Pros And Cons Of Each Tool

Which tool is the best depends' on a number of factors: the nature and complexity of the problem, the numher of actions resulting from the deci­ sions, and the ease of use. In reviewing the henefits and limitations of each tool, we come to the following conclusions:

1. The primaty strengh of the DFD is its ability to represent data flows. It may he used at high 01" low levels of analysis and provides good system documentation. However, the tool only weakly shows input and output detail. The user often finds it confusing initially.

2 The data dictionary helps the analyst simplifY the structure for meeting the data requirements of the system. It may be used at high or low levels of analysis, but it does not provide functional details, and it is not acceptable to many nontechnical users.

3. Structured English is best used when the problem requires sequences of actions with decisions.
4. Decision trees are used to verifY logic and in problems that involve a few complex decisions resulting in' a limited number of actions.
5. Decision trees and decision tables are best suited for dealing with complex branching routines such as calculating discounts or sales commissions or inventory control procedures.

Given the pros and cons of structured tools, the analyst should be trained in the use of various tools for analysis and design. He/she should use decision tables and structured English to get to the heart of complex problems. A decision table is perhaps the most useful tool for communicating problem details to the user.

The major contribution of structured analysis to the system develop­ ment life cycle is producing a definable and measurable document-the structured specification. Other benefits include increased user involvement, improved communication between user and designer, reduction of total personnel time, and fewer "kinks" during detailed design and implementa­ tion. The only drawback is increased analyst and user time in the process. Overall the benefits oUtweigh the drawbacks, which make structured analy­ sis tools viable alternatives in system development