv) To remove all the probable leading and trailing spaces from the column userid of the table named user.
(v) To display the length of the string ‘FIFA World Cup’.
Kabir has created the following table named exam :
RegNo Name Subject Marks 1 Sanya Computer Science 198 2 Sanchay IP 100 3 Vinesh CS 90 4 Sneha IP 99 5 Akshita IP 100 Help him in writing SQL queries to perform the following tasks :
(i) Insert a new record in the table having following values : [6, 'Khushi', 'CS', 85]
(ii) To change the value "IP" to "Informatics Practices" in Subject column.
(iii) To remove the records of those students whose marks are less than 30.
(iv) To add a new column Grade of suitable datatype.
(v) To display records of "Informatics Practices" subject.