Using fractions in value list generated calculations

[Jarvis]

For my cabinetshop we often need to calculate the thickness of tile backslashes.

We build everything in metric but we communicate with our customers in imperial dimensions.

 

The various options for tile thickness are selected from a drop down value list.

 

For these values to be viable in a calculation they must be entered as a decimal.

If the inputed value starts out as a fraction the end result is gibberish.

 

The problem we have is our customers cannot sometimes relate to decimal equivalencies.

They don't readily understand that .375 is the same as 3/8 inch.

 

The attached file shows the results if we start with fractions or if we start with decimals.

Is there a way to use fractions as the value list input without filemaker considering them to be text values?

fractions.fmp12.zip

[Wim Decorte]

FileMaker will treat "3/8" as a text string as by using it in a calculation you are forcing FM to implicitly treat it as a number.  Which results in the number 38.  You can test this for yourself by checking this in the data viewer:

getasnumber( fractions::backsplash thickness from valuelist A )

 

You can however force FM to evaluate that text string as fraction by doing this:

Evaluate ( fractions::backsplash thickness from valuelist A)

which will result in 0.375

like you expect it to be

[Matthew F]

Change the definition of Metric Equivalence A to:  25.4 * Evaluate(backsplash thickness from valuelist A)

 

 

oops. Wim beat me to it. 

Edited December 13, 2014 by Matthew F

[Jarvis]

Thanks guys!  That was just what I needed.