Decipher Macro

[Mojojojo]

Hi there, I am currently stuck with some calculation project. And I have gotten an excel sheet which can helps but I never decode a Macro before. Is there anyone that can help me decode it and let me know what is the formula for the calculation?

Sub Button2_Click()
Dim speedstr As String
Dim DesSpeed As Single


DesSpeed = Sheet2.Cells(47, 5)


speedstr = InputBox("Please enter the vessel speeds in m/s separated by commas")


If speedstr = "" Then MsgBox "Please enter at least one value": Exit Sub


Dim arr


arr = Split(speedstr, ",")


Dim i As Integer


Sheet12.range("B4:C34").ClearContents




Dim count As Integer


count = 0


If UBound(arr) > 20 Then MsgBox "Maximum 20 values allowed": Exit Sub


For i = 0 To UBound(arr)


    'MsgBox "Speed No. " & i + 1 & " = " & arr(i)
    Dim currspeed As Single
    If arr(i) = "" Then Exit Sub
    
    If i > 0 Then
    If Val(arr(i)) < Val(arr(i - 1)) Then
    
    MsgBox "Please input the values in ascending order"
    
    Sheets("Speeds").Activate
    
    Exit Sub
    End If
    
    
    End If
    
    
    currspeed = arr(i)
    If Val(arr(i)) = 0 Then MsgBox "Please input a non-zero value for speed": Exit Sub
    
    Dim range As Excel.range
    Dim resistance As Double
    'range.Cells(2, i).Value = arr(i)
    




    If i > 0 Then
    If DesSpeed < Val(arr(i)) And DesSpeed > Val(arr(i - 1)) Then
    
            Sheets("Inputs - Vessel").Cells(47, 5).Value = DesSpeed
            Sheets("Graph").Cells(4 + count, 2).Value = DesSpeed
            resistance = Sheets("Final Forces").Cells(24, 4).Value
            Sheets("Graph").Cells(4 + count, 3).Value = Format(resistance, "#0.00")
            Sheet12.range(Sheet12.Cells(4 + count, 2), Sheet12.Cells(4 + count, 4)).Interior.Color = vbBlue
            count = count + 1
    End If
    End If
    
    Sheets("Inputs - Vessel").Cells(47, 5).Value = arr(i)
    
    resistance = Sheets("Final Forces").Cells(24, 4).Value
    
    Sheets("Graph").Cells(4 + count, 2).Value = arr(i)
    Sheets("Graph").Cells(4 + count, 3).Value = Format(resistance, "#0.00")


    Sheets("Graph").Activate
    
    count = count + 1
    
Next i




'''''''''Displaying the resistance at design speed
Sheets("Inputs - Vessel").Cells(47, 5).Value = DesSpeed


End Sub

[Paul_Hossler]

There's a number of sheets referenced in the macro that I have no idea

It's easier to trace a macro if it's indented and structured a little differently

See if you can trace this since you have a better idea of what it's supposed to do

Option Explicit


Sub Button2_Click()


    Dim speedstr As String
    Dim DesSpeed As Single
    Dim arr As Variant
    Dim i As Integer
    Dim count As Integer
    Dim currspeed As Single
    Dim range As range
    Dim resistance As Double


    DesSpeed = Sheet2.Cells(47, 5)
    
    speedstr = InputBox("Please enter the vessel speeds in m/s separated by commas")


    If speedstr = "" Then
        MsgBox "Please enter at least one value"
        Exit Sub
    End If


    arr = Split(speedstr, ",")
    Sheet12.range("B4:C34").ClearContents
    
    count = 0


    If UBound(arr) > 20 Then
        MsgBox "Maximum 20 values allowed"
        Exit Sub
    End If


    For i = 0 To UBound(arr)
    
        'MsgBox "Speed No. " & i + 1 & " = " & arr(i)
        If arr(i) = "" Then Exit Sub
    
        If i > 0 Then
            If Val(arr(i)) < Val(arr(i - 1)) Then
                MsgBox "Please input the values in ascending order"
                Sheets("Speeds").Activate
                Exit Sub
            End If
        End If
    
        currspeed = arr(i)
        
        If Val(arr(i)) = 0 Then
            MsgBox "Please input a non-zero value for speed"
            Exit Sub
        End If
        
        'range.Cells(2, i).Value = arr(i)
        
        If i > 0 Then
            
            If DesSpeed < Val(arr(i)) And DesSpeed > Val(arr(i - 1)) Then
                Sheets("Inputs - Vessel").Cells(47, 5).Value = DesSpeed
                Sheets("Graph").Cells(4 + count, 2).Value = DesSpeed
                resistance = Sheets("Final Forces").Cells(24, 4).Value
                Sheets("Graph").Cells(4 + count, 3).Value = Format(resistance, "#0.00")
                Sheet12.range(Sheet12.Cells(4 + count, 2), Sheet12.Cells(4 + count, 4)).Interior.Color = vbBlue
                count = count + 1
            End If
        End If
    
        Sheets("Inputs - Vessel").Cells(47, 5).Value = arr(i)
        
        resistance = Sheets("Final Forces").Cells(24, 4).Value
        
        Sheets("Graph").Cells(4 + count, 2).Value = arr(i)
        Sheets("Graph").Cells(4 + count, 3).Value = Format(resistance, "#0.00")
        Sheets("Graph").Activate
        
        count = count + 1
    Next i




    '''''''''Displaying the resistance at design speed
    Sheets("Inputs - Vessel").Cells(47, 5).Value = DesSpeed
End Sub