Plotting Pandas Multiindex Bar Chart

import pandas as pd

data = pd.DataFrame([
        ('Q1','Blue',100),
        ('Q1','Green',300),
        ('Q2','Blue',200),
        ('Q2','Green',350),
        ('Q3','Blue',300),
        ('Q3','Green',400),
        ('Q4','Blue',400),
        ('Q4','Green',450),
    ], 
    columns=['quarter', 'company', 'value']
)
data = data.set_index(['quarter', 'company']).value

data.unstack().plot(kind='bar', stacked=True)

If you don’t want to stack your bar chart:

data.unstack().plot(kind='bar')