CS 230 Spring 2007                          Assignment 11 – Arrays                                                   100 points

Assigned: 04/18/2007

Due: 04/27/2007 at the start of class (last day of class)

Pre-Lab (Do Before Lab):  Bring materials – a way to save a copy for you and a copy to turn in. Plan out tasks, objects, and events needed for program. Write pseudocode for the main buttons and for functions / independent sub procedures.

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Main Assignment:

· You have been recently hired by a professor to write a program to help figure out curves for tests. The scores from the test should be read in from a file (scores.txt) and displayed in a rich text box. These scores should be put into an array of scores as they are read in, since we will need to go back and revisit those scores.  Provide buttons and text boxes for trying out a potential method for determining the curve: Target Middle Mean = X (see below). Calculate a curve using a target specified by the user (see below). Once the curve has been determined, add it to all student scores, and display the updated scores in a second rich text box. Also, display information relevant to the method – the max, min, and middle mean, and the curve, plus the number of A’s, B’s, C’s, D’s, and F’s (in this simplified program no +’s or –‘s) in read only text boxes. 

· Provide the curve calculation capability, a clear capability, a clear all capability and an exit capability.

o The difference between Clear and Clear All is that the Clear All clears the results rich text box. Both versions clear the target, max, min, middle mean, and number of A’s, B’s, C’s etc

· A sample interface is provided on page 2. Don’t let that constrain your creativity. Use it to help understand what I see as the inputs and outputs.

Hand in:

• Floppy disk  or CD-R with an entire folder containing all files related to the project (or e-mail with zipped attachment containing all files related to the project).
• Please set the name of the project to something other than the default name (WindowsApplication1, …). It is helpful if you use a name that identifies you as well as the assignment (e.g. yourlastname assignment 10).
• Use Windows to copy the whole folder, instead of trying to “Save As”.
• Print out of your code.  

Task Details:

• Test scores can include decimals, so all variables related to scores (including array) should be doubles.
• A middle mean is defined (for the purpose of this assignment) as the mean of all values NOT INCLUDING the highest and lowest.
• In calculating the curve, enough points will be added to raise the middle mean to the target – BUT, make sure you NEVER subtract points!
• E.g. Middle Mean = 75; Target = 80 – curve is 5
• E.g. Middle Mean = 85;  Target = 82 – curve is 0
• Validation:

· Ensure that the target is are numeric, and the entered value is between 30 and 100. Don’t try to calculate anything if bad data has been entered (display a message).  

• You must use the filename specified above, so I can easily test a bunch of different programs in a row. Sample files are provided on the assignments page of my www site. In the spirit of thorough testing of programs, you should try other versions of files as well.
• We have covered procedures and functions – I recommend that you continue to use them (e.g. extracting a line of text from the text in a file, finding the largest value, etc).
• You cannot add points to the students’ scores until all students have been processed; that is one reason why we NEED arrays for this assignment.
• For simplicity in your first array assignment, we will not have any student names at all; the scores file will only contain scores, no names.
• For simplicity, we will assume that all test scores come from an accurate source, so will be in the correct range (0-100) (if there had been a problem, we would have to just ignore that score since we cannot re-prompt anybody fro a correction)
• The array should be large enough to handle a large class (100 students)

• MAKE SURE YOUR PROGRAM WORKS! (i.e. gets the correct answers).  It doesn’t have to just run, it needs to always run correctly!  It should correctly handle anything the user does. Branching is important in this program, so make sure to test on more than one case. Think up some different examples to test the program on. 

Miscellaneous

• You must turn on Option Explicit and Option Strict.
• Put YOUR NAME, e-mail address, date, and purpose of the program in comments at the beginning of the program. The purpose should be what the program is supposed to do, not the learning goals. Comments are indicated with a single quote (everything after the single quote is only for humans)
• You MUST include comments that explain your program in order to get full credit.
• Define numbers (especially those that appear more than once and/or could change sometime in the future) as named constants.
• Remember to use meaningful variable names
• Remember to indent to show the structure of the program (VB usually does this correctly).
• Name all textboxes, rich text boxes, comboboxes, and buttons meaningfully, and use conventions for starting their names.
• Make textboxes that user should never enter a value in (results / outputs) “Read Only”.
• Put your name on the form as a Label or as part of the form title.
• Try to use good user interface design. Make clear what user needs to do and what the answers mean. Make error messages as clear and helpful as possible!