Result <LoadIncrementalState> GetCorrection(LoadState state, LoadIncrementalState prediction, StructureInfo info)
{
ILinearSolver stiffnessMatrix = info.Stiffness(state.Displacement);
Vector <double> dut = stiffnessMatrix.Solve(info.ReferenceLoad);
Vector <double> reaction = info.Reaction(state.Displacement);
Vector <double> equilibrium = info.InitialLoad + state.Lambda * info.ReferenceLoad - reaction;
Vector <double> dur = stiffnessMatrix.Solve(equilibrium);
Result <LoadIncrementalState> incrementalStateResult = Scheme.Correct(state, prediction, info, dut, dur);
return(incrementalStateResult);
}
internal LoadIncrementalState Predict(LoadState state, double initialStiffness, StructureInfo info)
{
Vector<double> equilibrium = info.InitialLoad + state.Lambda * info.ReferenceLoad - info.Reaction(state.Displacement);
ILinearSolver mK = info.Stiffness(state.Displacement);
Vector<double> Dvt = mK.Solve(info.ReferenceLoad);
Vector<double> Dvr = mK.Solve(equilibrium);
double bergam = GetBergamParameter(initialStiffness, Dvt, info);
double DLambda = Scheme.Predict(Dvt, info.ReferenceLoad) * Math.Sign(bergam);
Vector<double> Dv = DLambda * Dvt + Dvr;
return new LoadIncrementalState(DLambda, Dv);
}
