在Python中为每条输出行编号

Question

python：读取文件，然后每行重复两次，将输出行编号

示例：给定此文件：

Invictus

Out of the night that covers me
Black as the pit from pole to pole
I thank whatever gods there may be
For my unconquerable soul

这是输出：

1 Invictus
1 Invictus
2
2
3 Out of the night that covers me
3 Out of the night that covers me
4 Black as the pit from pole to pole
4 Black as the pit from pole to pole
5 I thank whatever gods there may be
5 I thank whatever gods there may be
6 For my unconquerable soul
6 For my unconquerable soul

---

这是我到目前为止的代码，我还无法弄清楚在每行加上双编号所需的循环：

fileicareabout = open("ourownfile","r")
text = fileicareabout.readlines()
count = len(open("ourownfile").readlines(  ))
fileicareabout.close()
def linecount(ourownfile):
    count = 0
    for x in open("ourownfile"):
        count += 1
    return count

for words in text:
    print (str(linecount) + words) * 2
print

Answer 1

您是说在粘贴每行两次时需要增加编号吗？ 所以它必须是：1 Invictus

2罪犯

3

4

5覆盖我的夜晚

如果是这样，您的循环应如下所示：

count = 0
for words in text:
      print(str(count) + words)
      count += 1
      print(str(count) + words)
      count += 1

Answer 2

乘法运算符（ * ）可能很方便。

例：

>>> '15 hello world\n' * 2
'15 hello world\n15 hello world\n'

遵循相同的逻辑：

counter = 1
with open('input.txt') as input_file:
    with open('output.txt', 'w') as output_file:
        for line in input_file:
            output_file.write( '{} {}'.format(counter, line) * 2  )
            counter += 1

input.txt：

hello
world
my
name
is
Sait

output.txt：

1 hello
1 hello
2 world
2 world
3 my
3 my
4 name
4 name
5 is
5 is
6 Sait
6 Sait

Answer 3

您可以使用枚举来保持您的行号计数：

with open("ourownfile") as f:
    for line_no, line in enumerate(f, 1):
        print "{} {}".format(line_no, line)*2,

或使用更新的打印功能（python 3必需）：

from __future__ import print_function

with open("ourownfile") as f:
    for line_no, line in enumerate(f, 1):
        print("{} {}".format(line_no, line)*2, end='')

要获得确切的输出，请跳过第一行：

with open("ourownfile") as f:
    for line_no, line in enumerate(f):
        if line_no == 0:
            continue
        print("{} {}".format(line_no, line)*2, end='')