mt-geo
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Geodesy representation conversion functions.
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Markdown
mt-geo
======
[](https://travis-ci.org/peterhaldbaek/mt-geo)
Geodesy representation conversion functions.
Installation
------------
```bash
$ npm install mt-geo
```
Usage
-----
The module is initialized like every other Node module.
```js
var geo = require('mt-geo');
```
The module contains functions for converting geodesy representations.
### parseDMS(dms)
Parses string representing degrees/minutes/seconds into numeric degrees.
This is very flexible on formats, allowing signed decimal degrees, or deg-min-sec optionally
suffixed by compass direction (NSEW). A variety of separators are accepted (eg 3º 37' 09"W)
or fixed-width format without separators (eg. 0033709W). Seconds and minutes may be omitted.
(Note minimal validation is done).
- __dms__ (string|number) Degrees or deg/min/sec in variety of formats
```js
var latitude = geo.parseDMS('51° 28′ 40.12″ N');
// => 51.477811
var longitude = geo.parseDMS('000° 00′ 05.31″ W');
// => -0.001475
```
### toDMS(deg, format, dp)
Convert decimal degrees to deg/min/sec format.
Degree, prime, double-prime symbols are added, but sign is discarded, though no compass
direction is added
- __deg__ (number) Degrees
- __format__ (string, optional) Return value as 'd', 'dm', 'dms'
- __dp__ (number, optional) No of decimal places to use - default 0 for dms, 2 for dm, 4 for d
```js
var dms = geo.toDMS('47.54');
// => 047°32′24″
```
### toLat(deg, format, dp)
Convert numeric degrees to deg/min/sec latitude (suffixed with N/S).
- __deg__ (number) Degrees
- __format__ (string, optional) Return value as 'd', 'dm', 'dms'
- __dp__ (number, optional) No of decimal places to use - default 0 for dms, 2 for dm, 4 for d
```js
var latitude = geo.toLat('47.54');
// => 47°32′24″N
```
### toLon(deg, format, dp)
Convert numeric degrees to deg/min/sec longitude (suffixed with E/W).
- __deg__ (number) Degrees
- __format__ (string, optional) Return value as 'd', 'dm', 'dms'
- __dp__ (number, optional) No of decimal places to use - default 0 for dms, 2 for dm, 4 for d
```js
var longitude = geo.toLon('47.54');
// => 047°32′24″E
```
### toBearing(deg, format, dp)
Convert numeric degrees to deg/min/sec as a bearing (0º..360º).
- __deg__ (number) Degrees
- __format__ (string, optional) Return value as 'd', 'dm', 'dms'
- __dp__ (number, optional) No of decimal places to use - default 0 for dms, 2 for dm, 4 for d
```js
var bearing = geo.toBearing('47.54');
// => 047°32′24″
```
Copyright and license
---------------------
The original code was written by Chris Veness and can be found at
http://www.movable-type.co.uk/scripts/latlong.html. It is released under the
simple Creative Commons attribution license
(http://creativecommons.org/licenses/by/3.0/).
This project is released under the MIT license.