我想创建一个带有两个 y 轴和交互式图例的图。我根据以下内容制作了一个最小的“工作”示例：https ://matplotlib.org/3.1.1/gallery/event_handling/legend_picking.html
import matplotlib.pyplot as plt
import numpy as np
t = np.arange(0.0, 5, 0.01)
y1 = 2*np.sin(2*np.pi*t)
y2 = 4*np.sin(2*np.pi*2*t)+1
fig, ax = plt.subplots()
ax.set_title('Click on legend line to toggle line on/off')
line1, = ax.plot(t, y1, lw=2, label='1 HZ')
ax2 = ax.twinx()
line2, = ax2.plot(t, y2, lw=2, label='2 HZ')
lines_twinx=[line1,line2]
lbl = [l.get_label() for l in lines_twinx]
leg=ax.legend(lines_twinx, lbl, loc="upper left",fontsize='xx-small', shadow=True)
leg.get_frame().set_alpha(0.4)
lined = dict()
for legline, origline in zip(leg.get_lines(), lines_twinx):
legline.set_picker(5) # 5 pts tolerance
lined[legline] = origline
def onpick(event):
# on the pick event, find the orig line corresponding to the
# legend proxy line, and toggle the visibility
legline = event.artist
origline = lined[legline]
vis = not origline.get_visible()
origline.set_visible(vis)
# Change the alpha on the line in the legend so we can see what lines
# have been toggled
if vis:
legline.set_alpha(1.0)
else:
legline.set_alpha(0.2)
fig.canvas.draw()
fig.canvas.mpl_connect('pick_event', onpick)
plt.show()
不知何故，图例不可点击。有人知道该怎么做吗？
