Python散布図とmatplotlib

Question

私は、私がトレンドラインを描画したいと思っているPythonの散布図を持っています。代わりに、曲線であることの

import matplotlib.pyplot as plt 
import numpy as np 

x=np.array([9.80,13.20,13.46,14.09,13.96,10.77,8.79,8.61,8.83,11.08,10.13,12.40,9.90,10.96,12.75,11.79,11.79,12.38,12.78,13.08,12.83,12.57,12.96,12.90,12.91,13.67,12.83,12.50,12.42,12.83,12.82,12.70,12.60,12.90,13.20]) 
y=np.array([0.0706,0.0969,0.0997,0.1031,0.0848,0.1044,0.0815,0.1030,0.0783,0.0970,0.1193,0.0796,0.0697,0.0738,0.0895,0.0912,0.0887,0.0973,0.0942,0.1052,0.0984,0.0965,0.0903,0.0876,0.1071,0.0872,0.0857,0.0967,0.0926,0.0837,0.0967,0.0935,0.0946,0.0930,0.0758 
]) 

plt.scatter(x, y) 
fit = np.polyfit(x, y, deg=4) 
p = np.poly1d(fit) 
plt.plot(x,p(x),"r--") 
plt.show() 

しかし、結果ラインラインのちょうどミックスです：さまざまな例から私は私のコードは次のようにあるトレンドラインを描画する方法を学ぶためにインターネットを中心に発見しました。誰も私の間違いを説明できますか？

Answer 1

xの値はソートされていないためだと思います。このコードを見てください：

import matplotlib.pyplot as plt 
import numpy as np 

x=np.array([9.80,13.20,13.46,14.09,13.96,10.77,8.79,8.61,8.83,11.08,10.13,12.40,9.90,10.96,12.75,11.79,11.79,12.38,12.78, 
      13.08,12.83,12.57,12.96,12.90,12.91,13.67,12.83,12.50,12.42,12.83,12.82,12.70,12.60,12.90,13.20]) 

y=np.array([0.0706,0.0969,0.0997,0.1031,0.0848,0.1044,0.0815,0.1030,0.0783,0.0970,0.1193,0.0796,0.0697,0.0738, 
      0.0895,0.0912,0.0887,0.0973,0.0942,0.1052,0.0984,0.0965,0.0903,0.0876,0.1071,0.0872,0.0857,0.0967,0.0926,0.0837,0.0967,0.0935,0.0946,0.0930,0.0758 ]) 

# Here I sort x values and their corresponding y values 
args = np.argsort(x) 
x = x[args] 
y = y[args] 

plt.scatter(x, y) 
fit = np.polyfit(x, y, deg=4) 
p = np.poly1d(fit) 
plt.plot(x,p(x),"r--") 
plt.show() 

結果：これがどうなる

Answer 2

：

plt.scatter(x,y) 
x = sorted(x) 
plt.plot(x,p(x),"r--") 

をトリックはオーバーラインをプロットする前にx値をソートすることですそれら。