Splitting a list of dictionaries into several lists of dictionaries

Question

I\'ve been whacking away at this for a while to no avail... Any help would be greatly appreciated.

I have:

[{\'event\': 0, \'voltage\': 1, \'time\':         


        

Answer 1

dict_list = [{'event': 0, 'voltage': 1, 'time': 0},
{'event': 0, 'voltage': 2, 'time': 1},
{'event': 1, 'voltage': 1, 'time': 2},
{'event': 1, 'voltage': 2, 'time': 3},
{'event': 2, 'voltage': 1, 'time': 4},
{'event': 2, 'voltage': 2, 'time': 5},
]

import collections
dol = collections.defaultdict(list)
for d in dict_list:
   k = d["event"]
   dol[k].append(d)

print dol

if you know that your "event" keys are consecutive zero-based integers, you can use a list instead, but the extra complexity may not gain you anything.

defaultdict was added in python 2.5, but the workaround for earlier versions is not hard (see Nick D's code).