pandas groupby 并转换为 json 列表
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pandas groupby and convert to json list
提问by Abhishek Thakur
I have a pandas dataframe like the following
我有一个如下所示的Pandas数据框
idx, f1, f2, f3
1, a, a, b
2, b, a, c
3, a, b, c
.
.
.
87 e, e, e
I need to convert the other columns to list of dictionaries based on idx column. so, final result should be:
我需要将其他列转换为基于 idx 列的字典列表。所以，最终结果应该是：
idx, features
1 , [{f1:a, f2:a, f3:b}, {f1:b, f2:a, f3:c}, {f1:a, f2:b, f3:c}]
.
.
.
87, [{f1: e, f2:e, f3:e}]
Is it possible to do something like this using groupby in pandas?
是否可以在 Pandas 中使用 groupby 来做这样的事情？
采纳答案by jezrael
You can use groupbyby indexand then applyto_json:
您可以使用groupbybyindex和 then ：applyto_json
print df
f1 f2 f3
idx
1 a a b
1 b a c
1 a b c
87 e e e
print df.groupby(level=0).apply(lambda x: x.to_json(orient='records'))
1 [{"f1":"a","f2":"a","f3":"b"},{"f1":"b","f2":"...
87 [{"f1":"e","f2":"e","f3":"e"}]
dtype: object
Or if column idxis not index:
或者如果列idx不是index：
print df
idx f1 f2 f3
0 1 a a b
1 1 b a c
2 1 a b c
3 87 e e e
print df.groupby('idx').apply(lambda x: x.to_json(orient='records'))
idx
1 [{"idx":1,"f1":"a","f2":"a","f3":"b"},{"idx":1...
87 [{"idx":87,"f1":"e","f2":"e","f3":"e"}]
dtype: object
