From 62cac5e34accfa9f79f564b669e6b093276a5dd2 Mon Sep 17 00:00:00 2001
From: Andy Nonaka <AJNonaka@lbl.gov>
Date: Mon, 25 Nov 2024 11:02:08 -0800
Subject: [PATCH] seems to work

---
 .../GMRES/Poisson/AMReX_GMRES_Poisson.H       | 22 +++----------------
 .../LinearSolvers/GMRES/Poisson/main.cpp      |  3 +--
 2 files changed, 4 insertions(+), 21 deletions(-)

diff --git a/ExampleCodes/LinearSolvers/GMRES/Poisson/AMReX_GMRES_Poisson.H b/ExampleCodes/LinearSolvers/GMRES/Poisson/AMReX_GMRES_Poisson.H
index 08bb4f7d..65f16501 100644
--- a/ExampleCodes/LinearSolvers/GMRES/Poisson/AMReX_GMRES_Poisson.H
+++ b/ExampleCodes/LinearSolvers/GMRES/Poisson/AMReX_GMRES_Poisson.H
@@ -101,8 +101,7 @@ auto GMRESPOISSONT<MF>::makeVecLHS () const -> MF
 template <typename MF>
 auto GMRESPOISSONT<MF>::norm2 (MF const& mf) const -> RT
 {
-    auto r = MultiFab::Dot(mf,0,1,0);
-    return std::sqrt(r);
+    return mf.norm2();
 }
 
 template <typename MF>
@@ -177,29 +176,14 @@ void GMRESPOISSONT<MF>::precond (MF& lhs, MF const& rhs) const
     if (m_use_precond) {
 
     } else {
-        LocalCopy(lhs, rhs, 0, 0, nComp(lhs), IntVect(0));
+        MultiFab::Copy(lhs,rhs,0,0,1,0);
     }
 }
 
 template <typename MF>
 void GMRESPOISSONT<MF>::solve (MF& a_sol, MF const& a_rhs, RT a_tol_rel, RT a_tol_abs)
 {
-    /*
-    auto res = makeVecRHS();
-    m_mlmg->apply({&res}, {&a_sol}); // res = L(sol)
-    increment(res, a_rhs, RT(-1)); // res = L(sol) - rhs
-    auto cor = makeVecLHS();
-    m_linop->setDirichletNodesToZero(0,0,res);
-    m_gmres.solve(cor, res, a_tol_rel, a_tol_abs); // L(cor) = res
-    increment(a_sol, cor, RT(-1)); // sol = sol - cor
-    */
-    auto res = makeVecRHS();
-    apply(res,a_sol);
-    increment(res, a_rhs, RT(-1)); // res = L(sol) - rhs
-    auto cor = makeVecLHS();
-    res.FillBoundary(m_geom.periodicity()); // FIXME not sure this is needed
-    m_gmres.solve(cor, res, a_tol_rel, a_tol_abs); // L(cor) = res
-    increment(a_sol, cor, RT(-1)); // sol = sol - cor
+    m_gmres.solve(a_sol, a_rhs, a_tol_rel, a_tol_abs);
 }
 
 using GMRESPOISSON = GMRESPOISSONT<MultiFab>;
diff --git a/ExampleCodes/LinearSolvers/GMRES/Poisson/main.cpp b/ExampleCodes/LinearSolvers/GMRES/Poisson/main.cpp
index 315c7cac..684a042a 100644
--- a/ExampleCodes/LinearSolvers/GMRES/Poisson/main.cpp
+++ b/ExampleCodes/LinearSolvers/GMRES/Poisson/main.cpp
@@ -107,8 +107,7 @@ int main (int argc, char* argv[])
             amrex::Real x = (i+0.5) * dx[0];
             amrex::Real y = (j+0.5) * dx[1];
             amrex::Real z = (k+0.5) * dx[2];
-            amrex::Real rsquared = ((x-0.5)*(x-0.5)+(y-0.5)*(y-0.5)+(z-0.5)*(z-0.5))/0.01;
-            rhs_p(i,j,k) = 1. + std::exp(-rsquared);
+            rhs_p(i,j,k) = sin(2.*M_PI*x) * sin(4.*M_PI*y) * sin(8.*M_PI*z);
         });
     }