首页 > 解决方案 > Pandas 复制列元素并根据相关列表应用于另一列

问题描述

这是一个棘手的问题,我很长一段时间都在敲我的头。我有以下数据框。

dct = {'Store': ('A','A','A','A','A','A','B','B','B','C','C','C'),
       'code_num':('INC101','INC102','INC103','INC104','INC105','INC106','INC201','INC202','INC203','INC301','INC302','INC303'),
       'days':('4','18','9','15','3','6','10','5','3','1','8','5'),
       'products': ('remote','antenna','remote, antenna','TV','display','TV','display, touchpad','speaker','Cell','display','speaker','antenna')
}

df = pd.DataFrame(dct)

pts = {'Primary': ('TV','TV','TV','Cell','Cell'),
         'Related' :('remote','antenna','speaker','display','touchpad')
    
}

parts = pd.DataFrame(pts)

print(df)


   Store code_num days           products
0      A   INC101    4             remote
1      A   INC102    18            antenna
2      A   INC103    9    remote, antenna
3      A   INC104   15                 TV
4      A   INC105    3            display
5      A   INC106    6                 TV
6      B   INC201   10  display, touchpad
7      B   INC202    5            speaker
8      B   INC203    3               Cell
9      C   INC301    1            display
10     C   INC302    8            speaker
11     C   INC303    5            antenna

零件数据框仅供参考,我还有另一段代码,它将为每个商店提供相关零件和主要零件的列表。

#For Store A -> TV : ['remote','antenna','speaker'] ; Store B -> Cell :['display','touchpad'] 我预期的数据框是:

   Store code_num days           products      refer
0      A   INC101    4             remote      INC106
1      A   INC102   18            antenna              -> omitted in 1st pass; because >10 days
2      A   INC103    9    remote, antenna      INC106
3      A   INC104   15                 TV              -> omitted in 1st pass; because >10 days
4      A   INC105    3            display      
5      A   INC106    6                 TV      INC106
6      B   INC201   10  display, touchpad      INC203
7      B   INC202    5            speaker      
8      B   INC203    3               Cell      INC203
9      C   INC301    1            display              -> blank because no primary present
10     C   INC302    8            speaker              -> blank because no primary present
11     C   INC303    5            antenna              -> blank because no primary present

我的代码有利于一次执行整个 df。但由于其他业务规则,这将是一个数据片。这意味着 2 和 3 将被省略,因此某些记录的 .iloc 值可能不同。因此,如果您在 <=10 天内对 df 进行子集化,并且如果对您有用,那么它将对我有用。
如果需要更多信息,请告诉我。我知道这很复杂,实际上是一个脑筋急转弯。

标签: pythonpandaslistdataframepandas-groupby

解决方案


复制场景:

您的输入:

dct = {'Store': ('A','A','A','A','A','A','B','B','B','C','C','C'),
       'code_num':('INC101','INC102','INC103','INC104','INC105','INC106','INC201','INC202','INC203','INC301','INC302','INC303'),
       'days':('4','18','9','15','3','6','10','5','3','1','8','5'),
       'products': ('remote','antenna','remote,antenna','TV','display','TV','display,touchpad','speaker','Cell','display','speaker','antenna')
}

df = pd.DataFrame(dct)
pts = {'Primary': ('TV','TV','TV','Cell','Cell'),
         'Related' :('remote','antenna','speaker','display','touchpad')
    
}

parts = pd.DataFrame(pts)
store = {'A':'TV','B':'Cell'}

解决方案:

将部分 df 转换为 Dictionary :

 parts_df_dict = dict(zip(parts['Related'],parts['Primary']))

拆分逗号分隔的子产品并使它们成为单独的行:

new_df = pd.DataFrame(df.products.str.split(',').tolist(), index=df.code_num).stack()
new_df = new_df.reset_index([0, 'code_num'])
new_df.columns = ['code_num', 'Prod_seperated']
new_df = new_df.merge(df, on='code_num', how='left')

创建引用列的逻辑:

store_prod = {}
for k,v in store.items():
    store_prod[k] = k+'_'+v
new_df['prod_store'] = new_df['Store'].map(store_prod)
new_df['p_store'] = new_df['Store'].map(store)
new_df['main_ind'] = ' '
new_df.loc[(new_df['prod_store']==new_df['Store']+'_'+new_df['Prod_seperated'])&(new_df['days'].astype('int')<10),'main_ind']=new_df['code_num']
refer_dic = new_df.groupby('Store')['main_ind'].max().to_dict()
new_df['prod_subproducts'] = new_df['Prod_seperated'].map(parts_df_dict)
new_df['refer']  = np.where((new_df['p_store']==new_df['prod_subproducts'])&(new_df['days'].astype('int')<=10),new_df['Store'].map(refer_dic),np.nan) 

new_df['refer'].fillna(new_df['main_ind'],inplace=True)
new_df.drop(['Prod_seperated','prod_store','p_store','main_ind','prod_subproducts'],axis=1,inplace=True)
new_df.drop_duplicates(inplace=True)

new_df 或所需的输出:

在此处输入图像描述

如果您有任何疑问,请告诉我。


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