private ColumnVector EulerMEthode2(Grid grid, ColumnVector volterra, ColumnVector Z_Brownian)//Not Used !!
{
int Nbstep = 20;
Func <double, double> epsilon = t => Math.Pow(0.235, 2);
var VIXFutures = new ColumnVector(grid.get_timeNmbrStep() / 50);
for (int k = 1; k <= volterra.Count() / 50; k++)
{
int N_k = k * 50;
Grid secondGrid = new Grid(grid.t(N_k), grid.t(N_k) + Delta, Nbstep);
//3- approximate the continuous-time process V^T by the discrete-time version V^T~ defined via the forward Euler scheme
int N_tau = secondGrid.get_timeNmbrStep();
// Volterra V^T
double[] volterraT = new double[N_tau + 1];
volterraT[0] = volterra[N_k - 1];
for (int j = 1; j <= N_tau; j++)
{
double v = 0.0;
double[] v2 = new double[volterra.Count() / 50];
for (int i = 1; i <= N_k; i++)
{
v += (Z_Brownian[i] - Z_Brownian[i - 1]) / Math.Pow((secondGrid.t(j) - grid.t(i - 1)), -H + 0.5);
}
volterraT[j] = (v);
}
double VIX_future_i = VIX_Calculate(epsilon, secondGrid, volterraT);
VIXFutures[k - 1] += VIX_future_i;
}
return(VIXFutures);
}
public Plot(ColumnVector x_i, ColumnVector y_i, ColumnVector y_i2, string title, string xName, string yName, string curveName)
{
InitializeComponent();
GraphPane myPane = zedGraphControl1.GraphPane;
myPane.Title.Text = title;
myPane.XAxis.Title.Text = xName;
myPane.YAxis.Title.Text = yName;
PointPairList VIX_fut_Prices_LogN = new PointPairList();
PointPairList VIX_fut_Prices_LogN2 = new PointPairList();
for (int i = 0; i < x_i.Count(); i++)
{
VIX_fut_Prices_LogN.Add(x_i[i], y_i[i]);
VIX_fut_Prices_LogN2.Add(x_i[i], y_i2[i]);
//VIX_fut_Prices_TrCholesky.Add(x_i[i], model.TruncatedCholeskyBergomi(x_i[i], epsilon_0));
}
LineItem teamACurve = myPane.AddCurve(curveName,
VIX_fut_Prices_LogN, Color.Red, SymbolType.None);
LineItem teamACurve2 = myPane.AddCurve(curveName,
VIX_fut_Prices_LogN2, Color.Blue, SymbolType.None);
zedGraphControl1.AxisChange();
}
public Plot(ColumnVector x_i, ColumnVector y_i, string title, string xName, string yName, string curveName)
{
InitializeComponent();
GraphPane myPane = zedGraphControl1.GraphPane;
myPane.Title.Text = title;
myPane.XAxis.Title.Text = xName;
myPane.YAxis.Title.Text = yName;
PointPairList VIX_fut_Prices_LogN = new PointPairList();
rBergomiVIXfuture model = new rBergomiVIXfuture();
Func <double, double> epsilon_0 = t => Math.Pow(0.235, 2);// *Math.Pow(1 + t, 0.5);
for (int i = 0; i < x_i.Count(); i++)
{
VIX_fut_Prices_LogN.Add(x_i[i], y_i[i]);
//VIX_fut_Prices_TrCholesky.Add(x_i[i], model.TruncatedCholeskyBergomi(x_i[i], epsilon_0));
}
LineItem teamACurve = myPane.AddCurve(curveName,
VIX_fut_Prices_LogN, Color.Red, SymbolType.None);
zedGraphControl1.AxisChange();
}
public Plot(ColumnVector x_i, ColumnVector y_i, ColumnVector y_i2, ColumnVector y_i3)
{
InitializeComponent();
GraphPane myPane = zedGraphControl1.GraphPane;
myPane.Title.Text = "VIX Futures";
myPane.XAxis.Title.Text = "T";
myPane.YAxis.Title.Text = "VIX futures";
PointPairList VIX_fut_Prices_LogN = new PointPairList();
PointPairList VIX_fut_Prices_LogN2 = new PointPairList();
PointPairList VIX_fut_Prices_LogN3 = new PointPairList();
for (int i = 0; i < x_i.Count(); i++)
{
VIX_fut_Prices_LogN.Add(x_i[i], y_i[i]);
VIX_fut_Prices_LogN2.Add(x_i[i], y_i2[i]);
VIX_fut_Prices_LogN3.Add(x_i[i], y_i3[i]);
//VIX_fut_Prices_TrCholesky.Add(x_i[i], model.TruncatedCholeskyBergomi(x_i[i], epsilon_0));
}
LineItem teamACurve = myPane.AddCurve("Log Normal",
VIX_fut_Prices_LogN, Color.Red, SymbolType.None);
LineItem teamACurve2 = myPane.AddCurve("Hybrid + Euler",
VIX_fut_Prices_LogN2, Color.Blue, SymbolType.None);
