平均因子分解法,适用于正定矩阵First, let s recall the definition of the Cholesky decomposition: Given a symmetric positive definite square matrix X, the Cholesky decomposition of X is the factorization X=U U, where U is the square root matrix of X, and satisfies:
(1) U U = X
(2) U is upper triangular (that is, it has all zeros below the diagonal).
It seems that the assumption of positive definiteness is necessary. Actually, it is "positive definite" which guarantees the existence of such kind of decomposition. -Average factor decomposition method applied to positive definite matrix First, let s recall the definition of the Cholesky decomposition: Given a symmetric positive definite square matrix X, the Cholesky decomposition of X is the factorization X = UU, where U is the square root matrix of X, and satisfies: (1) UU = X (2) U is upper triangular (that is, it has all zeros below the diagonal). It seems that the assumption of positive definiteness is necessary. Actually, it is positive
找出两个字符串的最长公共子串。
给出一个字符串,请删除该字符串的前导空格和尾随空格,中间的空格若多余1个删减到1个。
我是个菜鸟,但软件会是我终生的事业~我有信心学好它,希望站长通融-Two strings to find the longest common sub-string. Given a string, remove the string leading spaces and trailing spaces, if the extra spaces in the middle of a cut to one. I was a rookie, but the software will be my lifelong career ~ and I am confident to learn it, and hope that owners accommodation
二 维热传导模型的有限元分析。可以改变热导率的参数,仿真时间,平面,输出的数据包括时间为三维!——Dimensional finite element analysis of heat conduction model. Can change the parameters of the conductivity, the simulation time, flat, the output of three-dimensional data, including time!