W Mart, a new retail chain, has announced a discount on the total sale amount, in a single transaction, using the following scheme.
Table 1: Discount on Sale Amount
Total Sale Amount
Discount on this sale amount
Less than \$100
0%
From \$100 up to less than \$500
10% for each dollar over \$100
From \$500 up to less than \$1,000
\$40 PLUS 20% of the total sale amount over \$500
From \$1,000 up to less than \$2,000
\$140 PLUS 30% of the total sale amount over \$1,000
\$2,000 and above
\$440 PLUS 40% of the total sale amount over \$2,000
That is, if the total sale amount is \$100 then the discount will be \$0. However, if the total sale amount is \$101 then the discount will be \$0.10. If the total sale amount is \$500 then the discount will be \$40, but if the total sale amount is \$501 then the discount will be \$40.20.
W Mart keeps track of a customer through a unique customer ID. W Mart gives one reward point for every \$100 spent irrespective of the number of transactions. The points accumulate over the time for a customer for his/her purchases. Finally, for each 100 reward points it gives an additional discount of \$10 on a purchase over \$10 in a transaction.
Write a Python program that, for every transaction, takes input on the customer ID and the total sale amount in the transaction. It then reads a text file called discount.txt that stores information on the discount on sales amount as shown in Table 1 above. The text file stores the information in a plain text format as follows.
Less than \$100 –> 0%
From \$100 up to less than \$500 –> 10%
From \$500 up to less than \$1,000 –> \$40 PLUS 20%
From \$1,000 up to less than \$2,000 –> \$140 PLUS 30%
\$2,000 and above –> \$440 PLUS 40%
At the end of each transaction the following information is written (appended) out in a file called sales.txt. The same information is also displayed on screen.

Customer ID: 1
Total sale amount: 110
Discount amount: 1
Discounted sale amount: 109
Reward point: 1
Cumulative sale amount for the next reward point: 10

Final sale amount: 109
Use appropriate data structure in writing your code.
All exceptions need to be handled. Invalid inputs need to be handled and asked for a valid input again.
Use functions to make your program well designed, instead of just using a single main function. For example, you could use a function to take inputs from a user, a function to compute the discount, a function to compute the reward points, a function to display the output on the screen and so on. We expect you to use at least four (4) functions other than the main function.
In order to compute the reward points of a customer your program will need to read the sales.txt file. A customer is identified by her/his unique Customer ID, and may appear multiple times in the sales.txt file.
Write an algorithm in structured English (pseudocode) that describes the steps required to perform the task specified. Some examples of pseudocode can be found athttp://www.unf.edu/~broggio/cop2221/2221pseu.htm.
Avoid duplicate code.
Comment your code as necessary to explain it clearly.
Select 3 sets of test data that will demonstrate the correct “normal” operation of your program.
Run your program using the test data you have selected and save the output it produces in a text file.
Submit:
2. The table recording your chosen test data.
3. Source code for your Python implementation.
4. Output listings demonstrating the results of using the test data.
It is important that the output listings are not edited in any way.
Rationale
Reinforce topic material related to files and exceptions.
Reinforce topic material related to lists.
Marking criteria
Assessment Criteria
Performance Standards
FL
(Does not meet the PS requirements)
0 – 49 %
PS
(Meets the requirements below)
50 – 64 %
CR
(Meets PS requirements plus those below)

65 – 74 %
DI
(Meets CR requirements plus those below)

75 – 84 %
HD
(Meets DI requirements plus those below)
85 – 100 %
0 – .99
1 – 1.29
1.3 – 1.49
1.5 – 1.69
1.7 – 2.0 marks
Produce an algorithm in pseudocode (structured English).
(2 marks)
A significant number of errors in the produced algorithm.
Only a small number of errors in the produced algorithm.
It uses multiple functions.
It uses appropriate loops.
No errors in the produced algorithm.
File reading and writing is done as instructed in the assignment task.
All variable names in the produced algorithm are meaningful.
A good design of the functions has been used.
All statements in the produced algorithm are necessary.
0 – .49
.5 – .64
.65 – .74
.75 – .84
.85 – 1.0 mark
Select appropriate test data.
Present the test results.
(1 mark)
Selected test data are not clearly presented in a table or do not allow easy calculation of output.
Selected test data are clearly presented in a table and allow easy calculation of output.
Selected test data present normal operation of the code.
Sound reasons are provided for the selection of test data.
Test data explore every branch of the program.
Clear explanation provided of the expected output of the test results.
0 – 2.99
3 – 3.89
3.9 – 4.49
4.5 – 5.09
5.1 – 6 marks
Produce the necessary Python code.
(6 marks)
The produced Python code does not execute properly, and/or contains syntax errors and/or produces incorrect results.
The produced Python code executes properly without any syntax errors producing correct results.
It uses multiple functions.
It uses appropriate loops.
The produced Python code is fully documented with appropriate comments.
All variable names are meaningful.
File reading and writing is done as instructed in the assignment task.
The produced Python code implements the pseudocode correctly.
A good design of the functions has been used.
The produced Python code contains only necessary statements and variables.
0 – .49
.5 – .64
.65 – .74
.75 – .84
.85 – 1.0 mark
Present the actual output of the program.
(1 mark)
The presented test output does not match the actual results that can be obtained from the execution of the program.
The presented test output matches the actual results that can be obtained from the execution of the program.
The presented test output is correct.
The test output is correct for any test data in addition to those used in the submitted table to report the test result.
The presented test output is in the form specified in the assignment.
Presentation
You MUST prepare and present all source code, output from test runs, and other documentation as separate files within a single directory (folder) identified by your name. This directory will later be compressed into a single ZIP file – see the “Requirements” section below.
The Python source code you write should be saved with a name such as assA1.py by choosing File > Save As.. from the IDLE “edit” window.
The test run (or runs) produced when your Python program executes should be saved with a name such as assA1.txt by choosing File > Save As.. from the IDLE “run” window. (N.B. When testing your final program, start with a new (empty) run window, perform ALL necessary test runs one after the other, then when finished save the contents of the “run” window into ONE file showing ALL test runs in the order that you carried them out. This order should match the order of the test in your “test data table”).
The other documentation (such as your pseudocode, and your table of test data etc) should be saved in a Word document with a name such as assA1.doc.
Thus your directory for Assignment A1 will contain three files – and be identified with your name (and not the name of the subject or the assignment).

It is critically important that your test runs (saved as one file with a .txt extension) are unmodified outputs from your program, and that these results should be reproducible by the marker running your saved .py python program in IDLE. In this subject test runs, and python program listings are NOT to be cut and pasted in from the IDLE windows with modifications. For example you might be tempted to cut the output from test runs and to paste it into a Word document to create a “pretty” assignment with headers and footers the way you might be used to doing for other subjects. DO NOT DO THIS! The un-edited contents of the “edit” and “run” windows from IDLE is all we want to see in the .py program listing file and the .txt test run file.
Requirements
Once you have saved the three files (as described under “Presentation” above) into a single directory
identified by your name, you MUST compress that directory into a single ZIP file (and only a ZIP file
– not a RAR file or some other compressed file format), as outlined in the section on presentation.
Failure to adhere to these requirements will attract a 10% penalty.