Pandas DataFrame to List of Dictionaries

Question

Use df.to_dict('records') -- gives the output without having to transpose externally.

In [2]: df.to_dict('records')
Out[2]:
[{'customer': 1L, 'item1': 'apple', 'item2': 'milk', 'item3': 'tomato'},
 {'customer': 2L, 'item1': 'water', 'item2': 'orange', 'item3': 'potato'},
 {'customer': 3L, 'item1': 'juice', 'item2': 'mango', 'item3': 'chips'}]

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

In [1]: df
Out[1]:
   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()
Out[2]:
[{'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 an extension to John Galt's answer -

For the following DataFrame,

   customer  item1   item2   item3
0         1  apple    milk  tomato
1         2  water  orange  potato
2         3  juice   mango   chips

If you want to get a list of dictionaries including the index values, you can do something like,

df.to_dict('index')

Which outputs a dictionary of dictionaries where keys of the parent dictionary are index values. In this particular case,

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

If you are interested in only selecting one column this will work.

df[["item1"]].to_dict("records")

The below will NOT work and produces a TypeError: unsupported type: . I believe this is because it is trying to convert a series to a dict and not a Data Frame to a dict.

df["item1"].to_dict("records")

I had a requirement to only select one column and convert it to a list of dicts with the column name as the key and was stuck on this for a bit so figured I'd share.