李建勝Python執行IRR
pmt = [0,0,0,0] #李建勝程式設計586設定串列list
pmt[0]=float(input('躉繳金額: '))
for nper in range(1,4):
pmt[nper] = float(input('第'+str(nper)+'期回收: '))
def npv(rate):
y = - pmt[0]
for j in range(1,4):
y = y + pmt[j]/(1+rate)**j
return y
a, b, gap, f = 0.0, 1.0, 9.0, 9.0
maxerror = 0.000001
loopNumber = 1
while (gap > maxerror and abs(f) > maxerror and loopNumber < 100):
loopNumber+=1
c = (a+b)/2;
f = npv(c);
if ( abs(f) > maxerror and gap > maxerror):
if ( f>0 ):
a = c
else:
b = c
gap = b-a;
print('李建勝報酬率: ', c)
print('李建勝淨現值: ', f)
print('李建勝迴圈次數: ', loopNumber)