External Memoization Worksheet - Maple Help

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External Memoization Using Modules

This worksheet demonstrates a technique for building robust memoized procedures using modules and other techniques. This worksheet is referenced in the help topic on efficiency hints, and goes into further detail about the caching and memoization techniques mentioned there.

Memoization of a procedure is a process by which previously computed values are stored somewhere and, whenever a computation is to be repeated, the stored valued is looked up and returned instead of repeating the entire (typically expensive) computation.

Maple already provides automatic memoization by means of the "remember" option that may be specified for procedures. A procedure with option remember has, as part of its internal data structure, a table in which previously computed values are stored. Whenever the procedure is called, Maple examines the remember table (if one exists) to determine whether the procedure has been called before with the same arguments and therefore has a stored value. If a stored value is found, then it is returned; otherwise, the computation is performed normally, and the computed value is stored in the remember table of the procedure.

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