在while循环中拉出一个变量，并在if语句中嵌套if语句

Question

您好，我无法从函数中拉出变量，然后在数学方程中使用它。 我可以使用函数usdExRateRand没有问题，但是当尝试从嵌套if语句中的函数使用usdExRate值时，它只使用初始usdExRateRand而不是来自while循环中新定义的函数，我该如何解决这个问题？

import random 

def whiles(): 
    cur1 = "NZD" 
    cur2 = "USD" 
    usdExRate = round(random.random() * (0.909 - 0.101) + 0.101, 3) 
    print ("usdExRate Initial = $", usdExRate) 
    nzdExRate = round(random.random() * (1.909 - 1.101) + 1.101, 3) 
    print ("nzdExRate Initital = $", nzdExRate) 
    amt = 1000 
    amt2 = 0 
    amtPrev = 0 
    amt2Prev = 0 

    def usdExRateRand(): 
     usdExRate = round(random.random() * (0.909 - 0.750) + 0.750, 3) 
     print ("USD Ex Rate = $", usdExRate,"\n") 
    usdExRateRand() 

    def nzdExRateRand(): 
     nzdExRate = round(random.random() * (1.505 - 1.101) + 1.101, 3) 
     print ("NZD Ex Rate = $", nzdExRate, "\n") 
    nzdExRateRand() 

    while amt > 0: 
     def trade1(): 
    #  usdExRate = round(random.random() * (0.909 - 0.101) + 0.101, 3) 
      print ("TRADE 1") 
      usdExRateRand() 
      if usdExRate > 0: 
    #  def trade1(): 
    #  usdExRate = round(random.random() * (0.909 - 0.101) + 0.101, 3) 
    #  print (usdExRate) 
       if (usdExRate * amt > amt2Prev): 
        print ("My Amount to trade =", cur1," $", amt) 
        print ("my ",cur2,"rate = $", usdExRate) 
        trd1 = amt * usdExRate 
        print ("trade1", cur1,"$", amt," * ",cur2,"$",usdExRate," = $", trd1, "\n") 
        amt2 = trd1 
        amtPrev = amt 

       else: 
        print ("error reluts in a loss\n") 
        trade1() 
     trade1() 

     def trade2(): 
      print ("TRADE 2") 
      nzdExRateRand() 
      if nzdExRate > 0: 
       if (nzdExRate * amt2 > amtPrev): 
        print ("My Amount to trade =", cur2," $",amt2,"\n") 
        print ("my", cur1, "rate = $", nzdExRate) 
        trd2 = amt2 * nzdExRate 
        print ("trade2", cur2,"$", amt2," * ",cur1,"$",nzdExRate," = $", trd2, "\n") 
        amt1 = trd2 
        amt2Prev = amt2 
       else: 
        print ("error results in a loss\n") 

     trade2() 

#   amtPrev = amt 
#   def usdExRateom2(): 
#    usdExRate2 = round(random.random() * (1.909 - 1.101) + 1.101, 3) 
#    print ("my nzd rate", usdExRate2) 
#    
#   if (trd1 * usdExRate2 < amtPrev): 
#     
#    usdExRate2 = round(random.random() * (1.909 - 1.101) + 1.101, 3) 
#     
#   else: 
#    trd2 = trd1 * usdExRate2 
#    print ("trade2 =", trd2) 
#   usdExRateom2() 




whiles() 

希望我复制了代码工作中Spyder的代码的时候得到了我的压痕正确的这个时候，我得到这个输出后可以看到“我的量交易”美元恩率始终0.3不以上值。

TRADE 1 
USD Ex Rate = $ 0.761 

My Amount to trade = NZD $ 1000 
my USD rate = $ 0.3 
trade1 NZD $ 1000 * USD $ 0.3 = $ 300.0 

TRADE 2 
NZD Ex Rate = $ 1.178 

error results in a loss 

TRADE 1 
USD Ex Rate = $ 0.772 

My Amount to trade = NZD $ 1000 
my USD rate = $ 0.3 
trade1 NZD $ 1000 * USD $ 0.3 = $ 300.0 

TRADE 2 
NZD Ex Rate = $ 1.296 

我想要做的是。

def trade(): 
    usdExRaterand() 

这应该给我一个新的usdExRate变量然后我可以在使用if语句

Answer 1

这里是一个非常模糊的例子下面应该只有演示如何值传递给你的函数，以及如何返回值。我不确定你想要达到什么，所以请提供更多信息，我会更新这篇文章。

import random 


def usdExRateRand(): 
    return round(random.random() * (0.909 - 0.750) + 0.750, 3) 


def nzdExRateRand(): 
    return round(random.random() * (1.505 - 1.101) + 1.101, 3) 


def trade1(usdExRate, amtPrev): 
    if usdExRate * amt > amtPrev: 
     # Do your calculations. 
    # Then return the updated amt and previous amt. (If you need them.) 
    return amt, amtPrev 


def trade2(nzdExRate, amtPrev): 
    if nzdExRate * amt > amtPrev: 
     # Do your calculations. 
    # Then return the updated amt and previous amt. 
    return amt, amtPrev 


def main(): 
    amt = 1000 
    amtPrev = amt 

    while amt > 0: 
     usdExRate = usdExRateRand() 
     nzdExRate = nzdExRateRand() 
     print("USD Ex Rate = $", usdExRate) 
     print("NZD Ex Rate = $", nzdExRate) 
     amt, amtPrev = trade(usdExRate, amtPrev) 
     amt, amtPrev = trade2(nzdExRate, amtPrev) 


main()