shaklasah shaklasah - 1 year ago 80
Python Question

Pandas DataFrame to List of Dictionaries (Dics)

I have the following DataFrame:

customer item1 item2 item3
1 apple milk tomato
2 water orange potato
3 juice mango chips

which I want to translate it to list of dictionaries per row

rows = [{'customer': 1, 'item1': 'apple', 'item2': 'milk', 'item3': 'tomato'},
{'customer': 2, 'item1': 'water', 'item2': 'orange', 'item3': 'potato'},
{'customer': 3, 'item1': 'juice', 'item2': 'mango', 'item3': 'chips'}]

Answer Source

Use df.T.to_dict().values(), like below:

In [1]: df
   customer  item1   item2   item3
0         1  apple    milk  tomato
1         2  water  orange  potato
2         3  juice   mango   chips

In [2]: df.T.to_dict().values()
[{'customer': 1.0, 'item1': 'apple', 'item2': 'milk', 'item3': 'tomato'},
 {'customer': 2.0, 'item1': 'water', 'item2': 'orange', 'item3': 'potato'},
 {'customer': 3.0, 'item1': 'juice', 'item2': 'mango', 'item3': 'chips'}]

As John Galt mentions in his answer , you should probably instead use df.to_dict('records'). It's faster than transposing manually.

In [20]: timeit df.T.to_dict().values()
1000 loops, best of 3: 395 µs per loop

In [21]: timeit df.to_dict('records')
10000 loops, best of 3: 53 µs per loop