I have a pandas dataframe that looks like this
ID country month revenue profit ebit
234 USA 201409 10 5 3
344 USA 201409 9 7 2
532 UK 201410 20 10 5
129 Canada 201411 15 10 5
I want to group by ID, country, month and count the IDs per month and country and sum the revenue, profit, ebit.
The output for the above data would be:
country month revenue profit ebit count
USA 201409 19 12 5 2
UK 201409 20 10 5 1
Canada 201411 15 10 5 1
I have tried different variations of groupby, sum and count functions of pandas but I am unable to figure out how to apply groupby sum and count all together to give the result as shown. Please share any ideas that you might have. Thanks!
It can be done using pivot_table this way:
>>> df1=pd.pivot_table(df, index=['country','month'],values=['revenue','profit','ebit'],aggfunc=np.sum)
>>> df1
ebit profit revenue
country month
Canada 201411 5 10 15
UK 201410 5 10 20
USA 201409 5 12 19
>>> df2=pd.pivot_table(df, index=['country','month'], values='ID',aggfunc=len).rename('count')
>>> df2
country month
Canada 201411 1
UK 201410 1
USA 201409 2
>>> pd.concat([df1,df2],axis=1)
ebit profit revenue count
country month
Canada 201411 5 10 15 1
UK 201410 5 10 20 1
USA 201409 5 12 19 2
You can do the groupby, and then map the counts of each country to a new column.
g = df.groupby(['country', 'month'])['revenue', 'profit', 'ebit'].sum().reset_index()
g['count'] = g['country'].map(df['country'].value_counts())
g
Out[3]:
country month revenue profit ebit count
0 Canada 201411 15 10 5 1
1 UK 201410 20 10 5 1
2 USA 201409 19 12 5 2
Edit
To get the counts per country and month, you can do another groupby, and then join the two DataFrames together.
g = df.groupby(['country', 'month'])['revenue', 'profit', 'ebit'].sum()
j = df.groupby(['country', 'month']).size().to_frame('count')
pd.merge(g, j, left_index=True, right_index=True).reset_index()
Out[6]:
country month revenue profit ebit count
0 Canada 201411 15 10 5 1
1 UK 201410 20 10 5 1
2 UK 201411 10 5 2 1
3 USA 201409 19 12 5 2
I added another record for the UK with a different date - notice how there are now two UK entries in the merged DataFrame, with the appropriate counts.
