maths question - extracting numbers

[ianpaisley]

Hi there,

I use the code below to generate 2 groups of numbers, A and B, into my picturebox. The groups, or sets, are determined randomly. A random question (one of 3 questions) is loaded below the sets.

For example, when command1 is clicked, the picturebox might say:

------

A = {1,3,4,6,9)
B = {2,4,7,9}

What is A intersect B?

------

What I want to happen next is when they click command2, it gives them the answer in my label, label1.

In this case the answer would be: A intersect B is {4,9}.

Does anybody know how I can do this. I know it's some sort of loop or something, but I'm not sure of the code.

The other questions are:

What is A union B? (a list of the contents of A and B, without repetition

What is A less B? (a list of numbers in A that are not in B)

I attach my code below, in the hope that someone might know.

Thanks for any help!

-----------------

' 2 command buttons, a label, a picturebox

Private Sub Command1_Click()

Dim numbertoprint As Integer
Dim numbertoprint2 As Integer
Dim intSeqNbr(1 To 8) As Integer
Dim intSeqNbr2(1 To 8) As Integer
Dim intX As Integer
Dim intX2 As Integer
Dim strPrintData As String
Dim strPrintData2 As String
Dim strCommaOrNot As String
Dim setsquestion As Integer

Picture1.Cls
Randomize
'there will be two sets, A and B
'decide the amount of numbers, from 4 to 8, to print for
'both sets in the Picturebox
numbertoprint = Int(Rnd * 5) + 4
numbertoprint2 = Int(Rnd * 5) + 4
'decide the space there will be between numbers
intSeqNbr(1) = Int(Rnd * 4) + 1
intSeqNbr2(1) = Int(Rnd * 4) + 1
'intX loops through the amount of numbers selected and
'adds an amount onto each one
For intX = 2 To 8
'add an amount, from 1 to 3, onto each number
intSeqNbr(intX) = intSeqNbr(intX - 1) + Int(Rnd * 3) + 1
Next
For intX2 = 2 To 8
intSeqNbr2(intX2) = intSeqNbr2(intX2 - 1) + Int(Rnd * 3) + 1
Next

strPrintData = "A = {"
strPrintData2 = "B = {"

'For every number chosen in the sequence....
For intX = 1 To numbertoprint
'....add a comma at the end of it, except the last number
strCommaOrNot = IIf(intX = 1, "", ",")

'this is the random sequence of numbers, commas and all
strPrintData = strPrintData & strCommaOrNot & intSeqNbr(intX)

Next

For intX2 = 1 To numbertoprint2

strCommaOrNot = IIf(intX2 = 1, "", ",")

strPrintData2 = strPrintData2 & strCommaOrNot & intSeqNbr2(intX2)
Next

'Now print the sets in the Picturebox
Picture1.Print strPrintData & "}" & vbCr & strPrintData2 & "}"

'There are 3 different questions that can be asked.
'choose 1 at random.
setsquestion = Int(Rnd * 3)
Select Case setsquestion

Case "0"
Picture1.Print vbCr & vbCr & vbCr & "What is A intersect B?"

Case "1"
Picture1.Print vbCr & vbCr & vbCr & "What is A union B?"

Case "2"
Picture1.Print vbCr & vbCr & vbCr & "What is A less B?"
End Select

End Sub

[ca9mbu]

What you need to do is set up a loop within a loop.

Try the following code to get a list of numbers that are in A and not B:

Dim i as integer, j as integer, k as integer, l as integer
Dim numbersA(1 to 5) as integer, numbersB(1 to 5) as integer
Dim Unison(1 to 10) as integer, Different(1 to 10) as integer

i=0
j=0
k=0
l=0

For i = 0 to UBound(numbersA)
  For j = 0 to Ubound(numbersB)
    If numbersA(i) <> numbersB(j) Then
      Different(k) = numbersA(i)
      k=k+1
      Exit For
    End If
  Next j
Next i

For your unison query try:

For i = 0 to UBound(numbersA)
  For j = 0 to UBound(numbersB)
    For k = 0 to UBound(Unison)
      If numbersA(i) = numbersB(j) Then
        If numbersA(i) <> Unison(k) Then
          Unison(k) = numbersA(i)
          Exit For
        End If
      End If
    Next k
  Next j
Next i

Hope this works, or at least helps you out.

