如何对 Python 循环中迭代的元素求和

Question

我是 Python 的新手，我在理解其逻辑工作原理时遇到了困难。我正在尝试构建一个简单的代码，给定两个列表，找到列表中每个数字之间的差异和 returns 最小差异的平均值。

假设我有这两个列表：

list1=[1, 4, 10]
list2=[2, 3, 6]

使用下面的代码，我可以用第二个列表的数字迭代第一个列表的数字：

for x in list1:

   diff=[abs(y-x) for y in list2]
   print (diff)

[1, 2, 5] # that is, 1-2, 1-3 and 1-6
[2, 1, 2] # that is, 4-2, 4-3 and 4-6
[8, 7, 4] # that is, 10-2, 10-3, 10-6

使用以下代码，我可以找到每次迭代的最小差异：

for x in list1:

   diff=[abs(y-x) for y in list2]
   mindiff=min(int(s) for s in diff)

   print (mindiff)

1 
1 
4

我对此很满意。现在我想对所有最小差异求和，然后将总和除以我计算出的差异数。这是我没有得到的部分。换句话说，我如何构建一个函数来总结 for 循环所做的所有迭代？之后，（在本例中为 6 (1+1+4)）我可以轻松地将差异之和除以 list2 的最大范围。

我该怎么做？

提前感谢您的回答

Answer 1

list1=[1, 4, 10]
list2=[2, 3, 6]

sumOfMinDiffs = 0 # Initialize the sum value to start out at zero

for x in list1:

   diff=[abs(y-x) for y in list2]
   mindiff=min(int(s) for s in diff)
   print (mindiff)

   sumOfMinDiffs += mindiff # Keep track of the sum


maximumRangeOfList2 = max(list2) - min(list2) # I think this is what you mean by "maximum range of list 2"

print(sumOfMinDiffs/maximumRangeOfList2) # Tah dah, this is your answer
# print(sumOfMinDiffs/len(list2)) # This is your answer if you just want to divide by the length of list2

以上代码旨在执行以下操作：

在循环外保留一个总和变量，并在每次循环时递增它
在 for 循环结束时，计算 "maximum range of list 2" 将是什么并将其存储在变量中
对于您的最终答案，只需将总和变量除以范围变量

Answer 2

我认为您可以使用 for 循环外的变量实现您想要的效果，添加每次迭代的值和计算迭代次数的变量。

list1=[1, 4, 10]
list2=[2, 3, 6]


min_sum = 0
n = 0
for x in list1:

    diff=[abs(y-x) for y in list2]
    mindiff=min(int(s) for s in diff)
    min_sum += mindiff
    n+=1

    print (mindiff)

print(min_sum/n)

希望对您有所帮助

Answer 3

以下代码可能会帮助您解决问题。

list1=[1, 4, 10]
list2=[2, 3, 6]

n = len(list2)
sum_min = 0

for x in list1:

    diff=[abs(y-x) for y in list2]
    mindiff=min(int(s) for s in diff)

    sum_min += mindiff  # iterating will keep on adding min of differences 1 + 1 + 4

    print (mindiff)

print(sum_min/n)  # mean minimum difference

我认为，为了计算列表的最小差异的平均值，您需要将最小差异的总和除以每组差异的数量（即 list2 的长度）。如果你想修改代码，我想你已经明白如何去做了。

如何对 Python 循环中迭代的元素求和

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