Functions RESOLVED

I seem to think that this program might be a little off the mark when it comes to doing a function properly. Can anyone look at the code I have produced and see. It is supposed to take in 3 grade scores, display them from smallest to largest and tell you what the grade average is, then it is supposed to tell you what grade is required to get a (60=D,70=C,80=B,90=A) and if the grade is above 100 N/A will be displayed. Mine works but I was afraid I was missing the mark with the function since I really don't have any code under the function part.

VB Code:

Option Explicit
Private Sub cmdCompute_Click()
Dim n1 As Single, n2 As Single, n3 As Single
Dim avg As Single
Dim GrA As Single, GrB As Single, GrC As Single, GrD As Single
Dim Res As String
Res = "N/A"
n1 = txtGr1.Text
n2 = txtGr2.Text
n3 = txtGr3.Text
Rank n1, n2, n3
lblGr1.Caption = n1
lblGr2.Caption = n2
lblGr3.Caption = n3
avg = (n1 + n2 + n3) / 3
lblRes.Caption = Round(avg)
GrA = (90 - (avg * 0.6)) / 0.4
GrB = (80 - (avg * 0.6)) / 0.4
GrC = (70 - (avg * 0.6)) / 0.4
GrD = (60 - (avg * 0.6)) / 0.4
lblGrA.Caption = FormatNumber(GrA, 1)
lblGrB.Caption = FormatNumber(GrB, 1)
lblGrC.Caption = FormatNumber(GrC, 1)
lblGrD.Caption = FormatNumber(GrD, 1)
If GrA > 100 Then
    lblGrA.Caption = Res
End If
    
End Sub
 
Private Sub Rank(ByRef x As Single, ByRef y As Single, ByRef z As Single)
'Order scores from low (Gr1) to high (Gr3)
    If x > y Then Swap x, y
    If y > z Then Swap y, z
    If x > y Then Swap x, y
End Sub
 
Private Sub Swap(ByRef n1 As Single, ByRef n2 As Single)
    Dim temp As Single
    temp = n1
    n1 = n2
    n2 = temp
End Sub
 
Private Function Score(ByVal currAvg As Single, ByVal finalAvg As Single) As String
  Score = (currAvg * 0.6) + (finalAvg * 0.4)
    
        
        
           
End Function

How does the avg relate to the grade they need to get an A, B, C, or D?. Sorry I'm from Aus, we may do things differently here.

I'm trying to work out what this code is supposed to do

VB Code:

GrA = (90 - (avg * 0.6)) / 0.4
GrB = (80 - (avg * 0.6)) / 0.4
GrC = (70 - (avg * 0.6)) / 0.4
GrD = (60 - (avg * 0.6)) / 0.4

FW

Sorry I guess I left the most important out. To figure out the grade you need on the final the current average is 60% of the grade and the final is 40% of the grade. So that was the nearest formula I could figure out with all the options figured in to. If I could have just used one grade it would of made life a whole lot easier. I thought I would need to figure out a way for the program to know the options of either getting an A - D.

So the grade they got in this test acounts for 60% of the term grade. You wanrt to know what they need to get in the final to achieve an A, B, C, D?

Is that right?

Yes that is exactly right. My mind wandered for 2 days trying to figure out how to put that down in a program. The last test accounts for 40%

Here is a function that returns the score needed in the finals as a percentage.
It assumes you are entering the first score (perhaps the mark for the project) as a percentage.

What the function does is turn that percentage into a score out of 60. It then subtracts this score from the grade levels, and this gives you a mark you must get out of 40. It then turns this mark out of 40 back into a percent.

To use it, call the function for each score once for each target grade. That will mean a total of 12 calls to it.

eg textStudent1ScoreNeededForAnA.Text = GetFinalsScoreNeeded (TheMarkTheyGot, "A")

VB Code:

Private Function GetFinalsScoreNeeded(ProjectScore As Single, Grade As String) As String
    Dim sngFinalsScoreNeeded As Single
    Dim sngProjectScore As Single
    
    'convert the project into a mark out of 60
    sngProjectScore = ProjectScore * 0.6
    
    'get the percent needed to get the grade
    Select Case Grade
        Case "A"
            sngFinalsScoreNeeded = 90 - sngProjectScore
        Case "B"
            sngFinalsScoreNeeded = 80 - sngProjectScore
        Case "C"
            sngFinalsScoreNeeded = 70 - sngProjectScore
        Case "D"
            sngFinalsScoreNeeded = 60 - sngProjectScore
    End Select
    'Check if it's more than 100% needed
    If (sngFinalsScoreNeeded / 40) * 100 > 100 Then
        GetFinalsScoreNeeded = "N/A"
    Else
        'returns the percent needed as as string
        GetFinalsScoreNeeded = CStr((sngFinalsScoreNeeded / 40) * 100)
    End If
End Function

Good luck

FW

freewilly I took what you gave me and revamped it to do what I needed. I now have a problem where the scores show up in my label boxes but they are the same score throughout. Where it should be showing me individual scores for each grade. The function is supposed to return the string N/A only when greater than 100. If it is greater than 100 for an A it will give me N/A on all 4 label boxes. It should be given me the final score needed in the other three boxes don't you think. Here is the revamped code.

