Add solveAgainLaplacian() for multiple RHS solve with same matrix

Add solveAgainLaplacian() for multiple RHS solve with same matrix

src/maths/solvers/LaplacianPetsc.cpp

@@ -37,8 +37,6 @@ void LaplacianPetsc::zeroMatrix()
 
 double LaplacianPetsc::solveLaplacian()
 {
-  PetscInt nbIteration;
-  PetscReal norm;
   PetscBool assembled;
 
   if (!MatAssembled(_LaplacianMatrix,&assembled)) {
@@ -46,8 +44,6 @@ double LaplacianPetsc::solveLaplacian()
     MatAssemblyEnd(_LaplacianMatrix, MAT_FINAL_ASSEMBLY);
   }
 
-  VecAssemblyBegin(_RHS);
-  VecAssemblyEnd(_RHS);
   VecDuplicate(_RHS, &_dum);
 
   KSPSetOperators(_ksp, _LaplacianMatrix, _LaplacianMatrix);
@@ -62,6 +58,18 @@ double LaplacianPetsc::solveLaplacian()
       MatSetNullSpace(_LaplacianMatrix, _nullsp);
     }
   }
+
+  return LaplacianPetsc::solveAgainLaplacian();
+}
+
+double LaplacianPetsc::solveAgainLaplacian()
+{
+  PetscInt nbIteration;
+  PetscReal norm;
+
+  VecAssemblyBegin(_RHS);
+  VecAssemblyEnd(_RHS);
+
   KSPSolve(_ksp, _RHS, _dum);
   KSPGetIterationNumber(_ksp, &nbIteration);
   KSPGetResidualNorm(_ksp, &norm);