﻿ Pandas DataFrame: Convert index in a column of the given dataframe - w3resource

# Pandas DataFrame: Convert index in a column of the given dataframe

## Pandas: DataFrame Exercise-33 with Solution

Write a Pandas program to convert index in a column of the given dataframe.

Sample data:
Original DataFrame
attempts name qualify score
0 1 Anastasia yes 12.5
1 3 Dima no 9.0
2 2 Katherine yes 16.5
3 3 James no NaN
4 2 Emily no 9.0
5 3 Michael yes 20.0
6 1 Matthew yes 14.5
7 1 Laura no NaN
8 2 Kevin no 8.0
9 1 Jonas yes 19.0
After converting index in a column:
index attempts name qualify score
0 0 1 Anastasia yes 12.5
1 1 3 Dima no 9.0
2 2 2 Katherine yes 16.5
3 3 3 James no NaN
4 4 2 Emily no 9.0
5 5 3 Michael yes 20.0
6 6 1 Matthew yes 14.5
7 7 1 Laura no NaN
8 8 2 Kevin no 8.0
9 9 1 Jonas yes 19.0
Hiding index:
index attempts name qualify score
0 1 Anastasia yes 12.5
1 3 Dima no 9.0
2 2 Katherine yes 16.5
3 3 James no NaN
4 2 Emily no 9.0
5 3 Michael yes 20.0
6 1 Matthew yes 14.5
7 1 Laura no NaN
8 2 Kevin no 8.0
9 1 Jonas yes 19.0

Sample Solution :

Python Code :

``````import pandas as pd
import numpy as np
exam_data = {'name': ['Anastasia', 'Dima', 'Katherine', 'James', 'Emily', 'Michael', 'Matthew', 'Laura', 'Kevin', 'Jonas'],
'score': [12.5, 9, 16.5, np.nan, 9, 20, 14.5, np.nan, 8, 19],
'attempts': [1, 3, 2, 3, 2, 3, 1, 1, 2, 1],
'qualify': ['yes', 'no', 'yes', 'no', 'no', 'yes', 'yes', 'no', 'no', 'yes']}
df = pd.DataFrame(exam_data)
print("Original DataFrame")
print(df)
print("\nAfter converting index in a column:")
df.reset_index(level=0, inplace=True)
print(df)
print("\nHiding index:")
print( df.to_string(index=False))
``````

Sample Output:

```  Original DataFrame
attempts       name qualify  score
0         1  Anastasia     yes   12.5
1         3       Dima      no    9.0
2         2  Katherine     yes   16.5
3         3      James      no    NaN
4         2      Emily      no    9.0
5         3    Michael     yes   20.0
6         1    Matthew     yes   14.5
7         1      Laura      no    NaN
8         2      Kevin      no    8.0
9         1      Jonas     yes   19.0

After converting index in a column:
index  attempts       name qualify  score
0      0         1  Anastasia     yes   12.5
1      1         3       Dima      no    9.0
2      2         2  Katherine     yes   16.5
3      3         3      James      no    NaN
4      4         2      Emily      no    9.0
5      5         3    Michael     yes   20.0
6      6         1    Matthew     yes   14.5
7      7         1      Laura      no    NaN
8      8         2      Kevin      no    8.0
9      9         1      Jonas     yes   19.0

Hiding index:
index  attempts       name qualify  score
0         1  Anastasia     yes   12.5
1         3       Dima      no    9.0
2         2  Katherine     yes   16.5
3         3      James      no    NaN
4         2      Emily      no    9.0
5         3    Michael     yes   20.0
6         1    Matthew     yes   14.5
7         1      Laura      no    NaN
8         2      Kevin      no    8.0
9         1      Jonas     yes   19.0
```

Python-Pandas Code Editor:

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## Python: Tips of the Day

Inserting if statements using conditional list comprehensions:

```x = [1, 2, 3, 4, 5, 6]
result = []
for idx in range(len(x)):
if x[idx] % 2 == 0:
result.append(x[idx] * 2)
else:
result.append(x[idx])
result
```

Output:

```[1, 4, 3, 8, 5, 12]
```
`[(element * 2 if element % 2 == 0 else element) for element in x]`

Output:

```[1, 4, 3, 8, 5, 12]
```
`[element * 2 for element in x if element % 2 == 0]`

Output:

```[4, 8, 12]
```