/*@brief Return the angle between this and another vector
@param v The other vector */
public float angle( ref btVector3 v )
{
float s = btScalar.btSqrt( ( length2() * v.length2() ) );
#if PARANOID_ASSERTS
Debug.Assert( s != (float)(0.0));
#endif
return btScalar.btAcos( ( dot( ref v ) / s ) );
}
