1 #!/usr/bin/env python3
2 # -*- coding:utf-8 -*-
3
4 #01 函数的定义，调用
5 #生日歌
6 def happy():
7 print("Happy birthday to you!")
8
9 def sing(person):
10 happy()
11 happy()
12 print("Happy birthday, dear", person + "!")
13 happy()
14
15 def main():
16 sing("Mike")
17 print()
18 sing("Lily")
19 print()
20 sing("Elmer")
21
22 main()
23
24
25 '''
26 02 改变参数值的函数：
27 函数的形参只接收了实参的值，给形参赋值并不影响实参
28 Python可以通过值来传递参数
29 什么是函数的形参 和 实参？
30 一种是函数定义里的形参，一种是调用函数时传入的实参
31 '''
32
33 #例1 利息计算 addinterest1.py
34 def addInterest(balance,rate): # balance 和 rate 是函数addInterest的形参
35 newBalance = balance * (1 + rate)
36 balance = newBalance
37
38 def main():
39 amount =1000
40 rate = 0.05
41 addInterest(amount,rate) #amount 和rate 是函数addInterest 的实参
42 print(amount)
43
44 main()
45
46 #例2 利息计算 addinterest2.py
47
48 def addInterest(balance, rate):
49 newBalance = balance * (1 + rate)
50 return newBalance
51
52 def test():
53 amount = 1000
54 rate = 0.05
55 amount = addInterest(amount, rate)
56 print(amount)
57
58 test()
59
60 #例3： 处理多个银行账户的程序
61 #addInterest3.py
62 def createTable(principal, apr):
63 #为每一年绘制星号的增长图
64 for year in range(1,11):
65 principal = principal * (1 + apr)
66 print("%2d"%year, end = "")
67 total = caulateNum(principal)
68 print("*" * total)
69 print("0.0k 2.5k 5.0k 7.5k 10.0k")
70 def caulateNum(principal):
71 #计算星号数量
72 total = int(principal * 4 / 1000.0)
73 return total
74 def main():
75 print("This program plots the growth of a 10-year investment.")
76 # 输入本金和利率
77 principal = eval(input("Enter the init principal: "))
78 apr = eval(input("Enter the annualized interest rate: "))
79 #建立图表
80 createTable(principal,apr)
81 main()
