4.1.1 函数的概念和作用

函数的概念和作用函数的概念print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")defBirthday():print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")函数的概念函数是组织好的、可重复使用的、用来实现单一或相关联功能的代码段defBirthday():print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")能提高应用的模块性和代码的重复利用率print()、input()等内置函数支持用户自定义函数函数的作用函数的使用可以解决代码冗余print("张三同学，送你一首歌，祝你学习进步")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("李四老师，送您一首歌，祝您工作顺利！")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")defBirthday():print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("Happybirthdaytoyou!")print("张三同学，送你一首歌，祝你学习进步")Birthday()print(“李四老师，送你一首歌，祝您工作顺利！")Birthday()函数的作用函数的封装能够保护内部的数据deffunc():a=1

func()print(“外部的a=“,a)deffunc():a=1print(“内部的a=”,a)func()函数的作用函数能够提高程序的可读性，使得程序模块化cala.pynew_cala.pydefadd(a,b):returna+bdefnum(a,b):returna-bimportmathprint(math.pi)print(math.pow(2,3))print('------自定义函数导入------')importcalaprint(cala.add(2,8))print(cala.num(10,6))函数的作用函数能够提高程序的可维护性和可扩展性需要修改的地方少可维护性是指当需要修改程序的某个模块