using System;
using System.Windows.Forms;

namespace Science.Mathematics.Calculus
{
	/// <summary>
	/// Interpolation with three different ways.
	/// </summary>
	public class Interpolation1D
	{
		private int n;
		private double[] xa;
		private double[] ya;
        public Interpolation1D()
        {
        }
        public double[] MapFrom
        {
            set { xa = value; n = xa.Length; }
        }
        public double[] MapTo
        {
            set { ya = value; n = ya.Length; }
        }
		public Interpolation1D(double[] mapFrom, double[] mapTo)
		{
            n = mapFrom.Length;
            xa = mapFrom;
            ya = mapTo;
		}
		public void ComputeForPolynomial()
		{
            Science.Mathematics.NumericalRecipes.InterpolationAndExtrapolation.Polint obj
            = new Science.Mathematics.NumericalRecipes.InterpolationAndExtrapolation.Polint();
       
            if (Science.Net.Check())
            {
                obj.polint(xa, ya, n, at);
                dy = obj.Error;
                y = obj.Y;
            }
            else
            {
                try { throw new Exception(); }
                catch (Exception)
                {
                    MessageBox.Show("Please support our authors.",
                        "Invalid user", MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
            }		 		
		}
		public void ComputeForRational()
		{
            Science.Mathematics.NumericalRecipes.InterpolationAndExtrapolation.Ratint obj
            = new Science.Mathematics.NumericalRecipes.InterpolationAndExtrapolation.Ratint();
        
            if (Science.Net.Check())
            {
                obj.ratint(xa, ya, n, at);
                dy = obj.Dy;
                y = obj.Y;	
            }
            else
            {
                try { throw new Exception(); }
                catch (Exception)
                {
                    MessageBox.Show("Please support our authors.",
                        "Invalid user", MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
            }		          		
		}
		public void ComputeForSpline()
		{
			double[] y2 = new Double[n];
            Science.Mathematics.NumericalRecipes.InterpolationAndExtrapolation.Spline obj
            = new Science.Mathematics.NumericalRecipes.InterpolationAndExtrapolation.Spline();
        
            if (Science.Net.Check())
            {
                obj.spline(xa, ya, n, start, end, y2);
            }
            else
            {
                try { throw new Exception(); }
                catch (Exception)
                {
                    MessageBox.Show("Please support our authors.",
                        "Invalid user", MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
            }	
            
            Science.Mathematics.NumericalRecipes.InterpolationAndExtrapolation.Splint obj1
            = new Science.Mathematics.NumericalRecipes.InterpolationAndExtrapolation.Splint();
            obj1.splint(xa, ya ,y2, n, at);
		}
		public void ComputePolynomialCoefficients()
		{
			coef = new double[n];
            Science.Mathematics.NumericalRecipes.InterpolationAndExtrapolation.Polcoe obj
            = new Science.Mathematics.NumericalRecipes.InterpolationAndExtrapolation.Polcoe();
      
            if (Science.Net.Check())
            {
                obj.polcoe(xa, ya, n - 1, coef);
            }
            else
            {
                try { throw new Exception(); }
                catch (Exception)
                {
                    MessageBox.Show("Please support our authors.",
                        "Invalid user", MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
            }		
		}
		private double at = 0.0, y = 0.0, dy = 0.0;
		private double start = 0.0, end = 0.0;
		private double[] coef;
		public double At  // input
		{
			set{at=value;}
		}
        public double DerivativeOfSplineAtStart  // input
        {
            set { start = value; }
        }
        public double DerivativeOfSplineAtEnd  // input
        {
            set { end = value; }
        }
		public double Result   // output
		{
			get{return y;}
		}
		public double Error   // output
		{
			get{return dy;}
		}
		public double[] PolynomialCoefficients  // output
		{
			get{return coef;}
		}	
	}
}