Legend only shows one label when plotting with pandas

Question

I have two Pandas DataFrames that I\'m hoping to plot in single figure. I\'m using IPython notebook.

I would like the legend to show the label for both of the DataFr

Answer 1

You can use pd.concat to merge the two dataframes and then plot is using a secondary y-axis:

import numpy as np  # For generating random data.
import pandas as pd

# Creating data.
np.random.seed(0)
prng = pd.period_range('1/1/2011', '1/1/2012', freq='M')
var = pd.DataFrame(np.random.randn(len(prng)), index=prng, columns=['total'])
shares = pd.DataFrame(np.random.randn(len(prng)), index=prng, columns=['average'])

# Plotting.
ax = (
    pd.concat([var, shares], axis=1)
    .rename(columns={
        'total': 'Variance of Low Wages',
        'average': 'Average Age'
    })
    .plot(
        title='Wage Variance and Mean Age',
        secondary_y='Average Age')
)
ax.set_ylabel('Variance of Low Wages')
ax.right_ax.set_ylabel('Average Age', rotation=-90)