分别为R中的data.frame中的每个“in”创建一个变量

Question

我有一个data.frame，它有两个变量es和id。我想添加一个名为weeks的新变量。但是，我希望分别为每个weeks创建id，但要为每个id创建唯一的。

例如，如果es == "SHORT"对所有行的id == 1，我想要相同的数字(例如，3)。如果id == 2是一个不同的数字(例如，1)。

我能在below)基R中实现这一点吗？(参见所需的输出结构

注： SHORT < DEL1 < DEL2表示每个id下的数值。

下面是我尝试过但没有成功的数据和代码：

D <- data.frame(es = c("SHORT", "SHORT", "SHORT","DEL1", "DEL1","DEL1","SHORT", 
            "SHORT", "SHORT", "DEL1", "DEL1", "DEL1","DEL2","DEL2","DEL2"),

                id = c(rep(1, 6), rep(2, 9)) ) 


weeks <- ifelse(D$es == "SHORT", sample(1:5, 6, T), ifelse(D$es == "DEL1", 
                                                        sample(4:8, 7, T),
                                                        sample(7:12, 2, T)))

所需的输出结构(数值是随机的)：

   es  id   weeks
SHORT  1     3
SHORT  1     3
SHORT  1     3
 DEL1  1     5
 DEL1  1     5
 DEL1  1     5
SHORT  2     1
SHORT  2     1
SHORT  2     1
 DEL1  2     6
 DEL1  2     6
 DEL1  2     6
 DEL2  2     8
 DEL2  2     8
 DEL2  2     8

Answer 1

从本质上说，马库斯的意思是。可以用seq_along替换sample或其他函数，如果您需要的星期是随机的。

D <- data.frame(es = c("SHORT", "SHORT", "SHORT","DEL1", "DEL1","DEL1","SHORT", 
                       "SHORT", "SHORT", "DEL1", "DEL1", "DEL1","DEL2","DEL2","DEL2"),

                id = c(rep(1, 6), rep(2, 9)) ) 

weeksTbl <- unique(D)
weeksTbl$weeks <- seq_along(weeksTbl[[1]])

merge(D, weeksTbl, all = TRUE, sort = FALSE)

#>       es id weeks
#> 1  SHORT  1     1
#> 2  SHORT  1     1
#> 3  SHORT  1     1
#> 4   DEL1  1     2
#> 5   DEL1  1     2
#> 6   DEL1  1     2
#> 7  SHORT  2     3
#> 8  SHORT  2     3
#> 9  SHORT  2     3
#> 10  DEL1  2     4
#> 11  DEL1  2     4
#> 12  DEL1  2     4
#> 13  DEL2  2     5
#> 14  DEL2  2     5
#> 15  DEL2  2     5

Answer 2

考虑diff和cumsum对不同分组的顺序排序：

set.seed(8132019)
rand <- sample(1:10, 10, replace=FALSE)

D <- within(D, {        
          diff <- c(0,diff(es)) + c(0, diff(id))
          weeks <- cumsum(ifelse(diff == 0, 0, 1)) + 1

          rm(diff)
    })

D
#       es id weeks
# 1  SHORT  1     1
# 2  SHORT  1     1
# 3  SHORT  1     1
# 4   DEL1  1     2
# 5   DEL1  1     2
# 6   DEL1  1     2
# 7  SHORT  2     3
# 8  SHORT  2     3
# 9  SHORT  2     3
# 10  DEL1  2     4
# 11  DEL1  2     4
# 12  DEL1  2     4
# 13  DEL2  2     5
# 14  DEL2  2     5
# 15  DEL2  2     5