熊貓concat是不可能得到錯誤爲什麼

Question

我喜歡在我的樞紐頂部添加一個總行，但是當我發現concat時，我得到一個錯誤。

>>> table 
      Weight       
Vcountry  1 2 3 4 5 6 7 
V20001         
1    86 NaN NaN NaN NaN NaN 92 
2    41 NaN 71 40 50 51 49 
3   NaN 61 60 61 60 25 62 
4    51 NaN NaN NaN NaN NaN NaN 
5    26 26 20 41 25 23 NaN 

[5 rows x 7 columns] 

那樞軸表

>>> totals_frame 
Vcountry  1 2 3 4 5 6 7 
totalCount 204 87 151 142 135 99 203 

我喜歡它的總加盟

[1 rows x 7 columns] 
>>> pc = [totals_frame, table] 
>>> concat(pc) 

這裏輸出：

reindex_items 
    copy_if_needed=True) 
    File "C:\Python27\lib\site-packages\pandas\core\index.py", line 2887, in reindex 
    target = MultiIndex.from_tuples(target) 
    File "C:\Python27\lib\site-packages\pandas\core\index.py", line 2486, in from_tuples 
    arrays = list(lib.tuples_to_object_array(tuples).T) 
    File "inference.pyx", line 915, in pandas.lib.tuples_to_object_array (pandas\lib.c:43656) 
TypeError: object of type 'long' has no len() 

Answer 1

這裏是一個可能的方式：代替使用pd.concat使用pd.DataFrame.append。有一點擺弄周圍用做索引的，但它仍然是相當整齊，我認爲：

# Just setting up the dataframe: 
df = pd.DataFrame({'country':['A','A','A','B','B','B'], 
        'weight':[1,2,3,1,2,3], 
        'value':[10,20,30,15,25,35]}) 
df = df.set_index(['country','weight']).unstack('weight') 

# A bit of messing about to get the index right: 
index = df.index.values.tolist() 
index.append('Totals') 

# Here's where the magic happens: 
df = df.append(df.sum(), ignore_index=True) 
df.index = index 

這給：

 value   
weight  1 2 3 
A   10 20 30 
B   15 25 35 
Totals  25 45 65