I want to make the mouse rotate an object. How do I make this code work

Questions & Answers
1

What do i put inside the brackets?
This is the code:

using UnityEngine;
using System.Collections;

public class PlayerController : MonoBehaviour {

	public float rspeed = 20;

    private Rigidbody rig;

	// Use this for initialization
	void Start () 
    {
        rig = GetComponent<Rigidbody>();
	}
	
	// Update is called once per frame
	void Update () 
    {
		float mouse = Input.GetAxis("Mouse Y");
		
		Vector3 rotation = new Vector3(0, mouse, 0) * rspeed * Time.deltaTime;
		
		rig.MoveRotation(??????);
	}
}
2

put “Quaternion.Euler(rotation)” inside the bracket, however, if you are not storing the value of your current rotation, the object will reset to a 0,0,0 rotation. the reason being, moving the mouse in one direction will give 1, moving it in the opposite will give -1, and not moving it at all will give 0. plugging in 0 as the y vector3 in your “rotation” vector, will essentially make it Vector3.zero. Multiplying anything by 0 will return 0. By storing the rotation in the current frame, even if mouse input is 0, the desired rotation will be the current rotation

    public float rspeed = 20;
    public float smoothness = 5;
    private Rigidbody rig;

    // Use this for initialization
    void Start()
    {
        rig = GetComponent<Rigidbody>();
    }

    // Update is called once per frame
    void Update()
    {

        //get the current mouse input. Will be 1, 0, or -1
        float mouse = Input.GetAxis("Mouse Y");

        //the desired rotation, affecting the Y value only, will be the current value of the rotation in this frame + ("mouse" (1,0,-1) * speed)
        Vector3 desiredRot = new Vector3(0, rig.rotation.eulerAngles.y + (mouse * rspeed), 0);

        //Slerp the current rotation to the desired rotation over delta time. 
        //Higher smoothness will make it snap to the desired rotation fast, lower values will make it rotate slower
        rig.rotation = Quaternion.Slerp(rig.rotation, Quaternion.Euler(desiredRot), Time.deltaTime * smoothness);
    }