LineItem teamACurve3 = myPane.AddCurve("Truncated Cholesky",
VIX_fut_Prices_LogN3, Color.Green, SymbolType.None);
zedGraphControl1.AxisChange();
}
static void Main(string[] args)
{
//Ploting results Graph
//Application.EnableVisualStyles();
//Application.SetCompatibleTextRenderingDefault(false);
//Application.Run(new Graph());
rBergomiVIXfuture model = new rBergomiVIXfuture();
Func <double, double> epsilon_0 = t => Math.Pow(0.235, 2);// *Math.Sqrt(1 + t);
double T = 2.0;
//// the Gri t_0 ..... t_{100} = T
int n = 500;
Grid grid = new Grid(0, T, (int)Math.Abs(T * n));
//lognormal
double vixfuture_LogNormal = model.VIXfuture_LogNormal(grid.t(35), epsilon_0);
// //Mc with hybrid Scheme
ColumnVector vixfuture_Hybrid = model.VIXfuture_HybridMethod(T, epsilon_0);
ColumnVector newvixfutures = new ColumnVector(vixfuture_Hybrid.Count());
ColumnVector newvixlognorm = new ColumnVector(vixfuture_Hybrid.Count());
ColumnVector newvixtruncated = new ColumnVector(vixfuture_Hybrid.Count());
ColumnVector ti = new ColumnVector(vixfuture_Hybrid.Count());
int perdiod = 100;
for (int i = 0; i < vixfuture_Hybrid.Count(); i++)
{
int N_i = (i + 1) * perdiod;
ti[i] = grid.t((N_i));
newvixfutures[i] = vixfuture_Hybrid[i];
newvixtruncated[i] = model.VIXfuture_TruncatedChlsky(ti[i], epsilon_0);
newvixlognorm[i] = model.VIXfuture_LogNormal(ti[i], epsilon_0);
}
Application.Run(new Plot(ti, newvixlognorm, newvixfutures, newvixtruncated));
//Application.Run(new Plot(ti, newvixfutures,newvixlognorm, "Volterra Simulation in hybrid Method", "T + Delta ", "V", "volterra process"));
//Application.Run(new Plot(ti, newvixlognorm, "Volterra Simulation in hybrid Method", "T + Delta ", "V", "volterra process"));
// //Mc with trancated Cholesky
double TrancatedMethode_MCstdDeviation;
double vixfuture_trancated = model.VIXfuture_TruncatedChlsky(T, epsilon_0, out TrancatedMethode_MCstdDeviation);
//S&P Option Pricing
VIXOption option = new VIXOption(VIXOption.OptionType.Call, 1.0, 100);
double optionPrice = model.PriceVIXOption(option, epsilon_0, 100);
} //Main
public void simulateFFT(out ColumnVector Z, out ColumnVector volterra)
{
int n_T = grid.get_timeNmbrStep();
//Z_i defined in A.1
Z = new ColumnVector(n_T);
RectangularMatrix Z_k = new RectangularMatrix(2, n_T);
volterra = new ColumnVector(n_T);
//DateTime starttestM = DateTime.Now;
//for (int zz = 1; zz <= 1.0E4; zz++)
//{
// SimulateCorrelated(Z, Z_k);
//}
//TimeSpan timeExecutiontestM = DateTime.Now - starttestM;
SimulateCorrelated(Z, Z_k);//Simulate 3 Correlated Gaussians Z_i; Z_k_{1,i}; Z_k_{2,i} i:= 0, ..., n_T
//Gamma for Convolution
double[] Zdouble = Z.ToArray();
double[] convolution;
DateTime starttest = DateTime.Now;
//for (int zz = 1; zz <= 1.0E4; zz++)
// alglib.convr1d(Gamma.ToArray(), n_T, Z.ToArray(), n_T, out convolution2);
//TimeSpan timeExecutiontest = DateTime.Now - starttest;
alglib.convr1d(Gamma.ToArray(), n_T, Z.ToArray(), n_T, out convolution);
//DateTime starttestM = DateTime.Now;
//for (int zz = 1; zz <= 1.0E5; zz++)
//{
//}
//TimeSpan timeExecutiontestM = DateTime.Now - starttestM;
//var convolutionM = new Double1DConvolution(Z, Gamma.Count());
//DoubleVector convolution = convolutionM.Convolve(Gamma);
for (int i = 1; i <= volterra.Count(); i++)
{
double v = convolution[i - 1];
for (int k = 1; k < Math.Min(i, kappa); k++)
{
v += Z_k[k - 1, i - k];
}
volterra[i - 1] = v;
}
}
public ColumnVector VIXfuture_HybridMethod(double T, Func <double, double> epsilon)
{
//Result
ColumnVector VIXFutures;
//For Exécution Time
DateTime start = DateTime.Now;
