Grouping

one or more of the following steps:

Splitting the data into groups based on some criteria
Applying a function to each group independently
Combining the results into a data structure



In [1]:

    
import pandas as pd
import numpy as np



In [2]:

    
file_name_string = 'C:/Users/Charles Kelly/Desktop/Exercise Files/02_07/Begin/EmployeesWithGrades.xlsx'
employees_df = pd.read_excel(file_name_string, 'Sheet1', index_col=None, na_values=['NA'])



In [ ]:

group by Department

documentation: http://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.groupby.html

calculate total years of service by employees in each department



In [4]:

    
employees_df.groupby('Department').sum()









    Out[4]:






  
    
      
      YearsOfService
    
    
      Department
      
    
  
  
    
      Accounting
      47
    
    
      Engineering
      60
    
    
      Marketing
      52



In [ ]: