Error in Documentation code

https://docs.unity3d.com/560/Documentation/ScriptReference/Plane.Raycast.html

In my tests the script did nothing, because groundPlane has not been assigned.
fixed code:

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3.  
4. public class ExampleClass : MonoBehaviour {
5.     public Plane groundPlane;
6.     public Transform markerObject;
7.     void Update() {
8.         if (Input.GetMouseButtonDown(0)) {
9.             groundPlane = new Plane(new Vector3(0f, 1f, 0f), 0f);
10.             Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
11.             float rayDistance;
12.             if (groundPlane.Raycast(ray, out rayDistance))
13.                 markerObject.position = ray.GetPoint(rayDistance);
14.            
15.         }
16.     }
17. }

works as expected.

Regards