//Input:
int kappa = 2;
// the Gri t_0 ..... t_{100} = T
int n = 500;
Grid grid = new Grid(0, T, (int)Math.Abs(T * n));
int n_T = grid.get_timeNmbrStep();
n_tH = Math.Pow(n_T, H - 0.5); //optimizeMC
//The second Grid t_0=T, t_1 ..... t_N = T + Delta
int Nbstep = 20;
//Correlation :
SymmetricMatrix correl = MakeCorrel(n, grid);
SquareMatrix choleskyCorrel = correl.CholeskyDecomposition().SquareRootMatrix();
int period = 100;
VIXFutures = new ColumnVector(grid.get_timeNmbrStep() / period);
//--------------------------------------------------------------------------------------------------------------------------------------------------------------
//-----------------------------------MC----------------------------------------------------------------------------------------------------------------------
//-----------------------------------------------------------------------------------------------------------------------------------------------------------
var MCnbofSimulation = 3.0E4;
HybridScheme hybridscheme = new HybridScheme(choleskyCorrel, grid, kappa, H);
for (int mc = 1; mc <= MCnbofSimulation; mc++)
{
// 1-simulation of volterra Hybrid Scheme
ColumnVector Z;
ColumnVector volterra;
ColumnVector Z_Brownian;
hybridscheme.simulateFFT(out Z, out volterra);
//2 - extract the path of the Brownian motion Z driving the Volterra process
Z_Brownian = ExtractBrownian(kappa, n_T, Z, volterra);
//Grid secondGrid2 = new Grid(grid.t(n_T), grid.t(n_T) + Delta, 20);
//ColumnVector volterraT2 = EulerMEthode(grid, secondGrid2, n_T, volterra, Z_Brownian);
//double VIX_future_i2 = VIX_Calculate(epsilon, secondGrid2, volterraT2);
//VIXFutures[0] += VIX_future_i2;
//DateTime starttestM = DateTime.Now;
//for (int zz = 1; zz <= 1.0E4; zz++)
//{
// hybridscheme.simulateFFT(out Z, out volterra);
//}
//TimeSpan timeExecutiontestM = DateTime.Now - starttestM;
//DateTime starttest = DateTime.Now;
//for (int zz = 1; zz <= 1.0E4; zz++)
//{
// for (int i = 1; i <= volterra.Count() / period; i++)
// {
// int N_i2 = i * period;
// //3- approximate the continuous-time process V^T by the discrete-time version V^T~ defined via the forward Euler scheme
// double[] volterraT2 = EulerMEthode(grid, secondGrid, N_i2, volterra, Z_Brownian);
// //double VIX_future_i2 = VIX_Calculate(epsilon, secondGrid, volterraT2);
// //VIXFutures[i - 1] += VIX_future_i2;
// }
//}
//TimeSpan timeExecutiontest = DateTime.Now - starttest;
for (int i = 1; i <= volterra.Count() / period; i++)
{
int N_i = i * period;
Grid secondGrid = new Grid(grid.t(N_i), grid.t(N_i) + Delta, Nbstep);
//3- approximate the continuous-time process V^T by the discrete-time version V^T~ defined via the forward Euler scheme
double[] volterraT = EulerMEthode(grid, secondGrid, N_i, volterra, Z_Brownian);
double VIX_future_i = VIX_Calculate(epsilon, secondGrid, volterraT);
VIXFutures[i - 1] += VIX_future_i;
}
}// ENd of MC
//MC Mean
for (int i = 0; i < VIXFutures.Count(); i++)
{
VIXFutures[i] /= MCnbofSimulation;
}
TimeSpan timeExecution = DateTime.Now - start;
return(VIXFutures);
}
/// <summary>
///
/// </summary>
/// <param name="pop"></param>
/// <param name="muBest"></param>
/// <param name="muWorst"></param>
public void ReEstimate(RectangularMatrix pop, double muBest, double muWorst)
{
if (pop.ColumnCount != p.Mu)
{
throw new ApplicationException("");
}
int n = p.N;
fitnessHistory[gen % fitnessHistory.Count()] = muBest; // needed for divergence check
ColumnVector oldmean = new ColumnVector(mean.Dimension);
for (int i = 0; i < mean.Dimension; i++)
{
oldmean[i] = mean [i];
