4-day-mbse-with-core9_2018-reva

Decomposition – The Problem

• Decomposition is the reverse of aggregation. We have not defined what properties must be preserved under decomposition. • How do we go from the top down (i.e., what must be true to say that a function is decomposed by a graph of functions)? • Is decomposition unique?

• Remember we use the black box approach • This is where “design” becomes important

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Decomposition – Preservation of Behavior

• As we decompose, we must preserve all observables: • Inputs and outputs • Input/output sequences • Number and conditions for exits • Performance

A function (f 0

) is said to be decomposed by a graph of functions if the graph  describes the function in more detail.

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