How to stop Material lerp?

Questions & Answers
,
1

I wanted to lerp 2 materials and i followed by unity documentation. but after i notice that Materials Lerps Every Time.I want that the only first lerp will be and the lerp will stop.
Here is the code:

public Material[] Materials = new Material[2];
public Renderer ob;
public float speed = 2f;

void Update ()
{
       float lerp = Mathf.PingPong(Time.time, speed) / speed;
       ob.material.Lerp(Materials[0], Materials[1], lerp);
}
2

You use pingpong, which will go up and down.
You can just increment the lerp value by a value (usual deltatime to be framerate indipendant), untill it hits one, which is when the 2nd value in the lerp os fully used