mt-polygon-simplification/lib/turf-simplify/README.md
2019-07-14 20:37:26 +02:00

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# @turf/simplify
<!-- Generated by documentation.js. Update this documentation by updating the source code. -->
## simplify
Takes a [GeoJSON][1] object and returns a simplified version. Internally uses
[simplify-js][2] to perform simplification using the Ramer-Douglas-Peucker algorithm.
**Parameters**
- `geojson` **[GeoJSON][3]** object to be simplified
- `options` **[Object][4]** Optional parameters (optional, default `{}`)
- `options.tolerance` **[number][5]** simplification tolerance (optional, default `1`)
- `options.highQuality` **[boolean][6]** whether or not to spend more time to create a higher-quality simplification with a different algorithm (optional, default `false`)
- `options.mutate` **[boolean][6]** allows GeoJSON input to be mutated (significant performance increase if true) (optional, default `false`)
**Examples**
```javascript
var geojson = turf.polygon([[
[-70.603637, -33.399918],
[-70.614624, -33.395332],
[-70.639343, -33.392466],
[-70.659942, -33.394759],
[-70.683975, -33.404504],
[-70.697021, -33.419406],
[-70.701141, -33.434306],
[-70.700454, -33.446339],
[-70.694274, -33.458369],
[-70.682601, -33.465816],
[-70.668869, -33.472117],
[-70.646209, -33.473835],
[-70.624923, -33.472117],
[-70.609817, -33.468107],
[-70.595397, -33.458369],
[-70.587158, -33.442901],
[-70.587158, -33.426283],
[-70.590591, -33.414248],
[-70.594711, -33.406224],
[-70.603637, -33.399918]
]]);
var options = {tolerance: 0.01, highQuality: false};
var simplified = turf.simplify(geojson, options);
//addToMap
var addToMap = [geojson, simplified]
```
Returns **[GeoJSON][3]** a simplified GeoJSON
[1]: https://tools.ietf.org/html/rfc7946#section-3
[2]: http://mourner.github.io/simplify-js/
[3]: https://tools.ietf.org/html/rfc7946#section-3
[4]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object
[5]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number
[6]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
<!-- This file is automatically generated. Please don't edit it directly:
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---
This module is part of the [Turfjs project](http://turfjs.org/), an open source
module collection dedicated to geographic algorithms. It is maintained in the
[Turfjs/turf](https://github.com/Turfjs/turf) repository, where you can create
PRs and issues.
### Installation
Install this module individually:
```sh
$ npm install @turf/simplify
```
Or install the Turf module that includes it as a function:
```sh
$ npm install @turf/turf
```