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计算:Ax-b
A: 2*2
x: 2*1
b: 2*1
so, Ax-b: 2*1
if __name__ == "__main__": A = np.array([[4.0, 1.0], [1.0, 3.0]]) b = np.array([[1.0], [2.0]]) x_0 = np.array([[2.0], [1.0]]) r_k = A * x_0 - b print(r_k)
错误!!!
修改:
if __name__ == "__main__": A= mat([[4.0, 1.0], [1.0, 3.0]]) b = mat([[1.0], [2.0]]) x_0 = mat([[2.0], [1.0]]) r_k = A * x_0 - b print(r_k)
if __name__ == "__main__": A= mat([[4.0, 1.0], [1.0, 3.0]]) b = mat([[1.0], [2.0]]) x_k = mat([[2.0], [1.0]]) p_k = -x_k # 2行1列 r_k = A * x_k - b # 2行1列 alpha_k = (np.transpose(r_k) * r_k) / (np.transpose(p_k) * A * p_k) # 1行1列 ----------------------------------------------- x_k = x_k + alpha_k * p_k #2行1列 !!!!这里报错 ----------------------------------------------- print(x_k)
修改:
if __name__ == "__main__": A= mat([[4.0, 1.0], [1.0, 3.0]]) b = mat([[1.0], [2.0]]) x_k = mat([[2.0], [1.0]]) p_k = -x_k # 2*1 r_k = A * x_k - b # 2*1 alpha_k = (np.transpose(r_k) * r_k) / (np.transpose(p_k) * A * p_k) # 1*1 ----------------------------------------------- x_k = x_k + p_k *alpha_k ----------------------------------------------- print(x_k)
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