}
double[] BDz = new double[n]; // valarray<double>
/* calculate xmean and rgBDz~N(0,C) */
for (int i = 0; i < n; ++i)
{
mean[i] = 0.0;
for (int j = 0; j < pop.ColumnCount; ++j)
{
mean[i] += p.Weights[j] * (pop.Column(j))[i];
}
BDz[i] = Math.Sqrt(p.MuEff) * (mean[i] - oldmean[i]) / sigma;
}
ColumnVector tmp = new ColumnVector(n); // [vector<double>]
/* calculate z := D^(-1) * B^(-1) * rgBDz into rgdTmp */
for (int i = 0; i < n; ++i)
{
double sum = 0.0;
for (int j = 0; j < n; ++j)
{
sum += B[j, i] * BDz[j];
}
tmp[i] = sum / d[i];
}
/* cumulation for sigma (ps) using B*z */
for (int i = 0; i < n; ++i)
{
double sum = 0.0;
for (int j = 0; j < n; ++j)
{
sum += B[i, j] * tmp[j];
}
ps[i] = (1.0 - p.CCumSig) * ps[i] + Math.Sqrt(p.CCumSig * (2.0 - p.CCumSig)) * sum;
}
/* calculate norm(ps)^2 */
double psxps = ps.Sum(x => x * x);
double chiN = Math.Sqrt((double)p.N) * (1.0 - 1.0 / (4.0 * p.N) + 1.0 / (21.0 * p.N * p.N));
/* cumulation for covariance matrix (pc) using B*D*z~N(0,C) */
bool isHsig = Math.Sqrt(psxps) / Math.Sqrt(1.0 - Math.Pow(1.0 - p.CCumSig, 2.0 * gen)) / chiN < 1.5 + 1.0 / (p.N - 0.5);
double hsig = (isHsig) ? 1.0 : 0.0;
//pc = (1.0 - p.ccumcov) * pc + hsig * Math.Sqrt(p.ccumcov * (2.0 - p.ccumcov)) * BDz;
pc = pc.Select(x => x * (1.0 - p.CCumCov)).Zip(BDz.Select(x => x * Math.Sqrt(p.CCumCov * (2.0 - p.CCumCov)) * hsig), (lhs, rhs) => lhs + rhs).ToArray();
/* stop initial phase (MK, this was not reachable in the org code, deleted) */
/* remove momentum in ps, if ps is large and fitness is getting worse */
if (gen >= fitnessHistory.Count())
{
// find direction from muBest and muWorst (muBest == muWorst handled seperately
double direction = (muBest < muWorst) ? -1.0 : 1.0;
int now = gen % fitnessHistory.Count();
int prev = (gen - 1) % fitnessHistory.Count();
int prevprev = (gen - 2) % fitnessHistory.Count();
bool fitnessWorsens = (muBest == muWorst) || // <- increase norm also when population has converged (this deviates from Hansen's scheme)
((direction * fitnessHistory[now] < direction * fitnessHistory[prev])
&&
(direction * fitnessHistory[now] < direction * fitnessHistory[prevprev]));
if (psxps / p.N > 1.5 + 10.0 * Math.Sqrt(2.0 / p.N) && fitnessWorsens)
{
double tfac = Math.Sqrt((1 + Math.Max(0.0, Math.Log(psxps / p.N))) * p.N / psxps);
ps = ps.Select(x => x * tfac).ToArray();
psxps *= tfac * tfac;
}
}
/* update of C */
/* Adapt_C(t); not used anymore */
if (p.CCov != 0.0)
{
//flgEigensysIsUptodate = 0;
/* update covariance matrix */
for (int i = 0; i < n; ++i)
{
for (int j = 0; j <= i; ++j)
{
C[i, j] =
(1 - p.CCov) * C[i, j]
+
p.CCov * (1.0 / p.MuCov) * pc[i] * pc[j]
+
(1 - hsig) * p.CCumCov * (2.0 - p.CCumCov) * C[i, j];
/*C[i][j] = (1 - p.ccov) * C[i][j]
+ sp.ccov * (1./sp.mucov)
* (rgpc[i] * rgpc[j]
+ (1-hsig)*sp.ccumcov*(2.-sp.ccumcov) * C[i][j]); */
for (int k = 0; k < p.Mu; ++k)
{
/* additional rank mu update */
C[i, j] += p.CCov * (1 - 1.0 / p.MuCov) * p.Weights[k]
* ((pop.Column(k))[i] - oldmean[i])
* ((pop.Column(k))[j] - oldmean[j])
/ sigma / sigma;
// * (rgrgx[index[k]][i] - rgxold[i])
// * (rgrgx[index[k]][j] - rgxold[j])
// / sigma / sigma;
}
}
}
}
/* update of sigma */
sigma *= Math.Exp(((Math.Sqrt(psxps) / chiN) - 1.0) / p.Damp);
/* calculate eigensystem, must be done by caller */
//cmaes_UpdateEigensystem(0);
/* treat minimal standard deviations and numeric problems
* Note that in contrast with the original code, some numerical issues are treated *before* we
* go into the eigenvalue calculation */
treatNumericalIssues(muBest, muWorst);
gen++; // increase generation
}