120多个用MATLAB编写的信号处理程序，它们是本书各个章节的大部分例题。用MATLAB编写的程序的名称由“exa”开头，接下来是所在的章、节及例题的序号，如exa010101,指的是第1章第1节（即1.1节）的第1个例题，即例1.1.1。如果该程序是为了说明某一个m文件的应用，则在上述名称的后面跟一个下划线，再在后面加上所说明的MATLAB文件的名称，如exa011001_rand，即是例1.10.1,该例用来说明rand.m文件的应用。(More than 120 signal processing programs written in MATLAB are most of the examples in each chapter of this book. The name of the program written in MATLAB begins with "exa", followed by the ordinal number of the chapters, sections and examples, such as exa0101, which refers to the first example of chapter 1, section 1 (i.e. section 1.1), namely example 1.1.1. If the program is to illustrate the application of an M file, then follow the above name with an underscore, and then add the name of the MATLAB file, such as exa011001_rand, which is Example 1.10.1. This example is used to illustrate the application of rand.m file.)