fractional-arithmetic.js

A javascript library for doing fractional arithmetic.

Install

First do an `npm install fractional-arithmetic`.

Then, load the library into your code: `var Fraction = require('fractional-arithmetic').Fraction;`. You're good to go.

Example usage

``````var f = new Fraction( 7, 24 );
var g = Fraction( 11, 30 );
console.log( 'f=', f, 'g=', g );
console.log( 'f + g = ', f.plus(g) );
console.log( 'f - g = ', f.minus(g) );
console.log( 'f x g = ', f.times(g) );
console.log( 'f / g = ', f.dividedBy(g) );
console.log( 'latex f:', f.toLatex() );
console.log( 'number f:', f.toNumber() );

var pi= Fraction( 3.1415926 );
console.log( 'from decimal pi:', pi, pi.simplify() );
``````

API

C'tors

`Fraction(n,d)` creates the fraction "`n` over `d`" (`n` and `d` must be integers)

`Fraction(f)` if f is fraction, creates a new fraction equal to fraction f

`Fraction(d)` if f is decimal number, creates a new fraction equal to decimal number d

Arithmetic methods (can be chained)

`.add(f)`, `.plus(f)` both add fraction `f` to this fraction

`.add(n,d)`, `.plus(n,d)` both add "`n` over `d`" to this fraction (`n` and `d` must be integers)

`.minus(f)` subtracts fraction `f` from this fraction

`.minus(n,d)` subtracts "`n` over `d`" from this fraction (`n` and `d` must be integers)

`.times(f)`, `.multiply(f)` both multiply this fraction with fraction `f`

`.times(n,d)`, `.multiply(n,d)` both multiply this fraction with fraction "`n` over `d`" (`n` and `d` must be integers)

`.dividedBy(f)`, `.div(f)` both divide this fraction with fraction `f`

`.dividedBy(n,d)`, `.div(n,d)` both divide this fraction with fraction "`n` over `d`" (`n` and `d` must be integers)

`.inverse()` returns the inverse of this fraction (flips numerator & denominator)

Conversion methods

`.toString()`, `toS()`, `inspect()` return a human-readable string of this fraction

`.toLatex()` returns the fraction as a LaTeX command string

`.toMathML()` returns the fraction as a MathML string

`.toNumber()` returns the fraction as a decimal number (divides numerator by denominator)

Helpers

If you need to use these you can import them separately, like so:

``````var gcd = require('fractional-arithmetic').gcd;
``````

`gcd(a,b)` computes the Greatest Common Divisor of `a` and `b`

`lcm(a,b)` computes the Least Common Multiple of `a` and `b`

`isInteger(n)` true iff `n` is an integer

Exceptions

If an invalid fraction is specified, a `NotAFractionError` is thrown. For example, `Fraction('foobar')` will throw an error.

Grunt targets

These targets are available

Run jshint and nodeunit tests

``````grunt test
``````

Build the minified version

``````grunt build
``````

Run tests and build the minified version

``````grunt
``````

Feedback

Send me an email at alex.georgiou@gmail.com.