How to add variable key/value pair to list object?

Question

I have two variables, `key` and `value`, and I want to add them as a key/value pair to a list: ``` key = "width" value = 32 mylist = list() mylist$key = value ``` The result is this: ``` mylist # $key # [1] 32 ``` But I would like this instead: ``` mylist # $width # [1] 32 ``` How can I do this?

Accepted Answer

R lists can be thought of as hashes- vectors of objects that can be accessed by name. Using this approach you can add a new entry to the list like so:

```
key <- "width"
value <- 32

mylist <- list()
mylist[[ key ]] <- value
```

Here we use the string stored in the variable key to access a position in the list much like using the value stored in a loop variable i to access a vector through:

```
vector[ i ]
```

The result is:

```
myList
$width
[1] 32
```

How to add variable key/value pair to list object?

Solution

Problem