using System;

namespace Science.Physics.GeneralPhysics
{
	/// <summary>
	/// Force
	/// </summary>
	public class Force : Vector
	{
		private void SetDim()
		{
			this.DimensionMass = 1;
			this.DimensionLength = 1;
			this.DimensionTime = -2;
		}
		public Force() 
		{
			SetDim();
		}
		public Force(Mass m, Acceleration a)
		{
			SetDim();
			this.X = m.kg*a.X;
			this.Y = m.kg*a.Y;
			this.Z = m.kg*a.Z;
		}
        public Force(PotentialEnergy U, Position x)
        {
            SetDim();

            Vector v = VectorCalculus.Gradient(U, x);

            this.X = -v.X;
            this.Y = -v.Y;
            this.Z = -v.Z;
        }
		public Force(PotentialEnergy U, Position x, Time t)
		{
			SetDim();

            Vector v = VectorCalculus.Gradient(U, x, t);

            this.X = -v.X;
            this.Y = -v.Y;
            this.Z = -v.Z;
		}
		public double N
		{
			get{return this.Norm;}
		}
        public override string ToString()
        {
            return base.ToString() + "(N)";
        }
	}
}