Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Dim CalculatingPi As Integer
Sub CalculateButton_Click()
If CalculatingPi = False Then
CalculatePi
Else
End
End If
End Sub
Sub CalculatePi()
Dim TimeSpent As Double
TimeSpent = Timer
OutputBox = "Initializing": DoEvents
CalculatingPi = True
CalculateButton.Caption = "Stop!"
Dim X As Integer
Dim CarryPosition As Integer
Dim NumberOfLoops As Integer
Dim LengthOfNumbers As Integer
LengthOfNumbers = TextBox_LengthOfNumbers + 3
NumberOfLoops = Int(2 / 3 * LengthOfNumbers)
ReDim ArcTangent5(1 To LengthOfNumbers) As String * 1
ReDim ArcTangent239(1 To LengthOfNumbers) As String * 1
ReDim MultipliedArcTangent5(1 To LengthOfNumbers + 1) As String * 1
ReDim MultipliedArcTangent239(1 To LengthOfNumbers + 1) As String * 1
OutputBox = "Calculating ArcTangent of 1/5": DoEvents
FindArcTangent 5, NumberOfLoops, LengthOfNumbers, ArcTangent5()
OutputBox = "Calculating the ArcTangent of 1/239": DoEvents
FindArcTangent 239, NumberOfLoops, LengthOfNumbers, ArcTangent239()
OutputBox = "Multiplying ArcTan of 1/5 by 16": DoEvents
MultiplyArray ArcTangent5(), 16, MultipliedArcTangent5()
OutputBox = "Multiplying ArcTan of 1/239 by 4": DoEvents
MultiplyArray ArcTangent239(), 4, MultipliedArcTangent239()
OutputBox = "Subtracting the Multiplied Arctangents": DoEvents
For X = LengthOfNumbers To 1 Step -1
If MultipliedArcTangent5(X) < MultipliedArcTangent239(X) Then
CarryPosition = X - 1
Do Until MultipliedArcTangent5(CarryPosition) <> "0"
MultipliedArcTangent5(CarryPosition) = "9"
CarryPosition = CarryPosition - 1
Loop
MultipliedArcTangent5(CarryPosition) = CStr(CInt(MultipliedArcTangent5(CarryPosition)) - 1)
MultipliedArcTangent5(X) = CStr((CInt(MultipliedArcTangent5(X)) + 10) - CInt(MultipliedArcTangent239(X)))
Else
MultipliedArcTangent5(X) = CStr(CInt(MultipliedArcTangent5(X)) - CInt(MultipliedArcTangent239(X)))
End If
DoEvents
Next X
Dim PiValue As String
OutputBox = ""
For X = 1 To LengthOfNumbers - 3
PiValue = PiValue & MultipliedArcTangent5(X)
If X Mod 5 = 0 Then
PiValue = PiValue & " "
End If
Next X
OutputBox = PiValue
MsgBox "Pi calculated to " & LengthOfNumbers - 3 & " decimal places." & Chr$(13) & "Completed " & NumberOfLoops & " iterations." & Chr$(13) & "Spent " & (Timer - TimeSpent) / 60 & " minutes calculating.", 64, "Calculations Complete"
CalculatingPi = False
End Sub
Sub FindArcTangent(ArcTanToFind As Integer, NumberOfLoops As Integer, LengthOfNumbers As Integer, ArcTangent() As String * 1)
Dim StartPos As Integer
Dim Sum As Long
Dim X As Integer
Dim Divisor As Long
Dim Remainder As Long
Dim CarryPosition As Long
Dim DividedInto As Integer
ReDim Answer(1 To LengthOfNumbers) As String * 1
ReDim Divided(1 To LengthOfNumbers) As String * 1
StartPos = 1
责任编辑：小草
