IndexError：列表索引超出范围错误。 （蟒蛇）

Question

当我提交以下代码时：

data = open("DNA Motif.txt", "r")
lines = data.readlines()
large = list(lines[0])
small = list(lines[1])
list = []
counts = []

print large

for first in range(0, len(large)):
    list = []
    if large[first] == small[0]:
        for other in range(0, len(small)):
            if small[other] == large[first + other]:
                list.append(large[first + other])
            if list == small:
                counts.append(str(first + 1))

使用以下数据集：

TTGCGTTTCGCGTTTCTCCGTTGCGTTTCTAGCGTTTCCAGGCGACCGCGTTTCGCGTTTCAGCGTTTCGCGTTTCGCGTTTCGCGTTTCCCCGGGGGCGTTTCGCGTTTCGGCGTTTCCAGCGTTTCCGCGTTTCGCGTTTCGCGTTTCAGCATAGTTAGCGTTTCATCGCGTTTCGCGTTTCTTTTATGCTGTTGCGTTTCTGCTTAGGCGTTTCTACACTCAGCGTTTCGCGTTTCAGCGTTTCAGCGTTTCACAGCGTTTCGCGTTTCTGGCGTTTCGCCGCGTTTCCCGTGCGTTTCATTCTTGCGTTTCTGCGTTTCTCGAGAGCGTTTCGCGTTTCGTACGCGTTTCGCGTTTCTTAAGAGCGTTTCCGCGTTTCGTTACGCGTTGCAAGCGTTTCGGCGTTTCTCAGGCGTTTCGTGCGTTTCTGCGTTTCGCGTTTCTTTGCGTTTCGCGTTTCGAAAGCGTTTCGGTTGCCTACGTATATACTTGCGTTTCGCGTTTCCTTCTAAAGGCGTTTCATAGCGTTTCGCCCTGGAGCGTTTCCGGAGAGCGTTTCTGCGTTTCAGCGTTTCTGCGTTTCAGGAGCGTTTCGGTGAGATTTAGCGTTTCCTATCGGCGTTTCTGGCGTTTCCTCGAAAGCGTTTCAGGCGTTTCATGCGTTTCTGCGTTTCGCGTTTCTCCGGCGTTTCGGCGTTTCGGCGTTTCGCGTTTCAGCGTTTCCAGCGTTTCAAGCGGCGTTTCACGCGTTTCGCGTTTCGCGTTTCGCGTTTCACTGCGTTTCAAGCGTTTCGCGTTTCGCGTTTCAACGCTGCGTTTCAGCGTTTCGCGTTTCGCGTTTCTGACCCGCGTTTCAGCGTTTCTGGGATAGCGTTTCGTGCGTTTCGCGTTTCGCGGTGACGCGTTTC
GCGTTTCGC

我收到此错误：

IndexError: list index out of range

如果你能提供帮助那就太好了。我理解错误是什么，以及我应该如何解决它，但我不知道具体在我的代码中修复了什么。

Answer 1

for first in range(0, len(large)):                       #1
    list = []
    if large[first] == small[0]:
        for other in range(0, len(small)):               #2
            if small[other] == large[first + other]:     #3

1. 最大值first为len(large) - 1。

2. 最大值other为len(small) - 1。

3. 因此，first + other的最大值为len(large) + len(small) - 2。

鉴于您的示例输入中的len(small)为9，first + other在某些时候显然会大于len(large)，但您仍尝试将其用作一个大的索引。

您需要修复逻辑 - 或者，如Martijn Pieters pointed out，使用更简单的方法。