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Pandas: Get topmost n records within each group of a DataFrame

Pandas: DataFrame Exercise-61 with Solution

Write a Pandas program to get topmost n records within each group of a DataFrame.

Sample Solution :

Python Code :

import pandas as pd
d = {'col1': [1, 2, 3, 4, 7, 11], 'col2': [4, 5, 6, 9, 5, 0], 'col3': [7, 5, 8, 12, 1,11]}
df = pd.DataFrame(data=d)
print("Original DataFrame")
print(df)
print("\ntopmost n records within each group of a DataFrame:")
df1 = df.nlargest(3, 'col1')
print(df1)
df2 = df.nlargest(3, 'col2')
print(df2)
df3 = df.nlargest(3, 'col3')
print(df3)

Sample Output:

Original DataFrame
   col1  col2  col3
0     1     4     7
1     2     5     5
2     3     6     8
3     4     9    12
4     7     5     1
5    11     0    11

topmost n records within each group of a DataFrame:
   col1  col2  col3
5    11     0    11
4     7     5     1
3     4     9    12
   col1  col2  col3
3     4     9    12
2     3     6     8
1     2     5     5
4     7     5     1
   col1  col2  col3
3     4     9    12
5    11     0    11
2     3     6     8

Python Code Editor:


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Python: Tips of the Day

Creates a dictionary with the same keys as the provided dictionary and values generated by running the provided function for each value

Example:

def tips_map_values(obj, fn):
  ret = {}
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  return ret
users = {
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Output:

{'Owen': 29, 'Eddie': 15}