# On the connection between hexagonal and unidirectional rectangular systolic arrays

## Abstract

We define a simple transformation between systolic algorithms with hexagonal and with rectangular processor arrays. Using this transformation we can establish a direct correspondence between two independently developed systolic arrays for solving the algebraic path problem (matrix inversion, shortest paths in a network, transitive closure of a relation). Then we derive a new hexagonal array for solving a certain type of dynamic programming recursion that arises for example in context-free language recognition, in the construction of optimal binary search trees, or in the computation of an optimal sequence of multiplications for the evaluation of an associative product.

In general, the type of transformation used here allows arbitrary systolic arrays to be transformed into unidirectional ones, which are preferable from the points of view of fault tolerance, two-level pipelining, and algorithm partitioning.

## Keywords

Data Flow Transitive Closure Systolic Array Hexagonal Array Rectangular Array## Preview

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## References

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