在Pandas上运行AttributeError lower_case.translate和string.punctuation

Question

当我在包含评论的Pandas上运行AttributeError和string.punctuation时，我得到了它。输入的数据很难看。收到的错误是AttributeError: 'DataFrame' object has no attribute 'translate'，完整的错误在下面。

I在注释中尝试了不同的验证

# cleaned_text = lower_case.translate(str.maketrans(string.punctuation, ' '*len(string.punctuation)))
# cleaned_text = lower_case.translator = str.maketrans('', '', string.punctuation)

cleaned_text = lower_case.translate(str.maketrans('', '', string.punctuation))

，我也尝试了这个 ，并在上面添加了一个填充符，希望能修复它。

#checking for nulls if present any
print("Number of rows with null values:")
print(lower_case.isnull().sum().sum())

lower_case.fillna("")

用于数据帧[small sample excel][2] https://github.com/taylorjohn/Simple_RecSys/blob/master/sample-data.xlsx的a

代码

import string
from collections import Counter
import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
from nltk.corpus import stopwords
from nltk.sentiment.vader import SentimentIntensityAnalyzer
from nltk.stem import WordNetLemmatizer
from nltk.tokenize import word_tokenize

# data is in excel formatted ugly and unclean  columns are Artist Names rows are reviews for said Artist
df = pd.read_excel('sample-data.xlsx',encoding='utf8', errors='ignore')

lower_case = df.apply(lambda x: x.astype(str).str.lower())

#checking for nulls if present any
print("Number of rows with null values:")
print(lower_case.isnull().sum().sum())

lower_case.fillna("")


#cleaned_text = lower_case.translate(str.maketrans(string.punctuation, ' '*len(string.punctuation)))
# cleaned_text = lower_case.translator = str.maketrans('', '', string.punctuation)

cleaned_text = lower_case.translate(str.maketrans('', '', string.punctuation))

收到的错误是

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-78-9f23b8a5e8e0> in <module>
      2 # cleaned_text = lower_case.translator = str.maketrans('', '', string.punctuation)
      3 
----> 4 cleaned_text = lower_case.translate(str.maketrans('', '', string.punctuation))

~\anaconda3\envs\nlp_course\lib\site-packages\pandas\core\generic.py in __getattr__(self, name)
   5272             if self._info_axis._can_hold_identifiers_and_holds_name(name):
   5273                 return self[name]
-> 5274             return object.__getattribute__(self, name)
   5275 
   5276     def __setattr__(self, name: str, value) -> None:

AttributeError: 'DataFrame' object has no attribute 'translate'

Answer 1

熊猫DataFrames没有.translate()方法，但是Python有。例如：

import string

my_str = "hello world!"                                                                                                                                                                            
my_str.translate(str.maketrans('', '', string.punctuation)) 

如果要将该转换应用于DataFrame行中的每个列值，则可以在列上使用.map()。.map()方法接受接受列值作为参数的函数，您可以返回转换后的值：

def remove_punctuation(value):
    return value.translate(str.maketrans('', '', string.punctuation))

df["my_cleaned_column"] = df["my_dirty_column"].map(remove_punctuation)

您还可以使用lambda函数，而不是定义新函数：

df["my_cleaned_column"] = df["my_dirty_column"].map(
    lambda x: x.translate(str.maketrans('', '', string.punctuation))
)

如果您有许多需要应用于此的列，则可以这样做：

for column_name in df.columns:
    df[column_name] = df[column_name].map(
        lambda x: x.translate(str.maketrans('', '', string.punctuation))
    )