如何从文件中删除一行？

Question

我有两个文件（file1和file2），希望将file2的每一行与file1中的所有行进行比较。如果满足此条件： (ln2[1][0] != ln1[1][0]) and (ln2[1][0] != '-') 然后我想从file2中删除file2的当前行，即ln2。 我用python编写了这段代码，但有一个错误

arr1 = []
with open('FA1.txt', 'r') as file1:
    Lines1 = file1.readlines()
    for line in Lines1:
        arr1.append(line.split())

arr2 = []
with open('a.txt', 'r') as file2:
    Lines2 = file2.readlines()
    for line in Lines2:
        arr2.append(line.split())


for ln2 in arr2:
    for ln1 in arr1:
        if (ln2[1][0] != ln1[1][0]) and (ln2[1][0] != '-'):
            text_file = open("a.txt", "a+")
            text_file.write(ln2, '')
            text_file.close()
            #ln2 = ''

另外，我没有使用最后三行代码，而是使用了：(ln2 = '')，但出现了错误：IndexError: string index out of range

文件的内容如下所示：

File1: 
010 00
001 11 
010 10

File2:
00- 0-
0-0 0-
1-- -0
-10 0-

我得到以下错误：

TypeError: write() takes exactly one argument (2 given) 

Answer 1

重写代码会给我们带来：

with open('FA1.txt', 'r') as file1:
    arr1 = [line.split() for line in file1]

with open('a.txt', 'r') as file2:
    arr2 = [line.split() for line in file2]

with open("b.txt", "w") as text_file:
    for line2 in arr2:
        for line1 in arr1:
            if (line2[1][0] != line1[1][0]) and (line2[1][0] != '-'):
                text_file.write(' '.join(line2) + '\n')

我使用了不同的文件作为输出，因为我不想破坏我的测试数据

但是现在，由于循环，您的结果文件b.txt将包含重复的行，并且您将输出所有符合条件的行，而这些行应该被删除

00- 0-
00- 0-
0-0 0-
0-0 0-
-10 0-
-10 0-

根据您的问题，您希望将第二个文件的每一行与第一个文件的每一行进行比较，如果没有任何一行匹配，则写入数据。代码需要反映这一点，因此我们使用if not any ...

with open('FA1.txt', 'r') as file1:
    arr1 = [line.split() for line in file1]

with open('a.txt', 'r') as file2:
    arr2 = [line.split() for line in file2]

with open("b2.txt", "w") as text_file:
    for line2 in arr2:
        if not any((line2[1][0] != line1[1][0]) and (line2[1][0] != '-') for line1 in arr1):
            text_file.write(' '.join(line2))

结果是

1  -0

---

对arr1 = [line.split() for line in file1]的简短解释。我使用列表理解来缩短代码。而且文件是可编辑的，所以我不必在这里使用readlines