当我在同一张图上绘制两条曲线时，我很难设置X轴特定的极限。
我的数据有两条曲线（渗透性和孔隙度），深度将像索引一样工作。因此，我设法将它们绘制在同一张图上，并在一些帮助下填充了它们之间的区域。这是我的代码：
df = pd.DataFrame({'DEPTH': [100, 150, 200, 250, 300, 350, 400, 450, 500, 550],
'PERMEABILITY': [1000, 800, 900, 600, 200, 250, 400, 300, 100, 200],
'POROSITY': [0.30, 0.25, 0.15, 0.19, 0.15, 0.10, 0.15, 0.19, 0.10, 0.15]})
f, ax1 = plt.subplots()
ax1.set_xlabel('PERMEABILITY')
ax1.set_ylabel('DEPTH')
ax1.set_ylim(df['DEPTH'].max(), df['DEPTH'].min())
ax1.plot(df['PERMEABILITY'], df['DEPTH'], color='red')
ax1.tick_params(axis='x', labelcolor='red')
ax2 = ax1.twiny()
ax2.set_xlabel('POROSITY')
ax2.plot(df['POROSITY'], df['DEPTH'], color='blue')
ax2.tick_params(axis='x', labelcolor='blue')
# convert POROSITY axis to PERMEABILITY
# value-min / range -> normalized POROSITY (normp)
# normp*newrange + newmin -> stretched POROSITY to PERMEABILITY
z=df['POROSITY']
x=df['PERMEABILITY']
nz=((z-np.min(z))/(np.max(z)-np.min(z)))*(np.max(x)-np.min(x))+np.min(x)
# fill between in green where PERMEABILITY is larger
ax1.fill_betweenx(df['DEPTH'],x,nz,where=x>=nz,interpolate=True,color='g')
# fill between in yellow where POROSITY is larger
ax1.fill_betweenx(df['DEPTH'],x,nz,where=x<=nz,interpolate=True,color='y')
plt.show()
但是，当我尝试为X轴设置特定限制时，如下面的左图所示，此填充区域未遵循新的“曲线大小”。我的结果应该像右边的图像一样（我在Paint上做了这个）。例如，如果我添加：
ax1.set_xlim(0, 1500)
ax2.set_xlim(-0.10, 0.45)
有人可以帮助我吗？提前致谢！
Your calculation of
nzconverts between the two x axis scales. When you change the two scales by different amounts, you have to change your calculation ofnz. You'll need to work out how to do that precisely, but here I just eyeballed the slope and offset until it matched.另外，如果您在代码段中包含所有必需的导入，则更容易回答您的问题。