python - 在 Python 中打印带有约束的行

Question

假设我们有以下包含 a 列和 b 列的文本文件:

D000001 T109
D000001 T195
D000002 T115
D000002 T131
D000003 T073
D000004 T170

我想知道如何产生以下结构:

D000001 T109 T195
D000002 T115 T131
D000003 T073
D000004 T170

下面粘贴的是 Python 的初始框架。

from __future__ import print_function

with open('descr2semtype_short.txt') as f:
    for line in f:
        line = line.rstrip()
        a, b = line.split()
        print(a + ' ' + b)

Answer 1

你可以使用itertools.groupby:

import itertools, operator
with open('descr2semtype_short.txt') as f:
    for key, items in itertools.groupby(
        (line.rstrip().split(None,1) for line in f),
        operator.itemgetter(0)):
        print(key, ' '.join(item[1] for item in items))

它给出了所需的输出:

D000001 T109 T195
D000002 T115 T131
D000003 T073
D000004 T170