import numpy as np
import matplotlib.pyplot as plt

# 数据
x = np.array([3.59, 2.2, 1.53, 1.07, 0.7])
y = np.array([-0.0011, -0.0011, -0.0010, -0.0010, -0.0015])

# 拟合多项式
coefficients = np.polyfit(x, y, 2)  # 二次多项式拟合
polynomial = np.poly1d(coefficients)

# 生成拟合曲线的x值
x_fit = np.linspace(min(x), max(x), 100)
y_fit = polynomial(x_fit)

# 绘制数据点和拟合曲线
plt.scatter(x, y, color='red', label='数据点')
plt.plot(x_fit, y_fit, label='拟合曲线')

# 添加标题和标签
plt.title('数据拟合')
plt.xlabel('X')
plt.ylabel('Y')
plt.legend()

# 保存图片
plt.savefig('pitch.png')
#打印拟合多项式
print(polynomial)