public void Q2Test()
{
var a = new[] { 1d, 2, 3 };
Func <double, double> q = x =>
{
var sum = 0d;
var r = a.Length;
for (int k = 0; k < a.Length; k++)
{
sum += a[k] * Pow(x, r - k - 1) / fact(r - k - 1);
}
return(sum);
};
var solver = new OdeSolver(x => x, a, a);
var qCoeffs = Range(0, 3).Select(solver.QCoeffs).ToArray();
var Laguerre = Range(0, 3).Select(mathlib.Polynomials.Laguerre.Get).ToArray();
Func <double, double> qLaguerreExpansion = x =>
{
var sum = 0d;
for (int k = 0; k < qCoeffs.Length; k++)
{
sum += qCoeffs[k] * Laguerre[k](x);
}
return(sum);
};
var t = 0d;
while (t < 100)
{
Assert.That(q(t), Is.EqualTo(qLaguerreExpansion(t)).Within(0.0001));
t += 0.1;
}
}
public void QTest()
{
var solver = new OdeSolver(x => x, new[] { 1d, 2, 3 }, new[] { 1d, 2, 3 });
// Q[0] should be equal to sum of coeffs a_i, i=0, 1,..., r-1
Assert.AreEqual(1 + 2 + 3, solver.QCoeffs(0));
}
public static void Main()
{
Console.WriteLine("A) Refer to plot.svg, here u=-u'' is solved and the expected result is sin and cos");
double a = 0;
vector ya = new vector(0, 1);
double b = 2.25 * Math.PI;
double h = 0.1, acc = 1e-3, eps = 1e-3;
var data = OdeSolver.Driver(F, a, ya, b, h, acc, eps, 1000);
File.WriteAllLines("Plot.txt", data.Xs
.Select((x, i) => $"{x} {data.Ys[i][0]} {data.Ys[i][1]}"));
a = 0;
double r0 = 0;
double i0 = 700;
double population = 5500000;
double s0 = population - r0 - i0;
ya = new vector(s0, i0, r0);
b = 120;
h = 0.1;
acc = 1e-3;
eps = 1e-3;
Console.WriteLine("B) SIR modelled with parameters fitting for denmark, refer to plot2.svg");
data = OdeSolver.Driver(sir(population, 8, 3), a, ya, b, h, acc, eps, 1000);
data.Ys[1].print();
File.WriteAllLines("Plot2.txt", data.Xs
.Select((x, i) => $"{x} {data.Ys[i][0]} {data.Ys[i][1]} {data.Ys[i][2]}"));
}
static void RunDLSODE(int numberOfEquations, SolutionMethod solutionMethod, CorrectorIteratorMethod iteratorMethod)
{
Console.WriteLine("Calling DLSODE...");
SolverParams getChordWithDiagonalJacobianSolver() =>
new(new ChordWithDiagonalJacobianSolver(numberOfEquations, solutionMethod),
GetInitialValues(numberOfEquations))
{
StartTime = StartTime,
EndTime = EndTime,
};
SolverParams getFunctionalSolver() =>
new(new FunctionalSolver(numberOfEquations, solutionMethod),
GetInitialValues(numberOfEquations))
{
StartTime = StartTime,
EndTime = EndTime,
};
SolverParams throwNotSupported() =>
throw new NotSupportedException($"Iterator method: {iteratorMethod} is not supported.");
var solverParam = iteratorMethod.Switch(
onFunctional: getFunctionalSolver,
onChordWithUserJacobian: throwNotSupported,
onChordWithGeneratedJacobian: throwNotSupported,
onChordWithDiagonalJacobian: getChordWithDiagonalJacobianSolver,
onChordWithBandedUserJacobian: throwNotSupported,
onChordWithBandedGeneratedJacobian: throwNotSupported);
SolverResult solverResult;
var sw = new Stopwatch();
sw.Start();
unsafe
{
solverResult = OdeSolver.Run(solverParam, FImpl2);
}
var elapsed = sw.Elapsed;
OutputResults(solverResult, elapsed);
}
private void Button3_Click(object sender, EventArgs e)
{
functions.Clear();
startValue.Clear();
span = new double[2];
foreach (DataGridViewRow row in dataGridView1.Rows)
{
row.Selected = false;
if (row.Cells[0].Value != null)
{
functions.Add(row.Cells[0].Value.ToString());
}
else
{
row.DefaultCellStyle.BackColor = Color.FromArgb(255, 255, 0, 0);
}
}
foreach (DataGridViewRow row in dataGridView2.Rows)
{
row.Selected = false;
if (row.Cells[0].Value != null)
{
startValue.Add(Convert.ToDouble(row.Cells[0].Value));
}
else
{
row.DefaultCellStyle.BackColor = Color.FromArgb(255, 255, 0, 0);
}
}
dataGridView3.Rows[0].Cells[0].Selected = false;
dataGridView3.Rows[0].Cells[1].Selected = false;
if (dataGridView3.Rows[0].Cells[0].Value != null && dataGridView3.Rows[0].Cells[1].Value != null)
{
if (Convert.ToDouble(dataGridView3.Rows[0].Cells[0].Value) < Convert.ToDouble(dataGridView3.Rows[0].Cells[1].Value))
{
span[0] = Convert.ToDouble(dataGridView3.Rows[0].Cells[0].Value);
span[1] = Convert.ToDouble(dataGridView3.Rows[0].Cells[1].Value);
var solver = new OdeSolver();
var solution = solver.Ode45(functions.ToArray(), span[0], span[1], startValue.ToArray());
List <Function> result = new List <Function>();
foreach (Function f in solver.Ode45(functions.ToArray(), span[0], span[1], startValue.ToArray()).Functions)
{
result.Add(f);
}
for (int i = 0; i < result.Count; i++)
{
cartesianChart1.Series.Add(new LineSeries
{
Title = "f " + i.ToString() + " =",
Values = new ChartValues <ObservablePoint>(),
LineSmoothness = 0,
PointGeometry = null
});
for (int j = 0; j < result[i].Points.Length; j++)
{
cartesianChart1.Series.Last().Values.Add(new ObservablePoint(result[i].Points[j].X, result[i].Points[j].Y));
}
}
}
else
{
MessageBox.Show("Enter a < b", "Uncorrect span data");
}
}
else
{
dataGridView3.Rows[0].DefaultCellStyle.BackColor = Color.FromArgb(255, 255, 0, 0);
}
}
public void HCoeffsTest()
{
var solver = new OdeSolver(t => Pow(t, 3), new [] { 1d }, new [] { 1d });
var h = Range(0, 5).Select(solver.HCoeffs).ToArray();
}
public static int BinomsProductSum(int s, int k)
{
return(OdeSolver.BinomsProductSum(s, k));
}
