如何使行名和列名成為factor或R中的字段之一？

Question

如何使用行名和列名轉換以下矩陣（或表/數據框），

    A       B
M   27143   18324
F   29522   18875

變成像

27143  M  A
18324  M  B
29522  F  A
18875  F  B

這樣我就可以在R中做一些分析？

Answer 1

您可以使用reshape2包並melt數據。

temp = read.table(header=TRUE, text="    A       B
M   27143   18324
F   29522   18875")
library(reshape2)
temp$id = rownames(temp)
melt(temp)
# Using id as id variables
# id variable value
# 1  M        A 27143
# 2  F        A 29522
# 3  M        B 18324
# 4  F        B 18875

Answer 2

您還可以使用data.table將行名添加為第一列，然后根據其行名將其融化

df<- structure(list(A = c(27143L, 29522L), B = c(18324L, 18875L)), .Names = c("A", 
"B"), class = "data.frame", row.names = c("M", "F"))

library(data.table)
library(reshape2)
setDT(df, keep.rownames = TRUE)[]

#   rn     A     B
#1:  M 27143 18324
#2:  F 29522 18875

(melt(df, id.vars="rn"))
#   rn variable value
#1:  M        A 27143
#2:  F        A 29522
#3:  M        B 18324
#4:  F        B 18875

或使用gather代替melt

library(tidyr)
gather(df, "rn")
#  rn rn value
#1  M  A 27143
#2  F  A 29522
#3  M  B 18324
#4  F  B 18875