7.4 function declaration

1. Default real parameters

If a parameter has a default real parameterAllThe parameter must have a default real parameter.

It can provide real parameters or not, and will overwrite the default value of real parameters.

Design a function with default real parameters. Part of the work is to arrange the form parameters so that the least number of default real parameters is used before the top, and the most likely way is to use the default real parameters.

In a file, the default real parameters can only be set for one form parameter once.

The default real parameters are usually set in the function declaration, and the declaration is placed in the appropriate header file.