pandas - lesson 06

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• Lesson 06

#!/usr/bin/env python
# coding: utf-8
 
# Lesson 6
 
# > Lets take a look at the ***groupby*** function.
 
# Import libraries
import pandas as pd
import sys
 
print('Python version ' + sys.version)
print('Pandas version ' + pd.__version__)
 
# Our small data set
d = {'one':[1,1,1,1,1],
     'two':[2,2,2,2,2],
     'letter':['a','a','b','b','c']}
 
# Create dataframe
df = pd.DataFrame(d)
df
 
# Create group object
one = df.groupby('letter')
 
# Apply sum function
one.sum()
 
letterone = df.groupby(['letter','one']).sum()
letterone
 
letterone.index
 
# You may want to ***not*** have the columns you are grouping by become your index, this can be easily achieved as shown below.
letterone = df.groupby(['letter','one'], as_index=False).sum()
letterone
 
letterone.index