Question

我读了这篇文章

但是我不想加密数据框，只需将其转换为基数为64。我将用回车符分隔的单词列表导入到数据框中的方式如下：

words = pd.read_table("sampleText.txt",names=['word'], header=None)
words.head()

给出

    word
0   difference
1   where
2   mc
3   is
4   the

然后

words['words_encoded'] = map(lambda x: x.encode('base64','strict'), words['word'])
print (words)

给予

                word                   words_encoded
0         difference  <map object at 0x7fad3e89e410>
1              where  <map object at 0x7fad3e89e410>
2                 mc  <map object at 0x7fad3e89e410>
3                 is  <map object at 0x7fad3e89e410>
4                the  <map object at 0x7fad3e89e410>
...              ...                             ...
999995  distribution  <map object at 0x7fad3e89e410>
999996            in  <map object at 0x7fad3e89e410>
999997      scenario  <map object at 0x7fad3e89e410>
999998          less  <map object at 0x7fad3e89e410>
999999          land  <map object at 0x7fad3e89e410>

[1000000 rows x 2 columns]

我不明白为什么我的编码列引用的是地图对象而不是实际数据，所以我尝试：

b64words = words.word.str.encode('base64')
print(b64words)

给予

0        NaN
1        NaN
2        NaN
3        NaN
4        NaN
          ..
999995   NaN
999996   NaN
999997   NaN
999998   NaN
999999   NaN
Name: word, Length: 1000000, dtype: float64

好吧

那让我震惊，所以我阅读了上面的链接答案并尝试了

import base64
def encode(text):
    return base64.b64encode(text)
words['Encoded_Column'] = [encode(x) for x in words]

但是得到

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-89-8cf5a6f1f3a9> in <module>
      2 def encode(text):
      3     return base64.b64encode(text)
----> 4 words['Encoded_Column'] = [encode(x) for x in words]

<ipython-input-89-8cf5a6f1f3a9> in <listcomp>(.0)
      2 def encode(text):
      3     return base64.b64encode(text)
----> 4 words['Encoded_Column'] = [encode(x) for x in words]

<ipython-input-89-8cf5a6f1f3a9> in encode(text)
      1 import base64
      2 def encode(text):
----> 3     return base64.b64encode(text)
      4 words['Encoded_Column'] = [encode(x) for x in words]

~/miniconda3/envs/p37cu10.2PyTo/lib/python3.7/base64.py in b64encode(s, altchars)
     56     application to e.g. generate url or filesystem safe Base64 strings.
     57     """
---> 58     encoded = binascii.b2a_base64(s, newline=False)
     59     if altchars is not None:
     60         assert len(altchars) == 2, repr(altchars)

TypeError: a bytes-like object is required, not 'str'

所以我尝试转换为类似对象这样的字节：

import base64
def encode(text):
    btext = text.str.encode('utf-8')
    return base64.b64encode(btext)
words['Encoded_Column'] = [encode(x) for x in words]

但是得到

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-90-46db6d3688ba> in <module>
      3     btext = text.str.encode('utf-8')
      4     return base64.b64encode(btext)
----> 5 words['Encoded_Column'] = [encode(x) for x in words]

<ipython-input-90-46db6d3688ba> in <listcomp>(.0)
      3     btext = text.str.encode('utf-8')
      4     return base64.b64encode(btext)
----> 5 words['Encoded_Column'] = [encode(x) for x in words]

<ipython-input-90-46db6d3688ba> in encode(text)
      1 import base64
      2 def encode(text):
----> 3     btext = text.str.encode('utf-8')
      4     return base64.b64encode(btext)
      5 words['Encoded_Column'] = [encode(x) for x in words]

AttributeError: 'str' object has no attribute 'str'

在this C示例中，

它们也首先转换为字节字符串，然后转换为base64，但我无法在Python中完成此简单任务。我掉进了这个兔子洞，每一次尝试都使我更加深入。我非常感谢头脑清晰的人可以提供的任何帮助。

Answer 1

map返回一个迭代器，而不是列表，因此pandas只是将其分配给新形成的“ words_encoded”列中的所有插槽。同样，如果您进行了words['all_ones'] = 1，则pandas会在该列下分配1。

第二，“ base64”不是字符串的编解码器，它适用于bytes。您必须选择一种文本编码，然后再对其进行编码。所以，

words['word_encoded'] = words.word.str.encode(
    'utf-8', 'strict').str.encode('base64')

起作用，除了此编码器在base64字符串的末尾添加“ \ n”（我觉得很奇怪）。相反，您可以执行以下任一操作

words['word_encoded'] = words.word.str.encode(
    'utf-8', 'strict').apply(
         base64.b64encode)

# or 

words['word_encoded'] = [base64.b64encode(x.encode('utf-8', 'strict'))
    for x in words.word]

我个人认为第一个是“熊猫”，因为它直接生成了系列，而没有中间列表。

实际解决方案

>>> import base64
>>> import pandas as pd
>>> words = pd.read_table("sampleText.txt",names=['word'], header=None)
__main__:1: FutureWarning: read_table is deprecated, use read_csv instead, passing sep='\t'.
>>> words['word_encoded'] = words.word.str.encode(
...     'utf-8', 'strict').str.encode('base64')
>>> 
>>> words
         word           word_encoded
0  difference  b'ZGlmZmVyZW5jZQ==\n'
1       where          b'd2hlcmU=\n'
2          mc              b'bWM=\n'
3          is              b'aXM=\n'
4         the              b'dGhl\n'
>>> 
>>> words['word_encoded'] = words.word.str.encode(
...     'utf-8', 'strict').apply(
...          base64.b64encode)
>>> 
>>> words
         word         word_encoded
0  difference  b'ZGlmZmVyZW5jZQ=='
1       where          b'd2hlcmU='
2          mc              b'bWM='
3          is              b'aXM='
4         the              b'dGhl'
>>> 
>>> words['word_encoded'] = [base64.b64encode(x.encode('utf-8', 'strict'))
...     for x in words.word]
>>> 
>>> words
         word         word_encoded
0  difference  b'ZGlmZmVyZW5jZQ=='
1       where          b'd2hlcmU='
2          mc              b'bWM='
3          is              b'aXM='
4         the              b'dGhl'

Answer 2

只需从函数主体中删除.str。真实代码：

import base64


def encode(text):
    btext = text.encode('utf-8')
    return base64.b64encode(btext)


words = {'1': 1, '2': 2, '3': 3, 'asdasd': 4}
words['Encoded_Column'] = [encode(x) for x in words]
print(words)

其输出为：

{'1': 1, '2': 2, '3': 3, 'asdasd': 4, 'Encoded_Column': [b'MQ==', b'Mg==', b'Mw==', b'YXNkYXNk']}

如何对python pandas中的列进行base64编码和解码？

2 个答案: