create one dict from list of dicts in DataFrame

Question

I'm struggling with simple lambda to convert list of nested dicts stored in df column but got stuck.

My df looks like

index   synthkey    celldata
0   870322681ffffff [{'3400_251': {'s': -77, 'q': -8}}, {'3400_426': {'s': -116, 'q': -16}}]
0   87032268effffff [{'3400_376': {'s': -97, 'q': -12}}, {'3400_426': {'s': -88, 'q': -12}}]

What I'd like to achieve is to have it like that:

index   synthkey    celldata
0   870322681ffffff {'3400_251': {'s': -77, 'q': -8},'3400_426': {'s': -116, 'q': -16}}

I've tried multiple attempts like:

df['dicts'] = df['celldata'].apply(lambda x: {}.update(*x)) 

or

df['dicts'] = df.apply(lambda x: {*x['celldata']})

but it got me nowhere near the solution.

Thanks!

Answer 1

Let us try ChainMap

from collections import ChainMap
df['dicts']=df['celldata'].map(lambda x : dict(ChainMap(*x)))

Answer 2

Using a simple for-loop to merge the dictionaries using merge_dict = {**dict_one, **dict_two} .

df = pd.DataFrame([{
    'index': 0,
    'synthkey': '870322681ffffff',
    'celldata': [{'3400_251': {'s': -77, 'q': -8}}, {'3400_426': {'s': -116, 'q': -16}}]
},{
    'index': 0,
    'synthkey': '87032268effffff',
    'celldata': [{'3400_376': {'s': -97, 'q': -12}}, {'3400_426': {'s': -88, 'q': -12}}]
}])

def merge_dicts(list_of_dicts):
    out = {}
    for elem in list_of_dicts:
        out = {**out, **elem}
    return out

df['new'] = df['celldata'].apply(merge_dicts)
print(df.head())
#    index         synthkey                                           celldata  \
# 0      0  870322681ffffff  [{'3400_251': {'s': -77, 'q': -8}}, {'3400_426...   
# 1      0  87032268effffff  [{'3400_376': {'s': -97, 'q': -12}}, {'3400_42...   

#                                                  new  
# 0  {'3400_251': {'s': -77, 'q': -8}, '3400_426': ...  
# 1  {'3400_376': {'s': -97, 'q': -12}, '3400_426':...