/// <summary>
/// Solve the generalized eigenvalue problem in user-defined shift-invert mode.
/// </summary>
public IEigenSolverResult SolveGeneralized(int k, double sigma, ShiftMode mode, Spectrum job = Spectrum.LargestMagnitude)
{
if (!symmetric && !(mode == ShiftMode.None || mode == ShiftMode.Regular))
{
throw new InvalidOperationException("This mode is only available for symmetric eigenvalue problems.");
}
if (!Job.Validate(symmetric, job))
{
throw new ArgumentException("Invalid job for symmetric eigenvalue problem.", "job");
}
if (ArnoldiCount < k)
{
ArnoldiCount = Math.Min(3 * k, A.RowCount);
}
var result = new SpectraResult(k, size, ComputeEigenVectors, symmetric);
var handles = new List <GCHandle>();
var a = GetMatrix(A, handles);
var b = GetMatrix(B, handles);
var e = result.GetEigenvalueStorage(handles);
int conv = 0;
if (symmetric)
{
char m = 'S';
if (mode == ShiftMode.Buckling)
{
m = 'B';
}
else if (mode == ShiftMode.Cayley)
{
m = 'C';
}
conv = NativeMethods.spectra_di_sg_shift(GetJob(job), m, k, ArnoldiCount, Iterations,
Tolerance, sigma, ref a, ref b, ref e);
}
else
{
throw new NotImplementedException("Shift-invert mode only available for symmetric problems.");
}
result.IterationsTaken = e.iterations;
result.ConvergedEigenValues = conv;
result.ErrorCode = e.info;
InteropHelper.Free(handles);
return(result);
}
/// <summary>
/// Solve the generalized eigenvalue problem.
/// </summary>
public override IEigenSolverResult SolveGeneralized(int k, Spectrum job = Spectrum.LargestMagnitude)
{
if (!Job.Validate(symmetric, job))
{
throw new ArgumentException("Invalid job for given eigenvalue problem.", "job");
}
if (ArnoldiCount < k)
{
ArnoldiCount = Math.Min(3 * k, A.RowCount);
}
var result = new SpectraResult(k, size, ComputeEigenVectors, symmetric);
var handles = new List <GCHandle>();
var a = GetMatrix(A, handles);
var b = GetMatrix(B, handles);
var e = result.GetEigenvalueStorage(handles);
int conv = 0;
if (symmetric)
{
conv = NativeMethods.spectra_di_sg(GetJob(job), k, ArnoldiCount,
Iterations, Tolerance, ref a, ref b, ref e);
}
else
{
throw new NotImplementedException();
//conv = NativeMethods.spectra_di_ng(GetJob(job), k, ArnoldiCount,
// Iterations, Tolerance, ref a, ref b, ref e);
}
result.IterationsTaken = e.iterations;
result.ConvergedEigenValues = conv;
result.ErrorCode = e.info;
InteropHelper.Free(handles);
return(result);
}
