using System;
using Science.Mathematics;
using L=Science.Mathematics.IntegralEquation;

namespace ScienceTest.MathematicsTest.IntegralEquationTest
{
	/// <summary>
	/// InhomogeneousVolterraEquationSecondKindTest.
	/// </summary>
	public class InhomogeneousVolterraEquationSecondKindTest
	{
		public InhomogeneousVolterraEquationSecondKindTest()
		{
		}
		private string result;
		public string Result
		{
			get{return result;}
		}
		public void Compute()
		{
			Function.IntIntDoubleDoubleToDouble K
				= new Function.IntIntDoubleDoubleToDouble(kernel);
			Function.IntDoubleToDouble g
				= new Function.IntDoubleToDouble(function);
			L.InhomogeneousVolterraEquationSecondKind eq
				= new L.InhomogeneousVolterraEquationSecondKind();
            eq.Kernel = K;
            eq.KernelFunction = g;
			eq.From = 0.0;
			eq.NumberOfSteps = 30;
			eq.StepSize = 0.001;
			eq.NumberOfCoupledFunctions = 2;
			eq.Solve();
			for(int i=0; i < eq.NumberOfSteps; i++)
			    result += Convert.ToString(eq.At[i])+"\r\n";
			for(int k=0; k < eq.NumberOfCoupledFunctions; k++)
			    for(int i=0; i < eq.NumberOfSteps; i++)
				    result += Convert.ToString(eq.Solution[k,i])+"\r\n";
		}

		private double kernel(int k, int l, double t, double s)
		{
			return (k==0?
				   (l==0? - Math.Exp(t-s) : -Math.Cos(t-s)):
				   (l==0? - Math.Exp(t+s) : -t*Math.Cos(t-s)));
		}
		private double function(int k, double t)
		{
			return (k==0? Math.Cosh(t)+t*Math.Sin(t) :
				2.0*Math.Sin(t)+t*(Math.Sin(t)*Math.Sin(t)+Math.Exp(t)));
		}
	}
}