MFEM  v4.3.0 Finite element discretization library
ortho_solver.cpp
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1 // Copyright (c) 2010-2021, Lawrence Livermore National Security, LLC. Produced
3 // LICENSE and NOTICE for details. LLNL-CODE-806117.
4 //
5 // This file is part of the MFEM library. For more information and source code
6 // availability visit https://mfem.org.
7 //
8 // MFEM is free software; you can redistribute it and/or modify it under the
9 // terms of the BSD-3 license. We welcome feedback and contributions, see file
10 // CONTRIBUTING.md for details.
11
12 #include "ortho_solver.hpp"
13
14 using namespace mfem;
15 using namespace navier;
16
17 OrthoSolver::OrthoSolver(MPI_Comm mycomm_) : Solver(0, true),
18  mycomm(mycomm_) {}
19
21 {
22  oper = &op;
23 }
24
25 void OrthoSolver::Mult(const Vector &b, Vector &x) const
26 {
27  // Orthogonalize input
28  Orthogonalize(b, b_ortho);
29
30  // Apply operator
31  oper->Mult(b_ortho, x);
32
33  // Orthogonalize output
34  Orthogonalize(x, x);
35 }
36
37 void OrthoSolver::Orthogonalize(const Vector &v, Vector &v_ortho) const
38 {
39  double loc_sum = v.Sum();
40  double global_sum = 0.0;
41  int loc_size = v.Size();
42  int global_size = 0;
43
44  MPI_Allreduce(&loc_sum, &global_sum, 1, MPI_DOUBLE, MPI_SUM, mycomm);
45  MPI_Allreduce(&loc_size, &global_size, 1, MPI_INT, MPI_SUM, mycomm);
46
47  double ratio = global_sum / static_cast<double>(global_size);
48  v_ortho.SetSize(v.Size());
50  v_ortho.HostWrite();
51  for (int i = 0; i < v_ortho.Size(); ++i)
52  {
53  v_ortho(i) = v(i) - ratio;
54  }
55 }
void SetSize(int s)
Resize the vector to size s.
Definition: vector.hpp:513
virtual double * HostWrite()
Shortcut for mfem::Write(vec.GetMemory(), vec.Size(), false).
Definition: vector.hpp:438
int Size() const
Returns the size of the vector.
Definition: vector.hpp:190
virtual void Mult(const Vector &x, Vector &y) const =0
Operator application: y=A(x).
virtual void SetOperator(const Operator &op)
Set/update the solver for the given operator.
double b
Definition: lissajous.cpp:42
OrthoSolver(MPI_Comm mycomm_)
virtual const double * HostRead() const