Percentage of Total with Groupby for two columns

Question

I have a DataFrame:

df = pd.DataFrame({
    'Product': ['AA', 'AA', 'AA', 'AA', 'BB', 'BB', 'BB', 'BB'],
    'Type': ['AC', 'AC', 'AD', 'AD', 'BC', 'BC', 'BD', 'BD'],
    'Sales': [ 200, 100, 400, 100, 300, 100, 200, 500], 
    'Qty': [ 5, 3, 3, 6, 4, 7, 4, 1]})

I want to try and get the percentage of total by "Product" and "Type" for both "Sales" and "Qty". I can get the percentage of total for "Sales" and "Qty" separately. But I was wondering if there was a way of doing so for both columns.

To get the percentage of total for one column, the code is:

df['Sales'] = df['Sales'].astype(float)
df['Qty'] = df['Qty'].astype(float)
df = df[['Product', 'Type', 'Sales']]

df = df.groupby(['Product', 'Type']).agg({'Sales': 'sum'})
pcts = df.groupby(level= [0]).apply(lambda x: 100 * x / float(x.sum()))

Is there a way of get this for both columns in one go?

Answer 1

You can chain groupby:

pct = lambda x: 100 * x / x.sum()

out = df.groupby(['Product', 'Type']).sum().groupby('Product').apply(pct)
print(out)

# Output
                  Sales        Qty
Product Type                      
AA      AC    37.500000  47.058824
        AD    62.500000  52.941176
BB      BC    36.363636  68.750000
        BD    63.636364  31.250000