python matplotlib用面积填充实现lmplot的代码示例

import numpy as np
import matplotlib.pyplot as plt
x = np.arange(0, 2, 0.01)
y = np.sin(2 * np.pi * x)
plt.plot(x, y, color='black')
plt.fill_between(x, y)
plt.grid()
plt.show()

fill_between(x, y1, y2=0, where=None, interpolate=False, step=None, *,**kwargs)

plt.plot(x, y, color='black')
plt.fill_between(x, y, where=y > 0, facecolor='green', alpha=.5)
plt.fill_between(x, y, where=y < 0, facecolor='red', alpha=.5)
plt.show()

x = np.arange(0, 2, 0.02)
err = np.random.rand(100)/2
y = 2*x + 1 + err
# 构造并调用最小二乘法
A = np.array([x, np.ones_like(x)]).T
kb, res, _, _ = np.linalg.lstsq(A, y)

Y = kb[0]*x + kb[1]
dx = (x-x.mean())**2
E = x.std() * np.sqrt(1/len(x) + dx / np.sum(dx))
plt.scatter(x, y, marker='.')   # 原始数据
plt.plot(x, Y)                  # 趋势线
plt.fill_between(x, Y - E, Y + E, alpha=0.5)
plt.show()