[SPARK-20849][DOC][FOLLOWUP] Document R DecisionTree - Link Classification Example

## What changes were proposed in this pull request?
in https://github.com/apache/spark/pull/18067, only the regression example is linked

this pr link decision tree classification example to the doc

ping felixcheung

## How was this patch tested?
local build of docs

![default](https://user-images.githubusercontent.com/7322292/33922857-9b00fdd0-e008-11e7-92c2-85a3de52ea8f.png)

Author: Zheng RuiFeng <ruifengz@foxmail.com>

Closes #19963 from zhengruifeng/r_examples.
This commit is contained in:
Zheng RuiFeng 2017-12-13 07:52:21 -06:00 committed by Sean Owen
parent 7453ab0243
commit 58f7c825ae

View file

@ -223,6 +223,14 @@ More details on parameters can be found in the [Python API documentation](api/py
</div>
<div data-lang="r" markdown="1">
Refer to the [R API docs](api/R/spark.decisionTree.html) for more details.
{% include_example classification r/ml/decisionTree.R %}
</div>
</div>
## Random forest classifier