Option Explicit

Private Function pRound(ByVal Value As Double, ByVal Power As Double) As Double
    Dim TempValue As Double
    Dim tSign As Double
    TempValue = Value
    tSign = TempValue
    TempValue = Abs(TempValue)
    TempValue = TempValue * 10 ^ (Power * -1)
    TempValue = Fix(TempValue + 0.5)
    TempValue = TempValue / 10 ^ (Power * -1)
    pRound = TempValue * Sgn(tSign)
End Function

Sub zadachka()
    Dim x As Double, x1 As Double, x2 As Double
    Let x = Sqr(2#)
    Let x1 = Val(CStr(x))
   
    x = pRound(x, -8)
    x1 = pRound(x1, -8)
    
    If x <> x1 Then MsgBox "Elementary, Watson!"
    Let x2 = Val(CStr(x - x1))
    If x <> x1 + x2 Then MsgBox "What about this?"
End Sub

Private Sub Form_Load()
  zadachka
End Sub

// Initialize two doubles with apparently identical values
double double1 = .33333;
double double2 = (double) 1/3;
// Compare them for equality
Console.WriteLine(double1.Equals(double2));    // displays false

' Compares two numbers to see if they meet the comparison condition
' within the specified tolerance.
' Valid comparison operators are, "=" "<", ">", "<=", and ">=".
Public Function NumbersCompare(Value1 As Double, Value2 As Double, _
           operator As String, _
           Optional Tolerance As Double = 0.000000000001) As Boolean
    Dim difference As Double
    difference = Abs(Value1 - Value2)
   
    Dim comparison As String
    comparison = ""
    Dim equals As Boolean
    equals = False
    If Len(operator) = 2 Then
        ' Determine if the operator is greater or less than.
        If Mid(operator, 1, 1) = ">" Then
            comparison = ">"
        ElseIf Mid(operator, 1, 1) = "<" Then
            comparison = "<"
        Else
            MsgBox "Bad comparison operator: " & operator
            NumbersCompare = False
            Exit Function
        End If
       
        ' Determine if equals to is specified.
        If Mid(operator, 2, 1) = "=" Then
            equals = True
        Else
            MsgBox "Bad comparison operator: " & operator
            NumbersCompare = False
            Exit Function
        End If
    ElseIf Len(operator) = 1 Then
        ' Determine if the operator is greater than,
        ' less than, or equals to.
        If operator = ">" Then
            comparison = ">"
        ElseIf operator = "<" Then
            comparison = "<"
        ElseIf operator = "=" Then
            equals = True
        Else
            MsgBox "Bad comparison operator: " & operator
            NumbersCompare = False
            Exit Function
        End If
    Else
        MsgBox "Bad comparison operator: " & comparison
        NumbersCompare = False
        Exit Function
    End If
   
    ' Do the actual comparisons.
    If operator = ">" Then
        ' Check if the value is greater than, using the tolerance.
        If Value1 + Tolerance > Value2 Then
            NumbersCompare = True
            Exit Function
        Else
            NumbersCompare = False
        End If
    ElseIf operator = "<" Then
        ' Check if the value is less than, using the tolerance.
        If Value1 - Tolerance < Value2 Then
            NumbersCompare = True
            Exit Function
        Else
            NumbersCompare = False
        End If
    End If

    ' Check if the numbers are equal, within the tolerance.
    If equals Then
        If difference <= Tolerance Then
            NumbersCompare = True
            Exit Function
        Else
            NumbersCompare = False
        End If
    End If
End Function

Public Sub CompareNumbers3()
    Dim val1 As Double
    val1 = 0.1 + 0.1 + 0.1

    Dim val2 As Double
    val2 = 0.3

    Debug.Print "val1 = " & CStr(val1) & ", val2 = " & CStr(val2)

    If NumbersCompare(val1, val2, "<=") Then
        Debug.Print "Values compare"
    Else
        Debug.Print "Values do not compare"
    End If
End Sub