SDD Flashcards
Waterfall Method
This is the term used to describe the design process of a piece of software
It is made up of these 5 stages:
- Analysis
- Design
- Implementation
- Testing
- Evaluation
Iteration
Iteration means ‘to do over again’
The software development process is described as iterative because each stage may have to be revisited as a result of new information coming to light
Inputs
What data is being input into your program
E.g.
Length = inputbox(“Give the length”)
Breadth = inputbox(“Give the breadth”)
Processes
What the program calculates for you
E.g.
Area = Length * Breadth
Outputs
What the program displays when it is complete
E.g.
Msgbox(Area)
Input, Process and Output Example
‘Declare variables
Dim Length as integer
Dim Breadth as integer
Dim Area as integer
‘Get Inputs
Length = inputbox(“Enter Length”)
Breadth = inputbox(“Enter Breadth”)
‘Calculate Area
Area = Length * Breadth
‘Display Area
Msgbox(Area)
Structure Diagram
Structure diagrams break down a problem into smaller sections
These smaller sections cam then be worked on one at a time
This can be good for big projects where a large problem can be split into smaller tasks for separate groups, or individuals, to work on
Flowchart
Flow charts show what is going on in a program and how data flows around it
Flow charts represent everyday processes, show decisions taken and the result of these decisions
Pseudocode
When designing a program, it is useful to pay out how the program might work, before writing it in a programming language
Pseudocode is a design notation that is closely related to teh logic of how a program will work
Pseudocode can look alot like code but it DOES NOT NEED to be implemented as strictly
Wireframe
Just as we learned in the Web Design and Development unit, a wireframe is used to design the layout of a programs User Interface
This provides a skeletal outline of the components of the interface
Variables
Variables are used to store information to be referenced and manipulated in a computer program
They also provide a way of labelling data with a descriptive name, so our programs can be understood more clearly by the reader and ourselves
It is helpful to think of varianles as containeres that hold information
Their sole purpose is to label and store data in memory
This data can then be used throughout your program
Data Types
In National 5, when we create a variable we will store them as a following data type:
Characters - Storing a single letter
String - Storing anything that contains letters
Integer - Storing whole numbers
Real - Storing numbers that have a decimal point
Boolean - Storing data that can only have 2 values
Array - Storing a list of 1 data type
Declating Variables
Dim Grade as Char Dim Forname as String Dim Age as Integer Dim Height as Single Dim Valid as Boolean
Assinging Values
Grade = "A" Forename = "Big Tasty" Age = 40 Height = 1.82 Valid = False
Declaring Arrays
Dim Name(9) as String
This sets aside a space in memory to store 10 names (0 - 9)
Assinging Array Values
Name(0) = "Chris P.Bacon" Name(1) = "Jed I Knight" Name(2) = "Joelle Rollo-Koster" Name(3) = "Deja Viau" Name(4) = "Tahra Dactyl" Name(5) = "Brock Lee" Name(6) = "Jass Singsasong" Name(7) = "Sam Sung" Name(8) = "Vol Demort" Name(9) = "Christian Guy"
Assihninh Array Vaules (Loop)
For i = 0 to 9
Name(i) = Inputbox(“Enter a Name”)
ListBox1.Items.Add(Name(i))
Next
It would provide the same answer if you asked for the same output as the first example