4 files changed, 43 insertions, 9 deletions
diff --git a/Source/Parallelization/Make.package b/Source/Parallelization/Make.package
index c74583522..7c3c38627 100644
--- a/Source/Parallelization/Make.package
+++ b/Source/Parallelization/Make.package
@@ -2,6 +2,7 @@ CEXE_sources += WarpXComm.cpp
 CEXE_sources += WarpXRegrid.cpp
 CEXE_headers += WarpXSumGuardCells.H
 CEXE_headers += WarpXComm_K.H
+CEXE_headers += WarpXComm.H
 
 INCLUDE_LOCATIONS += $(WARPX_HOME)/Source/Parallelization
 VPATH_LOCATIONS   += $(WARPX_HOME)/Source/Parallelization
diff --git a/Source/Parallelization/WarpXComm.H b/Source/Parallelization/WarpXComm.H
new file mode 100644
index 000000000..81f00088e
--- /dev/null
+++ b/Source/Parallelization/WarpXComm.H
@@ -0,0 +1,33 @@
+#ifndef WARPX_PARALLELIZATION_COMM_H_
+#define WARPX_PARALLELIZATION_COMM_H_
+
+#include <AMReX_MultiFab.H>
+
+/** \brief Fills the values of the current on the coarse patch by
+ *  averaging the values of the current of the fine patch (on the same level).
+ *  Also fills the guards of the coarse patch.
+ *
+ * \param[in]  fine             fine patches to interpolate from
+ * \param[out] coarse           coarse patches to interpolate to
+ * \param[in]  refinement_ratio integer ratio between the two
+ */
+void
+interpolateCurrentFineToCoarse (
+      std::array< amrex::MultiFab const *, 3 > const & fine,
+      std::array< amrex::MultiFab       *, 3 > const & coarse,
+      int const refinement_ratio);
+
+/** \brief Fills the values of the charge density on the coarse patch by
+ *  averaging the values of the charge density of the fine patch (on the same level).
+ *
+ * \param[in]  fine             fine patches to interpolate from
+ * \param[out] coarse           coarse patches to interpolate to
+ * \param[in]  refinement_ratio integer ratio between the two
+ */
+void
+interpolateDensityFineToCoarse (
+     const amrex::MultiFab& fine,
+     amrex::MultiFab& coarse,
+     int const refinement_ratio);
+
+#endif // WARPX_PARALLELIZATION_COMM_H_
diff --git a/Source/Parallelization/WarpXComm.cpp b/Source/Parallelization/WarpXComm.cpp
index 52df3dc25..b61ae4fc7 100644
--- a/Source/Parallelization/WarpXComm.cpp
+++ b/Source/Parallelization/WarpXComm.cpp
@@ -1,14 +1,14 @@
+#include <WarpXComm.H>
 #include <WarpXComm_K.H>
 #include <WarpX.H>
 #include <WarpX_f.H>
 #include <WarpXSumGuardCells.H>
-#include <Parallelization/InterpolateCurrentFineToCoarse.H>
-#include <Parallelization/InterpolateDensityFineToCoarse.H>
+#include <InterpolateCurrentFineToCoarse.H>
+#include <InterpolateDensityFineToCoarse.H>
 
 #include <algorithm>
 #include <cstdlib>
 
-
 using namespace amrex;
 
 void
@@ -503,9 +503,9 @@ WarpX::SyncCurrent ()
 }
 
 void
-WarpX::interpolateCurrentFineToCoarse ( std::array< amrex::MultiFab const *, 3 > const & fine,
-                                        std::array< amrex::MultiFab       *, 3 > const & coarse,
-                                        int const refinement_ratio)
+interpolateCurrentFineToCoarse ( std::array< amrex::MultiFab const *, 3 > const & fine,
+                                 std::array< amrex::MultiFab       *, 3 > const & coarse,
+                                 int const refinement_ratio)
 {
     BL_PROFILE("interpolateCurrentFineToCoarse()");
     BL_ASSERT(refinement_ratio == 2);
@@ -563,7 +563,7 @@ WarpX::SyncRho ()
 }
 
 void
-WarpX::interpolateDensityFineToCoarse (const MultiFab& fine, MultiFab& coarse, int const refinement_ratio)
+interpolateDensityFineToCoarse (const MultiFab& fine, MultiFab& coarse, int const refinement_ratio)
 {
     BL_PROFILE("interpolateDensityFineToCoarse()");
     BL_ASSERT(refinement_ratio == 2);
diff --git a/Source/Parallelization/WarpXRegrid.cpp b/Source/Parallelization/WarpXRegrid.cpp
index 2ae167283..29ccc8f4d 100644
--- a/Source/Parallelization/WarpXRegrid.cpp
+++ b/Source/Parallelization/WarpXRegrid.cpp
@@ -1,4 +1,3 @@
-
 #include <WarpX.H>
 #include <AMReX_BLProfiler.H>
 
@@ -12,7 +11,8 @@ WarpX::LoadBalance ()
 
     AMREX_ALWAYS_ASSERT(costs[0] != nullptr);
 
-    for (int lev = 0; lev <= finestLevel(); ++lev)
+    const int nLevels = finestLevel();
+    for (int lev = 0; lev <= nLevels; ++lev)
     {
         const Real nboxes = costs[lev]->size();
         const Real nprocs = ParallelDescriptor::NProcs();