由于一个数值问题的精确解往往事先不知道，而用数值方法求出的计算解的误差又是不可避免的。因此，数值解是否失真，如何判断──即误差问题，成为大家所关心的重要而又困难的问题，本章只介绍了误差的基本概念和数值计算的若干原则，这对处理数值计算问题是必需的，但是仅这些还远远不能解决工程和科学计算中更为复杂的误差分析问题，还需专门分门别类地进行研究。-as an accurate numerical solution of the problem often did not know in advance, and the numerical methods used to calculate the solution sought by the error is inevitable. Therefore, the numerical solution of whether distortion, how to judge -- namely error, as we are concerned the important and difficult issues, this chapter presents only the basic concept of error and numerical calculation of certain principles, which deal with numerical calculation is necessary, but they are far from alone can not solve engineering and scientific calculations more complex error analysis, specialized categories needed to conduct research.