VB Code:

Option Explicit
 
Private Sub cmdCompute_Click()
Dim n1 As Single, n2 As Single, n3 As Single
Dim avg As Single
Dim Res As Single
n1 = txtGr1.Text
n2 = txtGr2.Text
n3 = txtGr3.Text
Rank n1, n2, n3
lblGr1.Caption = n1
lblGr2.Caption = n2
lblGr3.Caption = n3
avg = (n1 + n2 + n3) / 3
lblRes.Caption = Round(avg)
lblGrA.Caption = Score(avg, Res)
lblGrB.Caption = Score(avg, Res)
lblGrC.Caption = Score(avg, Res)
lblGrD.Caption = Score(avg, Res)
 
 
    
End Sub
 
Private Sub Rank(ByRef x As Single, ByRef y As Single, ByRef z As Single)
'Order scores from high (Gr1) to low (Gr3)
    If y > x Then Swap x, y
    If z > y Then Swap y, z
    If y > x Then Swap x, y
End Sub
 
Private Sub Swap(ByRef n1 As Single, ByRef n2 As Single)
    Dim temp As Single
    temp = n1
    n1 = n2
    n2 = temp
End Sub
 
Private Function Score(ByVal currAvg As Single, ByVal finalAvg As Single) As String
Dim A As Single, B As Single, C As Single, D As Single
Dim sngcurrAvg As Single
Dim sngFinalScoreNeeded As Single
sngcurrAvg = currAvg * 0.6
 
Select Case finalAvg
Case A
    sngFinalScoreNeeded = (90 - sngcurrAvg) / 0.4
Case B
    sngFinalScoreNeeded = (80 - sngcurrAvg) / 0.4
Case C
    sngFinalScoreNeeded = (70 - sngcurrAvg) / 0.4
Case D
    sngFinalScoreNeeded = (60 - sngcurrAvg) / 0.4
End Select
 
If sngFinalScoreNeeded > 100 Then
    Score = "N/A"
Else
    Score = sngFinalScoreNeeded
End If
         
End Function

ldyslp4

Why are you pasing res which is a single?
In your code the Select Case choses a case based on finalAvg
I don't see how this can work.
Try replacing

VB Code:

lblGrA.Caption = Score(avg, Res)
lblGrB.Caption = Score(avg, Res)
lblGrC.Caption = Score(avg, Res)
lblGrD.Caption = Score(avg, Res)

with

VB Code:

lblGrA.Caption = Score(avg, "A")
lblGrB.Caption = Score(avg, "B")
lblGrC.Caption = Score(avg, "C")
lblGrD.Caption = Score(avg, "D")

and change the second parameter of the Score function back to a String.

FW

The reason I was doing that is because I have to have four different scores in my label boxes. If I use the string method won't I just be getting grades (A, B, C, D) in my boxes?
Never mind I just tried what you said and it gives me exactly what you said. Thanks alot. By the way I was writing that code that way because that is what we was given to use

VB Code:

Private Function Score (ByVal currAvg As Single, ByVal finalAvg As Single) As String

Then it went on to say to use FormatNumber to pass a value and return a string.
But at this point and time I really could care less as long as mine will do what it is required to do.

No, the function sets the return of Score with the code

VB Code:

If sngFinalScoreNeeded > 100 Then
    Score = "N/A"
Else
    Score = sngFinalScoreNeeded
End If

What this will do is convert sngFinalScoreNeeded to a string and return it to cmdCompute_Click.
The function name Score acts like a variable of the return type, in this case a string. It takes its value from the code above.

When you call

VB Code:

lblGrA.Caption = Score(avg, Res)

it places the Value that was assigned to Score, in the If statement above, into lblGrA.Caption.

How well do you understand select cases?
The case statement looks at a value and makes a decision base on you logic.

Select Case strGradeRequired
Case "A"
'code to generate the grade needed to get an A
etc

I thought I was understanding the select case pretty well but when she gave us that statement to use for function it threw me for a loop. I was trying every way possible to make it work. In fact I started with the select case in the beginning but couldn't possibly understand how to make a formula that would work for each individual one. It seemed very redundant. I am just a beginner in this subject. When I try to do what is asked and it only works the wrong way then I get frustrated. I knew my function was supposed to contain the calculations so that it could get passed a value and then send it on to cmd click.
Thanks alot for your assistance. You have been great. :D

I didn't quite have the problem clear in my mind, but i do now.
Here's how I think your code should look.

VB Code:

Private Function Score(ByVal currAvg As Single, Grade As String) As String
 
    Dim sngFinalsScoreNeeded As Single
    Dim sngScoreOurOf60 As Single
    
    'convert the project into a mark out of 60
    sngScoreOurOf60 = currAvg * 0.6
    
    'get the percent needed to get the grade
    Select Case Grade
        Case "A"
            sngFinalsScoreNeeded = 90 - sngScoreOurOf60
        Case "B"
            sngFinalsScoreNeeded = 80 - sngScoreOurOf60
        Case "C"
            sngFinalsScoreNeeded = 70 - sngScoreOurOf60
        Case "D"
            sngFinalsScoreNeeded = 60 - sngScoreOurOf60
    End Select
    'Check if it's more than 100% needed
    If (sngFinalsScoreNeeded / 40) * 100 > 100 Then
        Score = "N/A"
    Else
        'returns the percent needed as as string
        Score = CStr((sngFinalsScoreNeeded / 40) * 100)
    End If
End Function

The code to call it is

VB Code:

lblGrA.Caption = Score(avg, "A")
lblGrB.Caption = Score(avg, "B")
lblGrC.Caption = Score(avg, "C")
lblGrD.Caption = Score(avg, "E")

I have tested this and it works

You need to learn about debuging as well. If you click on the grey section to the left of the code a red dot will appear. When the code gets to the dot it will stop and display it to you. You can then step through the code by pressing F8. You can see the values of most variables by hovering over them with the mouse. You can do heaps more than this when debugging but this will get you started.