R中

Question

創建子組的權重目前，我有R中的表/ CSV：

Name Value Sector Date 
Company1 100 Financials 3/31/2015 
Company2 100 Energy 3/31/2015 
Company3 100 Healthcare 3/31/2015 
Company4 100 Financials 3/31/2015 
Company5 100 Energy 3/31/2015 
Company6 100 Healthcare 3/31/2015 
Company1 100 Financials 6/30/2015 
Company2 200 Energy 6/30/2015 
Company3 200 Healthcare 6/30/2015 
Company4 200 Financials 6/30/2015 
Company5 200 Energy 6/30/2015 

我想創建是每個季度結束日期，權重爲基礎值的每個部門。

我一直在使用：

cdata <- ddply(Test.Exposure, c("Date", "Sector"), summarise, 
       Sumx1 = sum(Value)) 

這給了我：

  Date  Sector Sumx1 
1  3/31/2015  Energy 200 
2  3/31/2015 Financials 200 
3  3/31/2015 Healthcare 200 
4  6/30/2015  Energy 400 
5  6/30/2015 Financials 300 
6  6/30/2015 Healthcare 400 

1）是否有一種方式來獲得一筆%？

2）是否有可能要爲每個季度結束日期只有一條線，而有這樣一列中的每個部門：

  Financials Energy Healthcare 
3/31/2015 33,33% 33,33% 33,33% 
6/30/2015 ... ... ... 

Answer 1

可以使用xtabs通過rowSums如下：

a <- xtabs(Sumx1~Date+Sector, d) 

#   Sector 
#Date  Energy Financials Healthcare 
# 3/31/2015 200  200  200 
# 6/30/2015 400  300  400 

round(a/rowSums(a)*100, 2) 

#   Sector 
#Date  Energy Financials Healthcare 
# 3/31/2015 33.33  33.33  33.33 
# 6/30/2015 36.36  27.27  36.36 

數據

d <- read.table(text="   Date  Sector Sumx1 
1  3/31/2015  Energy 200 
2  3/31/2015 Financials 200 
3  3/31/2015 Healthcare 200 
4  6/30/2015  Energy 400 
5  6/30/2015 Financials 300 
6  6/30/2015 Healthcare 400", header=T) 

Answer 2

我們可以這樣做dplyr/tidyr

library(dplyr) 
library(tidyr) 
Test.Exposure %>% 
    group_by(Date, Sector) %>% 
    summarise(Sumx1 = sum(Value)) %>% 
    group_by(Date) %>% 
    mutate(Sumx1 = round(100*Sumx1/sum(Sumx1),2)) %>% 
    spread(Sector, Sumx1) 
#  Date Energy Financials Healthcare 
#  <chr> <dbl>  <dbl>  <dbl>  
#1 3/31/2015 33.33  33.33  33.33 
#2 6/30/2015 36.36  27.27  36.36