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diff --git a/Source/FieldSolver/FiniteDifferenceSolver/FiniteDifferenceAlgorithms/FieldAccessorFunctors.H b/Source/FieldSolver/FiniteDifferenceSolver/FiniteDifferenceAlgorithms/FieldAccessorFunctors.H
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+++ b/Source/FieldSolver/FiniteDifferenceSolver/FiniteDifferenceAlgorithms/FieldAccessorFunctors.H
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+#ifndef WARPX_FIELD_ACCESSOR_FUNCTORS_H
+#define WARPX_FIELD_ACCESSOR_FUNCTORS_H
+#include "WarpX.H"
+/**
+ * \brief Functor that returns the division of the source m_field Array4 value
+          by macroparameter, m_parameter value at the respective (i,j,k,ncomp).
+ */
+struct FieldAccessorMacroscopic
+{
+    AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE
+    FieldAccessorMacroscopic ( amrex::Array4<amrex::Real const> const a_field,
+                               amrex::Array4<amrex::Real const> const a_parameter )
+        : m_field(a_field), m_parameter(a_parameter) {}
+
+    /**
+     * \brief return field value at (i,j,k,ncomp) scaled by (1/m_parameters(i,j,k,ncomp))
+     * \param[in] i      index along x of the Array4, m_field and m_parameter.
+     * \param[in] j      index along y of the Array4, m_field and m_parameter.
+     * \param[in] k      index along z of the Array4, m_field and m_parameter.
+     * \param[in] ncomp  index along fourth component of the Array4, containing field-data
+                         to be returned after diving with zero-th component
+                         of m_paramter.
+     *
+     * \return           m_field/m_paramter at (i,j,k,ncomp)
+     */
+    AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE
+    amrex::Real operator() (int const i, int const j,
+                            int const k, int const ncomp) const noexcept
+    {
+        return ( m_field(i, j, k, ncomp)  /  m_parameter(i, j, k, 0) ) ;
+    }
+private:
+    /** Array4 of the source field to be scaled and returned by the operator() */
+    amrex::Array4<amrex::Real const> const m_field;
+    /** Array4 of the macroscopic parameter used to divide m_field in the operator() */
+    amrex::Array4<amrex::Real const> const m_parameter;
+};
+
+
+#endif