Matt

[ianpaisley]

ca9mbu,

I had a look at your code but couldn't get it working. However, I found a way to do it. The problem is that it's very long winded and I know there's a quicker way to loop around it or something, but I don't know how. Could someone give me a hand?

Basically, IntSeqNbr is the amount of numbers that appear at random for set A - this can be from 4 to 8 numbers. IntSeqNbr is for set B.

What the code below does is print the numbers that set A has in common with B.

E.g:

'the question:

A = {3,5,8,9,11}
B = {6,8,9,12}

What is A intersect B?

' the answer:

8,9

Here's my code:

'As I said, it's very long and would appreciate if someone 'could help 'me shorten it. Thanks.

Private Sub Command2_Click()

If intSeqNbr(1) = intSeqNbr2(1) Then
Picture1.Print intSeqNbr(1) & ",";
End If
If intSeqNbr(1) = intSeqNbr2(2) Then
Picture1.Print intSeqNbr(1) & ",";
End If
If intSeqNbr(1) = intSeqNbr2(3) Then
Picture1.Print intSeqNbr(1) & ",";
End If
If intSeqNbr(1) = intSeqNbr2(4) Then
Picture1.Print intSeqNbr(1) & ",";
End If
If intSeqNbr(1) = intSeqNbr2(5) Then
Picture1.Print intSeqNbr(1) & ",";
End If
If intSeqNbr(1) = intSeqNbr2(6) Then
Picture1.Print intSeqNbr(1) & ",";
End If
If intSeqNbr(1) = intSeqNbr2(7) Then
Picture1.Print intSeqNbr(1) & ",";
End If
If intSeqNbr(1) = intSeqNbr2(8) Then
Picture1.Print intSeqNbr(1) & ",";
End If
If intSeqNbr(2) = intSeqNbr2(1) Then
Picture1.Print intSeqNbr(2) & ",";
End If
If intSeqNbr(2) = intSeqNbr2(2) Then
Picture1.Print intSeqNbr(2) & ",";
End If
If intSeqNbr(2) = intSeqNbr2(3) Then
Picture1.Print intSeqNbr(2) & ",";
End If
If intSeqNbr(2) = intSeqNbr2(4) Then
Picture1.Print intSeqNbr(2) & ",";
End If
If intSeqNbr(2) = intSeqNbr2(5) Then
Picture1.Print intSeqNbr(3) & ",";
End If
If intSeqNbr(2) = intSeqNbr2(6) Then
Picture1.Print intSeqNbr(3) & ",";
End If
If intSeqNbr(2) = intSeqNbr2(7) Then
Picture1.Print intSeqNbr(3) & ",";
End If
If intSeqNbr(2) = intSeqNbr2(8) Then
Picture1.Print intSeqNbr(3) & ",";
End If

'etc...etc....until we get to intseqnbr(8) = intseqnbr2(8)

End Sub

[Sam Finch]

Try this

Private Sub Intersect(SetA() As Variant, SetB As Variant)
Dim intStartDifference As Integer
Dim i As Integer
Dim j As Integer

intStartDifference = LBound(SetA) - LBound(SetB)

For i = LBound(SetA) To UBound(SetA)

    For j = i + intStartDifference To UBound(SetB)
    
        If SetA(i) = SetB(j) Then _
            Picture1.Print SetA(i) & "."
    
    Next j
    
Next i


End Sub

then you only need one line

Call Intersect(intSeqNbr, intSeqNbr2)