65 lines
2.9 KiB
Markdown
65 lines
2.9 KiB
Markdown
# @turf/distance-weight
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<!-- Generated by documentation.js. Update this documentation by updating the source code. -->
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## pNormDistance
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calcualte the Minkowski p-norm distance between two features.
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**Parameters**
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- `feature1` point feature
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- `feature2` point feature
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- `p` p-norm 1=<p<=infinity 1: Manhattan distance 2: Euclidean distance
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## distanceWeight
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**Parameters**
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- `fc` **[FeatureCollection](https://tools.ietf.org/html/rfc7946#section-3.3)<any>** FeatureCollection.
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- `options` **[Object](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object)?** option object.
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- `options.threshold` **[number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** If the distance between neighbor and
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target features is greater than threshold, the weight of that neighbor is 0. (optional, default `10000`)
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- `options.p` **[number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** Minkowski p-norm distance parameter.
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1: Manhattan distance. 2: Euclidean distance. 1=<p<=infinity. (optional, default `2`)
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- `options.binary` **[boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** If true, weight=1 if d <= threshold otherwise weight=0.
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If false, weight=Math.pow(d, alpha). (optional, default `false`)
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- `options.alpha` **[number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)** distance decay parameter.
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A big value means the weight decay quickly as distance increases. (optional, default `-1`)
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- `options.standardization` **[boolean](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean)** row standardization. (optional, default `false`)
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**Examples**
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```javascript
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var bbox = [-65, 40, -63, 42];
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var dataset = turf.randomPoint(100, { bbox: bbox });
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var result = turf.distanceWeight(dataset);
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```
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Returns **[Array](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Array)<[Array](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Array)<[number](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number)>>** distance weight matrix.
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<!-- This file is automatically generated. Please don't edit it directly:
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if you find an error, edit the source file (likely index.js), and re-run
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./scripts/generate-readmes in the turf project. -->
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---
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This module is part of the [Turfjs project](http://turfjs.org/), an open source
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module collection dedicated to geographic algorithms. It is maintained in the
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[Turfjs/turf](https://github.com/Turfjs/turf) repository, where you can create
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PRs and issues.
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### Installation
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Install this module individually:
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```sh
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$ npm install @turf/distance-weight
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```
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Or install the Turf module that includes it as a function:
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```sh
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$ npm install @turf/turf
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```
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