comments

1 files changed, 6 insertions, 1 deletions

diff --git a/Source/Particles/PhysicalParticleContainer.cpp b/Source/Particles/PhysicalParticleContainer.cpp
index ca633fc41..f2d3c0d75 100644
--- a/Source/Particles/PhysicalParticleContainer.cpp
+++ b/Source/Particles/PhysicalParticleContainer.cpp
@@ -1319,9 +1319,14 @@ PhysicalParticleContainer::SplitParticles(int lev)
     {
         pti.GetPosition(xp, yp, zp);
 
+        // offset for split particles is computed as a function of cell size
+        // and number of particles per cell, so that a uniform distribution
+        // before splitting results in a uniform distribution after splitting
         const amrex::Vector<int> ppc_nd = plasma_injector->num_particles_per_cell_each_dim;
         const std::array<Real,3>& dx = WarpX::CellSize(lev);
-        amrex::Vector<amrex::Real> split_offset = {dx[0]/2/ppc_nd[0], dx[1]/2/ppc_nd[1], dx[2]/2/ppc_nd[2]};
+        amrex::Vector<amrex::Real> split_offset = {dx[0]/2/ppc_nd[0],
+                                                   dx[1]/2/ppc_nd[1],
+                                                   dx[2]/2/ppc_nd[2]};
     
         // particle Array Of Structs data
         auto& particles = pti.GetArrayOfStructs();