Question

我有12个月的库存数据包含在12个数据框的列表中。每个数据框具有以下结构：

    'data.frame':   218680 obs. of  19 variables:
 $ Symbol        : Factor w/ 3423 levels "AABC","AACB",..: 1 1 1 1 1 1 1 1 1 1 ...
 $ MktCategory   : Factor w/ 4 levels " NR - Non-Market Maker Reporting Member",..: 4 4 4 4 4 4 4 4 4 4 ...
 $ TSO           : Factor w/ 3352 levels ""," C - ECN",..: 745 745 745 745 745 745 745 745 745 745 ...
 $ TSO_Date      : Factor w/ 180 levels "","01/12/2005",..: 159 159 159 159 159 159 159 159 159 159 ...
 $ X.OfMP        : int  4 4 4 4 4 4 4 4 4 4 ...
 $ MPID          : Factor w/ 739 levels "","ABLE","ABNA",..: 590 668 292 306 313 587 100 681 432 598 ...
 $ MP_type       : Factor w/ 4 levels "","C","M","NR": 3 2 3 3 3 3 2 4 3 3 ...
 $ Total_Vol     : int  0 0 0 0 60000 0 300 2184 0 0 ...
 $ Total_Rank    : int  0 0 0 0 1 0 4 3 0 0 ...
 $ Total_Pct     : int  0 0 0 0 92 0 0 3 0 0 ...
 $ Block_Vol     : int  0 0 0 0 55000 0 0 0 0 0 ...
 $ Block_Rank    : int  0 0 0 0 1 0 0 0 0 0 ...
 $ Block_Pct     : int  0 0 0 0 100 0 0 0 0 0 ...
 $ YTD_Total_Vol : int  100 900 100 2200 124541 18429 10700 7732 13600 200 ...
 $ YTD_Total_Rank: int  16 10 16 9 1 3 5 6 4 14 ...
 $ YTD_Total_Pct : int  0 0 0 0 54 8 5 3 6 0 ...
 $ YTD_Block_Vol : int  0 0 0 0 117500 0 0 0 0 0 ...
 $ YTD_Block_Rank: int  0 0 0 0 1 0 0 0 0 0 ...
 $ YTD_Block_Pct : int  0 0 0 0 100 0 0 0 0 0 ...

我希望将所有数据框合并到一个数据框中，其中每个数据框列出第一列，其余列只是与各个月的符号相关联的Total_Vol和Total_Rank。有点像这样：

符号Total_Vol（month1）总排名（第1个月）Total_Vol（month2）Total_Rank（month2）...

AACC ...
AACE ....
AAON ...
AAPL
AATI
AAUK
ABAX
ABCB
ABCO
ABCW

Answer 1

这应该可行。

install.packages('plyr')
library(plyr)

df_list <- list(df_1[c('Symbol','Total_vol','Total_rank')], 
                df_2[c('Symbol','Total_vol','Total_rank')], 
                df_3[c('Symbol','Total_vol','Total_rank')])

join_all(df_list, by = 'Symbol')

按特定列和行连接数据框列表

1 个答案: