How To Display a Number as a Fraction

MORE INFORMATION

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Function        Description
--------        -----------

Frac2Num        Returns a normalized fraction with the denominator in the
                range of 2..8.

Frac2NumA       Returns a non-normalized fraction with the denominator you
                specify.

Frac2NumB       Returns a normalized fraction based on a denominator you
                specify.
				

A normalized fraction contains the smallest possible denominator. The GCF() function (Greatest Common Factor) is used in the normalization process.

Example

Sample Code

1. Create a new project and add the following code to a Module:

         Function Num2Frac (ByVal X As Double) As String
         Dim Fixed As Double, Temp As String
           X = Abs(X)
           Fixed = Int(X)
           If Fixed > 0 Then
             Temp = CStr(Fixed)
           End If
           Select Case X - Fixed
             Case .1 To .145
               Temp = Temp + " 1/8"
             Case .145 To .182
               Temp = Temp + " 1/6"
             Case .182 To .225
               Temp = Temp + " 1/5"
             Case .225 To .29
               Temp = Temp + " 1/4"
             Case .29 To .35
               Temp = Temp + " 1/3"
             Case .35 To .3875
               Temp = Temp + " 3/8"
             Case .3875 To .45
               Temp = Temp + " 2/5"
             Case .45 To .55
               Temp = Temp + " 1/2"
             Case .55 To .6175
               Temp = Temp + " 3/5"
             Case .6175 To .64
               Temp = Temp + " 5/8"
             Case .64 To .7
               Temp = Temp + " 2/3"
             Case .7 To .775
               Temp = Temp + " 3/4"
             Case .775 To .8375
               Temp = Temp + " 4/5"
             Case .8735 To .91
               Temp = Temp + " 7/8"
             Case Is > .91
               Temp = CStr(Int(X) + 1)
           End Select
           Num2Frac = Temp
         End Function
   
         Function Num2FracA (ByVal X As Double, _
                             ByVal Denominator As Long) As String
         Dim Temp As String, Fixed As Double, Numerator As Long
           X = Abs(X)
           Fixed = Int(X)
           Numerator = Int((X - Fixed) * Denominator + .5) ' Rounding
           If Numerator = Denominator Then
             Fixed = Fixed + 1
             Numerator = 0
           End If
           If Fixed > 0 Then Temp = CStr(Fixed)
           If Numerator > 0 Then
             Temp = Trim$(Temp & " " & Numerator & "/" & Denominator)
           End If
           Num2FracA = Temp
         End Function
   
         Function Num2FracB (ByVal X As Double, _
                             ByVal Denominator As Long) As String
         Dim Temp As String, Fixed As Double, Numerator As Long
         Dim Factor As Long
           X = Abs(X)
           Fixed = Int(X)
           Numerator = Int((X - Fixed) * Denominator + .5)  ' Rounding
           If Numerator = Denominator Then
             Fixed = Fixed + 1
             Numerator = 0
           End If
           If Fixed > 0 Then
             Temp = CStr(Fixed)
           End If
           If Numerator > 0 Then
             Factor = GCF(Numerator, Denominator)  ' Factor for normalization.
             Temp = Trim$(Temp & " " & Numerator / Factor & "/" & _
                          Denominator / Factor)
           End If
           Num2FracB = Temp
         End Function
   
         Function GCF (ByVal X As Long, ByVal Y As Long) As Long
         '
         ' Returns the Greatest Common Factor.
         ' The largest number that will evenly divide into both X and Y.
         '
         Dim Temp As Long
           X = Abs(X)        ' Make both numbers positive.
           Y = Abs(Y)
           Temp = X Mod Y
           Do While Temp > 0
             X = Y
             Y = Temp
             Temp = X Mod Y
           Loop
           GCF = Y
         End Function
   						

2. Run the project and then press CTRL+BREAK to pause.
3. In the Debug/Immediate window, type the following:

   ?Num2Frac(3.54), Num2FracA(3.54,8), Num2FracB(3.54,8)

   Results:

   3 1/2
   3 4/8
   3 1/2