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Merge pull request #28 from pra85/patch-1

Add syntax highlighting
This commit is contained in:
Michael M 2016-02-23 19:07:28 +00:00
commit dc642c0429

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@ -36,23 +36,23 @@ Another major difference is that this library enables multiple Decimal construct
The library is the single JavaScript file *decimal.js* (or minified, *decimal.min.js*).
It can be loaded using a script tag in an HTML document for the browser
```html
<script src='path/to/decimal.js'></script>
```
or as a [Node.js](http://nodejs.org) module using `require`.
```javascript
var Decimal = require('decimal');
```
For Node, the library is available from the [npm](https://npmjs.org/) registry
```bash
$ npm install decimal.js
```
To load with AMD loader libraries such as [requireJS](http://requirejs.org/):
```javascript
require(['decimal'], function(Decimal) {
// Use Decimal here in local scope. No global Decimal.
});
```
## Use
*In all examples below, `var`, semicolons and `toString` calls are not shown.
@ -61,69 +61,69 @@ If a commented-out value is in quotes it means `toString` has been called on the
The library exports a single function object, `Decimal`, the constructor of Decimal instances.
It accepts a value of type number, string or Decimal.
```javascript
x = new Decimal(123.4567)
y = new Decimal('123456.7e-3')
z = new Decimal(x)
x.equals(y) && y.equals(z) && x.equals(z) // true
```
A value can also be in binary, hexadecimal or octal if the appropriate prefix is included.
```javascript
x = new Decimal('0xff.f') // '255.9375'
y = new Decimal('0b10101100') // '172'
z = x.plus(y) // '427.9375'
z.toBinary() // '0b110101011.1111'
z.toBinary(13) // '0b1.101010111111p+8'
```
A Decimal is immutable in the sense that it is not changed by its methods.
```javascript
0.3 - 0.1 // 0.19999999999999998
x = new Decimal(0.3)
x.minus(0.1) // '0.2'
x // '0.3'
```
The methods that return a Decimal can be chained.
```javascript
x.dividedBy(y).plus(z).times(9).floor()
x.times('1.23456780123456789e+9').plus(9876.5432321).dividedBy('4444562598.111772').ceil()
```
Many method names have a shorter alias.
```javascript
x.squareRoot().dividedBy(y).toPower(3).equals(x.sqrt().div(y).pow(3)) // true
x.cmp(y.mod(z).neg()) == 1 && x.comparedTo(y.modulo(z).negated()) == 1 // true
```
Like JavaScript's Number type, there are `toExponential`, `toFixed` and `toPrecision` methods,
```javascript
x = new Decimal(255.5)
x.toExponential(5) // '2.55500e+2'
x.toFixed(5) // '255.50000'
x.toPrecision(5) // '255.50'
```
and many of the methods of JavaScript's Math object are also replicated.
```javascript
Decimal.sqrt('6.98372465832e+9823') // '8.3568682281821340204e+4911'
Decimal.pow(2, 0.0979843) // '1.0702770511687781839'
```
There are `isNaN` and `isFinite` methods, as `NaN` and `Infinity` are valid `Decimal` values,
```javascript
x = new Decimal(NaN) // 'NaN'
y = new Decimal(Infinity) // 'Infinity'
x.isNaN() && !y.isNaN() && !x.isFinite() && !y.isFinite() // true
```
and a `toFraction` method with an optional *maximum denominator* argument
```javascript
z = new Decimal(355)
pi = z.dividedBy(113) // '3.1415929204'
pi.toFraction() // [ '7853982301', '2500000000' ]
pi.toFraction(1000) // [ '355', '113' ]
```
All calculations are rounded according to the number of significant digits and rounding mode
specified by the `precision` and `rounding` properties of the Decimal constructor.
As mentioned above, multiple Decimal constructors can be created, each with their own independent
configuration which applies to all Decimal numbers created from it.
```javascript
// Set the precision and rounding of the default Decimal constructor
Decimal.config({ precision: 5, rounding: 4 })
@ -135,14 +135,14 @@ As mentioned above, multiple Decimal constructors can be created, each with thei
x.div(3) // '1.6667'
y.div(3) // '1.666666666'
```
The value of a Decimal is stored in a floating point format in terms of its digits, exponent and sign.
```javascript
x = new Decimal(-12345.67);
x.d // [ 12345, 6700000 ] digits (base 10000)
x.e // 4 exponent (base 10)
x.s // -1 sign
```
For further information see the [API](http://mikemcl.github.io/decimal.js/) reference in the *doc* directory.
## Test
@ -152,28 +152,28 @@ The library can be tested using Node.js or a browser.
The *test* directory contains the file *test.js* which runs all the tests when executed by Node, and the file *test.html* which runs all the tests when opened in a browser.
To run all the tests, from a command-line at the root directory using npm
```bash
$ npm test
```
or at the *test* directory using Node
```bash
$ node test
```
Each separate test module can also be executed individually, for example, at the *test/modules* directory
```bash
$ node toFraction
```
## Build
For Node, if [uglify-js](https://github.com/mishoo/UglifyJS2) is installed
```bash
npm install uglify-js -g
```
then
```bash
npm run build
```
will create *decimal.min.js*, and a source map will also be added to the *doc* directory.
## Feedback