From 2e368fc67d18f70f0c94dc6da2f97307c9394011 Mon Sep 17 00:00:00 2001
From: Daniel Diez <ddiez@altair.com>
Date: Tue, 17 Oct 2023 13:06:39 +0200
Subject: [PATCH 1/2] allow using different var for pressure

---
 kratos/linear_solvers/amgcl_ns_solver.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/kratos/linear_solvers/amgcl_ns_solver.h b/kratos/linear_solvers/amgcl_ns_solver.h
index b5c30c2e4940..ea94e46fa7e5 100644
--- a/kratos/linear_solvers/amgcl_ns_solver.h
+++ b/kratos/linear_solvers/amgcl_ns_solver.h
@@ -118,6 +118,7 @@ class AMGCL_NS_Solver : public LinearSolver< TSparseSpaceType,
         //kratos specific settings
         mTol = rParameters["inner_settings"]["solver"]["tol"].GetDouble();
         mVerbosity=rParameters["verbosity"].GetInt();
+        mPressureVarName = rParameters["schur_variable"].GetString();
         mndof = 1; 
 
         //pass settings to amgcl
@@ -403,12 +404,13 @@ class AMGCL_NS_Solver : public LinearSolver< TSparseSpaceType,
         //*****************************
         //compute pressure mask
         if(mp.size() != rA.size1()) mp.resize( rA.size1() );
+        const auto& r_pressure_var = KratosComponents<Variable<double>>::Get(mPressureVarName);
         for (ModelPart::DofsArrayType::iterator it = rDofSet.begin(); it!=rDofSet.end(); it++)
         {
             const unsigned int eq_id = it->EquationId();
             if( eq_id < rA.size1() )
             {
-                mp[eq_id]  = (it->GetVariable().Key() == PRESSURE);
+                mp[eq_id]  = (it->GetVariable().Key() == r_pressure_var);
             }
         }
 
@@ -419,6 +421,7 @@ class AMGCL_NS_Solver : public LinearSolver< TSparseSpaceType,
 
     double mTol;
     int mVerbosity;
+    std::string mPressureVarName;
     int mndof;
     std::vector< char > mp;
 

From 9497725b928e4aff6e227efbbaf17ea3b52bd10d Mon Sep 17 00:00:00 2001
From: Daniel Diez <ddiez@altair.com>
Date: Tue, 17 Oct 2023 14:46:12 +0200
Subject: [PATCH 2/2] using pointer

---
 kratos/linear_solvers/amgcl_ns_solver.h | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/kratos/linear_solvers/amgcl_ns_solver.h b/kratos/linear_solvers/amgcl_ns_solver.h
index ea94e46fa7e5..1c06fe996c08 100644
--- a/kratos/linear_solvers/amgcl_ns_solver.h
+++ b/kratos/linear_solvers/amgcl_ns_solver.h
@@ -28,6 +28,7 @@
 
 // Project includes
 #include "includes/define.h"
+#include "includes/kratos_components.h"
 #include "linear_solvers/iterative_solver.h"
 
 #include <boost/property_tree/json_parser.hpp>
@@ -118,7 +119,8 @@ class AMGCL_NS_Solver : public LinearSolver< TSparseSpaceType,
         //kratos specific settings
         mTol = rParameters["inner_settings"]["solver"]["tol"].GetDouble();
         mVerbosity=rParameters["verbosity"].GetInt();
-        mPressureVarName = rParameters["schur_variable"].GetString();
+        const std::string pressure_var_name = rParameters["schur_variable"].GetString();
+        mpPressureVar = &KratosComponents<Variable<double>>::Get(pressure_var_name);
         mndof = 1; 
 
         //pass settings to amgcl
@@ -404,13 +406,12 @@ class AMGCL_NS_Solver : public LinearSolver< TSparseSpaceType,
         //*****************************
         //compute pressure mask
         if(mp.size() != rA.size1()) mp.resize( rA.size1() );
-        const auto& r_pressure_var = KratosComponents<Variable<double>>::Get(mPressureVarName);
         for (ModelPart::DofsArrayType::iterator it = rDofSet.begin(); it!=rDofSet.end(); it++)
         {
             const unsigned int eq_id = it->EquationId();
             if( eq_id < rA.size1() )
             {
-                mp[eq_id]  = (it->GetVariable().Key() == r_pressure_var);
+                mp[eq_id]  = (it->GetVariable().Key() == *mpPressureVar);
             }
         }
 
@@ -421,7 +422,7 @@ class AMGCL_NS_Solver : public LinearSolver< TSparseSpaceType,
 
     double mTol;
     int mVerbosity;
-    std::string mPressureVarName;
+    const Variable<double>* mpPressureVar = nullptr;
     int mndof;
     std::vector< char > mp;