【对比Python】分组子集运算

任务：计算出指定时间段内各种货物每天的库存状态

Python

1 import pandas as pd
2 import numpy as np
3 starttime = '2015-01-01'
4 endtime = '2015-12-31'
5 stock_data = pd.read_csv('E:\\txt\\stocklog.csv',sep='\t')
6 stock_data['DATE']=pd.to_datetime(stock_data['DATE'])
7 stock_data = stock_data[(stock_data['DATE']>=starttime)&(stock_data['DATE']<=endtime)]
8 stock_data['ENTER']=stock_data['QUANTITY'][stock_data['INDICATOR']!='ISSUE']
9 stock_data['ISSUE']=stock_data['QUANTITY'][stock_data['INDICATOR']=='ISSUE']
10 stock_g = stock_data[['STOCKID','DATE','ENTER','ISSUE']].groupby(by=['STOCKID','DATE'],as_index=False).sum()
11 stock_gr = stock_g.groupby(by='STOCKID',as_index = False)
12 date_df = pd.DataFrame(pd.date_range(starttime,endtime),columns=['DATE'])
13 stock_status_list = []
14 for index,group in stock_gr:
15
16     date_df['STOCKID']=group['STOCKID'].values[0]
17     stock_status = pd.merge(date_df,group,on=['STOCKID','DATE'],how='left')
18     stock_status = stock_status.sort_values(['STOCKID','DATE'])
19     stock_status['OPEN']=0
20     stock_status['CLOSE']=0
21     stock_status['TOTAL']=0
22     stock_status = stock_status.fillna(0)
23     stock_value = stock_status[['STOCKID','DATE','OPEN','ENTER','TOTAL','ISSUE','CLOSE']].values
24     open = 0
25     for value in stock_value:
26         value[2] = open
27         value[4] = value[2] + value[3]
28         value[6] = value[4] - value[5]
29         open = value[6]
30     stock = pd.DataFrame(stock_value,columns = ['STOCKID','DATE','OPEN','ENTER','TOTAL','ISSUE','CLOSE'])
31     stock_status_list.append(stock)
32 stock_status = pd.concat(stock_status_list,ignore_index=True)
  print(stock_status)

集算器

  A B
1 =file("E:\\txt\\stocklog.csv").import@t()  
2 =A1.select(DATE>=date("2015-01-01") && DATE<=date("2015-12-31"))  
3 =A2.groups(STOCKID,DATE;
sum(if(INDICATOR=="ISSUE",QUANTITY,0)):ISSUE,
sum(if(INDICATOR!="ISSUE",QUANTITY,0)):ENTER) 		 
4 =periods(start,end)  
5 for A3.group(STOCKID) =A5.align(A4,DATE)
6   >b=c=0
7   =B5.new(A5.STOCKID:STOCKID,A4(#):DATE,c:OPEN,ENTER,
(b=c+ENTER):TOTAL,ISSUE,
(c=b-ISSUE):CLOSE)
8   >B7.run(ENTER=ifn(ENTER,0),ISSUE=ifn(ISSUE,0))
9   =@|B7

集算器9行代码完成Python32行代码完成的任务，而且再阅读代码时，集算器也更好理解。