Formats a number value into a fraction with optional accuracy

fractionalize_value.js

/*
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| Formats a number value into a fraction with optional accuracy
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*/
function fractionalizeValue(value, fractions)
{
  // default to 16th
  fractions = fractions === undefined ? 16 : fractions;

  // extract whole number, remainder and our numerator
  var wholeNumber = Math.floor(value);
  var remainder = value - wholeNumber;
  var numerator = Math.round(remainder / (1 / fractions));
  var denominator = fractions; 
  var output = '';
  var unicodeEntities = {
    '1/4': '¼',
    '1/2': '½',
    '3/4': '¾',
    
    '1/3': '⅓',
    '1/3': '⅔',
    
    '1/5': '⅕',
    '2/5': '⅖',
    '3/5': '⅗',
    '4/5': '⅘',

    '1/6': '⅙',
    '5/6': '⅚',

    '1/8': '⅛',
    '3/8': '⅜',
    '5/8': '⅝',
    '7/8': '⅞'
  };

  // can we simplify our fraction, do it until we can't any more
  while(numerator % 2 === 0 && denominator % 2 === 0)
  {
    numerator = numerator / 2;
    denominator = denominator / 2;
  }

  if(numerator === 1 && denominator === 1)
  {
    wholeNumber += 1;
    numerator = 0;
  }
  
  // format our output
  if(wholeNumber > 0)
  {
    output = wholeNumber;
  }
  
  // add fraction
  if(numerator > 0)
  {
    if(wholeNumber > 0)
    {
      output += ' ';
    }

    if(unicodeEntities[numerator + '/' + denominator])
    {
      output += unicodeEntities[numerator + '/' + denominator];
    }
    else
    {
      output += numerator + '/' + denominator;
    }
  }

  return output;
}