如何在其中一个图上具有一个共享的X轴和多个Y轴的堆叠图？

Question

I am trying to modify this example so also have a second plot on top sharing the same X-axis. Unfortunately, it is not clear how to add subplots to this structure. I have tried to directly combine a different example, but it just creates two figures.

How do I put another plot separated from the two-y-axis plot with the same X-axis?

"""
Parasite axis demo

The following code is an example of a parasite axis. It aims to show a user how
to plot multiple different values onto one single plot. Notice how in this
example, par1 and par2 are both calling twinx meaning both are tied directly to
the x-axis. From there, each of those two axis can behave separately from the
each other, meaning they can take on separate values from themselves as well as
the x-axis.
"""
from mpl_toolkits.axes_grid1 import host_subplot
import mpl_toolkits.axisartist as AA
import matplotlib.pyplot as plt

host = host_subplot(111, axes_class=AA.Axes)
plt.subplots_adjust(right=0.75)

par1 = host.twinx()
par2 = host.twinx()

offset = 60
new_fixed_axis = par2.get_grid_helper().new_fixed_axis
par2.axis["right"] = new_fixed_axis(loc="right",
                                    axes=par2,
                                    offset=(offset, 0))

par2.axis["right"].toggle(all=True)

host.set_xlim(0, 2)
host.set_ylim(0, 2)

host.set_xlabel("Distance")
host.set_ylabel("Density")
par1.set_ylabel("Temperature")
par2.set_ylabel("Velocity")

p1, = host.plot([0, 1, 2], [0, 1, 2], label="Density")
p2, = par1.plot([0, 1, 2], [0, 3, 2], label="Temperature")
p3, = par2.plot([0, 1, 2], [50, 30, 15], label="Velocity")

par1.set_ylim(0, 4)
par2.set_ylim(1, 65)

host.legend()

host.axis["left"].label.set_color(p1.get_color())
par1.axis["right"].label.set_color(p2.get_color())
par2.axis["right"].label.set_color(p3.get_color())

## Attempts to add stacked plot on top
f, axarr = plt.subplots(2, sharex=True)
axarr[1].plot([0,1,2], [5,6,7])
axarr[1].set_title('Sharing X axis')

plt.draw()
plt.show()

Answer 1

You can create a new host subplot and share the xaxis.

replace host = host_subplot(111, axes_class=AA.Axes) with host = host_subplot(211, axes_class=AA.Axes)

replace the lines below your line ## Attempts to add stacked plot on top with

host2 = host_subplot(212, axes_class=AA.Axes, sharex=host)
host2.plot([0,1,2], [5,6,7])
host2.set_title('Sharing X axis')
plt.tight_layout()
plt.draw()
plt.show()

this results in