获取数组迭代错误，并想知道如何修复它

Question

我目前正在为房地产数据建立一个网络刮刀。我在Python中工作，遇到了一个我似乎无法修复的错误。

for i in range(len(s)):
                        if '$' in s[i]:
                                price.append(s[i])

                        elif 'bath' in s[i]:
                                left = s[i].partition(",")[0]
                                right = s[i].partition(",")[2]
                                bed_bath.append(left)
                                sqft_lot.append(right)

                        elif 'fort collins' in s[i].lower():
                                address0 = s[i-1]+' '+s[i]
                                address.append(address0)

                        elif s[i].lower() == 'advertisement':
                                del s[i]

                        else:
                                continue

存在的价值：

                display = Display(visible=0, size=(800, 600))
                display.start()
                browser = webdriver.Firefox()
                browser.get(realtor.format(format))
                p = browser.find_element(By.XPATH, "//ul[@class='jsx-343105667 property-list list-unstyle']")
                content = p.text
                s = re.split('\n',content)

这基本上应该是迭代数组的，并将它们添加到单独的数组价格bed_bath、sqrft_lot、DataFrame中使用的地址中。我知道这是正确的索引，我已经连续地打印了i在范围(len(S))中使用的每一行: print si，它可以工作，但是当我试图实现逻辑时，它只是中断了。

获取错误：

if '$' in s[i]:
**IndexError: list index out of range**

对于为什么会发生这种情况，我们将不胜感激。

Answer 1

正如@quamrana所提到的，最有可能的问题是您执行了del s[i]，所以s变得更短了，因此一些索引将不再存在于s中。我有两个可能的解决办法。修正1：

for i in range(len(s)):
    if i >= len(s): # check if index is still in bounds
        break
    
    if '$' in s[i]:
            price.append(s[i])

    elif 'bath' in s[i]:
            left = s[i].partition(",")[0]
            right = s[i].partition(",")[2]
            bed_bath.append(left)
            sqft_lot.append(right)

    elif 'fort collins' in s[i].lower():
            address0 = s[i-1]+' '+s[i]
            address.append(address0)

    elif s[i].lower() == 'advertisement':
            del s[i]
    else:
            continue

修正2：

indexes_to_remove = []

for i in range(len(s)):
    if '$' in s[i]:
            price.append(s[i])

    elif 'bath' in s[i]:
            left = s[i].partition(",")[0]
            right = s[i].partition(",")[2]
            bed_bath.append(left)
            sqft_lot.append(right)

    elif 'fort collins' in s[i].lower():
            address0 = s[i-1]+' '+s[i]
            address.append(address0)

    elif s[i].lower() == 'advertisement':
            indexes_to_remove.append(i)
    else:
            continue


for index in indexes_to_remove[::-1]: # if you iterate through it backward, you won't have that problem.
    del s[i]

Answer 2

从s中创建一个新列表，并使用筛选和处理的数据填充它。

output_list = []
def process_data(value):
    # your code for processing data
    ...

for i in range(len(s)):
    if s[i] == some_condition(i):
         output_list.append(process_value(s[i])

Answer 3

你要在for循环中删除。这里的示例也会引发一个错误，并且可能更容易理解：

s = [i for i in range(5)]

for i in range(len(s)):
    print(f"{i=} with {s=}")
    del s[i]

输出：

IndexError: list assignment index out of range
i=0 with s=[0, 1, 2, 3, 4]
i=1 with s=[1, 2, 3, 4]
i=2 with s=[1, 3, 4]
i=3 with s=[1, 3]