Please note, this is a STATIC archive of website www.w3resource.com from 19 Jul 2022, cach3.com does not collect or store any user information, there is no "phishing" involved.
w3resource

Pandas: Split the specified dataframe into groups based on all columns and calculate Groupby value counts on the dataframe

Pandas Grouping and Aggregating: Split-Apply-Combine Exercise-14 with Solution

Write a Pandas program to split the following dataframe into groups based on all columns and calculate GroupBy value counts on the dataframe.

Test Data:

   id  type     book
0   1    10     Math
1   2    15  English
2   1    11  Physics
3   1    20     Math
4   2    21  English
5   1    12  Physics
6   2    14  English

Sample Solution:

Python Code :

import pandas as pd
df = pd.DataFrame( {'id' : [1, 2, 1, 1, 2, 1, 2], 
                    'type' : [10, 15, 11, 20, 21, 12, 14], 
                    'book' : ['Math','English','Physics','Math','English','Physics','English']})

print("Original DataFrame:")
print(df)
result = df.groupby(['id', 'type', 'book']).size().unstack(fill_value=0)
print("\nResult:")
print(result)

Sample Output:

Original DataFrame:
   id  type     book
0   1    10     Math
1   2    15  English
2   1    11  Physics
3   1    20     Math
4   2    21  English
5   1    12  Physics
6   2    14  English

Result:
book     English  Math  Physics
id type                        
1  10          0     1        0
   11          0     0        1
   12          0     0        1
   20          0     1        0
2  14          1     0        0
   15          1     0        0
   21          1     0        0

Python Code Editor:


Have another way to solve this solution? Contribute your code (and comments) through Disqus.

Previous: Write a Pandas program to split the following dataframe into groups based on first column and set other column values into a list of values.
Next: Write a Pandas program to split the following dataframe into groups and count unique values of ‘value’ column.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.



Python: Tips of the Day

Find current directory and file's directory:

To get the full path to the directory a Python file is contained in, write this in that file:

import os 
dir_path = os.path.dirname(os.path.realpath(__file__))

(Note that the incantation above won't work if you've already used os.chdir() to change your current working directory, since the value of the __file__ constant is relative to the current working directory and is not changed by an os.chdir() call.)

To get the current working directory use

import os
cwd = os.getcwd()

Documentation references for the modules, constants and functions used above:

  • The os and os.path modules.
  • The __file__ constant
  • os.path.realpath(path) (returns "the canonical path of the specified filename, eliminating any symbolic links encountered in the path")
  • os.path.dirname(path) (returns "the directory name of pathname path")
  • os.getcwd() (returns "a string representing the current working directory")
  • os.chdir(path) ("change the current working directory to path")

Ref: https://bit.ly/3fy0R6m