week 14

Dim n As Integer

 Dim spec As String 

Const period As Integer = 4

 Const maxerror As 

Double = 0.0000001 

Dim payment(period) As Double '廣域變數 4 維度的陣列 

Private Sub CommandButton1_Click()

 Dim a, b, c, f, gap As Double 

 Dim loopNumber As Integer n = n + 1 '第幾次計算+1 a = 0 '報酬率0 b = 1 '報酬率1 gap = 10 loopNumber = 10 payment(0) = TextBox1.Value payment(1) = TextBox2.Value payment(2) = TextBox3.Value payment(3) = TextBox4.Value f = npv(a) If f = 0 Then Label9.Caption = 0 ElseIf f < 0 Then Label9.Caption = "內部報酬率小於 0." Else Do While gap > mexerror And Abs(f) > maxerror And loopNumber < 100 loopNumber = loopNumber + 1 c = (a + b) / 2 f = npv(c) If Abs(f) > maxerror And gap > maxerror Then If f > 0 Then a = c Else b = c gap = b - a End If Else Label9.Caption = c End If Loop End If Label10.Caption = f Label11.Caption = loopNumber ' 'spec = "躉繳$" & payment(0) & ", 第1期$" & payment(1) & ",第2期$" & payment(2) & ",第3期$" & payment(3) Cells(n, 1).Value = "第" & n & "次執行" Cells(n, 2).Value = "內部報酬率:" & c Cells(n, 3).Value = "淨現值:" & f Cells(n, 4).Value = "迴圈次數:" & loopNumber End Sub Private Sub CommandButton2_Click() End End Sub Function npv(rate) '計算特定折現率rate的淨現值 Dim y As Double Dim j As Integer y = -payment(0) For j = 1 To period y = y + payment(j) / (1 + rate) ^ j Next npv = y End Function Private Sub CommandButton3_Click() Selection.WholeStory Selection.Delete End Sub Private Sub CommandButton4_Click() Selection.WholeStory Selection.Delete End Sub Private Sub CommandButton5_Click() Selection.Font.Bold = True Selection.Font.Size = 16 Selection.Font.Color = RGB(0, 0, 255) End Sub