public FocalLengthFit ComputeFocalLengthFit()
{
if (m_FocalLengthFit != null)
return m_FocalLengthFit;
List<DistSolveEntry> entries = new List<DistSolveEntry>();
for (int i = 0; i < m_Pairs.Count; i++)
{
if (!m_Pairs[i].FitInfo.UsedInSolution) continue;
if (m_Pairs[i].FitInfo.ExcludedForHighResidual) continue;
for (int j = 0; j < m_Pairs.Count; j++)
{
if (i == j) continue;
if (!m_Pairs[j].FitInfo.UsedInSolution) continue;
if (m_Pairs[j].FitInfo.ExcludedForHighResidual) continue;
DistSolveEntry entry = new DistSolveEntry();
entry.DX = Math.Abs(m_Pairs[i].x - m_Pairs[j].x);
entry.DY = Math.Abs(m_Pairs[i].y - m_Pairs[j].y);
entry.StarNo1 = m_Pairs[i].StarNo;
entry.StarNo2 = m_Pairs[j].StarNo;
// NOTE: two ways of computing distances - by vx,vy,vz and Elongation()
//entry.DistRadians = Math.Acos(m_Pairs[i].VX * m_Pairs[j].VX + m_Pairs[i].VY * m_Pairs[j].VY + m_Pairs[i].VZ * m_Pairs[j].VZ);
double elong = AngleUtility.Elongation(m_Pairs[i].RADeg, m_Pairs[i].DEDeg, m_Pairs[j].RADeg, m_Pairs[j].DEDeg);
entry.DistRadians = elong * Math.PI / 180.0;
if (entry.DX == 0 || entry.DY == 0) continue;
entries.Add(entry);
}
}
SafeMatrix A = new SafeMatrix(entries.Count, 2);
SafeMatrix X = new SafeMatrix(entries.Count, 1);
int numStars = 0;
foreach (DistSolveEntry entry in entries)
{
A[numStars, 0] = entry.DX * entry.DX;
A[numStars, 1] = entry.DY * entry.DY;
X[numStars, 0] = entry.DistRadians * entry.DistRadians;
numStars++;
}
// Insufficient stars to solve the plate
if (numStars < 3) return null;
SafeMatrix a_T = A.Transpose();
SafeMatrix aa = a_T * A;
SafeMatrix aa_inv = aa.Inverse();
SafeMatrix bx = (aa_inv * a_T) * X;
double a = bx[0, 0];
double b = bx[1, 0];
double residualSum = 0;
int numResiduals = 0;
foreach (DistSolveEntry entry in entries)
{
entry.ResidualRadians = entry.DistRadians - Math.Sqrt(a * entry.DX * entry.DX + b * entry.DY * entry.DY);
entry.ResidualPercent = entry.ResidualRadians * 100.0 / entry.DistRadians;
entry.ResidualArcSec = 3600.0 * entry.ResidualRadians * 180.0 / Math.PI;
numResiduals++;
residualSum += entry.ResidualRadians * entry.ResidualRadians;
}
double variance = Math.Sqrt(residualSum / (numResiduals - 1));
return new FocalLengthFit(a, b, variance, entries);
}
public FocalLengthFit ComputeFocalLengthFit()
{
if (m_FocalLengthFit != null)
{
return(m_FocalLengthFit);
}
List <DistSolveEntry> entries = new List <DistSolveEntry>();
for (int i = 0; i < m_Pairs.Count; i++)
{
if (!m_Pairs[i].FitInfo.UsedInSolution)
{
continue;
}
if (m_Pairs[i].FitInfo.ExcludedForHighResidual)
{
continue;
}
for (int j = 0; j < m_Pairs.Count; j++)
{
if (i == j)
{
continue;
}
if (!m_Pairs[j].FitInfo.UsedInSolution)
{
continue;
}
if (m_Pairs[j].FitInfo.ExcludedForHighResidual)
{
continue;
}
DistSolveEntry entry = new DistSolveEntry();
entry.DX = Math.Abs(m_Pairs[i].x - m_Pairs[j].x);
entry.DY = Math.Abs(m_Pairs[i].y - m_Pairs[j].y);
entry.StarNo1 = m_Pairs[i].StarNo;
entry.StarNo2 = m_Pairs[j].StarNo;
// NOTE: two ways of computing distances - by vx,vy,vz and Elongation()
//entry.DistRadians = Math.Acos(m_Pairs[i].VX * m_Pairs[j].VX + m_Pairs[i].VY * m_Pairs[j].VY + m_Pairs[i].VZ * m_Pairs[j].VZ);
double elong = AngleUtility.Elongation(m_Pairs[i].RADeg, m_Pairs[i].DEDeg, m_Pairs[j].RADeg, m_Pairs[j].DEDeg);
entry.DistRadians = elong * Math.PI / 180.0;
if (entry.DX == 0 || entry.DY == 0)
{
continue;
}
entries.Add(entry);
}
}
SafeMatrix A = new SafeMatrix(entries.Count, 2);
SafeMatrix X = new SafeMatrix(entries.Count, 1);
int numStars = 0;
foreach (DistSolveEntry entry in entries)
{
A[numStars, 0] = entry.DX * entry.DX;
A[numStars, 1] = entry.DY * entry.DY;
X[numStars, 0] = entry.DistRadians * entry.DistRadians;
numStars++;
}
// Insufficient stars to solve the plate
if (numStars < 3)
{
return(null);
}
SafeMatrix a_T = A.Transpose();
SafeMatrix aa = a_T * A;
SafeMatrix aa_inv = aa.Inverse();
SafeMatrix bx = (aa_inv * a_T) * X;
double a = bx[0, 0];
double b = bx[1, 0];
double residualSum = 0;
int numResiduals = 0;
foreach (DistSolveEntry entry in entries)
{
entry.ResidualRadians = entry.DistRadians - Math.Sqrt(a * entry.DX * entry.DX + b * entry.DY * entry.DY);
entry.ResidualPercent = entry.ResidualRadians * 100.0 / entry.DistRadians;
entry.ResidualArcSec = 3600.0 * entry.ResidualRadians * 180.0 / Math.PI;
numResiduals++;
residualSum += entry.ResidualRadians * entry.ResidualRadians;
}
double variance = Math.Sqrt(residualSum / (numResiduals - 1));
return(new FocalLengthFit(a, b, variance, entries));
}