SDD

SDD

1. Development Methodologies

   • Iterative (Waterfall)
     • Waterfall
       • A -> D -> I -> T -> D -> E -> M
     • Iterative
       • A -> D -> I -> T <- D -> I -> T -> D -> E -> M
     • Iteration between stages
       • Return to design after I or T
     • Iteration within stages
       • Repeating interviews in the A stage
   • Agile
     • Rapid Application Development
       • Can result in chaotic development process
     • Sprints
       • Planned delivery schedule for an aspect of system
       • Time-consuming as they require near-daily comms
         • Large scale projects are often unrealistic

2. Analysis

   • Purpose
     • Expressed as a description of what the software will be used for
   • Scope
     • List of what must be delivered over the course of the project
       • Design
       • Completed Program
       • Test plan and results
       • Evaluation report
   • Boundaries
     • Limits set on the program
   • Functional Requirements
     • Specify inputs, processes and outputs

3. Design

   • Design techniques
     • Pseudocode
       • English-like
     • Flow chart
       • Demonstrates flow of data
     • Structure diagram
       • Breaks program down into steps
   • Wireframes
     • Designs how program will look
   • Data Flow
     • Shows which variables are present in each sub-section

4. Implementation

   • Subprograms
     • Top-level Algrotihm
       • Designs how data moves between subprograms
     • Procedures and functions
       • Procedures
         • Produce and effect, not a value
       • Functions
         • Produce a value
       • Passing
         • By Value
           • Parameter required but value will not change
         • By Reference
           • Parameter required but value will change
     • Variables
       • Parameters
         • Formal parameters
           • Used within subprogram
         • Actual Parameters
           • Listed when the subprogram is called from within the main program
       • Local and Global
         • Local
           • Scope: Within a subprogram
         • Global
           • Scope: Main Program
   • Pre-defined Functions
     • Modulus
       • Calculates remainder of a division sum
     • Random
       • Generates a random number
     • Length
       • Calculates length of string
     • Round
       • Rounds a float to decimal places

5. Testing

   • Types of errors
     • Syntax
       • Program will not run
       • Error in writing the code
     • Execution
       • Doing something illegal in programming language
       • Program will crash
     • Logic
       • Incorrect output
       • Incorrect mathematics
   • Types of testing
     • Breakpoints
       • Stops a program at a certain point to check variables are correct
     • Dry run
       • Following variables on pen and paper throughout the program
     • Test Table
       • Track variables at different points in the program
     • Watchpoints

6. Documentation

7. Evaluation

8. Maintenance