Merge two DataFrames if a value is not present in other DataFrame

Question

I have two datasets as following tf_df:

      Score    keyword
1  0.029827     olive
2  0.089482     London

df:

    keyword
1    olive
2    London 
3    USA

I need to append rows of df in tf_df if value of df['keyword'] is not present in tf_df['keyword'] and tf_df will be

      Score    keyword
1  0.029827     olive
2  0.089482     London 
3  NaN          USA

I have tried following code

for key_word in df['keyword'].to_list():
    if not keyword in tf_df['keyword']:
        tf_df.append(df[trend])

but it is giving KeyError: 'keyword value'. Can someone help me how to perform this task? Thank you

Why not to try merge dfs as it is stated in the wording of your question? ```python tf_df = tf_df.merge(df, on='keyword', how='left') ``` — Artyom Akselrod, Jan 20 '21 at 09:19
@ArtyomAkselrod `how='right'` , left will give only two rows — Suhas Mucherla, Jan 20 '21 at 09:22

score 1 · Accepted Answer · answered Jan 20 '21 at 09:17

1

use pd.merge

tf_df=tf_df.merge(df,how='outer')

Score    keyword
1  0.029827     olive
2  0.089482     London 
3  NaN          USA

answered Jan 20 '21 at 09:17

Suhas Mucherla

1 Answers1