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

namespace ScienceTest.MathematicsTest.OrdinaryDifferentialEquationTest
{
	/// <summary>
	/// EquationTest
	/// </summary>
	public class EquationWithInitialConditionTest
	{
		public EquationWithInitialConditionTest()
		{
		}
		private string result;
		public string Result
		{
			get{return result;}
		}
		public void Compute()
		{
			double[] y = new double[2];  // two variables

			L.InitialCondition ic = new L.InitialCondition();		
			ic.At = 0.0;  // initial independent variable
			y[0]=10.0;    // initial 0-th component value
            y[1] = 0.0;   // initial 1-st component value
			ic.Value = y; // initial value

            Function.ToLastType<double, double[], double[]> ff = new Function.ToLastType<double, double[], double[]>(RightHandSide);
            L.EquationWithInitialCondition eq
                = new L.EquationWithInitialCondition(ff, ic, 10.0, 100);
            eq.Solve();

            for (int i = 0; i <= 100; i++)
            {
                result += i.ToString() + "\t";
                result += eq.IndependentVariable[i].ToString() + "\t";
                result += eq.Solution[0, i].ToString() + "\t";
                result += eq.Solution[1, i].ToString() + "\r\n";
            }
		}
		// change functions as you wish
		private double[] RightHandSide(double x, double[] y) 
		{
			double[] dydxatx = new Double[y.Length];
			dydxatx[0] = y[1];
			dydxatx[1] = - y[0];           
			return dydxatx;
		}
	}
}
/*
0	0	10	0
1	0.1	9.95004165258213	-0.998334171832112
2	0.2	9.80066577775418	-1.98669331125595
3	0.3	9.55336488947271	-2.95520206634958
4	0.4	9.21060993551015	-3.8941834278203
5	0.5	8.77582560927138	-4.79425539900887
6	0.6	8.25335613465534	-5.64642475063038
7	0.7	7.64842185432532	-6.44217688906009
8	0.8	6.96706707156094	-7.17356092335089
9	0.9	6.21609965838548	-7.83326910654491
10	1	5.40302303363165	-8.41470985269459
11	1.1	4.53596119090944	-8.91207359836952
12	1.2	3.62357752584306	-9.32039085007585
13	1.3	2.6749882735528	-9.63558183778692
14	1.4	1.69967142139168	-9.85449727868326
15	1.5	0.707372008637011	-9.97494984338252
16	1.6	-0.291995231719315	-9.99573600690871
17	1.7	-1.28844494392631	-9.9166480797209
18	1.8	-2.27202095050393	-9.7384762825794
19	1.9	-3.23289567646542	-9.46300084868897
20	2	-4.16146836861069	-9.09297423953713
21	2.1	-5.04846104174215	-8.63209363797858
22	2.2	-5.885011161654	-8.08496400986593
23	2.3	-6.66276019634775	-7.45705209352133
24	2.4	-7.37393713397204	-6.75463177751147
25	2.5	-8.01143612921167	-5.98472141371381
26	2.6	-8.56888750273583	-5.15501369217931
27	2.7	-9.04072138497496	-4.27379877822148
28	2.8	-9.42222336891196	-3.34988147739918
29	2.9	-9.709581612169	-2.39249326564098
30	3	-9.89992492407566	-1.41120005537795
31	3.1	-9.99135145681827	-0.415806609533736
32	3.2	-9.98294770914071	0.583741439037669
33	3.3	-9.87479764942014	1.57745694858593
34	3.4	-9.66798187584665	2.55541101969514
35	3.5	-9.36456682269465	3.50783226696305
36	3.6	-8.96758411263867	4.42520441834369
37	3.7	-8.48100026319288	5.29836139615237
38	3.8	-7.90967706140452	6.11857889705581
