パンダ - 空DATAFRAME

Question

私はpandasdataframeに次のデータをロードしようとしています：

jsons_data = pd.DataFrame(columns=['playlist', 'user', 'track', 'count']) 

for index, js in enumerate(json_files): 
    with open(os.path.join(path_to_json, js)) as json_file: 
    json_text = json.load(json_file) 
    #my json layout 
    user = json_text.keys() 
    playlist = 'all_playlists' 
    track = [p for p in json_text.values()[0]] 
    count = [p.values() for p in json_text.values()] 
    print jsons_data 

が、私はempty dataframeを得る：

[u'user1'] 
all_playlists 
[{u'Make You Feel My Love': 1.0, u'I See Fire': 1.0, u'High And Dry': 1.0, u'Fake Plastic Trees': 1.0, u'One': 1.0, u'Goodbye My Lover': 1.0, u'No Surprises': 1.0}] 
[[1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0]] 
[u'user2'] 
all_playlists 
[{u'Codex': 1.0, u'No Surprises': 1.0, u'O': 1.0, u'Go It Alone': 1.0}] 
[[1.0, 1.0, 1.0, 1.0]] 
[u'user3'] 
all_playlists 
[{u'Fake Plastic Trees': 1.0, u'High And Dry': 1.0, u'No Surprises': 1.0}] 
[[1.0, 1.0, 1.0]] 
[u'user4'] 
all_playlists 
[{u'No Distance Left To Run': 1.0, u'Running Up That Hill': 1.0, u'Fake Plastic Trees': 1.0, u'The Numbers': 1.0, u'No Surprises': 1.0}] 
[[1.0, 1.0, 1.0, 1.0, 1.0]] 
[u'user5'] 
all_playlists 
[{u'Wild Wood': 1.0, u'You Do Something To Me': 1.0, u'Reprise': 1.0}] 
[[1.0, 1.0, 1.0]] 
Empty DataFrame 
Columns: [playlist, user, track, count] 
Index: [] 

コードで何が間違っていますか？

EDIT：

jsonファイルはこのように構成されています

{ 
'user1':{ 
'Karma Police':1.0, 
'Roxanne':1.0, 
'Sonnet':1.0, 
'We Will Rock You':1.0, 
}} 

Answer 1

さて、最初のそれと遊ぶためにいくつかのダミーデータは、この問題の理解がはるかに容易になりますことから始めてみましょう：

# Dummy data to play with 
data1 = { 
'user1':{ 
    'Karma Police':1.0, 
    'Roxanne':1.0, 
    'Sonnet':1.0, 
    'We Will Rock You':1.0, 
    } 
} 

data2 = { 
'user2':{ 
    'Karma Police':1.0, 
    'Creep':1.0, 
    } 
} 

は、私たちは以下の使用します何かを説明してみましょう：

In : pd.DataFrame(data1).unstack() 

Out: 
user1 Karma Police  1.0 
     Roxanne    1.0 
     Sonnet    1.0 
     We Will Rock You 1.0 
dtype: float64 

---

# This is where you would normally iterate on the files 
mylist = [] 
for data in [data1, data2]: 
    # Make a dataframe then unstack, 
    # producing a series with a 2-multiindex as above 
    # And append it to the lsit 
    mylist.append(pd.DataFrame(data).unstack()) 

は、今、私たちはそのリストをCONCAT、および

merged = pd.concat(mylist) 
# Renaming to get the right column names 
merged.index.names = ['User', 'Track'] 
merged.name = 'Count' 
# Transpose to a dataframe instead of a Series 
merged = merged.to_frame() 
# Adding a new column with the same value throughout 
merged['Playlist'] = 'all_playlists' 


merged 

をクリーンアップの少しを行いますあなたはこのようにそれを好きではない場合は、その後、reset_indexを呼び出すことができます

：アウト

。

Answer 2

ループの最後で、単に追加：

jsons_data.loc[index] = [playlist, user, track, count] 

を、それが出力します。

playlist     user \ 
0 decaf   [user1] 
1 decaf   [user2] 
2 decaf   [user3] 
3 decaf   [user4] 
4 decaf   [user5] 

               track \ 
0 [Make You Feel My Love, I See Fire, High And D... 
1    [Codex, No Surprises, O, Go It Alone] 
2 [Fake Plastic Trees, High And Dry, No Surprises] 
3 [No Distance Left To Run, Running Up That Hill... 
4  [Wild Wood, You Do Something To Me, Reprise] 

            count 
0 [[1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0]] 
1     [[1.0, 1.0, 1.0, 1.0]] 
2      [[1.0, 1.0, 1.0]] 
3   [[1.0, 1.0, 1.0, 1.0, 1.0]] 
4      [[1.0, 1.0, 1.0]] 

を