1 QR codes are two-dimensional bar codes that can contain any alphanumeric text and often feature URLs that direct users to sites where they can learn about an object or place (a practice known as “mobile tagging”). Decoding software on to

QR算法计算一个矩阵的Schur分解。这当然是一个 在特征值的计算中最重要的算法 -QR algorithm to compute the Schur decomposition of a matrix. This is certainly a feature in the calculation of the value of the most important algorithms

矩阵的QR分解定理: 任意nxn实矩阵A, 存在正交阵Q与上三角阵R, 使得A=Q*R-QR matrix decomposition theorem: any nxn real matrix A, the presence of orthogonal matrix Q and the upper triangular matrix R, such that A = Q* R