How To Call Pandas Dataframe Apply Function To Return Two Variables

I want to call pandas dataframe apply() function to return two variables For examples: print(word_list) ['abc', 'lmn', ] def is_related_content(x): for y in word_list:

Solution 1:

The function is_related_content is returning tuple for each values in the column the function is applied, so trying to assign the value like that won't work, since each rows will have tuple of values. One solution would be to apply pd.Series to each individual tuples, and assign them back to the list of the columns for the dataframe; the idea is to split the tuples to multiple columns (similar to explode which splits the values to multiple rows):

>>> df[['string', 'substring']] = df['str1'].apply(is_related_content).apply(pd.Series)
>>> df
      str1   string substring
0   abcdefabcdef       abc
1  hijklmn  hijklmn       lmn
2  asddada  

Solution 2:

You need a tuple of Series for the unpacking syntax to work. But apply method is returning a Series of tuples. You can use .str accessor after apply in order to unpack the result as a tuple:

Updates:

s = df['str1'].apply(lambda x: is_related_content(x))
df['string'], df['substring'] = s.str[0], s.str[1]
df#      str1   string substring#0   abcdef   abcdef       abc#1  hijklmn  hijklmn       lmn#2  asddada                   

---

df['string'], df['substring'] = df['str1'].apply(lambda x: is_related_content(x)).str

df#      str1   string substring#0   abcdef   abcdef       abc#1  hijklmn  hijklmn       lmn#2  asddada