r - 如何使用 fct_relevel 函数重新调整因子列？

Question

我是一个绝对的初学者并且真的很挣扎 - 任何人都可以帮助并告诉我为什么我收到该错误消息以及如何解决它？

这就是我想要做的：

这是我的数据：

Location,S1,S2,S3,S4,C1,C2,TS3
PC_recapped,7.31,7.46,12.17,10.77,6.59,15.94,14.97
PC_infested,3.20,2.63,11.30,5.72,0.00,0.00,16.77
PC_recapped_and_infested,85.71,83.33,30.77,82.35,0.00,0.00,25.00
PC_normal_mites,85.71,100.00,69.23,76.47,0.00,0.00,39.29

Answer 1

要使用包的fct_relevel功能forcats更改因子列中的级别，您需要使用例如包的功能将宽 data.frame格式转换为窄格式。meltreshape2

请看下面的代码：

df <- structure(list(Location = structure(c(3L, 1L, 4L, 2L), .Label = c("PC_infested", 
"PC_normal_mites", "PC_recapped", "PC_recapped_and_infested"), class = "factor"), 
    S1 = c(7.31, 3.2, 85.71, 85.71), S2 = c(7.46, 2.63, 83.33, 
    100), S3 = c(12.17, 11.3, 30.77, 69.23), S4 = c(10.77, 5.72, 
    82.35, 76.47), C1 = c(6.59, 0, 0, 0), C2 = c(15.94, 0, 0, 
    0), TS3 = c(14.97, 16.77, 25, 39.29)), class = "data.frame", row.names = c(NA, 
-4L))

library(reshape2)
library(forcats)

res <- df %>% melt(id = "Location") %>% rename(c("variable" = "type")) %>%
  mutate(type = fct_relevel(type, c("S1", "S2", "S3", "S4", "C1", "C2", "TS3")))

res$type

输出：

 [1] S1  S1  S1  S1  S2  S2  S2  S2  S3  S3  S3  S3  S4  S4  S4  S4  C1  C1  C1  C1  C2  C2  C2  C2  TS3 TS3 TS3 TS3
Levels: S1 S2 S3 S4 C1 C2 TS3