Fill column with dictionary values if key can be matched

Question

I have a DataFrame, containing "keys" and "values". In another datframe, i have only the keys. I want this second dataframe to fill a new column if the keys can be matched. Better to see on the example:

df = pd.DataFrame({'text':['bla','bla2','hi'], 'value':['hello','morning','random']})

df1 = pd.DataFrame({'text':['bla','x','hi','y','bla2','hi','bla']})

and i want the output to look like this:

df1
    text     value
0   bla      hello
1   x           
2   hi       random  
3   y
4   bla2     morning
5   hi       random
6   bla      hello

i thought this would be easiest if i create a dictionary from df with text as key and value as values, which i do with this: y=pd.Series(df.value.values,index=df.text).to_dict() which would look like this: y={'bla': 'hello', 'bla2': 'morning', 'hi': 'random'} but now i dont know how to do the "matching"

just did, havent you been able to recreate it with the code provided? — user11638654, Jul 14 '19 at 18:11
i have(Thank you for that) i was wondering about the logic you want to implement :) — anky, Jul 14 '19 at 18:12

score 0 · Answer 1 · answered Jul 14 '19 at 18:10

0

With Dataframe.merge function:

In [70]: df.merge(df1, how='right', on='text').fillna('')                                                                       
Out[70]: 
   text    value
0   bla    hello
1   bla    hello
2  bla2  morning
3    hi   random
4    hi   random
5     x         
6     y

answered Jul 14 '19 at 18:10

RomanPerekhrest

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this is basically it. but is it possible to keep the order of df1? – user11638654 Jul 14 '19 at 18:15

Fill column with dictionary values if key can be matched

1 Answers1