Many Boolean functions have short representations by OBDDs (ordered binary decision diagrams) if appropriate variable orderings are used. For tree-like circuits, which may contain EXOR-gates, it is proved that some depth rst traversal leads to an optimal variable ordering. Moreover, an optimal variable ordering and the resulting OBDD can be computed in time linear in the number of variables and...

The paper presents a family of new expansions of Boolean functions called Function-driven Linearly Independent (fLI) expansions. On the basis of this expansion a new kind of a canonical representation of Boolean functions is constructed: Function-driven Linearly Independent Binary Decision Diagrams (fLIBDDs). They generalize both Function-driven Shannon Binary Decision Diagrams (fShBDDs) and Li...

A widely accepted opinion is that, under a certain ordering restriction, the class of Reduced Ordered Binary Decision Diagrams (ROBDDs) is closed under composition. However, in this paper we show that this is not correct. We formulate necessary and sufficient conditions for the composition of two ROBDDs to result in a non-reduced OBDD. Ignoring these conditions may lead to an incorrect conclusi...

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| We present methods for the construction of small Ordered Kronecker Functional Decision Diagrams (OKFDDs). OKFDDs are a generalization of Ordered Binary Decision Diagrams (OBDDs) and Ordered Functional Decision Diagrams (OFDDs) as well. Starting with an upper bound for the size of an OKFDD representing a tree-like circuit we develope diierent heuristics to nd good variable orderings and decomp...

This paper introduces design methods for numeric function generators (NFGs) using decision diagrams. NFGs are hardware accelerators to compute values of numeric functions such as trigonometric, logarithmic, square root, and reciprocal functions. Most existing design methods for NFGs are intended only for a specific class of numeric functions. However, by using decision diagrams for discrete fun...