S-layer-PNP-cpp multiscale electro-diffusion reaction transport model How to compile? Mac clang++ -Ofast -o pnp3d cpp_pnp3d.cpp Linux (with Intel compilers) icc -Ofast -o pnp3d cpp_pnp3d.cpp Matlab (MEX) mex CXXFLAGS='-Ofast' mex_pnp3d.cpp