3

我有一个包含这些初始值的足球队信息数据框 df(按比赛(MATCHID))

 TEAMID Venue LEAGUEPOS MATCHID
 WHU     A         5       1
 COV     H        12       1
 EVE     H        15       2
 MNU     A         2       2
 ARS     A         3       3
 LEI     H         4       3

我希望为每个游戏只创建一行,这样它最终看起来像

MATCHID HomeTeam AwayTeam HomePos AwayPos
   1       COV      WHU     12      5      etc.

所以我想创建一些新列,删除其他列并删除重复的行。

我在第一阶段尝试时遇到问题

df$HomeTeam <- df$TEAMID[df$Venue == "H"]

因为这会产生

 TEAMID Venue LEAGUEPOS MATCHID HomeTeam
   WHU     A         5       1      COV
   COV     H        12       1      EVE
   EVE     H        15       2      LEI
   MNU     A         2       2      STH
   ARS     A         3       3      TOT
   LEI     H         4       3      WIM

HomeTeam 只显示每个记录的顺序 TEAMID,Venue = H

4

2 回答 2

5

这可以使用作为reshape基础 R 的一部分的函数轻松实现。

# READ DATA
mydf = read.table(textConnection("
TEAMID Venue LEAGUEPOS MATCHID
 WHU     A         5       1
 COV     H        12       1
 EVE     H        15       2
 MNU     A         2       2
 ARS     A         3       3
 LEI     H         4       3"), 
 sep = "", header = T, colClasses = rep('character', 4))

# RESHAPE DATA
reshape(mydf, idvar = 'MATCHID', timevar = 'Venue', direction = 'wide')

这是产生的输出

  MATCHID TEAMID.A LEAGUEPOS.A TEAMID.H LEAGUEPOS.H
1       1      WHU           5      COV          12
3       2      MNU           2      EVE          15
5       3      ARS           3      LEI           4

注意:另一种方法是使用包中的castmelt函数reshape

require(reshape)
mydf_m = melt(mydf, id = c('MATCHID', 'Venue'))
cast(mydf_m, MATCHID ~ Venue + variable)
于 2011-08-03T17:24:30.313 回答
1

reshape()在 base R 中做你想要的,如果有点笨拙的话。这是您的数据:

con <- textConnection(" TEAMID Venue LEAGUEPOS MATCHID
 WHU     A         5       1
 COV     H        12       1
 EVE     H        15       2
 MNU     A         2       2
 ARS     A         3       3
 LEI     H         4       3
")
dat <- read.table(con, header = TRUE, stringsAsFactors = FALSE)
close(con)

我们reshape()这样,按请求的顺序获取列,并更新列名:

newdat <- reshape(dat, direction = "wide", timevar = "Venue", idvar = "MATCHID")
## reorder
newdat <- newdat[, c(1,4,2,5,3)]
names(newdat) <- c("MatchID","HomeTeam","AwayTeam","HomePos","AwayPos")

这给了我们:

> newdat
  MatchID HomeTeam AwayTeam HomePos AwayPos
1       1      COV      WHU      12       5
3       2      EVE      MNU      15       2
5       3      LEI      ARS       4       3
于 2011-08-03T17:30:29.913 回答