| 201 |
Which accessor selects rows and columns by their position numbers? |
Computer Science/Informatics Practices
Indexing, merging and CSV |
Easy |
| 202 |
Which method writes a DataFrame df to a file named result.csv? |
Computer Science/Informatics Practices
Indexing, merging and CSV |
Easy |
| 203 |
A DataFrame has index r1 to r4 and Marks 78, 45, 91 and 62. How many rows does df[df['Marks'] > 60] return? |
Computer Science/Informatics Practices
Indexing, merging and CSV |
Medium |
| 204 |
For the same DataFrame with index r1, r2, r3, r4, which two expressions both return the rows r2 and r3? |
Computer Science/Informatics Practices
Indexing, merging and CSV |
Medium |
| 205 |
d1 has id values 1, 2, 3 and d2 has id values 2, 3, 4, each with one other column. How many rows does pd.merg… |
Computer Science/Informatics Practices
Indexing, merging and CSV |
Hard |
| 206 |
Which function returns the number of non-missing values in each column of a DataFrame? |
Computer Science/Informatics Practices
Descriptive statistics |
Easy |
| 207 |
Which Pandas method gives count, mean, standard deviation, minimum, quartiles and maximum together? |
Computer Science/Informatics Practices
Descriptive statistics |
Easy |
| 208 |
For s = pd.Series([2, 4, 4, 4, 5, 5, 7, 9]), what is s.median()? |
Computer Science/Informatics Practices
Descriptive statistics |
Medium |
| 209 |
For u = pd.Series([10, np.nan, 30, 40]), what does u.mean() return? |
Computer Science/Informatics Practices
Descriptive statistics |
Medium |
| 210 |
df = pd.DataFrame({'P': [3, 1], 'Q': [4, 2]}). What does df.max(axis=1) return? |
Computer Science/Informatics Practices
Descriptive statistics |
Hard |
| 211 |
Which method arranges the rows of a DataFrame in order of the values of a column? |
Computer Science/Informatics Practices
Aggregation, grouping and pivoting |
Easy |
| 212 |
In df.groupby('Dept')['Sal'].sum(), what does groupby('Dept') do? |
Computer Science/Informatics Practices
Aggregation, grouping and pivoting |
Easy |
| 213 |
Dept values are HR, IT, HR, IT, Sales with salaries 30, 50, 40, 60, 20. What does df.groupby('Dept')['Sal'].s… |
Computer Science/Informatics Practices
Aggregation, grouping and pivoting |
Medium |
| 214 |
s = pd.Series([1, 2, 3], index=['a', 'b', 'c']). What does s.reindex(['c', 'a', 'z']) contain? |
Computer Science/Informatics Practices
Aggregation, grouping and pivoting |
Medium |
| 215 |
A sales table has columns Year, Item and Qty, and the pair (2020, Pen) appears twice. Which method can reshap… |
Computer Science/Informatics Practices
Aggregation, grouping and pivoting |
Hard |
| 216 |
What does NaN represent in a Pandas DataFrame? |
Computer Science/Informatics Practices
Missing values and MySQL |
Easy |
| 217 |
Which method replaces all missing values in df with 0? |
Computer Science/Informatics Practices
Missing values and MySQL |
Easy |
| 218 |
df has columns A = [1, NaN, 3] and B = [NaN, NaN, 6]. What is the shape of df.dropna()? |
Computer Science/Informatics Practices
Missing values and MySQL |
Medium |
| 219 |
For the same df, what is the shape of df.dropna(how='all')? |
Computer Science/Informatics Practices
Missing values and MySQL |
Medium |
| 220 |
A student wants to add the rows of a DataFrame df to an existing MySQL table result without deleting old rows… |
Computer Science/Informatics Practices
Missing values and MySQL |
Hard |