From d4e0b11bb135ea0bb2abf92c2a22816a3c1b38c3 Mon Sep 17 00:00:00 2001
From: Guido Cossu <guido.cossu@ed.ac.uk>
Date: Wed, 23 Nov 2016 11:46:51 +0000
Subject: [PATCH] Adding few comments

---
 lib/algorithms/iterative/ConjugateGradient.h | 8 +++++---
 tests/hmc/Test_hmc_WilsonFermionGauge.cc     | 3 +++
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/lib/algorithms/iterative/ConjugateGradient.h b/lib/algorithms/iterative/ConjugateGradient.h
index 5ba5cd5d..0c90c5b4 100644
--- a/lib/algorithms/iterative/ConjugateGradient.h
+++ b/lib/algorithms/iterative/ConjugateGradient.h
@@ -60,9 +60,11 @@ class ConjugateGradient : public OperatorFunction<Field> {
                            // Defaults true.
   RealD Tolerance;
   Integer MaxIterations;
+
+  // Reproducibility controls
   bool ReproTest;
-  CG_state CGState;//to check reproducibility by repeating the CG
-  ReproducibilityState<typename Field::vector_object> ReprTest;
+  CG_state CGState; //to check reproducibility by repeating the CG
+  ReproducibilityState<typename Field::vector_object> ReprTest; // for the inner proucts
 
   ConjugateGradient(RealD tol, Integer maxit, bool err_on_no_conv = true,
         bool ReproducibilityTest = false)
@@ -95,7 +97,7 @@ class ConjugateGradient : public OperatorFunction<Field> {
     Linop.HermOpAndNorm(psi, mmp, d, b);
     
     if(!ReprTest.do_check)
-    	ReprTest.reset();
+        ReprTest.reset();
     ReprTest.enable_reprocheck=ReproTest;
 
 
diff --git a/tests/hmc/Test_hmc_WilsonFermionGauge.cc b/tests/hmc/Test_hmc_WilsonFermionGauge.cc
index 351d1e68..84240426 100644
--- a/tests/hmc/Test_hmc_WilsonFermionGauge.cc
+++ b/tests/hmc/Test_hmc_WilsonFermionGauge.cc
@@ -63,6 +63,9 @@ class HmcRunner : public NerscHmcRunner {
     Real mass = -0.77;
     FermionAction FermOp(U, *FGrid, *FrbGrid, mass);
 
+    // To enable the CG reproducibility tests use 
+    // ConjugateGradient<FermionField> CG(1.0e-8, 10000, true, true);
+    // This is the plain version
     ConjugateGradient<FermionField> CG(1.0e-8, 10000);
 
     TwoFlavourPseudoFermionAction<ImplPolicy> Nf2(FermOp, CG, CG);