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)); }