RosettaCodeData/Task/Arithmetic-geometric-mean/Visual-Basic-.NET/arithmetic-geometric-mean-1.vb

31 lines
1.1 KiB
VB.net

Imports System.Math
Imports System.Console
Module Module1
Function CalcAGM(ByVal a As Double, ByVal b As Double) As Double
Dim c As Double, d As Double = 0, ld As Double = 1
While ld <> d : c = a : a = (a + b) / 2 : b = Sqrt(c * b)
ld = d : d = a - b : End While : Return b
End Function
Function DecSqRoot(ByVal v As Decimal) As Decimal
Dim r As Decimal = CDec(Sqrt(CDbl(v))), t As Decimal = 0, d As Decimal = 0, ld As Decimal = 1
While ld <> d : t = v / r : r = (r + t) / 2
ld = d : d = t - r : End While : Return t
End Function
Function CalcAGM(ByVal a As Decimal, ByVal b As Decimal) As Decimal
Dim c As Decimal, d As Decimal = 0, ld As Decimal = 1
While ld <> d : c = a : a = (a + b) / 2 : b = DecSqRoot(c * b)
ld = d : d = a - b : End While : Return b
End Function
Sub Main(ByVal args As String())
WriteLine("Double result: {0}", CalcAGM(1.0, DecSqRoot(0.5)))
WriteLine("Decimal result: {0}", CalcAGM(1D, DecSqRoot(0.5D)))
If System.Diagnostics.Debugger.IsAttached Then ReadKey()
End Sub
End Module