26 lines
587 B
Python
26 lines
587 B
Python
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import numpy as np
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import matplotlib.pyplot as plt
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# 转化矩阵
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x = np.linspace(0, 10, 30).reshape(-1, 1)
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# 斜率和截距 随机生成
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w = np.random.randint(1, 5, 1)
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b = np.random.randint(1, 10, 1)
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# 根据一元一次方程计算目标值 y , 并加上 噪声, 数据上下有波动
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y = x * w + b + np.random.randn(30, 1)
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plt.scatter(x, y)
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# 重构 x, b 截距
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x = np.column_stack([x, np.full((30, 1), 1)])
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# 正规方程求解
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a = np.linalg.inv(x.T.dot(x)).dot(x.T).dot(y).round(2)
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print(w, b)
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print(a)
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# 输出回归线性图
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plt.plot(x[:, 0], x.dot(a), 'green')
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plt.show()
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