Creating a new dataframe column with the number of overlapping words between dataframe and list-CodePudding

I'm having some trouble fixing the following problem: I have a dataframe with tokenised text on every row that looks (something) like the following

index feelings           
1     [happy, happy, sad] 
2     [neutral, sad, mad] 
3     [neutral, neutral, happy]

and lists of words lst1=[happy, fantastic], lst2=[mad, sad], lst3=[neutral] and I want to check for every row in my dataframe how many occurrences of the words in the list there are. So the output would look something like this:

index feelings                  occlst1 occlst2 occlst3      
1     [happy, happy, sad]       2      1        0
2     [neutral, sad, mad]       0      2        1
3     [neutral, neutral, happy] 1      0        2

So, I want to make a new column and compare the dataframe cells to the list.

Thanks in advance!

CodePudding user response：

Use collections.Counter

Setup:

import pandas as pd
from collections import Counter  # Load 'Counter'

df = pd.DataFrame({'feelings': [['happy', 'happy', 'sad'],
                                ['neutral', 'sad', 'mad'],
                                ['neutral', 'neutral', 'happy']]})

lst1 = ['happy', 'fantastic']
lst2 = ['mad', 'sad']
lst3 = ['neutral']

# Create an intermediate dict
occ = {'occlst1': lst1, 'occlst2': lst2, 'occlst3': lst3}

Update: as suggested by @mozway

def count_occ(sr):
    return {col: sum([v for k, v in Counter(sr).items() if k in lst])
                     for col, lst in occ.items()}

df = pd.concat([df, df['feelings'].apply(count_occ).apply(pd.Series)], axis=1)

Note: I didn't use any other columns except feelings for readability. However the concat function restore all columns from df.

Output:

>>> df
                    feelings  occlst1  occlst2  occlst3
0        [happy, happy, sad]        2        1        0
1        [neutral, sad, mad]        0        2        1
2  [neutral, neutral, happy]        1        0        2

CodePudding user response：

You could built a reference Series, to match feelings with the list id. Then explode merge pivot_table:

ref = pd.Series({e: 'occlist_%s' % (i 1) for i,l in enumerate([lst1, lst2, lst3]) for e in l}, name='cols')

## ref:
# happy        occlst1
# fantastic    occlst1
# mad          occlst2
# sad          occlst2
# neutral      occlst3
# Name: cols, dtype: object

df.merge((df.explode('feelings')  # lists to single rows
           # create a new column with list id
           .merge(ref, left_on='feelings', right_index=True)
           # reshape back to 1 row per original index
           .pivot_table(index='index', columns='cols', values='feelings', aggfunc='count', fill_value=0)
          ),
         left_on='index', right_index=True  # merge with original df
        )

NB. I considered here that index is a column, if is is an index, you need to add a df.reset_index() step

output:

   index                   feelings  occlist_1  occlist_2  occlist_3
0      1        [happy, happy, sad]          2          1          0
1      2        [neutral, sad, mad]          0          2          1
2      3  [neutral, neutral, happy]          1          0          2

input:

df = pd.DataFrame({'index': [1, 2, 3],
                   'feelings': [['happy', 'happy', 'sad'],
                                ['neutral', 'sad', 'mad'],
                                ['neutral', 'neutral', 'happy']
                               ]})
lst1=['happy', 'fantastic']
lst2=['mad', 'sad']
lst3=['neutral']