【对比Python】分组子集跨行计算并过滤分组结果
任务:找出发生过连续三交易日涨停(涨幅10%)的股票
Python
1 | import pandas as pd |
2 | def con_rise(stock:pd.DataFrame): |
3 | rise_day_list = [] |
4 | rise_num = 0 |
5 | shift_1 = stock['CL']/stock['CL'].shift(1)-1>=0.1 |
6 | for bl in shift_1: |
7 | if bl == False: |
8 | rise_num = 0 |
9 | else: |
10 | rise_num+=1 |
11 | rise_day_list.append(rise_num) |
12 | return max(rise_day_list) |
13 | stock_file = 'E:\\txt\\StockRecords.txt' |
14 | stock = pd.read_csv(stock_file,sep='\t') |
15 | stock_g = stock.groupby(by = ['CODE']) |
16 | good_code = [] |
17 | for index,group in stock_g: |
18 | group = group.sort_values(by='DT') |
19 | group = group.reset_index(drop = True) |
20 | max_rise = con_rise(group) |
21 | if max_rise>=5: |
22 | good_code.append(index) |
23 | print(good_code) |
集算器
A | ||
1 | E:\\txt\\StockRecords.txt | |
2 | =file(A1).import@t() | |
3 | =A2.group(CODE).(~.sort(DT)) | |
4 | =A3.select(func(A5,~)>=5).(~.CODE) | |
5 | func | |
6 | =(rise=0,A5.(rise=if(CL/CL[-1]-1>=0.1,rise=if(!CL[-1],0,rise+1),0))) | |
7 | =max(B6) |
集算器一步一步计算非常明确,1.分组并排序;2.计算涨幅超过0.1的最大天数;3.过滤。自定义的函数同样可以放入循环函数中进行循环计算。