Pandas_Pivot表 - 从合并列的划分中创建其他列

时间:2017-08-11 10:05:20

标签: python pandas pivot pivot-table subset

我试图运行以下功能

def make_europe_view(data):

    data['% Rev'] = data.GrossRevenue_GBP/data.GrossRevenue_GBP.sum()

    tmean = lambda x :stats.trim_mean(x, 0.1)

    pivot = pd.pivot_table(data[(data['New_category_ID'] != 0)&(data['YYYY'] == 2016)], 
                                index = 'New_category',  
                                values=['GrossRevenue_GBP','MOVC_GBP','PM_GBP', '% Rev'],
                                aggfunc= {'MOVC_GBP':tmean,'PM_GBP':tmean,'GrossRevenue_GBP':[np.sum,tmean],'% Rev':np.sum })



    pivot['% PM'] = pivot['PM_GBP']/pivot[('GrossRevenue_GBP')]['<lambda>']
    #pivot['% MOVC'] = pivot['MOVC_GBP']/Tmean_GR
    pivot['Country'] = 'EU'
    pivot['product_cat'] = pivot.index

    #pivot = pivot[['product_cat', '% Rev', 'GrossRevenue_GBP', 'MOVC_GBP', 'PM_GBP', '% PM', '% MOVC', 'Country']]

    return pivot

我想通过截断的均值和总和来汇总总收入,我没有问题生成数据透视表但是在创建一些额外的列时我遇到了问题。具体来说这部分代码:

 pivot['% PM'] = pivot['PM_GBP']/pivot[('GrossRevenue_GBP')]['<lambda>']

我正在尝试创建一个列,通过采用“PM_GBP”的截断平均值来计算PM的截断平均值。列作为GrossRevenue_GBP&#39; GrossRevenue_GBP&#39;的截断均值的百分比柱

它会产生以下错误:

ValueError: Wrong number of items passed 25, placement implies 1

output of pivot:

真的很感激一些帮助。

我运行list()时的数据透视表的列名:

[('GrossRevenue_GBP', '<lambda>'),  ('GrossRevenue_GBP', 'sum'),  ('% Rev', 'sum'),  ('MOVC_GBP', '<lambda>'),  ('PM_GBP', '<lambda>'),  ('Country', ''),  ('product_cat', '')]

1 个答案:

答案 0 :(得分:1)

您可以在列中的MultiIndex中使用元组选择值:

tups = [('GrossRevenue_GBP', '<lambda>'),  ('GrossRevenue_GBP', 'sum'),  ('% Rev', 'sum'),  ('MOVC_GBP', '<lambda>'),  ('PM_GBP', '<lambda>'),  ('Country', ''),  ('product_cat', '')]
idx = list('ab')
cols = pd.MultiIndex.from_tuples(tups)
pivot = pd.DataFrame([[7,4,5,8,4,5,1],
                   [1,5,7,3,9,6,7]], columns=cols, index=idx)
print (pivot)
  GrossRevenue_GBP     % Rev MOVC_GBP   PM_GBP Country product_cat
          <lambda> sum   sum <lambda> <lambda>                    
a                7   4     5        8        4       5           1
b                1   5     7        3        9       6           7
pivot['% PM'] = pivot[('PM_GBP','<lambda>')]/pivot[('GrossRevenue_GBP','<lambda>')]
print (pivot)
  GrossRevenue_GBP     % Rev MOVC_GBP   PM_GBP Country product_cat      % PM
          <lambda> sum   sum <lambda> <lambda>                              
a                7   4     5        8        4       5           1  0.571429
b                1   5     7        3        9       6           7  9.000000

为了简化生活,可以删除MultiIndex并创建列:

#rename columns by dict
pivot = pivot.rename(columns={'<lambda>':'tmean'})
#remove multiindex
pivot.columns = pivot.columns.map('_'.join).str.strip('_')

#simply divide
pivot['% PM'] = pivot['PM_GBP_tmean']/pivot['GrossRevenue_GBP_tmean']
print (pivot)
   GrossRevenue_GBP_tmean  GrossRevenue_GBP_sum  % Rev_sum  MOVC_GBP_tmean  \
a                       7                     4          5               8   
b                       1                     5          7               3   

   PM_GBP_tmean  Country  product_cat      % PM  
a             4        5            1  0.571429  
b             9        6            7  9.000000