Length.js

JavaScript Library for Length Units Conversion

Table of Contents

• Installation
• Usage
• Methods
• Contributing
• License

Installation

Length.js was designed to work both in the browser and in Node.js.

Browser

<script src="length.js"></script>

Length.js is available on unpkg CDN in compressed and uncompressed version.

Node.js

$ npm install length.js

var length = require('length.js');
// or using ES6 import
import length from 'length.js';

Usage

Length.js creates an object which contains value and unit. To get this object, simply call length() with two supported arguments. Then you can call available methods.

The Length prototype is exposed through length.fn (if you want to add your own functions).

length(value, unit)

Creates an object which contains value and unit.

Arguments

• value (Number): Number of units.

• unit (String): Unit type.

  Available unit types:

  • pm: picometre: (1 / 1 000 000 000 000) m,
  • nm: nanometre: (1 / 1 000 000 000) m,
  • um: micrometre: (1 / 1 000 000) m,
  • mm: millimetre: (1 / 1 000) m,
  • cm: centimetre: (1 / 100) m,
  • dm: decimetre: (1 / 10) m,
  • m: metre,
  • dam: decametre: 10 m,
  • hm: hectoametre: 100 m,
  • km: kilometre: 1 000 m,
  • nmi: nautical mile: 1 852 m,
  • ft: foot: 0.3048 m,
  • in: inch: 0.0254 m,
  • yd: yard: 0.9144 m,
  • fm: fathom: 1.8288 m,
  • mi: mile: 1 609.344 m,
  • ld: lunar distance: 384 402 000 m,
  • au: astronomical unit: 149 597 870 700 m,
  • ly: light year: 9 460 730 472 580 800 m,
  • pc: parsec: ((648 000 / π) * 149 597 870 700) m.

Returns

• (Object): New Length object.

Example

length(12, 'cm');
// => { value: 12, unit: 'cm' }

Methods

.to(unit)

Arguments

• unit (String): Unit type.

Returns

• (Object): New Length object with value converted to passed unit.

Example

length(100, 'cm').to('m');
// => { value: 1, unit: 'm' }

.add(value, [unit])

Arguments

• value (Number): The number to increment value.
• [unit] (String): Unit type in which the value was given.

Returns

• (Object): New Length object with incremented value.

Example

length(100, 'cm').add(2);
// => { value: 102, unit: 'cm' }
length(100, 'cm').add(2, 'dm');
// => { value: 120, unit: 'cm' }

.toPrecision([digits])

Arguments

• [digits] (Number): The number of digits to appear after the decimal point.

Returns

• (Object): New Length object with fixed value.

Example

length(100, 'cm').toPrecision();
// => { value: 100, unit: 'cm' }
length(100, 'cm').toPrecision(2);
// => { value: 100, unit: 'cm' }
length(0.97982, 'cm').toPrecision(2);
// => { value: 0.98, unit: 'cm' }

.getValue()

Returns

• (Number): Current value.

Example

length(100, 'cm').getValue();
// => 100

.getUnit()

Returns

• (String): Current unit type.

Example

length(100, 'cm').getUnit();
// => cm

.getString(), .toString()

Returns

• (String): String containing value and unit type.

Example

length(100, 'cm').getString();
length(100, 'cm').toString();
// => 100cm
console.log(length(10, 'm') + '');
// => 10m

Contributing

All contributions and suggestions are welcome! For suggested improvements, please create an issue. For direct contributions, please fork the repository, create your feature branch, commit your changes, push commits to the branch and create a new pull request.

License

The code is open source and available under the MIT License.