中文说明：matlab函数编写与调用 ,跟其它的编程语言都一样，但是子函数与主函数要存于不同的文件中，文件名就是函数名字。文件必须保存在current directory中，才能调用。
English Description：
Write and call MATLAB functions , as well as other programming languages, but the Sub with the main function to save in a different file, the file name is the function name. In the file must be saved in the current directory, you can call.