组合多个值，在Python

Question

我有以下格式的数据（CSV文件）：

id, review 
1, the service was great! 
1, staff was friendly. 
2, nice location 
2, but the place was not clean 
2, the motel was okay 
3, i wouldn't stay there next time 
3, do not stay there 

我想数据更改为以下格式：

1, the service was great! staff was friendly. 
2, nice location but the place was not clean the motel was okay 
3, i wouldn't stay there next time do not stay there 

任何帮助将不胜感激。

Answer 1

您可以使用itertools.groupby来分组具有相同编号的连续条目。

import itertools, operator, csv 
with open("test.csv") as f: 
    reader = csv.reader(f, delimiter=",") 
    next(reader) # skip header line 
    for key, group in itertools.groupby(reader, key=operator.itemgetter(0)): 
     print key, ' '.join(g[1] for g in group) 

输出：

1 the service was great! staff was friendly. 
2 nice location but the place was not clean the motel was okay 
3 i wouldn't stay there next time do not stay there 

注：

id, review 
1, the service was great! 
...