嗨，我正在尝试在 R 中创建一个对象，然后对数据进行子集化，但收到有关维度的错误消息

Question

I am very new at R so I know the fix is simple, I would appreciate if someone could explain to me though my mistake and how to fix it.

dat4<-c(10, 11)
subDat<-dat4[,c(10,11)]

The error that I am getting is "Error in subDat4<-dat4[,c(10,11)] incorrect number of dimensions"

Thank you in advance

Answer 1

welcome to StackOverflow. You are specifying the dat4 as a vector (one dimension object), but trying to subset as data.frame/tible (2 dimensional objects)...

To specify dat4[a,b] , with a being the indication for rows, and b a indication for columns, you need to have columns and rows (data frame, matrix, ...)

Answer 2

Your data is not a matrix, thus, you can not subset a vector as a matrix. You can only subset matrix with square bracket as you did.

Try

dat4<-c(10, 11)
dat5<-c(12, 13)
mat1<-matrix(c(dat4,dat5),nrow=2)
mat1[1,2]
# 12

You can see my subst states row one column two which prints 12, that is the element that falls on row one column two.

If you want to subset the vector you provided you can go this way.

 dat4[[1]]
 #[1] 10

That show the first element of the vector 'dat4' and

 dat4[[2]]
 #[ 11

Which show the second element of 'dat4'

I hope this answer is of help to you.