R - 合并和更新主数据集

Question

这个问题在这里已经有了答案:





How to use merge or replace to update a table in R with multiple columns

(4 个回答)


5年前关闭。




所以，我有两个数据集代表旧地址和当前地址。

> main
idspace   id  x  y move
    198 1238 33  4 stay
    641 1236 36 12 move
    1515 1237 30 28 move

> move
idspace   id x y move
      4 1236 4 1 move

我需要的是将新数据( move )与旧数据( main )合并并更新 main一旦合并。

我想知道是否有可能在一次手术中完成？

更新基于 id , 这是个人标识符。
idspace , x , y是位置ID。

所以，我需要的输出是

> main
  idspace   id   x  y move
       198 1238 33  4 stay
       4   1236 4   1 move # this one is updated 
       1515 1237 30 28 move

我不知道我怎么能做到这一点。

就像是

merge(main, move, by = c('id'), all = T, suffixes = c('old', 'new'))

但是，这是错误的，因为我需要手动进行如此多的操作。

任何解决方案？

数据

> dput(main)
structure(list(idspace = structure(c(2L, 3L, 1L), .Label = c("1515", 
"198", "641"), class = "factor"), id = structure(c(3L, 1L, 2L
), .Label = c("1236", "1237", "1238"), class = "factor"), x = structure(c(2L, 
3L, 1L), .Label = c("30", "33", "36"), class = "factor"), y = structure(c(3L, 
1L, 2L), .Label = c("12", "28", "4"), class = "factor"), move =     structure(c(2L, 
1L, 1L), .Label = c("move", "stay"), class = "factor")), .Names = c("idspace", 
"id", "x", "y", "move"), row.names = c(NA, -3L), class = "data.frame")

> dput(move)
structure(list(idspace = structure(1L, .Label = "4", class = "factor"), 
id = structure(1L, .Label = "1236", class = "factor"), x = structure(1L,  .Label = "4", class = "factor"), 
    y = structure(1L, .Label = "1", class = "factor"), move = structure(1L, .Label = "move", class = "factor")), .Names = c("idspace", 
"id", "x", "y", "move"), row.names = c(NA, -1L), class = "data.frame")`

Answer 1

使用data.table的join+update功能:

require(data.table) # v1.9.6+
setDT(main) # convert data.frames to data.tables by reference
setDT(move)

main[move, on=c("id", "move"),  # extract the row number in 'main' where 'move' matches
       c("idspace", "x", "y") := .(i.idspace, i.x, i.y)] # update cols of 'main' with 
                                                         # values from 'i' = 'move' for 
                                                         # those matching rows


main
#    idspace   id  x  y move
# 1:     198 1238 33  4 stay
# 2:       4 1236  4  1 move
# 3:    1515 1237 30 28 move

此更新 main到位。