Chapter 7 Flashcards
(23 cards)
Describe analysis
The first stage of the program development life cycle that involves investigating the problem. The problem is explored and the requirements of the program are identified.
Describe design
The second stage of the program development life cycle that involves the decomposition of the problem and algorithms created ready for implementation. This can include an overview of the program using a structure diagram and the designing of algorithms using flowcharts and pseudocode.
Decomposition
Taking a system and splitting it into smaller sub systems which can in turn be split into smaller sub systems.
Structure diagram
A hierarchical diagram that shows the decomposition of a system
Flowchart
A diagrammatic representation of an algorithm
Pseudocode
Code like statements used to design an algorithm but do not follow any specific language. Uses keywords and constructs like IF statements, while loops, etc..
Describe coding
The writing of a program using one or more programming languages. Includes iterative testing (testing carried out while the program is being developed)
Describe testing
Repeated use of a system to try all different possibilities to make sure the system is fully working, cannot be broken, meets all requirements and doesnt crash. (We use test data to test a program.)
Types of test data
Normal: Should be accepted Abnormal: Shouldnt be accepted Boundary: On the edge of being accepted and being rejected Extreme: On the edge of what is allowed
Search algorithm
A series of steps that searches for a specific value in a set of data
Sorting algorithm
A series of steps that will rearrange the data into an order
Linear search
A search algorithm that visits each item of data in turn to check if it is the data being looked for, continuing until it either finds the item or checks the last value
Bubble sort
Sorting algorithm that moves through the list repeatedly swapping values in pairs. Takes the first two values, compares them and swaps them if theyre in the wrong order. It then moves on with values 2 and 3 and does the same process. This continues until it has worked all the way through the list once. It then starts again with the first two values.
Totalling
Statements in a program that add together a set of data to produce a total. Initialise the variable to 0 and add the value to the current contents of the total.
Counting
Statements in a program that record how many of something there are. Initialise the variable to 0 tehn add 1 to the count variable each time.
Minimum
The smallest item in a set of data. Initialise the minimum value to a very large number and compare each value to the minimum. The value replaces the minimum if it is smaller than it
Maximum
The largest item in a set of data. Initialise the maximum value to a very small number and compare each value to the maximum. The value replaces the maximum if it larger than it
Average
The mean of a set of values, the total divided by the quantity
Validation
The checking of data to make sure it is reasonable and within set bounds. Eg; Range check, type check, format check, presence check, check digit, length check
Verification
Checking that data is entered accurately, that it is the same as the original
Visual check
Comparing the data entered with the original side by side
Double entry check
Two different people enter the same data which are then compared
Trace table
A structure to complete when walking through an algorithm manually where the values that change are written in each row
