中文翻译Introduction to Linear Algebra, 5th Edition 2.5节 1 若方阵 A 有逆，则既有 A−1A = I 又有 AA−1 = I。 2 检验可逆性的算法是消元法：A 必须有 n 个（非零）主元。 3 可逆性的代数检验是 A 的行列式：det A 必须非零。 4 可逆性的方程检验为 Ax = 0：x = 0 必须是唯一解。 5 若 A 和 B 都可逆，则 AB 也可逆： (AB)−1 = B−1A−1。 6 AA−1 = I 是关于 A−1 的 n 个列的 n 个方程。高斯—若尔当将 [A I] 消元为 [I A−1]。 7 本书最后一页提供了方阵 A 可逆的 14 个等价条件。 假设 A 是个方阵。我们寻找一个相同大小的“逆矩阵”A−1，使得 A−1 乘以 A 等于 I。无论 A 做 什么，A−1 总是反着来。它们的积是单位矩阵——即对向量什么都不做，因此 A−1Ax = x。然而 A−1 可能不存在。 一个矩阵的主要作用是与一个向量 x 相乘。将 Ax = b 乘上 A−1 得出 A−1Ax = A−1b。这就是 x = A−1b。乘

12.3 实例的SPSS输出结果详解 （1）巴特利特球度检验和KMO检验 首先表15-3显示了对数据进行因子分析适用性检验 的结果。巴特利特球度检验统计量的观测值等于119. 915,。如果显著性水平等于0.05，由于概率P值小于 显著性水平，应拒绝原假设，认为相关系数矩阵与 单位阵有显著差异。同时，KMO值为0.763，根据Kai ser给出的KMO度量标准可知原有变量适合进行因子 分析。

This book is designed for an introductory course on formal languages, automata, computability, and related matters. These topics form a major part of what is known as the theory of computation. A course on this subject matter is now standard in the computer science curriculum and is often taught fairly early in the program. Hence, the prospective audience for this book consists primarily of sophomores and juniors majoring in computer science or computer engineering.

Operations management is important. It is concerned with creating the services and products upon which we all depend. And all organizations produce some mixture of services and products, whether that organization is large or small, manufacturing or service, for profit or not for profit, public or private. Thankfully, most com- panies have now come to understand the importance of operations. This is because they have realized that effective operations management gives the potential to improve both efficiency and customer service simulta- neously. But more than this, operations management is everywhere, it is not confined to the operations function. All managers, whether they are called Operations or Marketing or Human Resources or Finance, or what- ever, manage processes and serve customers (internal or external). This makes, at least part of their activities ‘operations’.

《Lens Design》_Fourth Edition 【Milton Laikin】

The algorithm design manual 2nd edition. 高清无水印版本。所有版权归原作者，仅供学习交流

database system concepts. 英文原版。英文 好看这本很好

Power-System-Analysis-And-Design fifth edition J.D.Glover

Code alone isn’t enough. Sure, it’s what the computer runs, but code has to come from somewhere. A programmer has to sit down and decide what features to include, how they should be implemented, what other software to utilize, and how to provide hooks for future enhancements to be added. It’s easy to skip straight to code, ignoring the cognitive process that produces it, but great programmers always have reasons for the decisions they make. With a framework, like Django, many such decisions have already been made, and the tools provided are shaped by these decisions, and by the programmers who made them. By adopting these philosophies in your own code, not only will you be consistent with Django and other applications, but you may even be amazed at what you’re able to accomplish. Beneath even the simplest code is the thought process that went into its creation. Decisions were made about what it should do and how it should do it. This thought process is a step often overlooked in books and manuals, leading to an army of technicians slaving away, writing code that manages to accomplish the task at hand but without a vision for its future. While the rest of this book will explain in detail the many basic building blocks Django provides for even the most complicated of projects, this chapter will focus on even more fundamental aspects of the framework. For those readers coming from other backgrounds, the ideas presented in this chapter may seem considerably foreign, but that doesn’t make them any less important. All programmers working with Python and Django would do well to have a solid understanding of the reasons Django works the way it does, and how those principles can be applied to other projects. You may want to read this chapter more than once, and perhaps refer to it often as you work with Django. Many of the topics are common knowledge in the Django community, so reading this chapter carefully is essential if you plan to interact with other programmers.

Data Structures and Algorithms in Java 6th Edition.2014.pdf数据结构与算法 纯英文 java