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The best practice in symbol detail is shown in Table 2.5. Symbol
Best practice suggestions
Input and output
The word INPUT or OUTPUT should be included in the symbol. As the symbol for inputs and outputs is the same, this helps to avoid confusion.
Process
LE
The name of the data to be input or output should be descriptive. Avoid single letter descriptions, such as INPUT A. A description of the process must be included in the process symbol.
Complex processes should be broken down into a series of simple steps, each step being represented by a different processes symbol. A process can have only a single outward flow. If a process had two outward flow lines, which one would be followed?
A decision will have two outward flows. Where more than one option exists, a sequence of decisions should be used.
P
Decision
The condition that will control the flow of execution must be included in the decision symbol.
M
It is crucial to label the outgoing flows TRUE and FALSE. If these are missing the direction of flow is not known.
Table 2.5: Best practice in symbol detail
PRACTICE TASK 2.1
A
How would the flowchart in Demo Task 2.1 need to change to show the calculation of journey time based on a user input of preferred speed? Can you identify any other ambiguities in this flowchart?
DEMO TASK 2.2
S
Use a flowchart to represent a system that will output the results of an entrance examination for a university. The system requires the input of the maximum possible score in the examination and the score achieved by the candidate. Candidates who achieve 80% or more of the maximum score will be invited for an interview to decide if they will be offered a place at the university. Candidates who score less than 80% will be rejected.
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