Pinch not working

Hi, i have code for scale my objects using pinch. But it's not working, can anyone tell me please? using UnityEngine; using System.Collections; public class Zoom_Button : MonoBehaviour { private Transform Table_Transform = null; public float scaleFactor = 0.5f; // The rate of change of the scale public float minScale = 0.6f; public float maxScale = 2.0f; void Update() { // If there are two touches on the device... if (Input.touchCount == 2) { // Store both touches. Touch touchZero = Input.GetTouch (0); Touch touchOne = Input.GetTouch (1); // Find the position in the previous frame of each touch. Vector2 touchZeroPrevPos = touchZero.position - touchZero.deltaPosition; Vector2 touchOnePrevPos = touchOne.position - touchOne.deltaPosition; // Find the magnitude of the vector (the distance) between the touches in each frame. float prevTouchDeltaMag = (touchZeroPrevPos - touchOnePrevPos).magnitude; float touchDeltaMag = (touchZero.position - touchOne.position).magnitude; // Find the difference in the distances between each frame. float deltaMagnitudeDiff = prevTouchDeltaMag - touchDeltaMag; Table_Transform.localScale += new Vector3(deltaMagnitudeDiff * scaleFactor, deltaMagnitudeDiff * scaleFactor, deltaMagnitudeDiff * scaleFactor); float Table_X, Table_Y, Table_Z; Table_X = Mathf.Clamp(Table_Transform.localScale.x, minScale, maxScale); Table_Y = Mathf.Clamp(Table_Transform.localScale.y, minScale, maxScale); Table_Z = Mathf.Clamp(Table_Transform.localScale.z, minScale, maxScale); Table_Transform.localScale = new Vector3(Table_X, Table_Y, Table_Z); } } } This is the code. Here it didn't show any errors. -Prasanna