How to store fraction value in text field and then convert it to decimal

[Guest]

I have a form where I need to store text field value as a fraction (like 2 1/8) and then convert to decimal. I tried to use custom calculation through javascript but some how it is not taking fraction value and converting it to decimal.Please help.

[Bernd Alheit]

What JavaScript code do you use?

[Guest]

Hello Bernd,I have used below code-

So field's formatting I am setting as none and then I enter value (say 2 1/4) as a fraction in it.I am splitting this value based on space and then getting all value as you can see, But when I enter value in field I don't get any thing converted in decimal.

var wholeNum = string(this.getField("fieldRow1").value).split(' ')[0]var fractionValue = string(this.getField("fieldRow1").value).split(' ')[1]

var fracNumerator = string(fractionValue ).split('/')[0]var fracDeno = string(fractionValue ).split('/')[1]var decimalVal = (wholeNum * fracDeno  + fracNumerator )/fracDeno if (!isFinite(decimalVal ) || isNaN(decimalVal )) {    event.value = "";} else {event.value = decimalVal ;}

Please let me know if you have any solution for this.

Thanks,Manisha

[Test Screen Name]

Some ideas for debugging your program. Use app.alert to check the values of your four variables after splitting. Check the console for errors.

[Bernd Alheit]

There are missing ; characters at the end of the statements.

[try67]

There's no built-in "string" method in JS. Instead, just use the valueAsString property of the fields you're accessing, or the .toString() method, or even cast your variable to a string like this: ""+myVariable ...

[try67]

I fixed your code and made some adjustments to handle an empty string or a number without a fraction correctly. It's not perfect but it's better than what you had and it should work...

var v = this.getField("fieldRow1").valueAsString;
var parts = v.split(" ");
if (parts.length<=1) event.value = v;
else {
    var wholeNum = Number(v.split(' ')[0]);
    var fractionValue = v.split(' ')[1];
    var fracNumerator = Number(fractionValue.split('/')[0]);
    var fracDeno = Number(fractionValue.split('/')[1]);
    var decimalVal = ((wholeNum * fracDeno) + fracNumerator) / fracDeno;
    if (!isFinite(decimalVal) || isNaN(decimalVal)) {event.value = "";} else {event.value = decimalVal ;}
}

[gkaiseril]

First let us look at what your input value could look like.

A whole number like 64 or "1)".

A fraction string like  "1/4".

A whole number plus a fraction string like "10 3/4" or "10-3/4".

With so many possible input variations I would look at using the Regular Expression object to identify which variation of the various inputs I have to process and then do the math. I would also use the "switch" statement so I only run the one conversion process that is needed and skip the other 2 options. I would also include a way to deal with a bad input value.

A possible function:

function ConvertFrac2Dec(cString)
{
// Convert a string of numberic values consisting of a whole number and fraciton string to a decimal number;
// invalid input will result in a return of a null value;

// convert numeric string with a fraction to a decimal number;
var nDecimal = null;
switch(true) {
  case /^(\d*)$/.test(cString) :
   nDecimal = RegExp.$1;
  break;

  case /^(\d*)\/(\d*)$/.test(cString):
   nDecimal = RegExp.$1 / RegExp.$2
  break;

  case /^(\d*)[ -](\d*)\/(\d*)$/.test(cString):
   nDecimal = Number(RegExp.$1) + Number((RegExp.$2 / RegExp.$3));
  break;

  default:
   // all other strings;
   nDecimal = null
  break;
}

return nDecimal;
} // end ConvertFrac2Dec function;

The custom calculation for the result field could be:

var nResult = ConvertFrac2Dec(this.getField("FractionString").value);

if(nResult == null)

{

app.alert("Invlid input for conversion from fractional string to decimal value", 1, 0);

event.vaue = "";

} else {

event.value = nResult;

}

You will have to adjust the input field name as needed.

[gkaiseril]

See  Fraction to Decimal for a working example of the script. It also include validation of the input and a sample calculation using fractional values.