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+This is a very small program for me to pre-compute potential file for ARBD simulation.
+This program generates corresponding potential Dx file when a density Dx file and the potential type is given.
+The supported potential type incudes 12-6 Lennard Jones, Debye-Huckel potential and tabulated potential.
+I partially realize the structure of C++ class structure and late-binding using C function pointer and preprocessing. 
+You have to install fftw3 in order to successfully compile the code.
+I also provide some small tool to manipulate the Dx file such as mult_grid (multiply a grid by a constant), slice_grid (slice outside voxels), sub_grid (subtract two grid values),
+sum_grid (sum two grids).
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