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Decimal To Fraction

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4.67/5 (6 votes)

Jun 10, 2010

CPOL
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16669

Converts a given decimal number to fraction

Function dec2frac(ByVal dblDecimal As Double) As String
  Dim intNumerator, intDenominator, intNegative As Integer
        Dim dblFraction, dblAccuracy As Double
        Dim txtDecimal As String

        dblAccuracy = 0.1                                       ' Set the initial Accuracy level.
        txtDecimal = dblDecimal.ToString                        ' Get a  string representation of the input number.

        For i As Integer = 0 To (txtDecimal.Length - 1)                                 ' Check each character to see if it's a decimal point...
            If txtDecimal.Substring(i, 1) = "." Then                    ' if it is then we get the number of digits behind the decimal
                dblAccuracy = 1 / 10 ^ (txtDecimal.Length - i)    '   assign the new accuracy level, and
                Exit For                                            '   exit the for loop.
            End If
        Next
        intNumerator = 0                                ' Set the initial numerator value to 0.
        intDenominator = 1                              ' Set the initial denominator value to 1.
        intNegative = 1                                 ' Set the negative value flag to positive.
        If dblDecimal < 0 Then
            intNegative = -1 ' If the desired decimal value is negative,
        End If

        dblFraction = 0                                 ' Set the fraction value to be 0/1.

        Do While Math.Abs(dblFraction - dblDecimal) > dblAccuracy   ' As long as we're still outside the
            '   desired accuracy, then...
            If Math.Abs(dblFraction) > Math.Abs(dblDecimal) Then      ' If our fraction is too big,
                intDenominator += 1         '   increase the denominator
            Else                                            ' Otherwise
                intNumerator += intNegative   '   increase the numerator.
            End If

            dblFraction = intNumerator / intDenominator     ' Set the new value of the fraction.

        Loop

        Return intNumerator.ToString & "/" & intDenominator.ToString ' Display the numerator and denominator
    End Function
    Function num(ByVal dblDecimal As Double) As String
        Dim intNumerator, intDenominator, intNegative As Integer
        Dim dblFraction, dblAccuracy As Double
        Dim txtDecimal As String

        dblAccuracy = 0.1                                       ' Set the initial Accuracy level.
        txtDecimal = dblDecimal.ToString                        ' Get a  string representation of the input number.

        For i As Integer = 0 To (txtDecimal.Length - 1)                                 ' Check each character to see if it's a decimal point...
            If txtDecimal.Substring(i, 1) = "." Then                    ' if it is then we get the number of digits behind the decimal
                dblAccuracy = 1 / 10 ^ (txtDecimal.Length - i)    '   assign the new accuracy level, and
                Exit For                                            '   exit the for loop.
            End If
        Next
        intNumerator = 0                                ' Set the initial numerator value to 0.
        intDenominator = 1                              ' Set the initial denominator value to 1.
        intNegative = 1                                 ' Set the negative value flag to positive.
        If dblDecimal < 0 Then
            intNegative = -1 ' If the desired decimal value is negative,
        End If

        dblFraction = 0                                 ' Set the fraction value to be 0/1.

        Do While Math.Abs(dblFraction - dblDecimal) > dblAccuracy   ' As long as we're still outside the
            '   desired accuracy, then...
            If Math.Abs(dblFraction) > Math.Abs(dblDecimal) Then      ' If our fraction is too big,
                intDenominator += 1         '   increase the denominator
            Else                                            ' Otherwise
                intNumerator += intNegative   '   increase the numerator.
            End If

            dblFraction = intNumerator / intDenominator     ' Set the new value of the fraction.

        Loop

        Return intNumerator.ToString
    End Function
    Function den(ByVal dblDecimal As Double) As String
        Dim intNumerator, intDenominator, intNegative As Integer
        Dim dblFraction, dblAccuracy As Double
        Dim txtDecimal As String

        dblAccuracy = 0.1                                       ' Set the initial Accuracy level.
        txtDecimal = dblDecimal.ToString                        ' Get a  string representation of the input number.

        For i As Integer = 0 To (txtDecimal.Length - 1)                                 ' Check each character to see if it's a decimal point...
            If txtDecimal.Substring(i, 1) = "." Then                    ' if it is then we get the number of digits behind the decimal
                dblAccuracy = 1 / 10 ^ (txtDecimal.Length - i)    '   assign the new accuracy level, and
                Exit For                                            '   exit the for loop.
            End If
        Next
        intNumerator = 0                                ' Set the initial numerator value to 0.
        intDenominator = 1                              ' Set the initial denominator value to 1.
        intNegative = 1                                 ' Set the negative value flag to positive.
        If dblDecimal < 0 Then
            intNegative = -1 ' If the desired decimal value is negative,
        End If

        dblFraction = 0                                 ' Set the fraction value to be 0/1.

        Do While Math.Abs(dblFraction - dblDecimal) > dblAccuracy   ' As long as we're still outside the
            '   desired accuracy, then...
            If Math.Abs(dblFraction) > Math.Abs(dblDecimal) Then      ' If our fraction is too big,
                intDenominator += 1         '   increase the denominator
            Else                                            ' Otherwise
                intNumerator += intNegative   '   increase the numerator.
            End If

            dblFraction = intNumerator / intDenominator     ' Set the new value of the fraction.

        Loop

        Return intDenominator.ToString
    End Function