Mathf.Atan

Returns the arc-tangent of f - the angle in radians whose tangent is f.

JavaScripts

print (Mathf.Atan(0.5));

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
void Awake() {
print(Mathf.Atan(0.5F));
}
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

def Awake():
print(Mathf.Atan(0.5F))