Python：列の単語の頻度をカウントし、データフレームの別の列に結果を格納する

Question

1つの列の各行に表示される各単語の数をカウントして、私のデータフレームのheadlampという列（ 'word'）。 私は次のダウンコードを試していますが、私はエラーを受け取ります。

for i in range(0,len(headlamp)): 
    headlamp['word'].apply(lambda text: Counter(" ".join(headlamp['Comment'][i].astype(str)).split(" ")).items()) 
--------------------------------------------------------------------------- 
KeyError         Traceback (most recent call last) 
<ipython-input-16-a0c20291b4f5> in <module>() 
    1 for i in range(0,len(headlamp)): 
    ----> 2  headlamp['word'].apply(lambda text: Counter("".join(headlamp['Comment'][i].astype(str)).split(" ")).items()) 

    C:\Users\Rafael\Anaconda2\envs\gl-env\lib\site-packages\pandas\core\frame.pyc in __getitem__(self, key) 
    1995    return self._getitem_multilevel(key) 
    1996   else: 
    -> 1997    return self._getitem_column(key) 
    1998 
    1999  def _getitem_column(self, key): 

    C:\Users\Rafael\Anaconda2\envs\gl-env\lib\site-packages\pandas\core\frame.pyc in _getitem_column(self, key) 
    2002   # get column 
    2003   if self.columns.is_unique: 
    -> 2004    return self._get_item_cache(key) 
    2005 
    2006   # duplicate columns & possible reduce dimensionality 

    C:\Users\Rafael\Anaconda2\envs\gl-env\lib\site-packages\pandas\core\generic.pyc in _get_item_cache(self, item) 
    1348   res = cache.get(item) 
    1349   if res is None: 
    -> 1350    values = self._data.get(item) 
    1351    res = self._box_item_values(item, values) 
    1352    cache[item] = res 

    C:\Users\Rafael\Anaconda2\envs\gl-env\lib\site-packages\pandas\core\internals.pyc in get(self, item, fastpath) 
    3288 
    3289    if not isnull(item): 
    -> 3290     loc = self.items.get_loc(item) 
    3291    else: 
    3292     indexer = np.arange(len(self.items))[isnull(self.items)] 

    C:\Users\Rafael\Anaconda2\envs\gl-env\lib\site-packages\pandas\indexes\base.pyc in get_loc(self, key, method, tolerance) 
    1945     return self._engine.get_loc(key) 
    1946    except KeyError: 
    -> 1947     returnself._engine.get_loc(self._maybe_cast_indexer(key)) 
    1948 
    1949   indexer = self.get_indexer([key], method=method, tolerance=tolerance) 

    pandas\index.pyx in pandas.index.IndexEngine.get_loc (pandas\index.c:4154)() 

    pandas\index.pyx in pandas.index.IndexEngine.get_loc (pandas\index.c:4018)() 

    pandas\hashtable.pyx in pandas.hashtable.PyObjectHashTable.get_item (pandas\hashtable.c:12368)() 

    pandas\hashtable.pyx in pandas.hashtable.PyObjectHashTable.get_item (pandas\hashtable.c:12322)() 

    KeyError: 'word' 

すべてのヘルプは非常にあなたがこれを試すことができます

Answer 1

に感謝されます。

headlamp['word'] = headlamp['Comment'].apply(lambda x: len(x.split())) 

例：

headlamp = pd.DataFrame({'Comment': ['hello world','world','foo','foo and bar']}) 
print(headlamp) 
     Comment 
0 hello world 
1  world 
2   foo 
3 foo and bar 

headlamp['word'] = headlamp['Comment'].apply(lambda x: len(x.split())) 
print(headlamp) 
     Comment word 
0 hello world  2 
1  world  1 
2   foo  1 
3 foo and bar  3 

Answer 2

あなたが欲しいものを達成することができmost_common()方法を使用して。

は、コードのこの部分を使用してお気軽

：

import pandas as pd 
from collections import Counter 

df = pd.DataFrame({'Comment': ['This has has words words words that are written twice twice', 'This is a comment without repetitions', 'This comment, has ponctuations!']}, index = [0, 1, 2]) 

#you must create the new column before trying to assing any value 
df['Words'] = "" 

#counting frequencies 
i = 0 
for row in df['Comment']: 
    df['Words'][i] = str(Counter(row.split()).most_common()) 
    i+=1 

print df 

出力：

           Comment \ 
0 This has has words words words that are writte... 
1    This is a comment without repetitions 
2     This comment, has ponctuations! 

               Words 
0 [('words', 3), ('twice', 2), ('has', 2), ('tha... 
1 [('a', 1), ('comment', 1), ('This', 1), ('is',... 
2 [('This', 1), ('comment,', 1), ('has', 1), ('p...