Software Engineering

10.2.1 
Functional component
A functional component represents a complex task the software product must per-
form. A functional component is activated when control is transferred to the com-
ponent for execution. Every function transforms one or more data items, in the form 
of an input or global or local variables, into an output data item or processed varia-
ble. Functional complexity is apparent when any of the following conditions exists:
●
  A function involves several data transformation actions and at least one action 
has no clear, uncomplicated solution.
●
  A function involves distinguishable conditional responses.
●
  A function involves multiple interfaces with other functions or external systems, 
users, or other software applications, such as databases.
Functional complexity compels the solution to be further decomposed into less 
complex functional components. Decomposition requires that a functional component 

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