Numeric Index Vector

A new vector can be sliced from a given vector with a numeric index vector, which consists of member positions of the original vector to be retrieved.

Here it shows how to retrieve a vector slice containing the second and third members of a given vector s.

Duplicate Indexes

The index vector allows duplicate values. Hence the following retrieves a member twice in one operation.

Out-of-Order Indexes

The index vector can even be out-of-order. Here is a vector slice with the order of first and second members reversed.

Range Index

To produce a vector slice between two indexes, we can use the colon operator ":". This can be convenient for situations involving large vectors.

More information for the colon operator is available in the R documentation.