Question

利用圆周率的近似值计算公式pi/4=1-1/3+1/5-1/7+1/9… 要求最后一项的绝对值小于0.000001时停止计算!

Answer 1

'VB:

Private Sub Form_Click()

    Dim pi As Double, i As Double, n As Double

    pi = 0

    i = 0

    Do While 1 = 1

        i = i + 1

        n = (1 / ((i - 1) * 2 + 1)) * (-1) ^ (i - 1)

        pi = pi + n

        If Abs(n) < 0.000001 Then

            Exit Do

        End If

    Loop

    Print pi * 4

End Sub