 //******************************************************************************
 __global__ 
 void moveParticles(float2 d_partLoc[], float3 d_partVel[],
-                   const float ex[], const float ey[],
                    const unsigned int numParticles,
                    const float mass,
                    const unsigned int NX1, const unsigned int NY1)

   checkForCudaError("Before moveParticles");
   moveParticles<<<numBlocks, blockSize, 0, stream>>>(
      partLoc.getPtr(), partVel.getPtr(),
      ex.getPtr(), ey.getPtr(),
      numParticles, mass, NX1, NY1);
   checkForCudaError("moveParticles");


           const DevMemF &ex, const DevMemF &ey,
           cudaStream_t &stream)
{
   static bool first = true;

   int numThreads;
   dim3 blockSize;
   dim3 numBlocks;
