Architecture
Passing CPU() or GPU() to the grid constructor determines whether the grid lives on a CPU or GPU.
Ideally a set up or simulation script does not need to be modified to run on a GPU but still we are smoothing out rough edges. Generally the CPU wants Array objects while the GPU wants CuArray objects.
The section on simulation tips includes information that can come handy when running on GPUs.
We would very welcome any suggestions you may have to improve the API and make transitions from CPU to GPU even smoother. Please open an issue with any such suggestions.