python - 如何同时修改两个相互关联的列表？

Question

关闭。此题需要 details or clarity 。目前不接受答案。

---

想要改进这个问题吗？通过 editing this post 添加详细信息并澄清问题.

已关闭 3 年前。

Improve this question

我有两个空白列表:intitialList和finalList和一个应该进入 initialList 的初始值和样本列表 sampleList = [12,3,1,4,25,3,2,22,12,32,34,2,1,5,7] 。现在我想做的是编写一个程序，首先在 initialList 中插入初始值然后进行一些计算并将值插入 finalList然后 finalList 的第一个值成为 initialList 的第二个值并再次进行一些计算等等。这是一种曲折的东西。值以锯齿形方式填充。我的做法:

intialList = []
finalList = []
intialValue = 30
eff = 0.25
sampleList = [12,3,1,4,25,3,2,22,12,32,34,2,1,5,7]
for a in sampleList:
    if a < 10:
        intialList.append(intialValue)
        finalList.append(intialValue + intialValue*eff)
    else:
        intialList.append(intialValue)
        finalList.append(intialValue - intialValue*eff)
print("initial list:", intialList)
print("final list:", finalList)

我真的不知道如何解决这个问题。期望的输出:

initial list: [30, 22.5, 28.125, 35.156, 43.954, 32.96, 24.72]
finalist list: [22.5, 28.125, 35.156, 43.945, 32.96, 24.72] 

结果存储在finalList中首先是 initial value存储在 initialList 的索引 0 处之后的最终结果来自finalList存储在initialList中。

Answer 1

根据您想要的输出，您希望在 sampleList 迭代期间更改 intalValue:

finalList = []
intialValue = 30
intialList = [intialValue]

eff = 0.25
sampleList = [12,3,1,4,25,3,2,22,12,32,34,2,1,5,7]


for a in sampleList:
    if a < 10:
        calculated_value = intialValue + intialValue * eff

    else:
        calculated_value = intialValue - intialValue * eff

    intialValue = calculated_value
    finalList.append(intialValue)
    intialList.append(intialValue)

print(intialList)    
print(finalList)

输出:

[30, 22.5, 28.125, 35.15625, 43.9453125, 32.958984375, 41.19873046875, 51.4984130859375, 38.623809814453125, 28.967857360839844, 21.725893020629883, 16.294419765472412, 20.368024706840515, 25.460030883550644, 31.825038604438305, 39.78129825554788]
[22.5, 28.125, 35.15625, 43.9453125, 32.958984375, 41.19873046875, 51.4984130859375, 38.623809814453125, 28.967857360839844, 21.725893020629883, 16.294419765472412, 20.368024706840515, 25.460030883550644, 31.825038604438305, 39.78129825554788]