private Vector CreateInterfaceProblemRhs(FetiDPFlexibilityMatrix flexibility,
IFetiDPCoarseProblemSolver coarseProblemSolver, Vector globalFcStar, Vector dr)
{
// rhs = dr - FIrc * inv(KccStar) * fcStar
Vector rhs = coarseProblemSolver.MultiplyInverseCoarseProblemMatrixTimes(globalFcStar);
rhs = flexibility.MultiplyFIrc(rhs);
rhs = dr - rhs;
return(rhs);
}
public void Multiply(IVectorView lhsVector, IVector rhsVector)
{
//TODO: remove casts. I think PCG, LinearTransformation and preconditioners should be generic, bounded by
// IVectorView and IVector
var lhs = (Vector)lhsVector;
var rhs = (Vector)rhsVector;
// rhs = (FIrr + FIrc * inv(KccStar) * FIrc^T) * lhs
rhs.Clear();
flexibility.MultiplyFIrr(lhs, rhs);
Vector temp = flexibility.MultiplyTransposedFIrc(lhs);
temp = coarseProblemSolver.MultiplyInverseCoarseProblemMatrixTimes(temp);
temp = flexibility.MultiplyFIrc(temp);
rhs.AddIntoThis(temp);
}
public (Vector lagrangeMultipliers, Vector cornerDisplacements) SolveInterfaceProblem(FetiDPFlexibilityMatrix flexibility,
IFetiPreconditioner preconditioner, IFetiDPCoarseProblemSolver coarseProblemSolver,
Vector globalFcStar, Vector dr, double globalForcesNorm, SolverLogger logger)
{
int systemOrder = flexibility.Order;
// Matrix, preconditioner & rhs
var pcgMatrix = new InterfaceProblemMatrix(flexibility, coarseProblemSolver);
var pcgPreconditioner = new InterfaceProblemPreconditioner(preconditioner);
Vector pcgRhs = CreateInterfaceProblemRhs(flexibility, coarseProblemSolver, globalFcStar, dr);
// Solve the interface problem using PCG algorithm
var pcgBuilder = new PcgAlgorithm.Builder();
pcgBuilder.MaxIterationsProvider = maxIterationsProvider;
pcgBuilder.ResidualTolerance = pcgConvergenceTolerance;
pcgBuilder.Convergence = pcgConvergenceStrategyFactory.CreateConvergenceStrategy(globalForcesNorm);
PcgAlgorithm pcg = pcgBuilder.Build(); //TODO: perhaps use the pcg from the previous analysis if it has reorthogonalization.
var lagranges = Vector.CreateZero(systemOrder);
IterativeStatistics stats = pcg.Solve(pcgMatrix, pcgPreconditioner, pcgRhs, lagranges, true,
() => Vector.CreateZero(systemOrder));
// Log statistics about PCG execution
if (!stats.HasConverged)
{
throw new IterativeSolverNotConvergedException(FetiDPSolver.name + " did not converge to a solution. PCG"
+ $" algorithm run for {stats.NumIterationsRequired} iterations and the residual norm ratio was"
+ $" {stats.ResidualNormRatioEstimation}");
}
logger.LogIterativeAlgorithm(stats.NumIterationsRequired, stats.ResidualNormRatioEstimation);
// Calculate corner displacements: uc = inv(KccStar) * (fcStar + FIrc^T * lagranges)
Vector uc = flexibility.MultiplyTransposedFIrc(lagranges);
uc.AddIntoThis(globalFcStar);
uc = coarseProblemSolver.MultiplyInverseCoarseProblemMatrixTimes(uc);
return(lagranges, uc);
}