39	3.9	-7.25932298121528	6.87766157702045
40	4	-6.53643614618044	7.56802493314527
41	4.1	-5.74823940307264	8.1827710835874
42	4.2	-4.90260815368176	8.71575768867806
43	4.3	-4.00799166650721	9.16165932300017
44	4.4	-3.07332865457313	9.51602068519316
45	4.5	-2.1079579617413	9.77530111427056
46	4.6	-1.12152524931332	9.93690996728719
47	4.7	-0.123886620429179	9.99923250380087
48	4.8	0.874989843606117	9.96164601527692
49	4.9	1.86512369203913	9.8245260521764
50	5	2.83662185024603	9.58924267126381
51	5.1	3.77977742363977	9.25814674583944
52	5.2	4.68516670305085	8.83454647951564
53	5.3	5.54374334171787	8.32267434593123
54	5.4	6.34692872869034	7.72764480155351
55	5.5	7.08669770196696	7.05540318464406
56	5.6	7.75565873434559	6.31266631140932
57	5.7	8.34712778796117	5.50685536360511
58	5.8	8.85519509948978	4.64602173821927
59	5.9	9.27478422880316	3.73876660008534
60	5.99999999999999	9.60170278098206	2.79415494178411
61	6.09999999999999	9.83268429515922	1.82162500695928
62	6.19999999999999	9.96542087808491	0.830893996194054
63	6.29999999999999	9.99858626792691	-0.16813902199105
64	6.39999999999999	9.93184908946754	-1.16549205334749
65	6.49999999999999	9.76587615808734	-2.15119988389088
66	6.59999999999999	9.50232582087026	-3.11541362522735
67	6.69999999999999	9.14383138490048	-4.04849918154536
68	6.79999999999999	8.69397480761484	-4.94113347512978
69	6.89999999999999	8.15725090690746	-5.78439759921288
70	6.99999999999999	7.53902244936329	-6.56986593649549
71	7.09999999999999	6.84546657123682	-7.28969034354877
72	7.19999999999999	6.08351305442959	-7.93667857239178
73	7.29999999999999	5.26077508678665	-8.50436613107581
74	7.39999999999999	4.38547319414753	-8.98708087375935
75	7.49999999999999	3.46635310442383	-9.37999967436252
76	7.59999999999999	2.51259836375575	-9.6791966177761
77	7.69999999999999	1.53373857575698	-9.88168222727645
78	7.79999999999999	0.539554179486744	-9.98543333523806
79	7.89999999999999	-0.460021272354385	-9.9894132969739
80	7.99999999999999	-1.45500034337087	-9.89358234379535
81	8.09999999999999	-2.43544152630802	-9.69889798550396
82	8.19999999999999	-3.39154859157393	-9.40730544326142
83	8.29999999999999	-4.31376842819551	-9.02171821251595
84	8.39999999999999	-5.19288651099903	-8.54598895616689
85	8.49999999999999	-6.0201189844898	-7.98487100387354
86	8.59999999999999	-6.78720041740384	-7.34397086031999
87	8.69999999999999	-7.48646638642146	-6.62969218781538
88	8.79999999999998	-8.11093005709774	-5.84917182318787
89	8.89999999999998	-8.65435199476798	-5.01020846862876
90	8.99999999999998	-9.11130250741312	-4.12118476907945
91	9.09999999999998	-9.477215897433	-3.19098355491247
92	9.19999999999998	-9.74843608043022	-2.22889908718859
93	9.29999999999998	-9.92225311531633	-1.24454419258884
94	9.39999999999998	-9.99693027766942	-0.247754220915291
95	9.49999999999998	-9.97172141590341	0.751511217672462
96	9.59999999999998	-9.84687841035703	1.7432678123893
97	9.69999999999998	-9.6236486499409	2.7176062572696
98	9.79999999999998	-9.30426257433173	3.66479126858089
99	9.89999999999998	-8.89191138289135	4.57535889428005
100	9.99999999999998	-8.39071515221216	5.44021104701362
*/