Legend not showing when plotting multiple seaborn plots

问题

I typically don't have problems with matplotlib legend, but this is the first time I am using it with multiple seaborn plots, and the following does not work.

fig = plt.figure(figsize=(10,6))
a =sns.regplot(x='VarX', y='VarY1', data=data)
b = sns.regplot(x='VarX', y='VarY2', data=data)
c = sns.regplot(x='VarX', y='VarY3', data=data)
fig.legend(handles=[a, b, c],labels=['First','Second','Third'])
fig.show()

What am I doing wrong?

回答1:

seaborn.regplot returns an axes. You cannot create a legend proxy handle from an axes. However this is not even necessary. Remove the handles from the legend and it should give the desired plot.

import matplotlib.pyplot as plt
import numpy as np; np.random.seed(1)
import pandas as pd
import seaborn as sns

data=pd.DataFrame({"VarX" : np.arange(10), 
                   'VarY1': np.random.rand(10),
                   'VarY2': np.random.rand(10),
                   'VarY3': np.random.rand(10)})

fig = plt.figure(figsize=(10,6))
sns.regplot(x='VarX', y='VarY1', data=data)
sns.regplot(x='VarX', y='VarY2', data=data)
sns.regplot(x='VarX', y='VarY3', data=data)
fig.legend(labels=['First','Second','Third'])
plt.show()

来源：https://stackoverflow.com/questions/48743867/legend-not-showing-when-plotting-multiple-seaborn-plots