R中的数据框突变

Question

我有以下格式的数据框架：
符号日期时间利润
$ Banknifty 4/1/2010 9:55:00 -1.18％u003Cbr> $ Banknifty 4/1/2010 12:30:00 -2.84％
$ Banknifty 4/1/2010 12:45:00 7.17％u003Cbr> $ Banknifty 5/1/2010 11:40:00 -7.11％
Zeel 26/6/2012 13:50:00 24.75％
Zeel 27/6/2012 15:15:00 -1.90％
Zeel 28/6/2012 9:45:00 37.58％
Zeel 28/6/2012 14:55:00 23.95％
Zeel 29/6/2012 14:20:00 -4.65％
Zeel 29/6/2012 14:30:00 -6.01％
Zeel 29/6/2012 14:55:00 -12.23％
Zeel 29/6/2012 15:15:00 35.13％

我想实现的是将该数据框架转换为数据框，该数据框架的日期为行名，列的符号名称和每天的利润百分比总和。如下所示：

日期银行Zeel
4/1/2010 3.15% 0
5/1/2010 -7.11% 0
26/6/2012 0 24.75%
27/6/2012 0 -1.90%
28/6/2012 0 61.53%
29/6/2012 0 12.24%

我该如何在R中实现？ dplyr 突变还是某些应用功能？

我是R编程的初学者。提前致谢。

R中的数据为

structure(list(Symbol = structure(c(1L, 1L, 1L, 1L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 2L), .Label = c("BANKNIFTY", "ZEEL"), class = "factor"), 
    Date = structure(c(5L, 5L, 5L, 6L, 1L, 2L, 3L, 3L, 4L, 4L, 
    4L, 4L), .Label = c("26/6/2012", "27/6/2012", "28/6/2012", 
    "29/6/2012", "4/1/2010", "5/1/2010"), class = "factor"), 
    Time = structure(c(10L, 2L, 3L, 1L, 4L, 8L, 9L, 7L, 5L, 6L, 
    7L, 8L), .Label = c("11:40:00", "12:30:00", "12:45:00", "13:50:00", 
    "14:20:00", "14:30:00", "14:55:00", "15:15:00", "9:45:00", 
    "9:55:00"), class = "factor"), Profit = structure(c(1L, 4L, 
    12L, 7L, 9L, 2L, 11L, 8L, 5L, 6L, 3L, 10L), .Label = c("-1.18%", 
    "-1.90%", "-12.23%", "-2.84%", "-4.65%", "-6.01%", "-7.11%", 
    "23.95%", "24.75%", "35.13%", "37.58%", "7.17%"), class = "factor")), .Names = c("Symbol", 
"Date", "Time", "Profit"), class = "data.frame", row.names = c(NA, 
-12L))

Answer 1

最快的方法是

require(data.table)
data <- data.table(data)
# Remove the percentage from your file and convert the field to numeric.
data[, Profit := as.numeric(gsub("%", "", Profit))]

data
##           Symbol      Date     Time Profit
##  1: BANKNIFTY  4/1/2010  9:55:00  -1.18
##  2: BANKNIFTY  4/1/2010 12:30:00  -2.84
##  3: BANKNIFTY  4/1/2010 12:45:00   7.17
##  4: BANKNIFTY  5/1/2010 11:40:00  -7.11
##  5:      ZEEL 26/6/2012 13:50:00  24.75
##  6:      ZEEL 27/6/2012 15:15:00  -1.90
##  7:      ZEEL 28/6/2012  9:45:00  37.58
##  8:      ZEEL 28/6/2012 14:55:00  23.95
##  9:      ZEEL 29/6/2012 14:20:00  -4.65
## 10:      ZEEL 29/6/2012 14:30:00  -6.01
## 11:      ZEEL 29/6/2012 14:55:00 -12.23
## 12:      ZEEL 29/6/2012 15:15:00  35.13

# Melt the data so that we can easily dcast afterwards.
molten_data <- melt(data[, list(Symbol, Date, Profit)]

# Create a summary by date and Symbol.
dcast(molten_data, id = c("Symbol", "Date")), Date ~ variable + Symbol, fun = sum)

 ##         Date Profit_BANKNIFTY Profit_ZEEL
 ## 1: 26/6/2012             0.00       24.75
 ## 2: 27/6/2012             0.00       -1.90
 ## 3: 28/6/2012             0.00       61.53
 ## 4: 29/6/2012             0.00       12.24
 ## 5:  4/1/2010             3.15        0.00
 ## 6:  5/1/2010            -7.11        0.00