public void Solve(int index)
{
// get base data
var modelBase = new ModelBase();
Freq = (Frequency[index + 1] + Frequency[index]) / 2.0;
dFreq = Frequency[index + 1] - Frequency[index];
__kFT = new double[NTemp];
for (int k = 0; k < NTemp; k++)
{
__kFT[k] = KFT[index, k];
}
// initialization
double dPhi = PI / __nPhi,
dTheta = PI / 2.0 / __nTheta;
double __sPhi = dPhi / 2.0,
__sTheta = dTheta / 2.0;
double dz = 1.0 / __nZ;
Z = new double[__nZ + 1];
Up = new double[__nZ + 1];
U = new double[__nZ + 1];
K = new double[__nZ + 1];
// main
for (int iz = 0; iz <= __nZ; iz++)
{
double z = iz * dz;
Z[iz] = z;
double tf = GetTemperature(z, T0, M);
Up[iz] = __Up(tf, Freq, dFreq);
K[iz] = Interp.Lerp(tf, Temperature, __kFT);
U[iz] = 0.0;
for (int i = 0; i < __nPhi; i++)
{
double phi = __sPhi + dPhi * i;
for (int j = 0; j < __nTheta; j++)
{
double theta = __sTheta + dTheta * j;
// Calculate length of ray [S0, S]
double D = z * Math.Cos(phi) + Math.Sqrt(1.0 - z * z * Math.Sin(phi) * Math.Sin(phi));
double S = Radius * D / Math.Sin(theta);
// Calculate integral of (k * Ip * exp(-|kdy) * d(x)
double result = 0.0;
// 1. Choose how many points we need
int Nj = (int)(1.0 / Math.Sin(theta)) + 1;
// 2. Initialize
double[] kj = new double[Nj + 1];
double[] IP = new double[Nj + 1];
double dS = S / Nj;
// 3. Collect all data we need
for (int jd = 0; jd <= Nj; jd++)
{
double posZ = D * (1.0 - (double)jd / Nj);
double curZ = Math.Sqrt(z * z + posZ * posZ - 2.0 * posZ * z * Math.Cos(phi));
double temp = GetTemperature(curZ, T0, M);
IP[jd] = __Ip(temp, Freq, dFreq);
kj[jd] = Interp.Lerp(temp, Temperature, __kFT);
}
// 4. And now calculate our main stuff
for (int jd = 0; jd <= Nj; jd++)
{
// 4.1 the sub-integral
double sum = 0.0;
for (int jx = jd; jx <= Nj; jx++)
{
sum += kj[jx];
}
sum *= dS;
// 4.2 Result
result += kj[jd] * IP[jd] * Math.Exp(-sum);
}
kj = null;
IP = null;
// 5. Final
U[iz] += result * dS * Math.Sin(theta);
}
}
U[iz] *= 4.0 * dTheta * dPhi;
}
DivF = new double[__nZ + 1];
for (int iz = 0; iz <= __nZ; iz++)
{
DivF[iz] = Ch * K[iz] * (Up[iz] - U[iz]);
}
}
/// <summary>
/// Main solution U(z), Up(z)
/// </summary>
/// <param name="index"></param>
public void Solve(int index)
{
// get base data
var modelBase = new ModelBase();
Freq = (Frequency[index + 1] + Frequency[index]) / 2.0;
dFreq = Frequency[index + 1] - Frequency[index];
__kFT = new double[NTemp];
for (int k = 0; k < NTemp; k++)
{
__kFT[k] = KFT[index, k];
}
// initialization
double dPhi = PI / __nPhi,
dTheta = PI / 2.0 / __nTheta;
double __sPhi = dPhi / 2.0,
__sTheta = dTheta / 2.0;
double dz = 1.0 / __nZ;
Z = new double[__nZ + 1];
Up = new double[__nZ + 1];
U = new double[__nZ + 1];
K = new double[__nZ + 1];
Tau = 0.0;
// main
for (int iz = 0; iz <= __nZ; iz++)
{
double z = iz * dz;
Z[iz] = z;
double tf = GetTemperature(Z[iz], T0, M);
Up[iz] = __Up(tf, Freq, dFreq);
K[iz] = Interp.Lerp(tf, Temperature, __kFT);
Tau += K[iz];
U[iz] = 0.0; // correct?
for (int i = 0; i < __nPhi; i++)
{
double phi = __sPhi + dPhi * i;
for (int j = 0; j < __nTheta; j++)
{
double theta = __sTheta + dTheta * j;
// Calculate length of ray [S0, S]
double D = z * Math.Cos(phi) + Math.Sqrt(1.0 - z * z * Math.Sin(phi) * Math.Sin(phi));
double S = Radius * D / Math.Sin(theta);
// I0 = 0.0 correct?
U[iz] += Math.Sin(theta) *
RungeKutta(0.0, S, I0: 0.0, (int)(1.0 / Math.Sin(theta)) + 1, z, phi, theta);
}
}
U[iz] *= 4.0 * dTheta * dPhi;
}
DivF = new double[__nZ + 1];
for (int iz = 0; iz <= __nZ; iz++)
{
DivF[iz] = Ch * K[iz] * (Up[iz] - U[iz]);
}
Tau *= Radius * dz;
}