R sapply/lappy与多个ifelse语句
我正在尝试使用sappy或lappy简化以下多个ifelse代码(仍然无法区分它们) 我的目标是根据如下所示的位置分配分数R sapply/lappy与多个ifelse语句,r,if-statement,lapply,sapply,R,If Statement,Lapply,Sapply,我正在尝试使用sappy或lappy简化以下多个ifelse代码(仍然无法区分它们) 我的目标是根据如下所示的位置分配分数 df$Point <- ifelse(df$Placement_v2 <= 1, 10, ifelse(df$Placement_v2 <= 10, 9, ifelse(df$Placement_v2 <= 25, 8, ifelse(df$Placement_v2 <= 50, 7, 1) ))) df$Point您可以创建一个包含值和
df$Point <- ifelse(df$Placement_v2 <= 1, 10,
ifelse(df$Placement_v2 <= 10, 9,
ifelse(df$Placement_v2 <= 25, 8,
ifelse(df$Placement_v2 <= 50, 7, 1) )))
df$Point您可以创建一个包含值和替换项的数据帧。然后可以使用cut
查找适当的值
dict = data.frame(replacement = c(10, 9, 8, 7, 1, 1),
values = c(0, 1, 10, 25, 50, 1e5))
#DATA
set.seed(42)
placement = sample(1:100, 15)
cbind(placement,
new_placement = dict$replacement[as.integer(cut(placement, breaks = dict$values))])
# placement new_placement
# [1,] 92 1
# [2,] 93 1
# [3,] 29 7
# [4,] 81 1
# [5,] 62 1
# [6,] 50 7
# [7,] 70 1
# [8,] 13 8
# [9,] 61 1
#[10,] 65 1
#[11,] 42 7
#[12,] 91 1
#[13,] 83 1
#[14,] 23 8
#[15,] 40 7
有几种方法可以做到这一点。我将使用data.table
library(data.table)
set.seed(123)
df <- data.table(Placement_v2 = runif(200, -10, 100))
结果:
Placement_v2 Point
1: 21.633527 8
2: 76.713565 1
3: 34.987461 7
4: 87.131914 1
5: 93.451401 1
---
196: 41.318597 7
197: 34.751585 7
198: 62.515336 1
199: 6.758128 9
200: 53.015376 1
相反,我将通过对数据进行子集,并按每个子集进行赋值来实现这一点。您可以通过指定每个子集df[Placement_v2=1&Placement_v2来实现这一点,谢谢您的回复。您的代码运行得很好。我只是想了解有关剪切函数的更多信息。我的级别显示为(1,10](10,25)(25,50)(50100)(100200)(200,1e+07)。有没有办法使其类似于1](1,10)(10,25)(25,50)(50,100)(100,200](200?我试图在数据帧中不使用0或1e5。
funky <- function(x) {
if (x <= 1) {
val <- 10
} else if (x <= 10){
val <- 9
} else if (x <= 25){
val <- 8
} else if (x <= 50){
val <- 7
} else {
val <- 1
}
return(val)
}
df[, Point := unlist(lapply(Placement_v2, funky))]
Placement_v2 Point
1: 21.633527 8
2: 76.713565 1
3: 34.987461 7
4: 87.131914 1
5: 93.451401 1
---
196: 41.318597 7
197: 34.751585 7
198: 62.515336 1
199: 6.758128 9
200: 53.015376 1
df[, Point := 1]
df[Placement_v2 <= 50, Point := 7]
df[Placement_v2 <= 25, Point := 8]
df[Placement_v2 <= 10, Point := 9]
df[Placement_v2 <= 1, Point := 10]
Placement_v2 Point
1: 21.633527 8
2: 76.713565 1
3: 34.987461 7
4: 87.131914 1
5: 93.451401 1
---
196: 41.318597 7
197: 34.751585 7
198: 62.515336 1
199: 6.758128 9
200: 53.015376 1