Python adding dict to pandas DataFrame as a column

Question

My DataFrame looks something like this:

A,  B
1,  f

I've got a dictionary which looks like this:

{'M':[1,2,3]}

What i'd like to do is to add the dict into the Dataframe as a column:

A,  B,  C
1,  f,  {'M':[1,2,3]}

It's not important for the C column to be a dict i just need a key value pair where the value is an array.

Could someone explain to men how i could do this?

@jezrael thanks man... was wondering whether it was a dupe, but could not find one so am posting an answer ... — cs95
– cs95, Commented Apr 11, 2018 at 13:56
@colspeed thanks but i had the problem that i had multiple keys and then an error occured the solution was to put the dict into an array and then it worked. At least i do understand it better now Thank you! — swas
– swas, Commented Apr 11, 2018 at 14:19

piRSquared · Accepted Answer · 2018-04-11 13:58:01Z

4

With assign

df.assign(C=[{'M': [1, 2, 3]}])

   A  B                 C
0  1  f  {'M': [1, 2, 3]}

answered Apr 11, 2018 at 13:58

piRSquared

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2 Comments

Ahh thank you very much. My fault was to add the dict directly so i had a value error. The dict must be inside of an array.

@swas if you were trying to add more than one dict, you should have indicated as such in your question

cs95 · Accepted Answer · 2018-04-11 13:55:56Z

3

Assign with loc:

df.loc[0, 'C'] = {'M' : [1, 2, 3]}

df
   A  B                 C
0  1  f  {'M': [1, 2, 3]}

answered Apr 11, 2018 at 13:55

cs95

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BENY · Accepted Answer · 2018-04-11 14:10:08Z

2

Adding []

df['C']=[{'M':[1,2,3]}]
df
Out[11]: 
   A    B                 C
0  1    f  {'M': [1, 2, 3]}

answered Apr 11, 2018 at 14:10

BENY

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