Accessing data in r from list with multiple vectors

Question

A <- list(X = c(Z = 15))

在上面的示例中如何访问15

Answer 1

We can try using a combination of list access syntax along with vector access syntax:

A <- list(X = c(Z = 15))
A$X["Z"]

Z
15

Above A$X refers to the element in the list named X , which happens to be a vector. Then, A$X["Z"] accesses the element in the vector named Z , which is the value 15.

Answer 2

也可以通过索引访问它：

A[[c(1, 1)]] 

Answer 3

You can simply do:

A[[1]]

This gets the first "component" of the list.

 A[[1]]
 Z 
15 

Or if you want to go step by step, then:

A[1][[1]]

     Z 
    15