Human Readable Fractions

A small library to convert decimals to human readable fractions. Since the fractions are human readable, it means that they are not precise. The maximum denominator (right now) is 10. Also contains a function to convert fractions to decimals.

Info

• A JavaScript implementation of: http://www.ics.uci.edu/~eppstein/numth/frap.c
• Via: http://stackoverflow.com/questions/95727/how-to-convert-floats-to-human-readable-fractions
• Ruby gem implemenation: https://github.com/clord/fraction
• More info: https://en.wikipedia.org/wiki/Continued_fraction

API

• formatReadableFractionlink
• fractionToDecimal
• toReadableFraction

formatReadableFraction

Formats the readable fraction object as a string.

• @param {Object} fraction - The fraction object to convert to a string. It's recommended to use the result of toReadableFraction, but any array with the format of [numerator, denominator] is allowed.
• @param {Boolean} isImproper (optional) - If true, will return an improper fraction if the fraction object has a numerator greater than its denominator. @returns {String} The fraction object in string format.

Usage:

let fractionObject = {
  denominator: 3,
  error: -3.3333333332441484e-7,
  numerator: 1
};
let result = formatReadableFraction(fractionObject);
console.log(result);
// '1/3'

let fractionObject = {
  denominator: 5,
  error: -0.012500000000000178,
  numerator: 11
};
let result = formatReadableFraction(fractionObject);
console.log(result);
// '2 1/5'

let fractionObject = {
  denominator: 5,
  error: -0.012500000000000178,
  numerator: 11
};
let result = formatReadableFraction(fractionObject);
console.log(result);
// '11/5'

fractionToDecimal

Converts a fraction to a decimal. Unlike toReadableFraction, this is precise.

• @param {String} fraction - The fraction (as a string) to convert.
• @returns {Number} The converted fraction in decimal notation.

Usage:

let fraction = '1/4';
let result = fractionToDecimal(fraction);
console.log(result);
// 0.25

let fraction = '2 1/4';
let result = fractionToDecimal(fraction);
console.log(result);
// 2.25

toReadableFraction

Converts a decimal to a human readable fraction with a maximum denominator of 10. This means that the result is NOT precise.

• @param {Number} decimal - The decimal number to convert.
• @param {Boolean} shouldFormat (optional) - If true then the function will return a string instead of the fraction object.
• @returns {Object|String} A fraction object with keys: denominator, error, numerator; OR a formatted fraction string (This will always return a result with a proper fraction so if the decimal is greater than 1 then the resultwill never be improper (e.g. 12/5). To retrieve an improper fraction, call formatReadableFraction on the result of toReadableFraction.

Usage:

let decimal = 0.333333;
let result = toReadableFraction(decimal);
console.log(result);
// { denominator: 3, error: -3.3333333332441484e-7, numerator: 1 }

let decimal = 0.125;
let result = toReadableFraction(decimal, true);
console.log(result); // '1/8'

Contributing

Add the git post-commit hook

License

MIT