Comments: make AB linear solver convention match documentation

Docs/sphinx_documentation/source/LinearSolvers.rst

@@ -693,7 +693,7 @@ viscous term `divtau` explicitly:
    // Note we call LPInfo().setMaxCoarseningLevel(0) because we are only applying the operator,
    //      not doing an implicit solve
    //
-   //       (alpha * a - beta * (del dot b grad)) sol
+   //       (A * alpha - B * (del dot beta grad)) sol
    //
    // LPInfo                       info;
    MLEBTensorOp ebtensorop(geom, grids, dmap, LPInfo().setMaxCoarseningLevel(0),

Src/LinearSolvers/MLMG/AMReX_MLABecLaplacian.H

@@ -7,8 +7,7 @@
 
 namespace amrex {
 
-// (alpha * a - beta * (del dot b grad)) phi
-
+// (A * alpha - B * (del dot beta grad)) phi
 template <typename MF>
 class MLABecLaplacianT
     : public MLCellABecLapT<MF>

Src/LinearSolvers/MLMG/AMReX_MLEBABecLap.H

@@ -9,8 +9,7 @@
 
 namespace amrex {
 
-// (alpha * a - beta * (del dot b grad)) phi
-
+// (A * alpha - B * (del dot beta grad)) phi
 class MLEBABecLap
     : public MLCellABecLap
 {

Src/LinearSolvers/MLMG/AMReX_MLEBTensorOp.H

@@ -9,20 +9,19 @@ namespace amrex {
 // Tensor solver for high Reynolds flows with small gradient in viscosity.
 // The system it solves is
 //
-//   alpha a v - beta div dot tau = rhs
+//   A alpha v - B div dot tau = rhs
 //
 // where tau = eta [grad v + (grad v)^T] +  (kappa-(2/3)eta) (div v) I.
 // Here eta and kappa are shear and bulk viscosity, and I is identity tensor.
 //
-// The user needs to provide `a` by `setACoeffs`, eta by `setShearViscosity`,
-// and kappa by `setBulkViscosity`.  If `setBulkViscosity` is not called,
-// kappa is set to zero.  The user must also call `setEBShearViscosity` to set
+// The user needs to provide `alpha` by `setACoeffs`, `eta` by `setShearViscosity`,
+// and `kappa` by `setBulkViscosity`.  If `setBulkViscosity` is not called,
+// `kappa` is set to zero.  The user must also call `setEBShearViscosity` to set
 // viscosity on EB.  Optionally, `setEBBulkViscosity` can be used to set
 // bulk viscosity on EB.
 //
-// The scalars alpha and beta can be set with `setScalar(Real, Real)`.  If
+// The scalars `A` and `B` can be set with `setScalar(Real, Real)`.  If
 // they are not set, their default value is 1.
-
 class MLEBTensorOp
     : public MLEBABecLap
 {

Src/LinearSolvers/MLMG/AMReX_MLMG.H

@@ -57,7 +57,7 @@ public:
                           Location a_loc = Location::FaceCenter);
 
     /**
-    * \brief For ``(alpha * a - beta * (del dot b grad)) phi = rhs``, flux means ``-b grad phi``
+    * \brief For ``(A * alpha - B * (del dot beta grad)) phi = rhs``, flux means ``-beta grad phi``
     */
     template <typename AMF>
     void getFluxes (const Vector<Array<AMF*,AMREX_SPACEDIM> >& a_flux,

Src/LinearSolvers/MLMG/AMReX_MLNodeABecLaplacian.H

@@ -6,9 +6,8 @@
 
 namespace amrex {
 
-// (alpha * a - beta * (del dot b grad)) phi = rhs
-// a, phi and rhs are nodal. b is cell-centered.
-
+// (A * alpha - B * (del dot beta grad)) phi = rhs
+// alpha, phi and rhs are nodal. beta is cell-centered.
 class MLNodeABecLaplacian
     : public MLNodeLinOp
 {

Src/LinearSolvers/MLMG/AMReX_MLTensorOp.H

@@ -10,18 +10,17 @@ namespace amrex {
 // Tensor solver for high Reynolds flows with small gradient in viscosity.
 // The system it solves is
 //
-//   alpha a v - beta div dot tau = rhs
+//   A alpha v - B div dot tau = rhs
 //
 // where tau = eta [grad v + (grad v)^T] +  (kappa-(2/3)eta) (div v) I.
 // Here eta and kappa are shear and bulk viscosity, and I is identity tensor.
 //
-// The user needs to provide `a` by `setACoeffs`, eta by `setShearViscosity`,
-// and kappa by `setBulkViscosity`.  If `setBulkViscosity` is not called,
-// kappa is set to zero.
+// The user needs to provide `alpha` by `setACoeffs`, `eta` by `setShearViscosity`,
+// and `kappa` by `setBulkViscosity`.  If `setBulkViscosity` is not called,
+// `kappa` is set to zero.
 //
-// The scalars alpha and beta can be set with `setScalar(Real, Real)`.  If
+// The scalars `A` and `B` can be set with `setScalar(Real, Real)`.  If
 // they are not set, their default value is 1.
-
 class MLTensorOp
     : public MLABecLaplacian
 {

Tests/LinearSolvers/ABecLaplacian_F/README

@@ -1,18 +1,18 @@
 This tutorial demonstrates how to solve the linear system in a
 canonical ABecLaplacian form
 
-    alpha * a * phi - beta * del dot (b grad phi) = rhs.
+    A * alpha * phi - B * del dot (beta grad phi) = rhs.
 
-Here phi is the unknown in a cell-centered MultiFab, alpha and beta
-are scalar constants, a is a cell-centered MultiFab, and b lives on
+Here phi is the unknown in a cell-centered MultiFab, A and B
+are scalar constants, alpha is a cell-centered MultiFab, and beta lives on
 cell faces and is thus represented by D face based MultiFabs, where D
 is the number of spatial dimensions.  The right-hand side, rhs, is
 also cell-centered.  A more specialized version of the ABecLaplacian
 form is Poisson's equation.  This tutorial is written with AMReX's
 Fortran interfaces.
 
 After the solution is obtained, one can also ask for grad phi, or flux
-(defined as -b grad phi).  Note that they live on cell faces.  This
+(defined as -beta grad phi).  Note that they live on cell faces.  This
 step is not performed in this tutorial.  However, one can look at
 `amrex/Src/F_Interfaces/LinearSolvers/AMReX_multigrid_mod.F90` for the
 interface of `get_grad_solution` and `get_fluxes`.