![decimal.js-light](https://raw.githubusercontent.com/MikeMcl/decimal.js-light/gh-pages/decimaljslight.png) The light version of [decimal.js](https://github.com/MikeMcl/decimal.js/), an arbitrary-precision Decimal type for JavaScript. [![Build Status](https://travis-ci.org/MikeMcl/decimal.js-light.svg)](https://travis-ci.org/MikeMcl/decimal.js-light)
This library is the newest of the family of libraries: [bignumber.js](https://github.com/MikeMcl/bignumber.js/), [big.js](https://github.com/MikeMcl/big.js/), [decimal.js](https://github.com/MikeMcl/decimal.js/) and *decimal.js-light*.
The API is more or less a subset of the API of *decimal.js*. ![API](https://raw.githubusercontent.com/MikeMcl/decimal.js-light/gh-pages/API.png) __Differences between this library and *decimal.js*__ Size of *decimal.js* minified: 32.1 KB.
Size of *decimal.js-light* minified: 12.7 KB. This library does not include `NaN`, `Infinity` or `-0` as legitimate values, or work with values in other bases. Here, the `Decimal.round` property is just the default rounding mode for `toDecimalPlaces`, `toExponential`, `toFixed`, `toPrecision` and `toSignificantDigits`. It does not apply to arithmetic operations, which are simply truncated at the required precision. If rounding is required just apply it explicitly, for example ```js x = new Decimal(2); y = new Decimal(3); // decimal.js x.dividedBy(y).toString(); // '0.66666666666666666667' // decimal.js-light x.dividedBy(y).toString(); // '0.66666666666666666666' x.dividedBy(y).toDecimalPlaces(19).toString(); // '0.6666666666666666667' ``` The `naturalExponential`, `naturalLogarithm`, `logarithm`, and `toPower` methods in this library have by default a limited precision of around 100 digits. This limit can be increased at runtime using the `LN10` (the natural logarithm of ten) configuration object property. For example, if a maximum precision of 400 digits is required for these operations use ```js // 415 digits Decimal.set({ LN10: '2.302585092994045684017991454684364207601101488628772976033327900967572609677352480235997205089598298341967784042286248633409525465082806756666287369098781689482907208325554680843799894826233198528393505308965377732628846163366222287698219886746543667474404243274365155048934314939391479619404400222105101714174800368808401264708068556774321622835522011480466371565912137345074785694768346361679210180644507064800027' }); ``` Also, in this library the `e` property of a Decimal is the base 10000000 exponent, not the base 10 exponent as in *decimal.js*.
Use the `exponent` method to get the base 10 exponent. ## Quickstart Browser: ```html
``` Node package manager: ```shell $ npm install --save decimal.js-light ``` ```js // Node.js var Decimal = require('decimal.js-light'); // Adjust the global configuration if required (these are the defaults) Decimal.set({ precision: 20, rounding: Decimal.ROUND_HALF_UP, toExpNeg: -7, toExpPos: 21 }); phi = new Decimal('1.61803398874989484820458683436563811772030917980576'); phi.toFixed(10); // '1.6180339887' phi.times(2).minus(1).toPower(2).plus('1e-19').equals(5); // true ``` See the [documentation](http://mikemcl.github.io/decimal.js-light) for further information. [TypeScript](https://github.com/Microsoft/TypeScript) type declaration file contributed by [TANAKA Koichi](https://github.com/MugeSo).