Each row in DataFrame column is a list. How to remove leading whitespace from second to end entries-CodePudding

I have a dataset that has a "tags" column in which each row is a list of tags. For example, the first entry looks something like this

df['tags'][0]

result = "[' Leisure Trip ', ' Couple ', ' Duplex Double Room ', ' Stayed 6 nights ']"

I have been able to remove the trailing whitespace from all elements and only the leading whitespace from the first element (so I get something like the below).

['Leisure trip', ' Couple', ' Duplex Double Room', ' Stayed 6 nights']

Does anyone know how to remove the leading whitespace from all but the first element is these lists? They are not of uniform length or anything. Below is the code I have used to get the final result above:

clean_tags_list = []
for item in reviews['Tags']:
    string = item.replace("[", "")
    string2 = string.replace("'", "")
    string3 = string2.replace("]", "")
    string4 = string3.replace(",", "")
    string5 = string4.strip()
    string6 = string5.lstrip()
    #clean_tags_list.append(string4.split(" "))
    clean_tags_list.append(string6.split("  "))
clean_tags_list[0]


['Leisure trip', ' Couple', ' Duplex Double Room', ' Stayed 6 nights']

CodePudding user response：

IIUC you want to apply strip for the first element and right strip for the other ones. Then, first convert your 'string list' to an actual list with ast.literal_eval and apply strip and rstrip:

from ast import literal_eval
df.tags.agg(literal_eval).apply(lambda x: [item.strip() if x.index(item) == 0 else item.rstrip() for item in x])

CodePudding user response：

If I understand correctly, you can use the code below :

import pandas as pd

df = pd.DataFrame({'tags': [[' Leisure Trip ', ' Couple ', ' Duplex Double Room ', ' Stayed 6 nights ']]})

df['tags'] = df['tags'].apply(lambda x: [x[0].strip()]   [e.rstrip() for e in x[1:]])

`>>> print(df)`

CodePudding user response：

I was also able to figure it out with the below code. (I know that this isn't very efficient but it worked).

will_clean_tag_list = []
for row in clean_tags_list:
    for col in range(len(row)):
        row[col] = row[col].strip()
    will_clean_tag_list.append(row)

Thank you all for the insight! This has been my first post and I really appreciate the help.