HOWTO: Convert a Fraction to a Decimal Number

• Microsoft Visual Basic for Applications version 5.0

SUMMARY

This article provides a routine to convert a string that contains a fraction in the form "a," "a/b," or "a b/c" into a double precision floating-point number.

MORE INFORMATION

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1. Create a new Visual Basic for Applications project and add the following code to a module:

   Sample Code

   
         Function Frac2Num(ByVal X As String) As Double
         Dim P As Integer, N As Double, Num As Double, Den As Double
            X = Trim$(X)
            P = InStr(X, "/")
            If P = 0 Then
               N = Val(X)
            Else
               Den = Val(Mid$(X, P + 1))
               If Den = 0 Then Error 11    ' Divide by zero
               X = Trim$(Left$(X, P - 1))
               P = InStr(X, " ")
               If P = 0 Then
                  Num = Val(X)
               Else
                  Num = Val(Mid$(X, P + 1))
                  N = Val(Left$(X, P - 1))
               End If
            End If
            If Den <> 0 Then
               N = N + Num / Den
            End If
            Frac2Num = N
         End Function 




2. In the Debug/Immediate window, test:

   ? Frac2Num("5 3/4"), Frac2Num("2/8")

   Result: 5.75 0.25

REFERENCES

For more information about getting help with Visual Basic for Applications, please see the following article in the Microsoft Knowledge Base:

Q163435 VBA: Programming Resources for Visual Basic for Applications

Additional query words: KbVBA kbVBp kbVBp500 kbDSupport kbDSD

Keywords :
Version : WINDOWS:5.0
Platform : WINDOWS
Issue type : kbhowto