Python 如何移动第二个x轴的位置？

我正在尝试创建一个带有辅助x轴的图形，但是我希望辅助x轴的标签和记号位于第一个x轴之下。我目前只找到了将其移动到底部的方法，而没有找到精确的位置。我附上了一张我正在努力实现的图像

y = [3, 5, 2, 8, 7]
x = [[10, 11, 12, 13, 14], [36, 39.6, 43.2, 46.8, 50.4]]
labels = ['m/s', 'km/hr']

fig,ax = plt.subplots()
ax.plot(x[0], y)
ax.set_xlabel("Velocity m/s")
ax.set_ylabel("Time /mins")

ax2=ax.twiny()
ax2.plot(x[1], y)
ax2.set_xlabel("Velocity km/hr")
plt.show()

答案 首先，您必须包括所需的库：

import matplotlib.pyplot as plt
from mpl_toolkits.axes_grid1 import host_subplot
import mpl_toolkits.axisartist as AA

然后，您可以使用

ax = host_subplot(111, axes_class = AA.Axes, figure = fig)

然后通过以下步骤生成次轴：

ax2=ax.twiny()

此时需要为次轴留出一些空间，因此应使用

plt.subplots_adjust(bottom = 0.2)

最后将次轴定位在第一个轴下方

offset = -40
new_fixed_axis = ax2.get_grid_helper().new_fixed_axis
ax2.axis['bottom'] = new_fixed_axis(loc = 'bottom',
                                    axes = ax2,
                                    offset = (0, offset))
ax2.axis['bottom'].toggle(all = True)

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全部代码

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结果

import matplotlib.pyplot as plt
from mpl_toolkits.axes_grid1 import host_subplot
import mpl_toolkits.axisartist as AA

y = [3, 5, 2, 8, 7]
x = [[10, 11, 12, 13, 14], [36, 39.6, 43.2, 46.8, 50.4]]
labels = ['m/s', 'km/hr']

fig = plt.figure()
# generate the first axis
ax = host_subplot(111, axes_class = AA.Axes, figure = fig)
ax.plot(x[0], y)
ax.set_xlabel("Velocity m/s")
ax.set_ylabel("Time /mins")

ax2=ax.twiny()

# make space for the secondary axis
plt.subplots_adjust(bottom = 0.2)

# set position ax2 axis
offset = -40
new_fixed_axis = ax2.get_grid_helper().new_fixed_axis
ax2.axis['bottom'] = new_fixed_axis(loc = 'bottom',
                                    axes = ax2,
                                    offset = (0, offset))
ax2.axis['bottom'].toggle(all = True)

ax2.plot(x[1], y)
ax2.set_xlabel("Velocity km/hr")
plt.show()