Question

用VB计算圆周率,步骤写清楚精确到1000位

Answer 1

Private Sub Command1_Click()

getpi 1000

End Sub

Sub getpi(Optional ByVal nums As Long = 10000)

nums = nums / 5

Dim max As Long, laptime As Single, result() As String

Dim i, j As Long, d As Long, t, g, r, k As Long, f()

laptime = Timer

max = 10 * nums

ReDim f(1 To max)

ReDim result(nums)

result(0) = vbCrLf

For i = 1 To max

f(i) = 30000

Next

For j = max To 1 Step -10

t = 0

For i = j To 1 Step -1

If j = max Then

t = t + f(i) * 1000000

Else

t = t + f(i) * 100000

End If

r = 8 * i * (2 * i + 1)

f(i) = t - Int(t / r) * r

d = 2 * i - 1

t = Int(t / r) * d * d

Next

k = k + 1

result(k) = Format(Int(g + t / 100000) Mod 100000, "00000")

If k Mod 20 = 0 Then result(k) = result(k) & vbCrLf

If k Mod 200 = 0 Then result(k) = result(k) & "---[" & k * 5 & "]---" & vbCrLf

g = t Mod 100000

Next

Text1.Text = Join(result, " ")

Me.Caption = "计算完毕!总计用时" & Timer - laptime & "秒!"

End Su