从文件打印第N个字符（第8个字符）[Python]

Question

我从文件中转储的序列很长。 现在，我想采用此位序列并能够从中提取每第8位。 例如：

100010010101000001001110010001110000110100001010
000110100000101000000000000000000000000000001101
010010010100100001000100010100100000000000000000
etc

会给：

100110
(extraction from second line)
(extraction from third line)
etc

到目前为止，我有以下代码：

 #/usr/bin/python

 with open("thebits.txt", 'r') as f:
        content = [x.strip('\n') for x in f.readlines()]
        {//logic to extract every 8th bit from each line and print it}

如何从每行中提取每8位？ 。

Answer 1

您可以使用简单的切片：

with open('thebits.txt', 'r') as f:
    for line in f:
        print line.strip()[7::8]

您的示例文件提供：

100110
000001
100000

切片[7::8]从第8个字符开始为您提供第8个字符（从0开始索引7）。

Answer 2

with open(infile) as f:
    print("".join(line[7::8] for line in f))

Answer 3

假设您希望每行分别：

with open('tmp.txt', 'r') as f:
    for line in f.read().splitlines():
        print(line[7::8])