Optimal Algorithms of Event-Driven Re-evaluation of Boolean Functions
In many real-time applications, such as distributed logic control systems, response time is crucial. The response is generated by computation of Boolean functions. In this paper event-driven method of recomputations is suggested to get rid of computation overheads and provide the response in optimal time. New type of decision diagrams called Index Decision Diagrams (IDD for short) is introduced to facilitate such computations. Using IDD the computation of the function is performed in time, linear to the number of non-zero elements in the argument vector. Event-driven recomputation consists of two parts: online recomputation which is proven to have running time linear to the number of changed arguments, and precomputation which prepares the model for the former part in a fixed state of the arguments.
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