Seaborn FacetGrid 图例在更改线宽时丢失线型细节

Question

如果我通过 FacetGrid().map() 更改 plt.plot 实例的线宽，我会丢失图例中线型的详细信息。在此图中，线型在图表

中是正确可见的

但是，如果我增加线宽 z 不再正确显示线型

如果你想重现图表，这里是代码，

import numpy as np
import seaborn as sbn
import pandas as pd
import matplotlib.pyplot as plt
x = np.tile(np.linspace(0,10,11),2)
y = np.linspace(1,11,11)
z = np.linspace(2,12,11)
yz = np.append(y,z)
y_or_z = np.repeat(['y','z'],11)
df = pd.DataFrame(data={'x':x,'yz':yz,'y_or_z':y_or_z})
g=sbn.FacetGrid(data = df, size=4, aspect=1.2, hue = 'y_or_z', hue_kws=dict(ls=['-','-.']))
g.map(plt.plot,'x','yz', lw=4).add_legend()
g.savefig('ex1')
g=sbn.FacetGrid(data = df, size=4, aspect=1.2, hue = 'y_or_z', hue_kws=dict(ls=['-','-.']))
g.map(plt.plot,'x','yz').add_legend()
g.savefig('ex2')

Answer 1

您可能会注意到第二个图中的橙色线比蓝色线短。因此图例确实显示了正确的线条样式，但图例手柄的长度不足以容纳完整的线条样式。

您当然可以更改手柄长度，使其适合完整的线型循环，例如

g.add_legend(handlelength=10)

handlelength 参数记录在 matplotlib legend documentation:

handlelength : float or None
The length of the legend handles. Measured in font-size units. Default is None which will take the value from the legend.handlelength rcParam.

Seaborn FacetGrid 图例在更改线宽时丢失线型细节

Seaborn FacetGrid legend loses linestyle details when changing linewidth

python

matplotlib

plot

seaborn

facet-grid