How to make dictionary entry a pandas dataframe by specifying columns?

user_17985858 0
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I have a dictionary like this:

mydict ={'9788845278518': [['/book/show/24235201-numero-zero', 'Italian'], ['/book/show/10522.Il_nome_della_rosa', 'Italian']]}

And I would like to make it a dataframe like this:

ISBN, LINK, LANG
9788845278518, /book/show/24235201-numero-zero, Italian
9788845278518, /book/show/10522.Il_nome_della_rosa, Italian

So I tried by doing:

df = pd.DataFrame.from_dict(mydict)

And I wanted to use df.explode and then doing transpose, but it didn't really work because my column is not named. Also, there must be a simpler way to do it...

pandas dataframe python-3.x dictionary python
3 Answers
df = pd.DataFrame.from_dict(mydict)
df = pd.melt(df, var_name='ISBN', value_name='value')
df[['LINK', 'LANG']] = df['value'].apply(pd.Series)
df.drop(columns='value')

melt to move column names to the new ISBN column, and explode the lists into the two new columns LINK, LANG

user_110654650

You could try using a defaultdict before creating a Dataframe, since pandas operations are usually more expensive:

import pandas as pd
from collections import defaultdict

mydict ={'9788845278518': [['/book/show/24235201-numero-zero', 'Italian'], ['/book/show/10522.Il_nome_della_rosa', 'Italian']]}

d = defaultdict(list)
for key,value in mydict.items():
  for v in value:
    d.setdefault('ISBN', []).append(key) 
    d.setdefault('LINK', []).append(v[0])
    d.setdefault('LANG', []).append(v[1])    

df = pd.DataFrame(dict(d))
print(df)

            ISBN                                 LINK     LANG
0  9788845278518      /book/show/24235201-numero-zero  Italian
1  9788845278518  /book/show/10522.Il_nome_della_rosa  Italian
user_96578610

Flatten the dictionary using list comprehension then create a new dataframe

df = pd.DataFrame(
    [(k, *l) for k, v in mydict.items() for l in v], 
    columns=['ISBN', "LINK", 'LANG']
)

print(df)
            ISBN                                 LINK     LANG
0  9788845278518      /book/show/24235201-numero-zero  Italian
1  9788845278518  /book/show/10522.Il_nome_della_rosa  Italian
user_128331660
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