我正在使用vb.net（Visual Studio 2013）并且必须在快速循环（0.000001 s）中执行一些数学运算：我得到n. def（非数字）作为结果。我想找出错误发生的位置，以便能够解决它;我尝试使用Try...Catch但没有成功。我还能尝试什么？谢谢你的帮助
' ---------------------------------------------------------------------------------------------------
' Lateral Segment Area Case 4
' ---------------------------------------------------------------------------------------------------
''' <summary>
''' LateralSegmentArea4: lateral segment area type 4
''' </summary>
''' <param name="y">crcle radius</param>
''' <param name="xm">radius of screw circle</param>
''' <param name="na">number of screws</param>
''' <param name="Fa">area calculated</param>
''' <param name="Test">Test: true|false</param>
''' <param name="destination">logging path</param>
''' <returns>status</returns>
''' <remarks></remarks>
Public Shared Function LateralSegmentArea4(y As Double,
xm As Double,
na As Double,
ByRef Fa As Double,
Test As Boolean,
destination As String) As Boolean
Dim ret As Boolean = True
Dim status As Boolean = True
Dim logstr As String = String.Empty
Dim psi As Double = 0
Dim ym As Double = 0
Dim found As Boolean = False
Dim alpha1 As Double = 0
Dim alpha2 As Double = 0
Dim phi As Double = 0
Dim x1 As Double = 0
Dim y1 As Double = 0
Dim x2 As Double = 0
Dim y2 As Double = 0
Dim Aseg As Double = 0
Dim result As Double = 0
Try
' psi
psi = 360 / na
' crosspoints x1, x2
ret = General.CrosspointsCircleStraightline(xm, ym, y, psi / 2, x2, x1, found, destination)
If found = True Then
y1 = Math.Tan(psi / 2 * Math.PI / 180) * x1
y2 = Math.Tan(psi / 2 * Math.PI / 180) * x2
' phi
alpha1 = Math.Asin(y1 / y)
If x2 >= xm Then
alpha2 = Math.Asin(y2 / y)
Else
alpha2 = Math.PI - Math.Asin(y2 / y)
End If
phi = Math.PI - alpha1 - alpha2
' segment area
Aseg = Math.Pow(y, 2) / 2 * (phi - Math.Sin(phi))
' lateral area
result = 2 * Aseg
Fa = result
If Test Then
Logging.WriteLogFile("", False, destination)
Logging.WriteLogFile("LateralSegmentArea4", False, destination)
Logging.WriteLogFile("x1: " & x1, False, destination)
Logging.WriteLogFile("y1: " & y1, False, destination)
Logging.WriteLogFile("x2: " & x2, False, destination)
Logging.WriteLogFile("alpha1: " & alpha1, False, destination)
Logging.WriteLogFile("alpha2: " & alpha2, False, destination)
Logging.WriteLogFile("phi: " & phi, False, destination)
Logging.WriteLogFile("Aseg: " & Aseg, False, destination)
End If
End If
Catch ex As Exception
logstr = "Error while getting lateral segment area 4 (" & ex.ToString & ")"
Logging.WriteLogFile(logstr, True, destination)
status = False
End Try
If status = True Then status = ret
Return status
End Function
' ---------------------------------------------------------------------------------------------------
' Crosspoints Circle Straight line
' ---------------------------------------------------------------------------------------------------
''' <summary>
''' CrosspointsCircleStraightline: determines crosspoint of circle and straight line
''' </summary>
''' <param name="xm">x-position of srew circle</param>
''' <param name="ym">y-position of srew circle</param>
''' <param name="r">circle radius</param>
''' <param name="phi">angle of straight line</param>
''' <param name="x1">x1-crosspoint</param>
''' <param name="x2">x2-crosspoint</param>
''' <param name="found">crosspoint found: true | false</param>
''' <param name="destination">logging path</param>
''' <returns>status</returns>
''' <remarks></remarks>
Public Shared Function CrosspointsCircleStraightline(xm As Double,
ym As Double,
r As Double,
phi As Double,
ByRef x1 As Double,
ByRef x2 As Double,
ByRef found As Boolean,
destination As String) As Boolean
Dim ret As Boolean = True
Dim status As Boolean = True
Dim logstr As String = String.Empty
Dim a As Double = 0
Dim part0 As Double = 0
Dim part1 As Double = 0
Dim part2 As Double = 0
Dim part3 As Double = 0
Dim part4 As Double = 0
Dim angle As Double = 0
Try
found = False
angle = phi * Math.PI / 180
a = Math.Tan(angle)
' part0 = 2*xm + 2*a*ym
part0 = 2 * xm + 2 * a * ym
' part1 = (2*xm + 2*a*ym)^2
part1 = Math.Pow((2 * xm + 2 * a * ym), 2)
' part2 = 4*(1+a^2)*(xm^2+ym^2-r^2)
part2 = 4 * (1 + Math.Pow(a, 2)) * (Math.Pow(xm, 2) + Math.Pow(ym, 2) - Math.Pow(r, 2))
' part3 = 2*(1+a^2)
part3 = 2 * (1 + Math.Pow(a, 2))
'part4 = (2*xm + 2*a*ym)^2 - 4*(1+a^2)*(xm^2+ym^2-r^2)
part4 = part1 - part2
If part4 < 0 Then
Threading.Thread.Sleep(100)
' repeat
part4 = part1 - part2
End If
' crosspoint found?
If part4 > 0 Then
found = True
x1 = (part0 + Math.Sqrt(part4)) / part3
x2 = (part0 - Math.Sqrt(part4)) / part3
Else
found = False
End If
Catch ex As Exception
logstr = "Error while finding cross points (" & ex.ToString & ")"
Logging.WriteLogFile(logstr, True, destination)
status = False
End Try
If status = True Then status = ret
Return status
End Function