ISBN : 978-81-963532-2-3 (E-Book) A decision tree gives a graphic view of the processing logic involved in decision making and the corresponding actions taken. The edges of a decision tree represent conditions and the leaf nodes represent the actions to be performed depending on the outcome of testing the condition. Example: - Consider Library Membership Automation Software (LMS) where it should support the following three options: • New member • Renewal • Cancel membership New member optionDecision: When the 'new member' option is selected, the software asks details about the member like the member's name, address, phone number etc. Action: If proper information is entered then a membership record for the member is created and a bill is printed for the annual membership charge plus the security deposit payable. Renewal optionDecision: If the 'renewal' option is chosen, the LMS asks for the member's name and his membership number to check whether he is a valid member or not. Action: If the membership is valid then membership expiry date is updated and the annual membership bill is printed, otherwise an error message is displayed. Cancel membership optionDecision: If the 'cancel membership' option is selected, then the software asks for member's name and his membership number. Action: The membership is cancelled, a cheque for the balance amount due to the member is printed and finally the membership record is deleted from the database. The following tree (fig. 6.1) shows the graphical representation of the above example. 26 Software Engineering Keerthana P, Manasa KN, Ganga D Bengal
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