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题解 | Gauss-Seidel法求解线性方程组（矩阵表示法）

import numpy as np def gauss_seidel(A, b, n, x_ini=None): x = x_ini or np.zeros_like(b) D = np.diag(np.diag(A)) #提取对角阵 L = -np.tril(A,k ...

2025-05-21

0 72

题解 | 计算相关矩阵

import numpy as np def cal_cov_matrix(X,Y): X_centered = X - X.mean(axis = 0) Y_centered = Y - Y.mean(axis = 0) return (X_centered.T @ Y_...

2025-05-20

0 67

题解 | 计算矩阵的积

def matrixmul(a,b): a_col = len(a[0]) a_row = len(a) b_col = len(b[0]) b_row = len(b) if a_col != b_row: return -1 els...

2025-05-20

0 44

题解 | 实现压缩列稀疏矩阵

def compressed_col_sparse_matrix(dense_matrix): vals = [] row_idx = [] cnt = [0 for _ in range(len(dense_matrix[0]) + 1)] col_ptr = [...

2025-05-16

0 51

题解 | 计算协方差矩阵

import numpy as np def calculate_covariance_matrix(vectors): # 补全代码 feature_num = len(vectors) sample_num = len(vectors[0]) cov_matr...

2025-05-16

0 59