Python 複利計算

都是同事問我複利計算，微積分早就還給老師了，不知公式如何，只好自個想啦!
Amt-定期定額
Rate-利率
Y1=Amt*(1+Rate)
Y2=(Y1+Amt)*(1+Rate)
Yn=(Yn-1+Amt)*(1+Rate)

Python sample 程式如下:
# Directory 解法

f={}
base=100
rate =0.05
f[1]=base*(1+rate)
i=1
for i in range(2,5):
 f[i]=(f[i-1]+base)*(1+rate)

for key in f:
 print key,f[key]

#Generator 解法

def f(first,n):
 while True:
     result= (first+100)*(1.05)
     first=result
     n=n+1
     print n,first
     yield first
  
base=100
rate =0.05
i=1
gh=f(0,0)
for i in range(1,5):
 gh.next()

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