数据集的融合是将它重构为这样一种形式,每个测量变量独占一行,行中带有要唯一确定这个测量所需的标识符变量。
1、测试数据
ID <- c(1,1,2,2)
Time <- c(1,2,1,2)
X1 <- c(5,3,6,2)
X2 <- c(6,5,1,4)
mydata <- data.frame(ID,Time,X1,X2)
mydata
2、测试2
library(reshape2)
a <- melt(mydata, id="ID")
a
3、测试3
mydata
b <- melt(mydata, id = c("ID","Time"))
b
4、测试4
mydata
c <- melt(mydata, id = c("ID","Time","X1"))
c