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麻烦有能力的朋友帮我编个渐开线函数的反函数,最好用vB编写!
用什么二分法呀,牛顿法呀,都随便你们,最近忙毕业设计没空研究!
题目: 已知 渐开线函数 inv(a)=tan(a) -a (其中a为弧度)
那么现在已知inv(a)的值,麻烦高手帮我编出解出a值的程序!
不用把程序给我,写上代码在答案里就行了!十分感谢! 
采纳率：55%
10级
2013.06.25
AInv (0.02842)
24.5822867713287
Public Function Inv(a As Double) As Double
Inv = Tan(a) - a
End Function
Public Function AInv(num As Double) As Double
Dim lowangle As Double
Dim highangle As Double
Dim midangle As Double
lowangle = 0
highangle = Atn(1) * 2
Do While highangle - lowangle > 10 ^ -12
midangle = (lowangle + highangle) / 2
If Inv(midangle) > num Then
highangle = midangle
Else
lowangle = midangle
End If
Loop
AInv = (lowangle + highangle) / 2 / Atn(1) * 45
End Function
加个牛顿法的
Public Function AInv2(num As Double) As Double
Dim x1 As Double
Dim x2 As Double
x2 = Atn(1)
Do
x1 = x2
x2 = x1 - (Tan(x1) - x1 - num) / (1 / Cos(x1) ^ 2 - 1)
Loop While Abs(x2 - x1) > 10 ^ -12
AInv2 = x2 / Atn(1) * 45
End Function |
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