变量的解构赋值 ES6允许按照一定模式,从数组和对象中提取值,对变量进行赋值,这被称为解构. 数组的解构赋值 以前,为变量赋值,只能直接指定值: 1 2 3 var a = 1; var b = 2; var c = 3; ES6允许写成下面这样: 1 var [a, b, c] = [1, 2, 3]; 这种写法属于"模式匹配",只要等号两边的模式相同,左边的变量就会被赋予对应的值,如果解构不成功,变量的值就等于undefined,下面是一些使用嵌套数组进行解构的例子: 1 2 3…
“矩阵代数初步”(Introduction to MATRIX ALGEBRA)课程由Prof. A.K.Kaw(University of South Florida)设计并讲授. PDF格式学习笔记下载(Academia.edu) 第10章课程讲义下载(PDF) Summary Definition If $[A]$ is a $n\times n$ matrix, then $[X]\neq \vec0$ is an eigenvector of $[A]$ if $$[A][X] = \…
“矩阵代数初步”(Introduction to MATRIX ALGEBRA)课程由Prof. A.K.Kaw(University of South Florida)设计并讲授. PDF格式学习笔记下载(Academia.edu) 第9章课程讲义下载(PDF) Summary Ill-conditional system A system of equations is considered to be ill-conditioned if a small change in the coe…
“矩阵代数初步”(Introduction to MATRIX ALGEBRA)课程由Prof. A.K.Kaw(University of South Florida)设计并讲授. PDF格式学习笔记下载(Academia.edu) 第8章课程讲义下载(PDF) Summary Algorithm Given a general set of $n$ equations and $n$ unknowns $$\begin{cases}a_{11}x_1 + a_{12}x_2 +\cdots…
“矩阵代数初步”(Introduction to MATRIX ALGEBRA)课程由Prof. A.K.Kaw(University of South Florida)设计并讲授. PDF格式学习笔记下载(Academia.edu) 第7章课程讲义下载(PDF) Summary For a nonsingular matrix $[A]$ on which one can always write it as $$[A] = [L][U]$$ where $[L]$ is a lower tr…
“矩阵代数初步”(Introduction to MATRIX ALGEBRA)课程由Prof. A.K.Kaw(University of South Florida)设计并讲授. PDF格式学习笔记下载(Academia.edu) 第6章课程讲义下载(PDF) Summary Gaussian elimination consists of two steps: Forward Elimination of Unknowns In this step, the unknown is elim…
“矩阵代数初步”(Introduction to MATRIX ALGEBRA)课程由Prof. A.K.Kaw(University of South Florida)设计并讲授. PDF格式学习笔记下载(Academia.edu) 第5章课程讲义下载(PDF) Summary Consistent and inconsistent system A system of equations $$[A][X]=[B]$$ where $[A]$ is called the coefficient…