[R] Take a levels

[Sean Davis]

On Apr 27, 2005, at 8:21 AM, Muhammad Subianto wrote:

> Dear all,
> How can I take a levels from a dataset.
> For example,
>
> data(iris)
> x.iris <- iris[,1:4]
> y.iris <- iris[,5]
>> y.iris
>   [1] setosa     setosa     setosa     setosa     setosa     setosa
>   [7] setosa     setosa     setosa     setosa     setosa     setosa
> ....
> [139] virginica  virginica  virginica  virginica  virginica  virginica
> [145] virginica  virginica  virginica  virginica  virginica  virginica
> Levels: setosa versicolor virginica
>
> I want like,
> y.iris level are,
> [] setosa versicolor virginica
>

Muhammad,

See ?unique and ?factor.

Sean