How To Extract Subsets of R Objects

There are number of operations that can be used to extract subsets of R objects.

[  --> an object of same class
[[ --> elements of a list or a data frame
$ --> elements of a list or data frame by name

Here are some examples which show you how to use these operations:

1. Extract elements from vector

2. Extract elements from matrices 

3. Extract elements from list

4. Extract multi-elements

5. Extract specific elements

6. Extract elements from partial name

7. Remove missing values

8. Extract data with conditions

Have fun!