node-red-contrib-tak-registration
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A Node-RED node to register to TAK and to help wrap files as datapackages to send to TAK
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# @turf/moran-index
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## MoranIndex
Type: [object][1]
### Properties
* `moranIndex` **[number][2]** the moran's Index of the observed feature set
* `expectedMoranIndex` **[number][2]** the moran's Index of the random distribution
* `stdNorm` **[number][2]** the standard devitaion of the random distribution
* `zNorm` **[number][2]** the z-score of the observe samples with regard to the random distribution
## moranIndex
Moran's I measures patterns of attribute values associated with features.
The method reveal whether similar values tend to occur near each other,
or whether high or low values are interspersed.
Moran's I > 0 means a clusterd pattern.
Moran's I < 0 means a dispersed pattern.
Moran's I = 0 means a random pattern.
In order to test the significance of the result. The z score is calculated.
A positive enough z-score (ex. >1.96) indicates clustering,
while a negative enough z-score (ex. <-1.96) indicates a dispersed pattern.
the z-score can be calculated based on a normal or random assumption.
**Bibliography**\*
1. [Moran's I][3]
2. [pysal][4]
3. Andy Mitchell, The ESRI Guide to GIS Analysis Volume 2: Spatial Measurements & Statistics.
### Parameters
* `fc` **[FeatureCollection][5]\<any>** 
* `options` **[Object][1]** 
* `options.inputField` **[string][6]** the property name, must contain numeric values
* `options.threshold` **[number][2]** the distance threshold (optional, default `100000`)
* `options.p` **[number][2]** the Minkowski p-norm distance parameter (optional, default `2`)
* `options.binary` **[boolean][7]** whether transfrom the distance to binary (optional, default `false`)
* `options.alpha` **[number][2]** the distance decay parameter (optional, default `-1`)
* `options.standardization` **[boolean][7]** wheter row standardization the distance (optional, default `true`)
### Examples
```javascript
const bbox = [-65, 40, -63, 42];
const dataset = turf.randomPoint(100, { bbox: bbox });
const result = turf.moranIndex(dataset, {
inputField: 'CRIME',
});
```
Returns **[MoranIndex][8]** 
[1]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object
[2]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number
[3]: https://en.wikipedia.org/wiki/Moran%27s_I
[4]: http://pysal.readthedocs.io/en/latest/index.html
[5]: https://tools.ietf.org/html/rfc7946#section-3.3
[6]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String
[7]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
[8]: #moranindex
<!-- This file is automatically generated. Please don't edit it directly. If you find an error, edit the source file of the module in question (likely index.js or index.ts), and re-run "yarn docs" from the root of the turf project. -->
---
This module is part of the [Turfjs project](https://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 single module individually:
```sh
$ npm install @turf/moran-index
```
Or install the all-encompassing @turf/turf module that includes all modules as functions:
```sh
$ npm install @turf/turf
```