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STEP/SIMP -  A platform for fine-grained lattice computing.

Edward Bach

STEP/SIMP is a platform for fine-grained lattice computing such as that of cellular automata (CA), lattice gases/partitioned CA (LG/PCA), and pixel-level image processing.  The SIMP programming environment targets the needs of those who desire to quickly write efficient and readable massively-parallel, fine-grained programs at a high level without worrying about the details of the underlying implementation. STEP is an abstract machine interface that provides set of fine-grained lattice computing primitives into which SIMP programs are compiled.

We demonstrate how to program CA and LG/PCA in SIMP.  First, we'll get our feet wet with a simple CA parity rule and then derive a LG/PCA particle diffusion model which yields the continuous diffusion (heat) equation in the limit.

Finally, we'll discuss the philosophy of the STEP computing format vis-a'-vis traditional formats and highlight some implementation aspects and applications.

STEP/SIMP is free, open-source software available at This work is being done under the academic supervision of Tom Toffoli with support from the DOE. This work is not directly related to the research at NISLAB.




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